Auto merge of #13200 - Jarcho:constant_no_typeck, r=Alexendoo

Don't use `LateContext` in the constant evaluator

This also changes the interface to require explicitly creating the context. `constant` could be added back in, but the others are probably not worth it.

A couple of bugs have been fixed. The wrong `TypeckResults` was used once when evaluating a constant, and the wrong `ParamEnv` was used by some callers (there wasn't a way to use the correct one).

changelog: none

clippy_lints/src/assertions_on_constants.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_help;
 use clippy_utils::is_inside_always_const_context;
 use clippy_utils::macros::{find_assert_args, root_macro_call_first_node, PanicExpn};
@@ -43,7 +43,7 @@ impl<'tcx> LateLintPass<'tcx> for AssertionsOnConstants {
         let Some((condition, panic_expn)) = find_assert_args(cx, e, macro_call.expn) else {
             return;
         };
-        let Some(Constant::Bool(val)) = constant(cx, cx.typeck_results(), condition) else {
+        let Some(Constant::Bool(val)) = ConstEvalCtxt::new(cx).eval(condition) else {
             return;
         };
 

clippy_lints/src/casts/cast_nan_to_int.rs

@@ -1,6 +1,6 @@
 use super::CAST_NAN_TO_INT;
 
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_note;
 use rustc_hir::Expr;
 use rustc_lint::LateContext;
@@ -20,7 +20,7 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, cast_expr: &Expr<'_>,
 }
 
 fn is_known_nan(cx: &LateContext<'_>, e: &Expr<'_>) -> bool {
-    match constant(cx, cx.typeck_results(), e) {
+    match ConstEvalCtxt::new(cx).eval(e) {
         // FIXME(f16_f128): add these types when nan checks are available on all platforms
         Some(Constant::F64(n)) => n.is_nan(),
         Some(Constant::F32(n)) => n.is_nan(),

clippy_lints/src/casts/cast_possible_truncation.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::{span_lint, span_lint_and_then};
 use clippy_utils::expr_or_init;
 use clippy_utils::source::snippet;
@@ -15,7 +15,7 @@ use rustc_target::abi::IntegerType;
 use super::{utils, CAST_ENUM_TRUNCATION, CAST_POSSIBLE_TRUNCATION};
 
 fn constant_int(cx: &LateContext<'_>, expr: &Expr<'_>) -> Option<u128> {
-    if let Some(Constant::Int(c)) = constant(cx, cx.typeck_results(), expr) {
+    if let Some(Constant::Int(c)) = ConstEvalCtxt::new(cx).eval(expr) {
         Some(c)
     } else {
         None

clippy_lints/src/casts/cast_sign_loss.rs

@@ -1,7 +1,7 @@
 use std::convert::Infallible;
 use std::ops::ControlFlow;
 
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint;
 use clippy_utils::visitors::{for_each_expr_without_closures, Descend};
 use clippy_utils::{method_chain_args, sext};
@@ -88,7 +88,7 @@ fn get_const_signed_int_eval<'cx>(
 ) -> Option<i128> {
     let ty = ty.into().unwrap_or_else(|| cx.typeck_results().expr_ty(expr));
 
-    if let Constant::Int(n) = constant(cx, cx.typeck_results(), expr)?
+    if let Constant::Int(n) = ConstEvalCtxt::new(cx).eval(expr)?
         && let ty::Int(ity) = *ty.kind()
     {
         return Some(sext(cx.tcx, n, ity));
@@ -103,7 +103,7 @@ fn get_const_unsigned_int_eval<'cx>(
 ) -> Option<u128> {
     let ty = ty.into().unwrap_or_else(|| cx.typeck_results().expr_ty(expr));
 
-    if let Constant::Int(n) = constant(cx, cx.typeck_results(), expr)?
+    if let Constant::Int(n) = ConstEvalCtxt::new(cx).eval(expr)?
         && let ty::Uint(_ity) = *ty.kind()
     {
         return Some(n);

clippy_lints/src/enum_clike.rs

@@ -51,7 +51,7 @@ impl<'tcx> LateLintPass<'tcx> for UnportableVariant {
                         .const_eval_poly(def_id.to_def_id())
                         .ok()
                         .map(|val| rustc_middle::mir::Const::from_value(val, ty));
-                    if let Some(Constant::Int(val)) = constant.and_then(|c| mir_to_const(cx, c)) {
+                    if let Some(Constant::Int(val)) = constant.and_then(|c| mir_to_const(cx.tcx, c)) {
                         if let ty::Adt(adt, _) = ty.kind() {
                             if adt.is_enum() {
                                 ty = adt.repr().discr_type().to_ty(cx.tcx);

clippy_lints/src/floating_point_arithmetic.rs

@@ -1,5 +1,5 @@
 use clippy_utils::consts::Constant::{Int, F32, F64};
-use clippy_utils::consts::{constant, constant_simple, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::{
     eq_expr_value, get_parent_expr, higher, is_in_const_context, is_inherent_method_call, is_no_std_crate,
@@ -112,7 +112,7 @@ declare_lint_pass!(FloatingPointArithmetic => [
 // Returns the specialized log method for a given base if base is constant
 // and is one of 2, 10 and e
 fn get_specialized_log_method(cx: &LateContext<'_>, base: &Expr<'_>) -> Option<&'static str> {
-    if let Some(value) = constant(cx, cx.typeck_results(), base) {
+    if let Some(value) = ConstEvalCtxt::new(cx).eval(base) {
         if F32(2.0) == value || F64(2.0) == value {
             return Some("log2");
         } else if F32(10.0) == value || F64(10.0) == value {
@@ -182,10 +182,8 @@ fn check_ln1p(cx: &LateContext<'_>, expr: &Expr<'_>, receiver: &Expr<'_>) {
         rhs,
     ) = receiver.kind
     {
-        let recv = match (
+        let ecx = ConstEvalCtxt::new(cx);
-            constant(cx, cx.typeck_results(), lhs),
+        let recv = match (ecx.eval(lhs), ecx.eval(rhs)) {
-            constant(cx, cx.typeck_results(), rhs),
-        ) {
             (Some(value), _) if F32(1.0) == value || F64(1.0) == value => rhs,
             (_, Some(value)) if F32(1.0) == value || F64(1.0) == value => lhs,
             _ => return,
@@ -230,7 +228,7 @@ fn get_integer_from_float_constant(value: &Constant<'_>) -> Option<i32> {
 
 fn check_powf(cx: &LateContext<'_>, expr: &Expr<'_>, receiver: &Expr<'_>, args: &[Expr<'_>]) {
     // Check receiver
-    if let Some(value) = constant(cx, cx.typeck_results(), receiver) {
+    if let Some(value) = ConstEvalCtxt::new(cx).eval(receiver) {
         if let Some(method) = if F32(f32_consts::E) == value || F64(f64_consts::E) == value {
             Some("exp")
         } else if F32(2.0) == value || F64(2.0) == value {
@@ -251,7 +249,7 @@ fn check_powf(cx: &LateContext<'_>, expr: &Expr<'_>, receiver: &Expr<'_>, args:
     }
 
     // Check argument
-    if let Some(value) = constant(cx, cx.typeck_results(), &args[0]) {
+    if let Some(value) = ConstEvalCtxt::new(cx).eval(&args[0]) {
         let (lint, help, suggestion) = if F32(1.0 / 2.0) == value || F64(1.0 / 2.0) == value {
             (
                 SUBOPTIMAL_FLOPS,
@@ -291,7 +289,7 @@ fn check_powf(cx: &LateContext<'_>, expr: &Expr<'_>, receiver: &Expr<'_>, args:
 }
 
 fn check_powi(cx: &LateContext<'_>, expr: &Expr<'_>, receiver: &Expr<'_>, args: &[Expr<'_>]) {
-    if let Some(value) = constant(cx, cx.typeck_results(), &args[0]) {
+    if let Some(value) = ConstEvalCtxt::new(cx).eval(&args[0]) {
         if value == Int(2) {
             if let Some(parent) = get_parent_expr(cx, expr) {
                 if let Some(grandparent) = get_parent_expr(cx, parent) {
@@ -397,8 +395,9 @@ fn detect_hypot(cx: &LateContext<'_>, receiver: &Expr<'_>) -> Option<String> {
             ) = &add_rhs.kind
             && lmethod_name.as_str() == "powi"
             && rmethod_name.as_str() == "powi"
-            && let Some(lvalue) = constant(cx, cx.typeck_results(), largs_1)
+            && let ecx = ConstEvalCtxt::new(cx)
-            && let Some(rvalue) = constant(cx, cx.typeck_results(), rargs_1)
+            && let Some(lvalue) = ecx.eval(largs_1)
+            && let Some(rvalue) = ecx.eval(rargs_1)
             && Int(2) == lvalue
             && Int(2) == rvalue
         {
@@ -438,7 +437,7 @@ fn check_expm1(cx: &LateContext<'_>, expr: &Expr<'_>) {
         rhs,
     ) = expr.kind
         && cx.typeck_results().expr_ty(lhs).is_floating_point()
-        && let Some(value) = constant(cx, cx.typeck_results(), rhs)
+        && let Some(value) = ConstEvalCtxt::new(cx).eval(rhs)
         && (F32(1.0) == value || F64(1.0) == value)
         && let ExprKind::MethodCall(path, self_arg, ..) = &lhs.kind
         && cx.typeck_results().expr_ty(self_arg).is_floating_point()
@@ -552,7 +551,7 @@ fn is_testing_negative(cx: &LateContext<'_>, expr: &Expr<'_>, test: &Expr<'_>) -
 
 /// Returns true iff expr is some zero literal
 fn is_zero(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
-    match constant_simple(cx, cx.typeck_results(), expr) {
+    match ConstEvalCtxt::new(cx).eval_simple(expr) {
         Some(Int(i)) => i == 0,
         Some(F32(f)) => f == 0.0,
         Some(F64(f)) => f == 0.0,
@@ -696,8 +695,9 @@ fn check_radians(cx: &LateContext<'_>, expr: &Expr<'_>) {
             mul_lhs,
             mul_rhs,
         ) = &div_lhs.kind
-        && let Some(rvalue) = constant(cx, cx.typeck_results(), div_rhs)
+        && let ecx = ConstEvalCtxt::new(cx)
-        && let Some(lvalue) = constant(cx, cx.typeck_results(), mul_rhs)
+        && let Some(rvalue) = ecx.eval(div_rhs)
+        && let Some(lvalue) = ecx.eval(mul_rhs)
     {
         // TODO: also check for constant values near PI/180 or 180/PI
         if (F32(f32_consts::PI) == rvalue || F64(f64_consts::PI) == rvalue)

clippy_lints/src/if_not_else.rs

@@ -1,7 +1,7 @@
 //! lint on if branches that could be swapped so no `!` operation is necessary
 //! on the condition
 
-use clippy_utils::consts::{constant_simple, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_help;
 use clippy_utils::is_else_clause;
 use rustc_hir::{BinOpKind, Expr, ExprKind, UnOp};
@@ -49,7 +49,7 @@ declare_clippy_lint! {
 declare_lint_pass!(IfNotElse => [IF_NOT_ELSE]);
 
 fn is_zero_const(expr: &Expr<'_>, cx: &LateContext<'_>) -> bool {
-    if let Some(value) = constant_simple(cx, cx.typeck_results(), expr) {
+    if let Some(value) = ConstEvalCtxt::new(cx).eval_simple(expr) {
         return Constant::Int(0) == value;
     }
     false

clippy_lints/src/implicit_saturating_add.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::get_parent_expr;
 use clippy_utils::source::snippet_with_context;
@@ -117,11 +117,11 @@ fn get_int_max(ty: Ty<'_>) -> Option<u128> {
 
 fn get_const<'tcx>(cx: &LateContext<'tcx>, expr: &Expr<'tcx>) -> Option<(u128, BinOpKind, &'tcx Expr<'tcx>)> {
     if let ExprKind::Binary(op, l, r) = expr.kind {
-        let tr = cx.typeck_results();
+        let ecx = ConstEvalCtxt::new(cx);
-        if let Some(Constant::Int(c)) = constant(cx, tr, r) {
+        if let Some(Constant::Int(c)) = ecx.eval(r) {
             return Some((c, op.node, l));
         };
-        if let Some(Constant::Int(c)) = constant(cx, tr, l) {
+        if let Some(Constant::Int(c)) = ecx.eval(l) {
             return Some((c, invert_op(op.node)?, r));
         }
     }

clippy_lints/src/index_refutable_slice.rs

@@ -1,6 +1,6 @@
 use clippy_config::msrvs::{self, Msrv};
 use clippy_config::Conf;
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::higher::IfLet;
 use clippy_utils::ty::is_copy;
@@ -246,7 +246,7 @@ impl<'a, 'tcx> Visitor<'tcx> for SliceIndexLintingVisitor<'a, 'tcx> {
                 && let parent_id = cx.tcx.parent_hir_id(expr.hir_id)
                 && let hir::Node::Expr(parent_expr) = cx.tcx.hir_node(parent_id)
                 && let hir::ExprKind::Index(_, index_expr, _) = parent_expr.kind
-                && let Some(Constant::Int(index_value)) = constant(cx, cx.typeck_results(), index_expr)
+                && let Some(Constant::Int(index_value)) = ConstEvalCtxt::new(cx).eval(index_expr)
                 && let Ok(index_value) = index_value.try_into()
                 && index_value < max_suggested_slice
 

clippy_lints/src/indexing_slicing.rs

@@ -1,7 +1,7 @@
 //! lint on indexing and slicing operations
 
 use clippy_config::Conf;
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::{span_lint, span_lint_and_then};
 use clippy_utils::ty::{deref_chain, get_adt_inherent_method};
 use clippy_utils::{higher, is_from_proc_macro};
@@ -177,7 +177,7 @@ impl<'tcx> LateLintPass<'tcx> for IndexingSlicing {
                         return;
                     }
                     // Index is a constant uint.
-                    if let Some(constant) = constant(cx, cx.typeck_results(), index) {
+                    if let Some(constant) = ConstEvalCtxt::new(cx).eval(index) {
                         // only `usize` index is legal in rust array index
                         // leave other type to rustc
                         if let Constant::Int(off) = constant
@@ -215,14 +215,15 @@ impl<'tcx> LateLintPass<'tcx> for IndexingSlicing {
 /// Returns a tuple of options with the start and end (exclusive) values of
 /// the range. If the start or end is not constant, None is returned.
 fn to_const_range(cx: &LateContext<'_>, range: higher::Range<'_>, array_size: u128) -> (Option<u128>, Option<u128>) {
-    let s = range.start.map(|expr| constant(cx, cx.typeck_results(), expr));
+    let ecx = ConstEvalCtxt::new(cx);
+    let s = range.start.map(|expr| ecx.eval(expr));
     let start = match s {
         Some(Some(Constant::Int(x))) => Some(x),
         Some(_) => None,
         None => Some(0),
     };
 
