diff --git a/src/loops.rs b/src/loops.rs index a381737fe3b..ade4f46b4a0 100644 --- a/src/loops.rs +++ b/src/loops.rs @@ -9,7 +9,7 @@ use rustc::front::map::Node::{NodeBlock}; use std::collections::{HashSet,HashMap}; use utils::{snippet, span_lint, get_parent_expr, match_trait_method, match_type, - in_external_macro, expr_block, span_help_and_lint}; + in_external_macro, expr_block, span_help_and_lint, is_integer_literal}; use utils::{VEC_PATH, LL_PATH}; declare_lint!{ pub NEEDLESS_RANGE_LOOP, Warn, @@ -339,7 +339,7 @@ impl<'v, 't> Visitor<'v> for IncrementVisitor<'v, 't> { match parent.node { ExprAssignOp(op, ref lhs, ref rhs) => if lhs.id == expr.id { - if op.node == BiAdd && is_lit_one(rhs) { + if op.node == BiAdd && is_integer_literal(rhs, 1) { *state = match *state { VarState::Initial if self.depth == 0 => VarState::IncrOnce, _ => VarState::DontWarn @@ -392,7 +392,7 @@ impl<'v, 't> Visitor<'v> for InitializeVisitor<'v, 't> { self.name = Some(ident.node.name); self.state = if let Some(ref init) = local.init { - if is_lit_zero(init) { + if is_integer_literal(init, 0) { VarState::Warn } else { VarState::Declared @@ -425,7 +425,7 @@ impl<'v, 't> Visitor<'v> for InitializeVisitor<'v, 't> { self.state = VarState::DontWarn; }, ExprAssign(ref lhs, ref rhs) if lhs.id == expr.id => { - self.state = if is_lit_zero(rhs) && self.depth == 0 { + self.state = if is_integer_literal(rhs, 0) && self.depth == 0 { VarState::Warn } else { VarState::DontWarn @@ -473,23 +473,3 @@ fn is_conditional(expr: &Expr) -> bool { _ => false } } - -// FIXME: copy/paste from misc.rs -fn is_lit_one(expr: &Expr) -> bool { - if let ExprLit(ref spanned) = expr.node { - if let LitInt(1, _) = spanned.node { - return true; - } - } - false -} - -// FIXME: copy/paste from ranges.rs -fn is_lit_zero(expr: &Expr) -> bool { - if let ExprLit(ref spanned) = expr.node { - if let LitInt(0, _) = spanned.node { - return true; - } - } - false -} diff --git a/src/misc.rs b/src/misc.rs index 2cd6babb9c5..63c2082abde 100644 --- a/src/misc.rs +++ b/src/misc.rs @@ -7,7 +7,7 @@ use syntax::codemap::{Span, Spanned}; use rustc_front::visit::FnKind; use rustc::middle::ty; -use utils::{get_item_name, match_path, snippet, span_lint, walk_ptrs_ty}; +use utils::{get_item_name, match_path, snippet, span_lint, walk_ptrs_ty, is_integer_literal}; use consts::constant; declare_lint!(pub TOPLEVEL_REF_ARG, Warn, @@ -183,7 +183,7 @@ impl LintPass for ModuloOne { fn check_expr(&mut self, cx: &Context, expr: &Expr) { if let ExprBinary(ref cmp, _, ref right) = expr.node { if let &Spanned {node: BinOp_::BiRem, ..} = cmp { - if is_lit_one(right) { + if is_integer_literal(right, 1) { cx.span_lint(MODULO_ONE, expr.span, "any number modulo 1 will be 0"); } } @@ -191,15 +191,6 @@ impl LintPass for ModuloOne { } } -fn is_lit_one(expr: &Expr) -> bool { - if let ExprLit(ref spanned) = expr.node { - if let LitInt(1, _) = spanned.node { - return true; - } - } - false -} - declare_lint!(pub REDUNDANT_PATTERN, Warn, "using `name @ _` in a pattern"); #[derive(Copy,Clone)] diff --git a/src/ranges.rs b/src/ranges.rs index 197afaf1163..97f59a3aadd 100644 --- a/src/ranges.rs +++ b/src/ranges.rs @@ -1,7 +1,7 @@ use rustc::lint::{Context, LintArray, LintPass}; use rustc_front::hir::*; use syntax::codemap::Spanned; -use utils::match_type; +use utils::{match_type, is_integer_literal}; declare_lint! { pub RANGE_STEP_BY_ZERO, Warn, @@ -21,7 +21,7 @@ impl LintPass for StepByZero { ref args) = expr.node { // Only warn on literal ranges. if ident.name == "step_by" && args.len() == 2 && - is_range(cx, &args[0]) && is_lit_zero(&args[1]) { + is_range(cx, &args[0]) && is_integer_literal(&args[1], 0) { cx.span_lint(RANGE_STEP_BY_ZERO, expr.span, "Range::step_by(0) produces an infinite iterator. \ Consider using `std::iter::repeat()` instead") @@ -37,13 +37,3 @@ fn is_range(cx: &Context, expr: &Expr) -> bool { // Note: RangeTo and RangeFull don't have step_by match_type(cx, ty, &["core", "ops", "Range"]) || match_type(cx, ty, &["core", "ops", "RangeFrom"]) } - -fn is_lit_zero(expr: &Expr) -> bool { - // FIXME: use constant folding - if let ExprLit(ref spanned) = expr.node { - if let LitInt(0, _) = spanned.node { - return true; - } - } - false -} diff --git a/src/utils.rs b/src/utils.rs index d6e529048c9..01c9adf866c 100644 --- a/src/utils.rs +++ b/src/utils.rs @@ -244,6 +244,17 @@ pub fn walk_ptrs_ty_depth(ty: ty::Ty) -> (ty::Ty, usize) { inner(ty, 0) } +pub fn is_integer_literal(expr: &Expr, value: u64) -> bool +{ + // FIXME: use constant folding + if let ExprLit(ref spanned) = expr.node { + if let LitInt(v, _) = spanned.node { + return v == value; + } + } + false +} + /// Produce a nested chain of if-lets and ifs from the patterns: /// /// if_let_chain! {