-    let e = range.end.map(|expr| constant(cx, cx.typeck_results(), expr));
+    let e = range.end.map(|expr| ecx.eval(expr));
     let end = match e {
         Some(Some(Constant::Int(x))) => {
             if range.limits == RangeLimits::Closed {

clippy_lints/src/invalid_upcast_comparisons.rs

@@ -7,7 +7,7 @@ use rustc_span::Span;
 
 use clippy_utils::comparisons;
 use clippy_utils::comparisons::Rel;
-use clippy_utils::consts::{constant_full_int, FullInt};
+use clippy_utils::consts::{ConstEvalCtxt, FullInt};
 use clippy_utils::diagnostics::span_lint;
 use clippy_utils::source::snippet;
 
@@ -95,7 +95,7 @@ fn upcast_comparison_bounds_err<'tcx>(
     invert: bool,
 ) {
     if let Some((lb, ub)) = lhs_bounds {
-        if let Some(norm_rhs_val) = constant_full_int(cx, cx.typeck_results(), rhs) {
+        if let Some(norm_rhs_val) = ConstEvalCtxt::new(cx).eval_full_int(rhs) {
             if rel == Rel::Eq || rel == Rel::Ne {
                 if norm_rhs_val < lb || norm_rhs_val > ub {
                     err_upcast_comparison(cx, span, lhs, rel == Rel::Ne);

clippy_lints/src/loops/while_immutable_condition.rs

@@ -1,5 +1,5 @@
 use super::WHILE_IMMUTABLE_CONDITION;
-use clippy_utils::consts::constant;
+use clippy_utils::consts::ConstEvalCtxt;
 use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::usage::mutated_variables;
 use rustc_hir::def::{DefKind, Res};
@@ -10,7 +10,7 @@ use rustc_lint::LateContext;
 use std::ops::ControlFlow;
 
 pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, cond: &'tcx Expr<'_>, expr: &'tcx Expr<'_>) {
-    if constant(cx, cx.typeck_results(), cond).is_some() {
+    if ConstEvalCtxt::new(cx).eval(cond).is_some() {
         // A pure constant condition (e.g., `while false`) is not linted.
         return;
     }

clippy_lints/src/manual_clamp.rs

@@ -1,6 +1,6 @@
 use clippy_config::msrvs::{self, Msrv};
 use clippy_config::Conf;
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::{span_lint_and_then, span_lint_hir_and_then};
 use clippy_utils::higher::If;
 use clippy_utils::sugg::Sugg;
@@ -122,8 +122,9 @@ impl<'tcx> ClampSuggestion<'tcx> {
         if max_type != min_type {
             return false;
         }
-        if let Some(max) = constant(cx, cx.typeck_results(), self.params.max)
+        let ecx = ConstEvalCtxt::new(cx);
-            && let Some(min) = constant(cx, cx.typeck_results(), self.params.min)
+        if let Some(max) = ecx.eval(self.params.max)
+            && let Some(min) = ecx.eval(self.params.min)
             && let Some(ord) = Constant::partial_cmp(cx.tcx, max_type, &min, &max)
         {
             ord != Ordering::Greater

clippy_lints/src/manual_float_methods.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::source::snippet_opt;
 use clippy_utils::{is_from_proc_macro, path_to_local};
@@ -95,8 +95,9 @@ impl<'tcx> LateLintPass<'tcx> for ManualFloatMethods {
                     || cx.tcx.features().declared(sym!(const_float_classify))
             )
             && let [first, second, const_1, const_2] = exprs
-            && let Some(const_1) = constant(cx, cx.typeck_results(), const_1)
+            && let ecx = ConstEvalCtxt::new(cx)
-            && let Some(const_2) = constant(cx, cx.typeck_results(), const_2)
+            && let Some(const_1) = ecx.eval(const_1)
+            && let Some(const_2) = ecx.eval(const_2)
             && path_to_local(first).is_some_and(|f| path_to_local(second).is_some_and(|s| f == s))
             // The actual infinity check, we also allow `NEG_INFINITY` before` INFINITY` just in
             // case somebody does that for some reason

clippy_lints/src/manual_rem_euclid.rs

@@ -1,6 +1,6 @@
 use clippy_config::msrvs::{self, Msrv};
 use clippy_config::Conf;
-use clippy_utils::consts::{constant_full_int, FullInt};
+use clippy_utils::consts::{ConstEvalCtxt, FullInt};
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::source::snippet_with_context;
 use clippy_utils::{is_in_const_context, path_to_local};
@@ -117,7 +117,7 @@ fn check_for_either_unsigned_int_constant<'a>(
 }
 
 fn check_for_unsigned_int_constant<'a>(cx: &'a LateContext<'_>, expr: &'a Expr<'_>) -> Option<u128> {
-    let int_const = constant_full_int(cx, cx.typeck_results(), expr)?;
+    let int_const = ConstEvalCtxt::new(cx).eval_full_int(expr)?;
     match int_const {
         FullInt::S(s) => s.try_into().ok(),
         FullInt::U(u) => Some(u),

clippy_lints/src/manual_rotate.rs

@@ -1,6 +1,6 @@
 use std::fmt::Display;
 
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::sugg;
 use rustc_errors::Applicability;
@@ -66,7 +66,7 @@ fn parse_shift<'tcx>(
             BinOpKind::Shr => ShiftDirection::Right,
             _ => return None,
         };
-        let const_expr = constant(cx, cx.typeck_results(), r)?;
+        let const_expr = ConstEvalCtxt::new(cx).eval(r)?;
         if let Constant::Int(shift) = const_expr {
             return Some((dir, shift, l));
         }

clippy_lints/src/manual_strip.rs

@@ -1,6 +1,6 @@
 use clippy_config::msrvs::{self, Msrv};
 use clippy_config::Conf;
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::source::snippet;
 use clippy_utils::usage::mutated_variables;
@@ -147,7 +147,7 @@ fn len_arg<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) -> Option<&'tcx E
 
 // Returns the length of the `expr` if it's a constant string or char.
 fn constant_length(cx: &LateContext<'_>, expr: &Expr<'_>) -> Option<u128> {
-    let value = constant(cx, cx.typeck_results(), expr)?;
+    let value = ConstEvalCtxt::new(cx).eval(expr)?;
     match value {
         Constant::Str(value) => Some(value.len() as u128),
         Constant::Char(value) => Some(value.len_utf8() as u128),

clippy_lints/src/matches/manual_unwrap_or.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::constant_simple;
+use clippy_utils::consts::ConstEvalCtxt;
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::source::{indent_of, reindent_multiline, snippet_opt};
 use clippy_utils::ty::is_type_diagnostic_item;
@@ -69,7 +69,7 @@ fn check_and_lint<'tcx>(
         && let Some(ty_name) = find_type_name(cx, ty)
         && let Some(or_body_snippet) = snippet_opt(cx, else_expr.span)
         && let Some(indent) = indent_of(cx, expr.span)
-        && constant_simple(cx, cx.typeck_results(), else_expr).is_some()
+        && ConstEvalCtxt::new(cx).eval_simple(else_expr).is_some()
     {
         lint(cx, expr, let_expr, ty_name, or_body_snippet, indent);
     }

clippy_lints/src/matches/overlapping_arms.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant, constant_full_int, mir_to_const, FullInt};
+use clippy_utils::consts::{mir_to_const, ConstEvalCtxt, FullInt};
 use clippy_utils::diagnostics::span_lint_and_note;
 use core::cmp::Ordering;
 use rustc_hir::{Arm, Expr, PatKind, RangeEnd};
@@ -34,19 +34,19 @@ fn all_ranges<'tcx>(cx: &LateContext<'tcx>, arms: &'tcx [Arm<'_>], ty: Ty<'tcx>)
             if let Arm { pat, guard: None, .. } = *arm {
                 if let PatKind::Range(ref lhs, ref rhs, range_end) = pat.kind {
                     let lhs_const = if let Some(lhs) = lhs {
-                        constant(cx, cx.typeck_results(), lhs)?
+                        ConstEvalCtxt::new(cx).eval(lhs)?
                     } else {
                         let min_val_const = ty.numeric_min_val(cx.tcx)?;
-                        mir_to_const(cx, mir::Const::from_ty_const(min_val_const, ty, cx.tcx))?
+                        mir_to_const(cx.tcx, mir::Const::from_ty_const(min_val_const, ty, cx.tcx))?
                     };
                     let rhs_const = if let Some(rhs) = rhs {
-                        constant(cx, cx.typeck_results(), rhs)?
+                        ConstEvalCtxt::new(cx).eval(rhs)?
                     } else {
                         let max_val_const = ty.numeric_max_val(cx.tcx)?;
-                        mir_to_const(cx, mir::Const::from_ty_const(max_val_const, ty, cx.tcx))?
+                        mir_to_const(cx.tcx, mir::Const::from_ty_const(max_val_const, ty, cx.tcx))?
                     };
-                    let lhs_val = lhs_const.int_value(cx, ty)?;
+                    let lhs_val = lhs_const.int_value(cx.tcx, ty)?;
-                    let rhs_val = rhs_const.int_value(cx, ty)?;
+                    let rhs_val = rhs_const.int_value(cx.tcx, ty)?;
                     let rhs_bound = match range_end {
                         RangeEnd::Included => EndBound::Included(rhs_val),
                         RangeEnd::Excluded => EndBound::Excluded(rhs_val),
@@ -58,7 +58,7 @@ fn all_ranges<'tcx>(cx: &LateContext<'tcx>, arms: &'tcx [Arm<'_>], ty: Ty<'tcx>)
                 }
 
                 if let PatKind::Lit(value) = pat.kind {
-                    let value = constant_full_int(cx, cx.typeck_results(), value)?;
+                    let value = ConstEvalCtxt::new(cx).eval_full_int(value)?;
                     return Some(SpannedRange {
                         span: pat.span,
                         node: (value, EndBound::Included(value)),

clippy_lints/src/methods/is_digit_ascii_radix.rs

@@ -2,7 +2,7 @@
 
 use super::IS_DIGIT_ASCII_RADIX;
 use clippy_config::msrvs::{self, Msrv};
-use clippy_utils::consts::{constant_full_int, FullInt};
+use clippy_utils::consts::{ConstEvalCtxt, FullInt};
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::source::snippet_with_applicability;
 use rustc_errors::Applicability;
@@ -24,7 +24,7 @@ pub(super) fn check<'tcx>(
         return;
     }
 
-    if let Some(radix_val) = constant_full_int(cx, cx.typeck_results(), radix) {
+    if let Some(radix_val) = ConstEvalCtxt::new(cx).eval_full_int(radix) {
         let (num, replacement) = match radix_val {
             FullInt::S(10) | FullInt::U(10) => (10, "is_ascii_digit"),
             FullInt::S(16) | FullInt::U(16) => (16, "is_ascii_hexdigit"),

clippy_lints/src/methods/is_empty.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::constant_is_empty;
+use clippy_utils::consts::ConstEvalCtxt;
 use clippy_utils::diagnostics::span_lint;
 use clippy_utils::{find_binding_init, path_to_local};
 use rustc_hir::{Expr, HirId};
@@ -18,7 +18,7 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &'_ Expr<'_>, receiver: &Expr<'_
     if !receiver.span.eq_ctxt(init_expr.span) {
         return;
     }
-    if let Some(init_is_empty) = constant_is_empty(cx, init_expr) {
+    if let Some(init_is_empty) = ConstEvalCtxt::new(cx).eval_is_empty(init_expr) {
         span_lint(
             cx,
             CONST_IS_EMPTY,

clippy_lints/src/methods/iter_nth_zero.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::source::snippet_with_applicability;
 use clippy_utils::{is_lang_item_or_ctor, is_trait_method};
@@ -14,7 +14,7 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &hir::Expr<'_>, recv: &hir::Expr
     if let OwnerNode::Item(item) = cx.tcx.hir_owner_node(cx.tcx.hir().get_parent_item(expr.hir_id))
         && let def_id = item.owner_id.to_def_id()
         && is_trait_method(cx, expr, sym::Iterator)
-        && let Some(Constant::Int(0)) = constant(cx, cx.typeck_results(), arg)
+        && let Some(Constant::Int(0)) = ConstEvalCtxt::new(cx).eval(arg)
         && !is_lang_item_or_ctor(cx, def_id, LangItem::IteratorNext)
     {
         let mut app = Applicability::MachineApplicable;

clippy_lints/src/methods/iter_skip_zero.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::{is_from_proc_macro, is_trait_method};
 use rustc_errors::Applicability;
@@ -11,7 +11,7 @@ use super::ITER_SKIP_ZERO;
 pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>, arg_expr: &Expr<'_>) {
     if !expr.span.from_expansion()
         && is_trait_method(cx, expr, sym::Iterator)
-        && let Some(arg) = constant(cx, cx.typeck_results(), arg_expr).and_then(|constant| {
+        && let Some(arg) = ConstEvalCtxt::new(cx).eval(arg_expr).and_then(|constant| {
             if let Constant::Int(arg) = constant {
                 Some(arg)
             } else {

clippy_lints/src/methods/iterator_step_by_zero.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint;
 use clippy_utils::is_trait_method;
 use rustc_hir as hir;
@@ -9,7 +9,7 @@ use super::ITERATOR_STEP_BY_ZERO;
 
 pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, expr: &hir::Expr<'_>, arg: &'tcx hir::Expr<'_>) {
     if is_trait_method(cx, expr, sym::Iterator) {
-        if let Some(Constant::Int(0)) = constant(cx, cx.typeck_results(), arg) {
+        if let Some(Constant::Int(0)) = ConstEvalCtxt::new(cx).eval(arg) {
             span_lint(
                 cx,
                 ITERATOR_STEP_BY_ZERO,

clippy_lints/src/methods/mod.rs

@@ -133,7 +133,7 @@ mod zst_offset;
 
 use clippy_config::msrvs::{self, Msrv};
 use clippy_config::Conf;
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::{span_lint, span_lint_and_help};
 use clippy_utils::macros::FormatArgsStorage;
 use clippy_utils::ty::{contains_ty_adt_constructor_opaque, implements_trait, is_copy, is_type_diagnostic_item};
@@ -4915,13 +4915,13 @@ impl Methods {
                     str_split::check(cx, expr, recv, arg);
                 },
                 ("splitn" | "rsplitn", [count_arg, pat_arg]) => {
-                    if let Some(Constant::Int(count)) = constant(cx, cx.typeck_results(), count_arg) {
+                    if let Some(Constant::Int(count)) = ConstEvalCtxt::new(cx).eval(count_arg) {
                         suspicious_splitn::check(cx, name, expr, recv, count);
                         str_splitn::check(cx, name, expr, recv, pat_arg, count, &self.msrv);
                     }
                 },
                 ("splitn_mut" | "rsplitn_mut", [count_arg, _]) => {
-                    if let Some(Constant::Int(count)) = constant(cx, cx.typeck_results(), count_arg) {
+                    if let Some(Constant::Int(count)) = ConstEvalCtxt::new(cx).eval(count_arg) {
                         suspicious_splitn::check(cx, name, expr, recv, count);
                     }
                 },

clippy_lints/src/methods/repeat_once.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::source::snippet;
 use clippy_utils::ty::is_type_lang_item;
@@ -14,7 +14,7 @@ pub(super) fn check<'tcx>(
     recv: &'tcx Expr<'_>,
     repeat_arg: &'tcx Expr<'_>,
 ) {
-    if constant(cx, cx.typeck_results(), repeat_arg) == Some(Constant::Int(1)) {
+    if ConstEvalCtxt::new(cx).eval(repeat_arg) == Some(Constant::Int(1)) {
         let ty = cx.typeck_results().expr_ty(recv).peel_refs();
         if ty.is_str() {
             span_lint_and_sugg(

clippy_lints/src/methods/str_splitn.rs

@@ -1,5 +1,5 @@
 use clippy_config::msrvs::{self, Msrv};
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::{span_lint_and_sugg, span_lint_and_then};
 use clippy_utils::source::snippet_with_context;
 use clippy_utils::usage::local_used_after_expr;
@@ -301,7 +301,7 @@ fn parse_iter_usage<'tcx>(
                     };
                 },
                 ("nth" | "skip", [idx_expr]) if cx.tcx.trait_of_item(did) == Some(iter_id) => {
-                    if let Some(Constant::Int(idx)) = constant(cx, cx.typeck_results(), idx_expr) {
+                    if let Some(Constant::Int(idx)) = ConstEvalCtxt::new(cx).eval(idx_expr) {
                         let span = if name.ident.as_str() == "nth" {
                             e.span
                         } else if let Some((_, Node::Expr(next_expr))) = iter.next()

clippy_lints/src/methods/unnecessary_min_or_max.rs

@@ -3,7 +3,7 @@ use std::cmp::Ordering;
 use super::UNNECESSARY_MIN_OR_MAX;
 use clippy_utils::diagnostics::span_lint_and_sugg;
 
-use clippy_utils::consts::{constant, constant_with_source, Constant, ConstantSource, FullInt};
+use clippy_utils::consts::{ConstEvalCtxt, Constant, ConstantSource, FullInt};
 use clippy_utils::source::snippet;
 
 use rustc_errors::Applicability;
@@ -20,10 +20,9 @@ pub(super) fn check<'tcx>(
     arg: &'tcx Expr<'_>,
 ) {
     let typeck_results = cx.typeck_results();
-    if let Some((left, ConstantSource::Local | ConstantSource::CoreConstant)) =
+    let ecx = ConstEvalCtxt::with_env(cx.tcx, cx.param_env, typeck_results);
-        constant_with_source(cx, typeck_results, recv)
+    if let Some((left, ConstantSource::Local | ConstantSource::CoreConstant)) = ecx.eval_with_source(recv)
-        && let Some((right, ConstantSource::Local | ConstantSource::CoreConstant)) =
+        && let Some((right, ConstantSource::Local | ConstantSource::CoreConstant)) = ecx.eval_with_source(arg)
-            constant_with_source(cx, typeck_results, arg)
     {
         let Some(ord) = Constant::partial_cmp(cx.tcx, typeck_results.expr_ty(recv), &left, &right) else {
             return;
@@ -78,9 +77,9 @@ enum Extrema {
 fn detect_extrema<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) -> Option<Extrema> {
     let ty = cx.typeck_results().expr_ty(expr);
 
-    let cv = constant(cx, cx.typeck_results(), expr)?;
+    let cv = ConstEvalCtxt::new(cx).eval(expr)?;
 
-    match (cv.int_value(cx, ty)?, ty.kind()) {
+    match (cv.int_value(cx.tcx, ty)?, ty.kind()) {
         (FullInt::S(i), &ty::Int(ity)) if i == i128::MIN >> (128 - ity.bit_width()?) => Some(Extrema::Minimum),
         (FullInt::S(i), &ty::Int(ity)) if i == i128::MAX >> (128 - ity.bit_width()?) => Some(Extrema::Maximum),
         (FullInt::U(i), &ty::Uint(uty)) if i == u128::MAX >> (128 - uty.bit_width()?) => Some(Extrema::Maximum),

clippy_lints/src/minmax.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant_simple, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint;
 use clippy_utils::is_trait_method;
 use rustc_hir::{Expr, ExprKind};
@@ -106,15 +106,11 @@ fn fetch_const<'a, 'tcx>(
     if args.next().is_some() {
         return None;
     }
-    constant_simple(cx, cx.typeck_results(), first_arg).map_or_else(
+    let ecx = ConstEvalCtxt::new(cx);
-        || constant_simple(cx, cx.typeck_results(), second_arg).map(|c| (m, c, first_arg)),
+    match (ecx.eval_simple(first_arg), ecx.eval_simple(second_arg)) {
-        |c| {
+        (Some(c), None) => Some((m, c, second_arg)),
-            if constant_simple(cx, cx.typeck_results(), second_arg).is_none() {
+        (None, Some(c)) => Some((m, c, first_arg)),
-                // otherwise ignore
+        // otherwise ignore
-                Some((m, c, second_arg))
+        _ => None,
-            } else {
+    }
-                None
-            }
-        },
-    )
 }

clippy_lints/src/operators/absurd_extreme_comparisons.rs

@@ -3,7 +3,7 @@ use rustc_lint::LateContext;
 use rustc_middle::ty;
 
 use clippy_utils::comparisons::{normalize_comparison, Rel};
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_help;
 use clippy_utils::source::snippet;
 use clippy_utils::ty::is_isize_or_usize;
@@ -121,7 +121,7 @@ fn detect_absurd_comparison<'tcx>(
 fn detect_extreme_expr<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) -> Option<ExtremeExpr<'tcx>> {
     let ty = cx.typeck_results().expr_ty(expr);
 
-    let cv = constant(cx, cx.typeck_results(), expr)?;
+    let cv = ConstEvalCtxt::new(cx).eval(expr)?;
 
     let which = match (ty.kind(), cv) {
         (&ty::Bool, Constant::Bool(false)) | (&ty::Uint(_), Constant::Int(0)) => ExtremeType::Minimum,

clippy_lints/src/operators/arithmetic_side_effects.rs

@@ -1,6 +1,6 @@
 use super::ARITHMETIC_SIDE_EFFECTS;
 use clippy_config::Conf;
-use clippy_utils::consts::{constant, constant_simple, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint;
 use clippy_utils::ty::is_type_diagnostic_item;
 use clippy_utils::{expr_or_init, is_from_proc_macro, is_lint_allowed, peel_hir_expr_refs, peel_hir_expr_unary};
@@ -162,7 +162,7 @@ impl ArithmeticSideEffects {
         {
             return Some(n.get());
         }
-        if let Some(Constant::Int(n)) = constant(cx, cx.typeck_results(), expr) {
+        if let Some(Constant::Int(n)) = ConstEvalCtxt::new(cx).eval(expr) {
             return Some(n);
         }
         None
@@ -200,7 +200,7 @@ impl ArithmeticSideEffects {
         lhs: &'tcx hir::Expr<'_>,
         rhs: &'tcx hir::Expr<'_>,
     ) {
-        if constant_simple(cx, cx.typeck_results(), expr).is_some() {
+        if ConstEvalCtxt::new(cx).eval_simple(expr).is_some() {
             return;
         }
         if !matches!(
@@ -280,7 +280,7 @@ impl ArithmeticSideEffects {
         let Some(arg) = args.first() else {
             return;
         };
-        if constant_simple(cx, cx.typeck_results(), receiver).is_some() {
+        if ConstEvalCtxt::new(cx).eval_simple(receiver).is_some() {
             return;
         }
         let instance_ty = cx.typeck_results().expr_ty(receiver);
@@ -308,7 +308,7 @@ impl ArithmeticSideEffects {
         let hir::UnOp::Neg = un_op else {
             return;
         };
-        if constant(cx, cx.typeck_results(), un_expr).is_some() {
+        if ConstEvalCtxt::new(cx).eval(un_expr).is_some() {
             return;
         }
         let ty = cx.typeck_results().expr_ty(expr).peel_refs();

clippy_lints/src/operators/bit_mask.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint;
 use rustc_hir::{BinOpKind, Expr, ExprKind};
 use rustc_lint::LateContext;
@@ -166,7 +166,7 @@ fn check_ineffective_gt(cx: &LateContext<'_>, span: Span, m: u128, c: u128, op:
 }
 
 fn fetch_int_literal(cx: &LateContext<'_>, lit: &Expr<'_>) -> Option<u128> {
-    match constant(cx, cx.typeck_results(), lit)? {
+    match ConstEvalCtxt::new(cx).eval(lit)? {
         Constant::Int(n) => Some(n),
         _ => None,
     }

clippy_lints/src/operators/const_comparisons.rs

@@ -2,7 +2,7 @@
 
 use std::cmp::Ordering;
 
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use rustc_hir::{BinOpKind, Expr, ExprKind};
 use rustc_lint::LateContext;
 use rustc_middle::ty::layout::HasTyCtxt;
@@ -20,13 +20,14 @@ use super::{IMPOSSIBLE_COMPARISONS, REDUNDANT_COMPARISONS};
 // Flip yoda conditionals, turnings expressions like `42 < x` into `x > 42`
 fn comparison_to_const<'tcx>(
     cx: &LateContext<'tcx>,
-    typeck: &TypeckResults<'tcx>,
+    typeck: &'tcx TypeckResults<'tcx>,
     expr: &'tcx Expr<'tcx>,
 ) -> Option<(CmpOp, &'tcx Expr<'tcx>, &'tcx Expr<'tcx>, Constant<'tcx>, Ty<'tcx>)> {
     if let ExprKind::Binary(operator, left, right) = expr.kind
         && let Ok(cmp_op) = CmpOp::try_from(operator.node)
     {
-        match (constant(cx, typeck, left), constant(cx, typeck, right)) {
+        let ecx = ConstEvalCtxt::with_env(cx.tcx, cx.param_env, typeck);
+        match (ecx.eval(left), ecx.eval(right)) {
             (Some(_), Some(_)) => None,
             (_, Some(con)) => Some((cmp_op, left, right, con, typeck.expr_ty(right))),
             (Some(con), _) => Some((cmp_op.reverse(), right, left, con, typeck.expr_ty(left))),

clippy_lints/src/operators/duration_subsec.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::source::snippet_with_applicability;
 use clippy_utils::ty::is_type_diagnostic_item;
@@ -19,7 +19,7 @@ pub(crate) fn check<'tcx>(
     if op == BinOpKind::Div
         && let ExprKind::MethodCall(method_path, self_arg, [], _) = left.kind
         && is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(self_arg).peel_refs(), sym::Duration)
-        && let Some(Constant::Int(divisor)) = constant(cx, cx.typeck_results(), right)
+        && let Some(Constant::Int(divisor)) = ConstEvalCtxt::new(cx).eval(right)
     {
         let suggested_fn = match (method_path.ident.as_str(), divisor) {
             ("subsec_micros", 1_000) | ("subsec_nanos", 1_000_000) => "subsec_millis",

clippy_lints/src/operators/erasing_op.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant_simple, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint;
 use clippy_utils::ty::same_type_and_consts;
 
@@ -34,12 +34,12 @@ fn different_types(tck: &TypeckResults<'_>, input: &Expr<'_>, output: &Expr<'_>)
 
 fn check_op<'tcx>(
     cx: &LateContext<'tcx>,
-    tck: &TypeckResults<'tcx>,
+    tck: &'tcx TypeckResults<'tcx>,
     op: &Expr<'tcx>,
     other: &Expr<'tcx>,
     parent: &Expr<'tcx>,
 ) {
-    if constant_simple(cx, tck, op) == Some(Constant::Int(0)) {
+    if ConstEvalCtxt::with_env(cx.tcx, cx.param_env, tck).eval_simple(op) == Some(Constant::Int(0)) {
         if different_types(tck, other, parent) {
             return;
         }

clippy_lints/src/operators/float_cmp.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant_with_source, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::get_item_name;
 use clippy_utils::sugg::Sugg;
@@ -17,12 +17,14 @@ pub(crate) fn check<'tcx>(
     right: &'tcx Expr<'_>,
 ) {
     if (op == BinOpKind::Eq || op == BinOpKind::Ne) && is_float(cx, left) {
-        let left_is_local = match constant_with_source(cx, cx.typeck_results(), left) {
+        let typeck = cx.typeck_results();
+        let ecx = ConstEvalCtxt::with_env(cx.tcx, cx.param_env, typeck);
+        let left_is_local = match ecx.eval_with_source(left) {
             Some((c, s)) if !is_allowed(&c) => s.is_local(),
             Some(_) => return,
             None => true,
         };
-        let right_is_local = match constant_with_source(cx, cx.typeck_results(), right) {
+        let right_is_local = match ecx.eval_with_source(right) {
             Some((c, s)) if !is_allowed(&c) => s.is_local(),
             Some(_) => return,
             None => true,

clippy_lints/src/operators/identity_op.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant_full_int, constant_simple, Constant, FullInt};
+use clippy_utils::consts::{ConstEvalCtxt, Constant, FullInt};
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::source::snippet_with_applicability;
 use clippy_utils::{clip, peel_hir_expr_refs, unsext};
@@ -184,14 +184,13 @@ fn is_allowed(cx: &LateContext<'_>, cmp: BinOpKind, left: &Expr<'_>, right: &Exp
         && cx.typeck_results().expr_ty(right).peel_refs().is_integral()
         // `1 << 0` is a common pattern in bit manipulation code
         && !(cmp == BinOpKind::Shl
-            && constant_simple(cx, cx.typeck_results(), right) == Some(Constant::Int(0))
+            && ConstEvalCtxt::new(cx).eval_simple(right) == Some(Constant::Int(0))
-            && constant_simple(cx, cx.typeck_results(), left) == Some(Constant::Int(1)))
+            && ConstEvalCtxt::new(cx).eval_simple(left) == Some(Constant::Int(1)))
 }
 
 fn check_remainder(cx: &LateContext<'_>, left: &Expr<'_>, right: &Expr<'_>, span: Span, arg: Span) {
-    let lhs_const = constant_full_int(cx, cx.typeck_results(), left);
+    let ecx = ConstEvalCtxt::new(cx);
-    let rhs_const = constant_full_int(cx, cx.typeck_results(), right);
+    if match (ecx.eval_full_int(left), ecx.eval_full_int(right)) {
-    if match (lhs_const, rhs_const) {
         (Some(FullInt::S(lv)), Some(FullInt::S(rv))) => lv.abs() < rv.abs(),
         (Some(FullInt::U(lv)), Some(FullInt::U(rv))) => lv < rv,
         _ => return,
@@ -201,7 +200,7 @@ fn check_remainder(cx: &LateContext<'_>, left: &Expr<'_>, right: &Expr<'_>, span
 }
 
 fn check_op(cx: &LateContext<'_>, e: &Expr<'_>, m: i8, span: Span, arg: Span, parens: Parens, is_erased: bool) -> bool {
-    if let Some(Constant::Int(v)) = constant_simple(cx, cx.typeck_results(), e).map(Constant::peel_refs) {
+    if let Some(Constant::Int(v)) = ConstEvalCtxt::new(cx).eval_simple(e).map(Constant::peel_refs) {
         let check = match *cx.typeck_results().expr_ty(e).peel_refs().kind() {
             ty::Int(ity) => unsext(cx.tcx, -1_i128, ity),
             ty::Uint(uty) => clip(cx.tcx, !0, uty),

clippy_lints/src/operators/modulo_arithmetic.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::sext;
 use rustc_hir::{BinOpKind, Expr, ExprKind, Node};
@@ -42,15 +42,11 @@ fn used_in_comparison_with_zero(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
     };
 
     if op.node == BinOpKind::Eq || op.node == BinOpKind::Ne {
-        if let Some(Constant::Int(0)) = constant(cx, cx.typeck_results(), rhs) {
+        let ecx = ConstEvalCtxt::new(cx);
-            return true;
+        matches!(ecx.eval(lhs), Some(Constant::Int(0))) || matches!(ecx.eval(rhs), Some(Constant::Int(0)))
-        }
+    } else {
-        if let Some(Constant::Int(0)) = constant(cx, cx.typeck_results(), lhs) {
+        false
-            return true;
-        }
     }
-
-    false
 }
 
 struct OperandInfo {
@@ -60,7 +56,7 @@ struct OperandInfo {
 }
 
 fn analyze_operand(operand: &Expr<'_>, cx: &LateContext<'_>, expr: &Expr<'_>) -> Option<OperandInfo> {
-    match constant(cx, cx.typeck_results(), operand) {
+    match ConstEvalCtxt::new(cx).eval(operand) {
         Some(Constant::Int(v)) => match *cx.typeck_results().expr_ty(expr).kind() {
             ty::Int(ity) => {
                 let value = sext(cx.tcx, v, ity);

clippy_lints/src/operators/numeric_arithmetic.rs

@@ -1,5 +1,5 @@
 use super::FLOAT_ARITHMETIC;
-use clippy_utils::consts::constant_simple;
+use clippy_utils::consts::ConstEvalCtxt;
 use clippy_utils::diagnostics::span_lint;
 use rustc_hir as hir;
 use rustc_lint::LateContext;
@@ -55,7 +55,7 @@ impl Context {
             return;
         }
         let ty = cx.typeck_results().expr_ty(arg);
-        if constant_simple(cx, cx.typeck_results(), expr).is_none() && ty.is_floating_point() {
+        if ConstEvalCtxt::new(cx).eval_simple(expr).is_none() && ty.is_floating_point() {
             span_lint(cx, FLOAT_ARITHMETIC, expr.span, "floating-point arithmetic detected");
             self.expr_id = Some(expr.hir_id);
         }

clippy_lints/src/ranges.rs

@@ -1,6 +1,6 @@
 use clippy_config::msrvs::{self, Msrv};
 use clippy_config::Conf;
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::{span_lint, span_lint_and_sugg, span_lint_and_then};
 use clippy_utils::source::{snippet, snippet_with_applicability, SpanRangeExt};
 use clippy_utils::sugg::Sugg;
@@ -319,7 +319,7 @@ fn check_range_bounds<'a, 'tcx>(cx: &'a LateContext<'tcx>, ex: &'a Expr<'_>) ->
             _ => return None,
         };
         if let Some(id) = path_to_local(l) {
-            if let Some(c) = constant(cx, cx.typeck_results(), r) {
+            if let Some(c) = ConstEvalCtxt::new(cx).eval(r) {
                 return Some(RangeBounds {
                     val: c,
                     expr: r,
@@ -331,7 +331,7 @@ fn check_range_bounds<'a, 'tcx>(cx: &'a LateContext<'tcx>, ex: &'a Expr<'_>) ->
                 });
             }
         } else if let Some(id) = path_to_local(r) {
-            if let Some(c) = constant(cx, cx.typeck_results(), l) {
+            if let Some(c) = ConstEvalCtxt::new(cx).eval(l) {
                 return Some(RangeBounds {
                     val: c,
                     expr: l,
@@ -451,8 +451,9 @@ fn check_reversed_empty_range(cx: &LateContext<'_>, expr: &Expr<'_>) {
     }) = higher::Range::hir(expr)
         && let ty = cx.typeck_results().expr_ty(start)
         && let ty::Int(_) | ty::Uint(_) = ty.kind()
-        && let Some(start_idx) = constant(cx, cx.typeck_results(), start)
+        && let ecx = ConstEvalCtxt::new(cx)
-        && let Some(end_idx) = constant(cx, cx.typeck_results(), end)
+        && let Some(start_idx) = ecx.eval(start)
+        && let Some(end_idx) = ecx.eval(end)
         && let Some(ordering) = Constant::partial_cmp(cx.tcx, ty, &start_idx, &end_idx)
         && is_empty_range(limits, ordering)
     {

clippy_lints/src/regex.rs

@@ -1,6 +1,6 @@
 use std::fmt::Display;
 
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::{span_lint, span_lint_and_help};
 use clippy_utils::source::snippet_opt;
 use clippy_utils::{def_path_def_ids, path_def_id, paths};
@@ -148,7 +148,7 @@ fn lint_syntax_error(cx: &LateContext<'_>, error: &regex_syntax::Error, unescape
 }
 
 fn const_str<'tcx>(cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) -> Option<String> {
-    constant(cx, cx.typeck_results(), e).and_then(|c| match c {
+    ConstEvalCtxt::new(cx).eval(e).and_then(|c| match c {
         Constant::Str(s) => Some(s),
         _ => None,
     })

clippy_lints/src/repeat_vec_with_capacity.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::higher::VecArgs;
 use clippy_utils::macros::matching_root_macro_call;
@@ -69,7 +69,7 @@ fn check_vec_macro(cx: &LateContext<'_>, expr: &Expr<'_>) {
         && let Some(VecArgs::Repeat(repeat_expr, len_expr)) = VecArgs::hir(cx, expr)
         && fn_def_id(cx, repeat_expr).is_some_and(|did| match_def_path(cx, did, &paths::VEC_WITH_CAPACITY))
         && !len_expr.span.from_expansion()
-        && let Some(Constant::Int(2..)) = constant(cx, cx.typeck_results(), expr_or_init(cx, len_expr))
+        && let Some(Constant::Int(2..)) = ConstEvalCtxt::new(cx).eval(expr_or_init(cx, len_expr))
     {
         emit_lint(
             cx,

clippy_lints/src/transmute/transmute_null_to_fn.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::{is_integer_literal, is_path_diagnostic_item};
 use rustc_hir::{Expr, ExprKind};
@@ -33,10 +33,7 @@ pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>, arg: &'t
         // Catching:
         // transmute over constants that resolve to `null`.
         ExprKind::Path(ref _qpath)
-            if matches!(
+            if matches!(ConstEvalCtxt::new(cx).eval(casts_peeled), Some(Constant::RawPtr(0))) =>
-                constant(cx, cx.typeck_results(), casts_peeled),
-                Some(Constant::RawPtr(0))
-            ) =>
         {
             lint_expr(cx, expr);
             true

clippy_lints/src/transmute/transmuting_null.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint;
 use clippy_utils::{is_integer_literal, is_path_diagnostic_item};
 use rustc_hir::{Expr, ExprKind};
@@ -17,7 +17,7 @@ pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>, arg: &'t
 
     // Catching transmute over constants that resolve to `null`.
     if let ExprKind::Path(ref _qpath) = arg.kind
-        && let Some(Constant::RawPtr(0)) = constant(cx, cx.typeck_results(), arg)
+        && let Some(Constant::RawPtr(0)) = ConstEvalCtxt::new(cx).eval(arg)
     {
         span_lint(cx, TRANSMUTING_NULL, expr.span, LINT_MSG);
         return true;

clippy_lints/src/utils/internal_lints/interning_defined_symbol.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant_simple, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::source::snippet;
 use clippy_utils::ty::match_type;
@@ -93,7 +93,7 @@ impl<'tcx> LateLintPass<'tcx> for InterningDefinedSymbol {
         if let ExprKind::Call(func, [arg]) = &expr.kind
             && let ty::FnDef(def_id, _) = cx.typeck_results().expr_ty(func).kind()
             && match_def_path(cx, *def_id, &paths::SYMBOL_INTERN)
-            && let Some(Constant::Str(arg)) = constant_simple(cx, cx.typeck_results(), arg)
+            && let Some(Constant::Str(arg)) = ConstEvalCtxt::new(cx).eval_simple(arg)
             && let value = Symbol::intern(&arg).as_u32()
             && let Some(&def_id) = self.symbol_map.get(&value)
         {
@@ -199,7 +199,7 @@ impl InterningDefinedSymbol {
             });
         }
         // is a string constant
-        if let Some(Constant::Str(s)) = constant_simple(cx, cx.typeck_results(), expr) {
+        if let Some(Constant::Str(s)) = ConstEvalCtxt::new(cx).eval_simple(expr) {
             let value = Symbol::intern(&s).as_u32();
             // ...which matches a symbol constant
             if let Some(&def_id) = self.symbol_map.get(&value) {

clippy_lints/src/utils/internal_lints/invalid_paths.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant_simple, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::def_path_res;
 use clippy_utils::diagnostics::span_lint;
 use rustc_hir as hir;
@@ -32,9 +32,9 @@ impl<'tcx> LateLintPass<'tcx> for InvalidPaths {
         let mod_name = &cx.tcx.item_name(local_def_id.to_def_id());
         if mod_name.as_str() == "paths"
             && let hir::ItemKind::Const(.., body_id) = item.kind
-            && let body = cx.tcx.hir().body(body_id)
+            && let Some(Constant::Vec(path)) =
-            && let typeck_results = cx.tcx.typeck_body(body_id)
+                ConstEvalCtxt::with_env(cx.tcx, cx.tcx.param_env(item.owner_id), cx.tcx.typeck(item.owner_id))
-            && let Some(Constant::Vec(path)) = constant_simple(cx, typeck_results, body.value)
+                    .eval_simple(cx.tcx.hir().body(body_id).value)
             && let Some(path) = path
                 .iter()
                 .map(|x| {

clippy_lints/src/vec.rs

@@ -3,7 +3,7 @@ use std::ops::ControlFlow;
 
 use clippy_config::msrvs::{self, Msrv};
 use clippy_config::Conf;
-use clippy_utils::consts::{constant, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_hir_and_then;
 use clippy_utils::source::snippet_opt;
 use clippy_utils::ty::is_copy;
@@ -159,7 +159,7 @@ impl UselessVec {
 
         let snippet = match *vec_args {
             higher::VecArgs::Repeat(elem, len) => {
-                if let Some(Constant::Int(len_constant)) = constant(cx, cx.typeck_results(), len) {
+                if let Some(Constant::Int(len_constant)) = ConstEvalCtxt::new(cx).eval(len) {
                     // vec![ty; N] works when ty is Clone, [ty; N] requires it to be Copy also
                     if !is_copy(cx, cx.typeck_results().expr_ty(elem)) {
                         return;

clippy_lints/src/zero_div_zero.rs

@@ -1,4 +1,4 @@
-use clippy_utils::consts::{constant_simple, Constant};
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
 use clippy_utils::diagnostics::span_lint_and_help;
 use rustc_hir::{BinOpKind, Expr, ExprKind};
 use rustc_lint::{LateContext, LateLintPass};
@@ -36,8 +36,9 @@ impl<'tcx> LateLintPass<'tcx> for ZeroDiv {
             // TODO - constant_simple does not fold many operations involving floats.
             // That's probably fine for this lint - it's pretty unlikely that someone would
             // do something like 0.0/(2.0 - 2.0), but it would be nice to warn on that case too.
-            && let Some(lhs_value) = constant_simple(cx, cx.typeck_results(), left)
+            && let ecx = ConstEvalCtxt::new(cx)
-            && let Some(rhs_value) = constant_simple(cx, cx.typeck_results(), right)
+            && let Some(lhs_value) = ecx.eval_simple(left)
+            && let Some(rhs_value) = ecx.eval_simple(right)
             // FIXME(f16_f128): add these types when eq is available on all platforms
             && (Constant::F32(0.0) == lhs_value || Constant::F64(0.0) == lhs_value)
             && (Constant::F32(0.0) == rhs_value || Constant::F64(0.0) == rhs_value)

clippy_utils/src/consts.rs

@@ -14,12 +14,13 @@ use rustc_lexer::tokenize;
 use rustc_lint::LateContext;
 use rustc_middle::mir::interpret::{alloc_range, Scalar};
 use rustc_middle::mir::ConstValue;
-use rustc_middle::ty::{self, EarlyBinder, FloatTy, GenericArgsRef, IntTy, List, ScalarInt, Ty, TyCtxt, UintTy};
+use rustc_middle::ty::{self, FloatTy, IntTy, ParamEnv, ScalarInt, Ty, TyCtxt, TypeckResults, UintTy};
 use rustc_middle::{bug, mir, span_bug};
 use rustc_span::def_id::DefId;
-use rustc_span::symbol::{Ident, Symbol};
+use rustc_span::symbol::Ident;
 use rustc_span::{sym, SyntaxContext};
 use rustc_target::abi::Size;
+use std::cell::Cell;
 use std::cmp::Ordering;
 use std::hash::{Hash, Hasher};
 use std::iter;
@@ -263,10 +264,10 @@ impl<'tcx> Constant<'tcx> {
     }
 
     /// Returns the integer value or `None` if `self` or `val_type` is not integer type.
-    pub fn int_value(&self, cx: &LateContext<'_>, val_type: Ty<'_>) -> Option<FullInt> {
+    pub fn int_value(&self, tcx: TyCtxt<'_>, val_type: Ty<'_>) -> Option<FullInt> {
         if let Constant::Int(const_int) = *self {
             match *val_type.kind() {
-                ty::Int(ity) => Some(FullInt::S(sext(cx.tcx, const_int, ity))),
+                ty::Int(ity) => Some(FullInt::S(sext(tcx, const_int, ity))),
                 ty::Uint(_) => Some(FullInt::U(const_int)),
                 _ => None,
             }
@@ -322,6 +323,7 @@ pub fn lit_to_mir_constant<'tcx>(lit: &LitKind, ty: Option<Ty<'tcx>>) -> Constan
 }
 
 /// The source of a constant value.
+#[derive(Clone, Copy)]
 pub enum ConstantSource {
     /// The value is determined solely from the expression.
     Local,
@@ -331,54 +333,11 @@ pub enum ConstantSource {
     CoreConstant,
 }
 impl ConstantSource {
-    pub fn is_local(&self) -> bool {
+    pub fn is_local(self) -> bool {
         matches!(self, Self::Local)
     }
 }
 
-/// Attempts to check whether the expression is a constant representing an empty slice, str, array,
-/// etc…
-pub fn constant_is_empty(lcx: &LateContext<'_>, e: &Expr<'_>) -> Option<bool> {
-    ConstEvalLateContext::new(lcx, lcx.typeck_results()).expr_is_empty(e)
-}
-
-/// Attempts to evaluate the expression as a constant.
-pub fn constant<'tcx>(
-    lcx: &LateContext<'tcx>,
-    typeck_results: &ty::TypeckResults<'tcx>,
-    e: &Expr<'_>,
-) -> Option<Constant<'tcx>> {
-    ConstEvalLateContext::new(lcx, typeck_results).expr(e)
-}
-
-/// Attempts to evaluate the expression as a constant.
-pub fn constant_with_source<'tcx>(
-    lcx: &LateContext<'tcx>,
-    typeck_results: &ty::TypeckResults<'tcx>,
-    e: &Expr<'_>,
-) -> Option<(Constant<'tcx>, ConstantSource)> {
-    let mut ctxt = ConstEvalLateContext::new(lcx, typeck_results);
-    let res = ctxt.expr(e);
-    res.map(|x| (x, ctxt.source))
-}
-
-/// Attempts to evaluate an expression only if its value is not dependent on other items.
-pub fn constant_simple<'tcx>(
-    lcx: &LateContext<'tcx>,
-    typeck_results: &ty::TypeckResults<'tcx>,
-    e: &Expr<'_>,
-) -> Option<Constant<'tcx>> {
-    constant_with_source(lcx, typeck_results, e).and_then(|(c, s)| s.is_local().then_some(c))
-}
-
-pub fn constant_full_int<'tcx>(
-    lcx: &LateContext<'tcx>,
-    typeck_results: &ty::TypeckResults<'tcx>,
-    e: &Expr<'_>,
-) -> Option<FullInt> {
-    constant_simple(lcx, typeck_results, e)?.int_value(lcx, typeck_results.expr_ty(e))
-}
-
 #[derive(Copy, Clone, Debug, Eq)]
 pub enum FullInt {
     S(i128),
@@ -417,44 +376,87 @@ impl Ord for FullInt {
     }
 }
 
-pub struct ConstEvalLateContext<'a, 'tcx> {
+/// The context required to evaluate a constant expression.
-    lcx: &'a LateContext<'tcx>,
+///
-    typeck_results: &'a ty::TypeckResults<'tcx>,
+/// This is currently limited to constant folding and reading the value of named constants.
-    param_env: ty::ParamEnv<'tcx>,
+pub struct ConstEvalCtxt<'tcx> {
-    source: ConstantSource,
+    tcx: TyCtxt<'tcx>,
-    args: GenericArgsRef<'tcx>,
+    param_env: ParamEnv<'tcx>,
+    typeck: &'tcx TypeckResults<'tcx>,
+    source: Cell<ConstantSource>,
 }
 
-impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
+impl<'tcx> ConstEvalCtxt<'tcx> {
-    pub fn new(lcx: &'a LateContext<'tcx>, typeck_results: &'a ty::TypeckResults<'tcx>) -> Self {
+    /// Creates the evaluation context from the lint context. This requires the lint context to be
+    /// in a body (i.e. `cx.enclosing_body.is_some()`).
+    pub fn new(cx: &LateContext<'tcx>) -> Self {
         Self {
-            lcx,
+            tcx: cx.tcx,
-            typeck_results,
+            param_env: cx.param_env,
-            param_env: lcx.param_env,
+            typeck: cx.typeck_results(),
-            source: ConstantSource::Local,
+            source: Cell::new(ConstantSource::Local),
-            args: List::empty(),
+        }
+    }
+
+    /// Creates an evaluation context.
+    pub fn with_env(tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>, typeck: &'tcx TypeckResults<'tcx>) -> Self {
+        Self {
+            tcx,
+            param_env,
+            typeck,
+            source: Cell::new(ConstantSource::Local),
+        }
+    }
+
+    /// Attempts to evaluate the expression and returns both the value and whether it's dependant on
+    /// other items.
+    pub fn eval_with_source(&self, e: &Expr<'_>) -> Option<(Constant<'tcx>, ConstantSource)> {
+        self.source.set(ConstantSource::Local);
+        self.expr(e).map(|c| (c, self.source.get()))
+    }
+
+    /// Attempts to evaluate the expression.
+    pub fn eval(&self, e: &Expr<'_>) -> Option<Constant<'tcx>> {
+        self.expr(e)
+    }
+
+    /// Attempts to evaluate the expression without accessing other items.
+    pub fn eval_simple(&self, e: &Expr<'_>) -> Option<Constant<'tcx>> {
+        match self.eval_with_source(e) {
+            Some((x, ConstantSource::Local)) => Some(x),
+            _ => None,
+        }
+    }
+
+    /// Attempts to evaluate the expression as an integer without accessing other items.
+    pub fn eval_full_int(&self, e: &Expr<'_>) -> Option<FullInt> {
+        match self.eval_with_source(e) {
+            Some((x, ConstantSource::Local)) => x.int_value(self.tcx, self.typeck.expr_ty(e)),
+            _ => None,
         }
     }
 
     /// Simple constant folding: Insert an expression, get a constant or none.
-    pub fn expr(&mut self, e: &Expr<'_>) -> Option<Constant<'tcx>> {
+    fn expr(&self, e: &Expr<'_>) -> Option<Constant<'tcx>> {
         match e.kind {
-            ExprKind::ConstBlock(ConstBlock { body, .. }) => self.expr(self.lcx.tcx.hir().body(body).value),
+            ExprKind::ConstBlock(ConstBlock { body, .. }) => self.expr(self.tcx.hir().body(body).value),
             ExprKind::DropTemps(e) => self.expr(e),
             ExprKind::Path(ref qpath) => {
-                let is_core_crate = if let Some(def_id) = self.lcx.qpath_res(qpath, e.hir_id()).opt_def_id() {
+                let is_core_crate = if let Some(def_id) = self.typeck.qpath_res(qpath, e.hir_id()).opt_def_id() {
-                    self.lcx.tcx.crate_name(def_id.krate) == sym::core
+                    self.tcx.crate_name(def_id.krate) == sym::core
                 } else {
                     false
                 };
-                self.fetch_path_and_apply(qpath, e.hir_id, self.typeck_results.expr_ty(e), |this, result| {
+                self.fetch_path_and_apply(qpath, e.hir_id, self.typeck.expr_ty(e), |self_, result| {
-                    let result = mir_to_const(this.lcx, result)?;
+                    let result = mir_to_const(self_.tcx, result)?;
                     // If source is already Constant we wouldn't want to override it with CoreConstant
-                    this.source = if is_core_crate && !matches!(this.source, ConstantSource::Constant) {
+                    self_.source.set(
-                        ConstantSource::CoreConstant
+                        if is_core_crate && !matches!(self_.source.get(), ConstantSource::Constant) {
-                    } else {
+                            ConstantSource::CoreConstant
-                        ConstantSource::Constant
+                        } else {
-                    };
+                            ConstantSource::Constant
+                        },
+                    );
                     Some(result)
                 })
             },
@@ -463,21 +465,21 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
                 if is_direct_expn_of(e.span, "cfg").is_some() {
                     None
                 } else {
-                    Some(lit_to_mir_constant(&lit.node, self.typeck_results.expr_ty_opt(e)))
+                    Some(lit_to_mir_constant(&lit.node, self.typeck.expr_ty_opt(e)))
                 }
             },
             ExprKind::Array(vec) => self.multi(vec).map(Constant::Vec),
             ExprKind::Tup(tup) => self.multi(tup).map(Constant::Tuple),
             ExprKind::Repeat(value, _) => {
-                let n = match self.typeck_results.expr_ty(e).kind() {
+                let n = match self.typeck.expr_ty(e).kind() {
-                    ty::Array(_, n) => n.try_eval_target_usize(self.lcx.tcx, self.lcx.param_env)?,
+                    ty::Array(_, n) => n.try_eval_target_usize(self.tcx, self.param_env)?,
                     _ => span_bug!(e.span, "typeck error"),
                 };
                 self.expr(value).map(|v| Constant::Repeat(Box::new(v), n))
             },
             ExprKind::Unary(op, operand) => self.expr(operand).and_then(|o| match op {
-                UnOp::Not => self.constant_not(&o, self.typeck_results.expr_ty(e)),
+                UnOp::Not => self.constant_not(&o, self.typeck.expr_ty(e)),
-                UnOp::Neg => self.constant_negate(&o, self.typeck_results.expr_ty(e)),
+                UnOp::Neg => self.constant_negate(&o, self.typeck.expr_ty(e)),
                 UnOp::Deref => Some(if let Constant::Ref(r) = o { *r } else { o }),
             }),
             ExprKind::If(cond, then, ref otherwise) => self.ifthenelse(cond, then, *otherwise),
@@ -486,21 +488,16 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
                 // We only handle a few const functions for now.
                 if args.is_empty()
                     && let ExprKind::Path(qpath) = &callee.kind
-                    && let res = self.typeck_results.qpath_res(qpath, callee.hir_id)
+                    && let Some(did) = self.typeck.qpath_res(qpath, callee.hir_id).opt_def_id()
-                    && let Some(def_id) = res.opt_def_id()
-                    && let def_path = self.lcx.get_def_path(def_id)
-                    && let def_path = def_path.iter().take(4).map(Symbol::as_str).collect::<Vec<_>>()
-                    && let ["core", "num", int_impl, "max_value"] = *def_path
                 {
-                    let value = match int_impl {
+                    match self.tcx.get_diagnostic_name(did) {
-                        "<impl i8>" => i8::MAX as u128,
+                        Some(sym::i8_legacy_fn_max_value) => Some(Constant::Int(i8::MAX as u128)),
-                        "<impl i16>" => i16::MAX as u128,
+                        Some(sym::i16_legacy_fn_max_value) => Some(Constant::Int(i16::MAX as u128)),
-                        "<impl i32>" => i32::MAX as u128,
+                        Some(sym::i32_legacy_fn_max_value) => Some(Constant::Int(i32::MAX as u128)),
-                        "<impl i64>" => i64::MAX as u128,
+                        Some(sym::i64_legacy_fn_max_value) => Some(Constant::Int(i64::MAX as u128)),
-                        "<impl i128>" => i128::MAX as u128,
+                        Some(sym::i128_legacy_fn_max_value) => Some(Constant::Int(i128::MAX as u128)),
-                        _ => return None,
+                        _ => None,
-                    };
+                    }
-                    Some(Constant::Int(value))
                 } else {
                     None
                 }
@@ -512,9 +509,9 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
                 if let Some(Constant::Adt(constant)) = &self.expr(local_expr)
                     && let ty::Adt(adt_def, _) = constant.ty().kind()
                     && adt_def.is_struct()
-                    && let Some(desired_field) = field_of_struct(*adt_def, self.lcx, *constant, field)
+                    && let Some(desired_field) = field_of_struct(*adt_def, self.tcx, *constant, field)
                 {
-                    mir_to_const(self.lcx, desired_field)
+                    mir_to_const(self.tcx, desired_field)
                 } else {
                     result
                 }
@@ -526,21 +523,21 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
     /// Simple constant folding to determine if an expression is an empty slice, str, array, …
     /// `None` will be returned if the constness cannot be determined, or if the resolution
     /// leaves the local crate.
-    pub fn expr_is_empty(&mut self, e: &Expr<'_>) -> Option<bool> {
+    pub fn eval_is_empty(&self, e: &Expr<'_>) -> Option<bool> {
         match e.kind {
-            ExprKind::ConstBlock(ConstBlock { body, .. }) => self.expr_is_empty(self.lcx.tcx.hir().body(body).value),
+            ExprKind::ConstBlock(ConstBlock { body, .. }) => self.eval_is_empty(self.tcx.hir().body(body).value),
-            ExprKind::DropTemps(e) => self.expr_is_empty(e),
+            ExprKind::DropTemps(e) => self.eval_is_empty(e),
             ExprKind::Path(ref qpath) => {
                 if !self
-                    .typeck_results
+                    .typeck
                     .qpath_res(qpath, e.hir_id)
                     .opt_def_id()
                     .is_some_and(DefId::is_local)
                 {
                     return None;
                 }
-                self.fetch_path_and_apply(qpath, e.hir_id, self.typeck_results.expr_ty(e), |this, result| {
+                self.fetch_path_and_apply(qpath, e.hir_id, self.typeck.expr_ty(e), |self_, result| {
-                    mir_is_empty(this.lcx, result)
+                    mir_is_empty(self_.tcx, result)
                 })
             },
             ExprKind::Lit(lit) => {
@@ -556,8 +553,8 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
             },
             ExprKind::Array(vec) => self.multi(vec).map(|v| v.is_empty()),
             ExprKind::Repeat(..) => {
-                if let ty::Array(_, n) = self.typeck_results.expr_ty(e).kind() {
+                if let ty::Array(_, n) = self.typeck.expr_ty(e).kind() {
-                    Some(n.try_eval_target_usize(self.lcx.tcx, self.lcx.param_env)? == 0)
+                    Some(n.try_eval_target_usize(self.tcx, self.param_env)? == 0)
                 } else {
                     span_bug!(e.span, "typeck error");
                 }
@@ -574,8 +571,8 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
             Int(value) => {
                 let value = !value;
                 match *ty.kind() {
-                    ty::Int(ity) => Some(Int(unsext(self.lcx.tcx, value as i128, ity))),
+                    ty::Int(ity) => Some(Int(unsext(self.tcx, value as i128, ity))),
-                    ty::Uint(ity) => Some(Int(clip(self.lcx.tcx, value, ity))),
+                    ty::Uint(ity) => Some(Int(clip(self.tcx, value, ity))),
                     _ => None,
                 }
             },
@@ -590,7 +587,7 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
                 let ty::Int(ity) = *ty.kind() else { return None };
                 let (min, _) = ity.min_max()?;
                 // sign extend
-                let value = sext(self.lcx.tcx, value, ity);
+                let value = sext(self.tcx, value, ity);
 
                 // Applying unary - to the most negative value of any signed integer type panics.
                 if value == min {
@@ -599,7 +596,7 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
 
                 let value = value.checked_neg()?;
                 // clear unused bits
-                Some(Int(unsext(self.lcx.tcx, value, ity)))
+                Some(Int(unsext(self.tcx, value, ity)))
             },
             F32(f) => Some(F32(-f)),
             F64(f) => Some(F64(-f)),
@@ -609,21 +606,21 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
 
     /// Create `Some(Vec![..])` of all constants, unless there is any
     /// non-constant part.
-    fn multi(&mut self, vec: &[Expr<'_>]) -> Option<Vec<Constant<'tcx>>> {
+    fn multi(&self, vec: &[Expr<'_>]) -> Option<Vec<Constant<'tcx>>> {
         vec.iter().map(|elem| self.expr(elem)).collect::<Option<_>>()
     }
 
     /// Lookup a possibly constant expression from an `ExprKind::Path` and apply a function on it.
-    fn fetch_path_and_apply<T, F>(&mut self, qpath: &QPath<'_>, id: HirId, ty: Ty<'tcx>, f: F) -> Option<T>
+    fn fetch_path_and_apply<T, F>(&self, qpath: &QPath<'_>, id: HirId, ty: Ty<'tcx>, f: F) -> Option<T>
     where
-        F: FnOnce(&mut Self, mir::Const<'tcx>) -> Option<T>,
+        F: FnOnce(&Self, mir::Const<'tcx>) -> Option<T>,
     {
-        let res = self.typeck_results.qpath_res(qpath, id);
+        let res = self.typeck.qpath_res(qpath, id);
         match res {
             Res::Def(DefKind::Const | DefKind::AssocConst, def_id) => {
                 // Check if this constant is based on `cfg!(..)`,
                 // which is NOT constant for our purposes.
-                if let Some(node) = self.lcx.tcx.hir().get_if_local(def_id)
+                if let Some(node) = self.tcx.hir().get_if_local(def_id)
                     && let Node::Item(Item {
                         kind: ItemKind::Const(.., body_id),
                         ..
@@ -632,20 +629,14 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
                         kind: ExprKind::Lit(_),
                         span,
                         ..
-                    }) = self.lcx.tcx.hir_node(body_id.hir_id)
+                    }) = self.tcx.hir_node(body_id.hir_id)
                     && is_direct_expn_of(*span, "cfg").is_some()
                 {
                     return None;
                 }
 
-                let args = self.typeck_results.node_args(id);
+                let args = self.typeck.node_args(id);
-                let args = if self.args.is_empty() {
-                    args
-                } else {
-                    EarlyBinder::bind(args).instantiate(self.lcx.tcx, self.args)
-                };
                 let result = self
-                    .lcx
                     .tcx
                     .const_eval_resolve(self.param_env, mir::UnevaluatedConst::new(def_id, args), qpath.span())
                     .ok()
@@ -656,7 +647,7 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
         }
     }
 
-    fn index(&mut self, lhs: &'_ Expr<'_>, index: &'_ Expr<'_>) -> Option<Constant<'tcx>> {
+    fn index(&self, lhs: &'_ Expr<'_>, index: &'_ Expr<'_>) -> Option<Constant<'tcx>> {
         let lhs = self.expr(lhs);
         let index = self.expr(index);
 
@@ -685,8 +676,8 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
         }
     }
 
-    /// A block can only yield a constant if it only has one constant expression.
+    /// A block can only yield a constant if it has exactly one constant expression.
-    fn block(&mut self, block: &Block<'_>) -> Option<Constant<'tcx>> {
+    fn block(&self, block: &Block<'_>) -> Option<Constant<'tcx>> {
         if block.stmts.is_empty()
             && let Some(expr) = block.expr
         {
@@ -696,7 +687,7 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
                 if let Some(expr_span) = walk_span_to_context(expr.span, span.ctxt)
                     && let expr_lo = expr_span.lo()
                     && expr_lo >= span.lo
-                    && let Some(src) = (span.lo..expr_lo).get_source_text(self.lcx)
+                    && let Some(src) = (span.lo..expr_lo).get_source_text(&self.tcx)
                     && let Some(src) = src.as_str()
                 {
                     use rustc_lexer::TokenKind::{BlockComment, LineComment, OpenBrace, Semi, Whitespace};
@@ -705,11 +696,11 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
                         .filter(|t| !matches!(t, Whitespace | LineComment { .. } | BlockComment { .. } | Semi))
                         .eq([OpenBrace])
                     {
-                        self.source = ConstantSource::Constant;
+                        self.source.set(ConstantSource::Constant);
                     }
                 } else {
                     // Unable to access the source. Assume a non-local dependency.
-                    self.source = ConstantSource::Constant;
+                    self.source.set(ConstantSource::Constant);
                 }
             }
 
@@ -719,7 +710,7 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
         }
     }
 
-    fn ifthenelse(&mut self, cond: &Expr<'_>, then: &Expr<'_>, otherwise: Option<&Expr<'_>>) -> Option<Constant<'tcx>> {
+    fn ifthenelse(&self, cond: &Expr<'_>, then: &Expr<'_>, otherwise: Option<&Expr<'_>>) -> Option<Constant<'tcx>> {
         if let Some(Constant::Bool(b)) = self.expr(cond) {
             if b {
                 self.expr(then)
@@ -731,16 +722,16 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
         }
     }
 
-    fn binop(&mut self, op: BinOp, left: &Expr<'_>, right: &Expr<'_>) -> Option<Constant<'tcx>> {
+    fn binop(&self, op: BinOp, left: &Expr<'_>, right: &Expr<'_>) -> Option<Constant<'tcx>> {
         let l = self.expr(left)?;
         let r = self.expr(right);
         match (l, r) {
-            (Constant::Int(l), Some(Constant::Int(r))) => match *self.typeck_results.expr_ty_opt(left)?.kind() {
+            (Constant::Int(l), Some(Constant::Int(r))) => match *self.typeck.expr_ty_opt(left)?.kind() {
                 ty::Int(ity) => {
                     let (ty_min_value, _) = ity.min_max()?;
                     let bits = ity.bits();
-                    let l = sext(self.lcx.tcx, l, ity);
+                    let l = sext(self.tcx, l, ity);
-                    let r = sext(self.lcx.tcx, r, ity);
+                    let r = sext(self.tcx, r, ity);
 
                     // Using / or %, where the left-hand argument is the smallest integer of a signed integer type and
                     // the right-hand argument is -1 always panics, even with overflow-checks disabled
@@ -751,7 +742,7 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
                         return None;
                     }
 
-                    let zext = |n: i128| Constant::Int(unsext(self.lcx.tcx, n, ity));
+                    let zext = |n: i128| Constant::Int(unsext(self.tcx, n, ity));
                     match op.node {
                         // When +, * or binary - create a value greater than the maximum value, or less than
                         // the minimum value that can be stored, it panics.
@@ -845,7 +836,7 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
     }
 }
 
-pub fn mir_to_const<'tcx>(lcx: &LateContext<'tcx>, result: mir::Const<'tcx>) -> Option<Constant<'tcx>> {
+pub fn mir_to_const<'tcx>(tcx: TyCtxt<'tcx>, result: mir::Const<'tcx>) -> Option<Constant<'tcx>> {
     let mir::Const::Val(val, _) = result else {
         // We only work on evaluated consts.
         return None;
@@ -863,13 +854,13 @@ pub fn mir_to_const<'tcx>(lcx: &LateContext<'tcx>, result: mir::Const<'tcx>) ->
             _ => None,
         },
         (_, ty::Ref(_, inner_ty, _)) if matches!(inner_ty.kind(), ty::Str) => {
-            let data = val.try_get_slice_bytes_for_diagnostics(lcx.tcx)?;
+            let data = val.try_get_slice_bytes_for_diagnostics(tcx)?;
             String::from_utf8(data.to_owned()).ok().map(Constant::Str)
         },
         (_, ty::Adt(adt_def, _)) if adt_def.is_struct() => Some(Constant::Adt(result)),
         (ConstValue::Indirect { alloc_id, offset }, ty::Array(sub_type, len)) => {
-            let alloc = lcx.tcx.global_alloc(alloc_id).unwrap_memory().inner();
+            let alloc = tcx.global_alloc(alloc_id).unwrap_memory().inner();
-            let len = len.try_to_target_usize(lcx.tcx)?;
+            let len = len.try_to_target_usize(tcx)?;
             let ty::Float(flt) = sub_type.kind() else {
                 return None;
             };
@@ -877,7 +868,7 @@ pub fn mir_to_const<'tcx>(lcx: &LateContext<'tcx>, result: mir::Const<'tcx>) ->
             let mut res = Vec::new();
             for idx in 0..len {
                 let range = alloc_range(offset + size * idx, size);
-                let val = alloc.read_scalar(&lcx.tcx, range, /* read_provenance */ false).ok()?;
+                let val = alloc.read_scalar(&tcx, range, /* read_provenance */ false).ok()?;
                 res.push(match flt {
                     FloatTy::F16 => Constant::F16(f16::from_bits(val.to_u16().ok()?)),
                     FloatTy::F32 => Constant::F32(f32::from_bits(val.to_u32().ok()?)),
@@ -891,7 +882,7 @@ pub fn mir_to_const<'tcx>(lcx: &LateContext<'tcx>, result: mir::Const<'tcx>) ->
     }
 }
 
-fn mir_is_empty<'tcx>(lcx: &LateContext<'tcx>, result: mir::Const<'tcx>) -> Option<bool> {
+fn mir_is_empty<'tcx>(tcx: TyCtxt<'tcx>, result: mir::Const<'tcx>) -> Option<bool> {
     let mir::Const::Val(val, _) = result else {
         // We only work on evaluated consts.
         return None;
@@ -902,26 +893,26 @@ fn mir_is_empty<'tcx>(lcx: &LateContext<'tcx>, result: mir::Const<'tcx>) -> Opti
                 if let ConstValue::Indirect { alloc_id, offset } = val {
                     // Get the length from the slice, using the same formula as
                     // [`ConstValue::try_get_slice_bytes_for_diagnostics`].
-                    let a = lcx.tcx.global_alloc(alloc_id).unwrap_memory().inner();
+                    let a = tcx.global_alloc(alloc_id).unwrap_memory().inner();
-                    let ptr_size = lcx.tcx.data_layout.pointer_size;
+                    let ptr_size = tcx.data_layout.pointer_size;
                     if a.size() < offset + 2 * ptr_size {
                         // (partially) dangling reference
                         return None;
                     }
                     let len = a
-                        .read_scalar(&lcx.tcx, alloc_range(offset + ptr_size, ptr_size), false)
+                        .read_scalar(&tcx, alloc_range(offset + ptr_size, ptr_size), false)
                         .ok()?
-                        .to_target_usize(&lcx.tcx)
+                        .to_target_usize(&tcx)
                         .ok()?;
                     Some(len == 0)
                 } else {
                     None
                 }
             },
-            ty::Array(_, len) => Some(len.try_to_target_usize(lcx.tcx)? == 0),
+            ty::Array(_, len) => Some(len.try_to_target_usize(tcx)? == 0),
             _ => None,
         },
-        (ConstValue::Indirect { .. }, ty::Array(_, len)) => Some(len.try_to_target_usize(lcx.tcx)? == 0),
+        (ConstValue::Indirect { .. }, ty::Array(_, len)) => Some(len.try_to_target_usize(tcx)? == 0),
         (ConstValue::ZeroSized, _) => Some(true),
         _ => None,
     }
@@ -929,12 +920,12 @@ fn mir_is_empty<'tcx>(lcx: &LateContext<'tcx>, result: mir::Const<'tcx>) -> Opti
 
 fn field_of_struct<'tcx>(
     adt_def: ty::AdtDef<'tcx>,
-    lcx: &LateContext<'tcx>,
+    tcx: TyCtxt<'tcx>,
     result: mir::Const<'tcx>,
     field: &Ident,
 ) -> Option<mir::Const<'tcx>> {
     if let mir::Const::Val(result, ty) = result
-        && let Some(dc) = lcx.tcx.try_destructure_mir_constant_for_user_output(result, ty)
+        && let Some(dc) = tcx.try_destructure_mir_constant_for_user_output(result, ty)
         && let Some(dc_variant) = dc.variant
         && let Some(variant) = adt_def.variants().get(dc_variant)
         && let Some(field_idx) = variant.fields.iter().position(|el| el.name == field.name)

clippy_utils/src/eager_or_lazy.rs

@@ -9,7 +9,7 @@
 //!  - or-fun-call
 //!  - option-if-let-else
 
-use crate::consts::{constant, FullInt};
+use crate::consts::{ConstEvalCtxt, FullInt};
 use crate::ty::{all_predicates_of, is_copy};
 use crate::visitors::is_const_evaluatable;
 use rustc_hir::def::{DefKind, Res};
@@ -206,7 +206,7 @@ fn expr_eagerness<'tcx>(cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) -> EagernessS
                 },
 
                 // `-i32::MIN` panics with overflow checks
-                ExprKind::Unary(UnOp::Neg, right) if constant(self.cx, self.cx.typeck_results(), right).is_none() => {
+                ExprKind::Unary(UnOp::Neg, right) if ConstEvalCtxt::new(self.cx).eval(right).is_none() => {
                     self.eagerness |= NoChange;
                 },
 
@@ -232,7 +232,7 @@ fn expr_eagerness<'tcx>(cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) -> EagernessS
                 // Thus, we would realistically only delay the lint.
                 ExprKind::Binary(op, _, right)
                     if matches!(op.node, BinOpKind::Shl | BinOpKind::Shr)
-                        && constant(self.cx, self.cx.typeck_results(), right).is_none() =>
+                        && ConstEvalCtxt::new(self.cx).eval(right).is_none() =>
                 {
                     self.eagerness |= NoChange;
                 },
@@ -240,9 +240,9 @@ fn expr_eagerness<'tcx>(cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) -> EagernessS
                 ExprKind::Binary(op, left, right)
                     if matches!(op.node, BinOpKind::Div | BinOpKind::Rem)
                         && let right_ty = self.cx.typeck_results().expr_ty(right)
-                        && let left = constant(self.cx, self.cx.typeck_results(), left)
+                        && let ecx = ConstEvalCtxt::new(self.cx)
-                        && let right = constant(self.cx, self.cx.typeck_results(), right)
+                        && let left = ecx.eval(left)
-                            .and_then(|c| c.int_value(self.cx, right_ty))
+                        && let right = ecx.eval(right).and_then(|c| c.int_value(self.cx.tcx, right_ty))
                         && matches!(
                             (left, right),
                             // `1 / x`: x might be zero
@@ -261,8 +261,8 @@ fn expr_eagerness<'tcx>(cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) -> EagernessS
                 ExprKind::Binary(op, left, right)
                     if matches!(op.node, BinOpKind::Add | BinOpKind::Sub | BinOpKind::Mul)
                         && !self.cx.typeck_results().expr_ty(e).is_floating_point()
-                        && (constant(self.cx, self.cx.typeck_results(), left).is_none()
+                        && let ecx = ConstEvalCtxt::new(self.cx)
-                            || constant(self.cx, self.cx.typeck_results(), right).is_none()) =>
+                        && (ecx.eval(left).is_none() || ecx.eval(right).is_none()) =>
                 {
                     self.eagerness |= NoChange;
                 },

clippy_utils/src/higher.rs

@@ -2,7 +2,7 @@
 
 #![deny(clippy::missing_docs_in_private_items)]
 
-use crate::consts::{constant_simple, Constant};
+use crate::consts::{ConstEvalCtxt, Constant};
 use crate::ty::is_type_diagnostic_item;
 use crate::{is_expn_of, match_def_path, paths};
 
@@ -471,7 +471,7 @@ pub fn get_vec_init_kind<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) -
                     return Some(VecInitKind::Default);
                 } else if name.ident.name.as_str() == "with_capacity" {
                     let arg = args.first()?;
-                    return match constant_simple(cx, cx.typeck_results(), arg) {
+                    return match ConstEvalCtxt::new(cx).eval_simple(arg) {
                         Some(Constant::Int(num)) => Some(VecInitKind::WithConstCapacity(num)),
                         _ => Some(VecInitKind::WithExprCapacity(arg.hir_id)),
                     };

clippy_utils/src/hir_utils.rs

@@ -1,4 +1,4 @@
-use crate::consts::constant_simple;
+use crate::consts::ConstEvalCtxt;
 use crate::macros::macro_backtrace;
 use crate::source::{snippet_opt, walk_span_to_context, SpanRange, SpanRangeExt};
 use crate::tokenize_with_text;
@@ -255,8 +255,8 @@ impl HirEqInterExpr<'_, '_, '_> {
         if let Some((typeck_lhs, typeck_rhs)) = self.inner.maybe_typeck_results
             && typeck_lhs.expr_ty(left) == typeck_rhs.expr_ty(right)
             && let (Some(l), Some(r)) = (
-                constant_simple(self.inner.cx, typeck_lhs, left),
+                ConstEvalCtxt::with_env(self.inner.cx.tcx, self.inner.cx.param_env, typeck_lhs).eval_simple(left),
-                constant_simple(self.inner.cx, typeck_rhs, right),
+                ConstEvalCtxt::with_env(self.inner.cx.tcx, self.inner.cx.param_env, typeck_rhs).eval_simple(right),
             )
             && l == r
         {
@@ -714,9 +714,9 @@ impl<'a, 'tcx> SpanlessHash<'a, 'tcx> {
 
     #[expect(clippy::too_many_lines)]
     pub fn hash_expr(&mut self, e: &Expr<'_>) {
-        let simple_const = self
+        let simple_const = self.maybe_typeck_results.and_then(|typeck_results| {
-            .maybe_typeck_results
+            ConstEvalCtxt::with_env(self.cx.tcx, self.cx.param_env, typeck_results).eval_simple(e)
-            .and_then(|typeck_results| constant_simple(self.cx, typeck_results, e));
+        });
 
         // const hashing may result in the same hash as some unrelated node, so add a sort of
         // discriminant depending on which path we're choosing next

clippy_utils/src/lib.rs

@@ -125,7 +125,7 @@ use rustc_span::{sym, Span};
 use rustc_target::abi::Integer;
 use visitors::Visitable;
 
-use crate::consts::{constant, mir_to_const, Constant};
+use crate::consts::{mir_to_const, ConstEvalCtxt, Constant};
 use crate::higher::Range;
 use crate::ty::{adt_and_variant_of_res, can_partially_move_ty, expr_sig, is_copy, is_recursively_primitive_type};
 use crate::visitors::for_each_expr_without_closures;
@@ -1581,8 +1581,8 @@ pub fn is_range_full(cx: &LateContext<'_>, expr: &Expr<'_>, container_path: Opti
             if let rustc_ty::Adt(_, subst) = ty.kind()
                 && let bnd_ty = subst.type_at(0)
                 && let Some(min_val) = bnd_ty.numeric_min_val(cx.tcx)
-                && let Some(min_const) = mir_to_const(cx, Const::from_ty_const(min_val, bnd_ty, cx.tcx))
+                && let Some(min_const) = mir_to_const(cx.tcx, Const::from_ty_const(min_val, bnd_ty, cx.tcx))
-                && let Some(start_const) = constant(cx, cx.typeck_results(), start)
+                && let Some(start_const) = ConstEvalCtxt::new(cx).eval(start)
             {
                 start_const == min_const
             } else {
@@ -1594,8 +1594,8 @@ pub fn is_range_full(cx: &LateContext<'_>, expr: &Expr<'_>, container_path: Opti
                 if let rustc_ty::Adt(_, subst) = ty.kind()
                     && let bnd_ty = subst.type_at(0)
                     && let Some(max_val) = bnd_ty.numeric_max_val(cx.tcx)
-                    && let Some(max_const) = mir_to_const(cx, Const::from_ty_const(max_val, bnd_ty, cx.tcx))
+                    && let Some(max_const) = mir_to_const(cx.tcx, Const::from_ty_const(max_val, bnd_ty, cx.tcx))
-                    && let Some(end_const) = constant(cx, cx.typeck_results(), end)
+                    && let Some(end_const) = ConstEvalCtxt::new(cx).eval(end)
                 {
                     end_const == max_const
                 } else {
@@ -1626,7 +1626,9 @@ pub fn is_integer_const(cx: &LateContext<'_>, e: &Expr<'_>, value: u128) -> bool
         return true;
     }
     let enclosing_body = cx.tcx.hir().enclosing_body_owner(e.hir_id);
-    if let Some(Constant::Int(v)) = constant(cx, cx.tcx.typeck(enclosing_body), e) {
+    if let Some(Constant::Int(v)) =
+        ConstEvalCtxt::with_env(cx.tcx, cx.tcx.param_env(enclosing_body), cx.tcx.typeck(enclosing_body)).eval(e)
+    {
         return value == v;
     }
     false

clippy_utils/src/source.rs

@@ -6,7 +6,8 @@ use rustc_ast::{LitKind, StrStyle};
 use rustc_data_structures::sync::Lrc;
 use rustc_errors::Applicability;
 use rustc_hir::{BlockCheckMode, Expr, ExprKind, UnsafeSource};
-use rustc_lint::{LateContext, LintContext};
+use rustc_lint::{EarlyContext, LateContext};
+use rustc_middle::ty::TyCtxt;
 use rustc_session::Session;
 use rustc_span::source_map::{original_sp, SourceMap};
 use rustc_span::{
@@ -17,6 +18,30 @@ use std::borrow::Cow;
 use std::fmt;
 use std::ops::Range;
 
+pub trait HasSession {
+    fn sess(&self) -> &Session;
+}
+impl HasSession for Session {
+    fn sess(&self) -> &Session {
+        self
+    }
+}
+impl HasSession for TyCtxt<'_> {
+    fn sess(&self) -> &Session {
+        self.sess
+    }
+}
+impl HasSession for EarlyContext<'_> {
+    fn sess(&self) -> &Session {
+        ::rustc_lint::LintContext::sess(self)
+    }
+}
+impl HasSession for LateContext<'_> {
+    fn sess(&self) -> &Session {
+        self.tcx.sess()
+    }
+}
+
 /// Conversion of a value into the range portion of a `Span`.
 pub trait SpanRange: Sized {
     fn into_range(self) -> Range<BytePos>;
@@ -71,19 +96,19 @@ impl IntoSpan for Range<BytePos> {
 pub trait SpanRangeExt: SpanRange {
     /// Gets the source file, and range in the file, of the given span. Returns `None` if the span
     /// extends through multiple files, or is malformed.
-    fn get_source_text(self, cx: &impl LintContext) -> Option<SourceFileRange> {
+    fn get_source_text(self, cx: &impl HasSession) -> Option<SourceFileRange> {
         get_source_text(cx.sess().source_map(), self.into_range())
     }
 
     /// Calls the given function with the source text referenced and returns the value. Returns
     /// `None` if the source text cannot be retrieved.
-    fn with_source_text<T>(self, cx: &impl LintContext, f: impl for<'a> FnOnce(&'a str) -> T) -> Option<T> {
+    fn with_source_text<T>(self, cx: &impl HasSession, f: impl for<'a> FnOnce(&'a str) -> T) -> Option<T> {
         with_source_text(cx.sess().source_map(), self.into_range(), f)
     }
 
     /// Checks if the referenced source text satisfies the given predicate. Returns `false` if the
     /// source text cannot be retrieved.
-    fn check_source_text(self, cx: &impl LintContext, pred: impl for<'a> FnOnce(&'a str) -> bool) -> bool {
+    fn check_source_text(self, cx: &impl HasSession, pred: impl for<'a> FnOnce(&'a str) -> bool) -> bool {
         self.with_source_text(cx, pred).unwrap_or(false)
     }
 
@@ -91,7 +116,7 @@ pub trait SpanRangeExt: SpanRange {
     /// and returns the value. Returns `None` if the source text cannot be retrieved.
     fn with_source_text_and_range<T>(
         self,
-        cx: &impl LintContext,
+        cx: &impl HasSession,
         f: impl for<'a> FnOnce(&'a str, Range<usize>) -> T,
     ) -> Option<T> {
         with_source_text_and_range(cx.sess().source_map(), self.into_range(), f)
@@ -104,30 +129,30 @@ pub trait SpanRangeExt: SpanRange {
     /// The new range must reside within the same source file.
     fn map_range(
         self,
-        cx: &impl LintContext,
+        cx: &impl HasSession,
         f: impl for<'a> FnOnce(&'a str, Range<usize>) -> Option<Range<usize>>,
     ) -> Option<Range<BytePos>> {
         map_range(cx.sess().source_map(), self.into_range(), f)
     }
 
     /// Extends the range to include all preceding whitespace characters.
-    fn with_leading_whitespace(self, cx: &impl LintContext) -> Range<BytePos> {
+    fn with_leading_whitespace(self, cx: &impl HasSession) -> Range<BytePos> {
         with_leading_whitespace(cx.sess().source_map(), self.into_range())
     }
 
     /// Trims the leading whitespace from the range.
-    fn trim_start(self, cx: &impl LintContext) -> Range<BytePos> {
+    fn trim_start(self, cx: &impl HasSession) -> Range<BytePos> {
         trim_start(cx.sess().source_map(), self.into_range())
     }
 
     /// Writes the referenced source text to the given writer. Will return `Err` if the source text
     /// could not be retrieved.
-    fn write_source_text_to(self, cx: &impl LintContext, dst: &mut impl fmt::Write) -> fmt::Result {
+    fn write_source_text_to(self, cx: &impl HasSession, dst: &mut impl fmt::Write) -> fmt::Result {
         write_source_text_to(cx.sess().source_map(), self.into_range(), dst)
     }
 
     /// Extracts the referenced source text as an owned string.
-    fn source_text_to_string(self, cx: &impl LintContext) -> Option<String> {
+    fn source_text_to_string(self, cx: &impl HasSession) -> Option<String> {
         self.with_source_text(cx, ToOwned::to_owned)
     }
 }
@@ -227,15 +252,15 @@ impl SourceFileRange {
 }
 
 /// Like `snippet_block`, but add braces if the expr is not an `ExprKind::Block`.
-pub fn expr_block<T: LintContext>(
+pub fn expr_block(
-    cx: &T,
+    sess: &impl HasSession,
     expr: &Expr<'_>,
     outer: SyntaxContext,
     default: &str,
     indent_relative_to: Option<Span>,
     app: &mut Applicability,
 ) -> String {
-    let (code, from_macro) = snippet_block_with_context(cx, expr.span, outer, default, indent_relative_to, app);
+    let (code, from_macro) = snippet_block_with_context(sess, expr.span, outer, default, indent_relative_to, app);
     if !from_macro
         && let ExprKind::Block(block, _) = expr.kind
         && block.rules != BlockCheckMode::UnsafeBlock(UnsafeSource::UserProvided)
@@ -260,13 +285,13 @@ pub fn expr_block<T: LintContext>(
 ///     let x = ();
 /// //  ^^^^^^^^^^
 /// ```
-pub fn first_line_of_span<T: LintContext>(cx: &T, span: Span) -> Span {
+pub fn first_line_of_span(sess: &impl HasSession, span: Span) -> Span {
-    first_char_in_first_line(cx, span).map_or(span, |first_char_pos| span.with_lo(first_char_pos))
+    first_char_in_first_line(sess, span).map_or(span, |first_char_pos| span.with_lo(first_char_pos))
 }
 
-fn first_char_in_first_line<T: LintContext>(cx: &T, span: Span) -> Option<BytePos> {
+fn first_char_in_first_line(sess: &impl HasSession, span: Span) -> Option<BytePos> {
-    let line_span = line_span(cx, span);
+    let line_span = line_span(sess, span);
-    snippet_opt(cx, line_span).and_then(|snip| {
+    snippet_opt(sess, line_span).and_then(|snip| {
         snip.find(|c: char| !c.is_whitespace())
             .map(|pos| line_span.lo() + BytePos::from_usize(pos))
     })
@@ -281,9 +306,9 @@ fn first_char_in_first_line<T: LintContext>(cx: &T, span: Span) -> Option<BytePo
 ///        let x = ();
 /// // ^^^^^^^^^^^^^^
 /// ```
-fn line_span<T: LintContext>(cx: &T, span: Span) -> Span {
+fn line_span(sess: &impl HasSession, span: Span) -> Span {
     let span = original_sp(span, DUMMY_SP);
-    let SourceFileAndLine { sf, line } = cx.sess().source_map().lookup_line(span.lo()).unwrap();
+    let SourceFileAndLine { sf, line } = sess.sess().source_map().lookup_line(span.lo()).unwrap();
     let line_start = sf.lines()[line];
     let line_start = sf.absolute_position(line_start);
     span.with_lo(line_start)
@@ -297,13 +322,13 @@ fn line_span<T: LintContext>(cx: &T, span: Span) -> Span {
 ///     let x = ();
 /// //          ^^ -- will return 4
 /// ```
-pub fn indent_of<T: LintContext>(cx: &T, span: Span) -> Option<usize> {
+pub fn indent_of(sess: &impl HasSession, span: Span) -> Option<usize> {
-    snippet_opt(cx, line_span(cx, span)).and_then(|snip| snip.find(|c: char| !c.is_whitespace()))
+    snippet_opt(sess, line_span(sess, span)).and_then(|snip| snip.find(|c: char| !c.is_whitespace()))
 }
 
 /// Gets a snippet of the indentation of the line of a span
-pub fn snippet_indent<T: LintContext>(cx: &T, span: Span) -> Option<String> {
+pub fn snippet_indent(sess: &impl HasSession, span: Span) -> Option<String> {
-    snippet_opt(cx, line_span(cx, span)).map(|mut s| {
+    snippet_opt(sess, line_span(sess, span)).map(|mut s| {
         let len = s.len() - s.trim_start().len();
         s.truncate(len);
         s
@@ -315,8 +340,8 @@ pub fn snippet_indent<T: LintContext>(cx: &T, span: Span) -> Option<String> {
 // sources that the user has no control over.
 // For some reason these attributes don't have any expansion info on them, so
 // we have to check it this way until there is a better way.
-pub fn is_present_in_source<T: LintContext>(cx: &T, span: Span) -> bool {
+pub fn is_present_in_source(sess: &impl HasSession, span: Span) -> bool {
-    if let Some(snippet) = snippet_opt(cx, span) {
+    if let Some(snippet) = snippet_opt(sess, span) {
         if snippet.is_empty() {
             return false;
         }
@@ -407,8 +432,8 @@ fn reindent_multiline_inner(s: &str, ignore_first: bool, indent: Option<usize>,
 /// snippet(cx, span1, "..") // -> "value"
 /// snippet(cx, span2, "..") // -> "Vec::new()"
 /// ```
-pub fn snippet<'a, T: LintContext>(cx: &T, span: Span, default: &'a str) -> Cow<'a, str> {
+pub fn snippet<'a>(sess: &impl HasSession, span: Span, default: &'a str) -> Cow<'a, str> {
-    snippet_opt(cx, span).map_or_else(|| Cow::Borrowed(default), From::from)
+    snippet_opt(sess, span).map_or_else(|| Cow::Borrowed(default), From::from)
 }
 
 /// Same as [`snippet`], but it adapts the applicability level by following rules:
@@ -417,13 +442,13 @@ pub fn snippet<'a, T: LintContext>(cx: &T, span: Span, default: &'a str) -> Cow<
 /// - If the span is inside a macro, change the applicability level to `MaybeIncorrect`.
 /// - If the default value is used and the applicability level is `MachineApplicable`, change it to
 ///   `HasPlaceholders`
-pub fn snippet_with_applicability<'a, T: LintContext>(
+pub fn snippet_with_applicability<'a>(
-    cx: &T,
+    sess: &impl HasSession,
     span: Span,
     default: &'a str,
     applicability: &mut Applicability,
 ) -> Cow<'a, str> {
-    snippet_with_applicability_sess(cx.sess(), span, default, applicability)
+    snippet_with_applicability_sess(sess.sess(), span, default, applicability)
 }
 
 fn snippet_with_applicability_sess<'a>(
@@ -435,7 +460,7 @@ fn snippet_with_applicability_sess<'a>(
     if *applicability != Applicability::Unspecified && span.from_expansion() {
         *applicability = Applicability::MaybeIncorrect;
     }
-    snippet_opt_sess(sess, span).map_or_else(
+    snippet_opt(sess, span).map_or_else(
         || {
             if *applicability == Applicability::MachineApplicable {
                 *applicability = Applicability::HasPlaceholders;
@@ -447,12 +472,8 @@ fn snippet_with_applicability_sess<'a>(
 }
 
 /// Converts a span to a code snippet. Returns `None` if not available.
-pub fn snippet_opt(cx: &impl LintContext, span: Span) -> Option<String> {
+pub fn snippet_opt(sess: &impl HasSession, span: Span) -> Option<String> {
-    snippet_opt_sess(cx.sess(), span)
+    sess.sess().source_map().span_to_snippet(span).ok()
-}
-
-fn snippet_opt_sess(sess: &Session, span: Span) -> Option<String> {
-    sess.source_map().span_to_snippet(span).ok()
 }
 
 /// Converts a span (from a block) to a code snippet if available, otherwise use default.
@@ -489,41 +510,41 @@ fn snippet_opt_sess(sess: &Session, span: Span) -> Option<String> {
 ///     } // aligned with `if`
 /// ```
 /// Note that the first line of the snippet always has 0 indentation.
-pub fn snippet_block<'a, T: LintContext>(
+pub fn snippet_block<'a>(
-    cx: &T,
+    sess: &impl HasSession,
     span: Span,
     default: &'a str,
     indent_relative_to: Option<Span>,
 ) -> Cow<'a, str> {
-    let snip = snippet(cx, span, default);
+    let snip = snippet(sess, span, default);
-    let indent = indent_relative_to.and_then(|s| indent_of(cx, s));
+    let indent = indent_relative_to.and_then(|s| indent_of(sess, s));
     reindent_multiline(snip, true, indent)
 }
 
 /// Same as `snippet_block`, but adapts the applicability level by the rules of
 /// `snippet_with_applicability`.
 pub fn snippet_block_with_applicability<'a>(
-    cx: &impl LintContext,
+    sess: &impl HasSession,
     span: Span,
     default: &'a str,
     indent_relative_to: Option<Span>,
     applicability: &mut Applicability,
 ) -> Cow<'a, str> {
-    let snip = snippet_with_applicability(cx, span, default, applicability);
+    let snip = snippet_with_applicability(sess, span, default, applicability);
-    let indent = indent_relative_to.and_then(|s| indent_of(cx, s));
+    let indent = indent_relative_to.and_then(|s| indent_of(sess, s));
     reindent_multiline(snip, true, indent)
 }
 
 pub fn snippet_block_with_context<'a>(
-    cx: &impl LintContext,
+    sess: &impl HasSession,
     span: Span,
     outer: SyntaxContext,
     default: &'a str,
     indent_relative_to: Option<Span>,
     app: &mut Applicability,
 ) -> (Cow<'a, str>, bool) {
-    let (snip, from_macro) = snippet_with_context(cx, span, outer, default, app);
+    let (snip, from_macro) = snippet_with_context(sess, span, outer, default, app);
-    let indent = indent_relative_to.and_then(|s| indent_of(cx, s));
+    let indent = indent_relative_to.and_then(|s| indent_of(sess, s));
     (reindent_multiline(snip, true, indent), from_macro)
 }
 
@@ -537,13 +558,13 @@ pub fn snippet_block_with_context<'a>(
 ///
 /// This will also return whether or not the snippet is a macro call.
 pub fn snippet_with_context<'a>(
-    cx: &impl LintContext,
+    sess: &impl HasSession,
     span: Span,
     outer: SyntaxContext,
     default: &'a str,
     applicability: &mut Applicability,
 ) -> (Cow<'a, str>, bool) {
-    snippet_with_context_sess(cx.sess(), span, outer, default, applicability)
+    snippet_with_context_sess(sess.sess(), span, outer, default, applicability)
 }
 
 fn snippet_with_context_sess<'a>(
@@ -661,15 +682,15 @@ pub fn trim_span(sm: &SourceMap, span: Span) -> Span {
 /// writeln!(o, "")   ->   writeln!(o, "")
 ///             ^^                   ^^^^
 /// ```
-pub fn expand_past_previous_comma(cx: &LateContext<'_>, span: Span) -> Span {
+pub fn expand_past_previous_comma(sess: &impl HasSession, span: Span) -> Span {
-    let extended = cx.sess().source_map().span_extend_to_prev_char(span, ',', true);
+    let extended = sess.sess().source_map().span_extend_to_prev_char(span, ',', true);
     extended.with_lo(extended.lo() - BytePos(1))
 }
 
 /// Converts `expr` to a `char` literal if it's a `str` literal containing a single
 /// character (or a single byte with `ascii_only`)
 pub fn str_literal_to_char_literal(
-    cx: &LateContext<'_>,
+    sess: &impl HasSession,
     expr: &Expr<'_>,
     applicability: &mut Applicability,
     ascii_only: bool,
@@ -684,7 +705,7 @@ pub fn str_literal_to_char_literal(
         }
         && len == 1
     {
-        let snip = snippet_with_applicability(cx, expr.span, string, applicability);
+        let snip = snippet_with_applicability(sess, expr.span, string, applicability);
         let ch = if let StrStyle::Raw(nhash) = style {
             let nhash = nhash as usize;
             // for raw string: r##"a"##