Merge pull request #2735 from rust-lang-nursery/ice_melting

Check that we don't treat any type but a range type as a range

clippy_lints/src/array_indexing.rs

@@ -73,7 +73,7 @@ fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, e: &'tcx hir::Expr) {
                 }
 
                 // Index is a constant range
-                if let Some(range) = higher::range(index) {
+                if let Some(range) = higher::range(cx, index) {
                     if let Some((start, end)) = to_const_range(cx, range, size) {
                         if start > size || end > size {
                             utils::span_lint(cx, OUT_OF_BOUNDS_INDEXING, e.span, "range is out of bounds");
@@ -83,7 +83,7 @@ fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, e: &'tcx hir::Expr) {
                 }
             }
 
-            if let Some(range) = higher::range(index) {
+            if let Some(range) = higher::range(cx, index) {
                 // Full ranges are always valid
                 if range.start.is_none() && range.end.is_none() {
                     return;

clippy_lints/src/infinite_iter.rs

@@ -167,7 +167,7 @@ fn is_infinite(cx: &LateContext, expr: &Expr) -> Finiteness {
         } else {
             Finite
         },
-        ExprStruct(..) => higher::range(expr)
+        ExprStruct(..) => higher::range(cx, expr)
             .map_or(false, |r| r.end.is_none())
             .into(),
         _ => Finite,

clippy_lints/src/loops.rs

@@ -888,7 +888,7 @@ fn detect_manual_memcpy<'a, 'tcx>(
         start: Some(start),
         ref end,
         limits,
-    }) = higher::range(arg)
+    }) = higher::range(cx, arg)
     {
         // the var must be a single name
         if let PatKind::Binding(_, canonical_id, _, _) = pat.node {
@@ -982,7 +982,7 @@ fn check_for_loop_range<'a, 'tcx>(
         start: Some(start),
         ref end,
         limits,
-    }) = higher::range(arg)
+    }) = higher::range(cx, arg)
     {
         // the var must be a single name
         if let PatKind::Binding(_, canonical_id, ref ident, _) = pat.node {
@@ -1118,7 +1118,7 @@ fn check_for_loop_reverse_range<'a, 'tcx>(cx: &LateContext<'a, 'tcx>, arg: &'tcx
         start: Some(start),
         end: Some(end),
         limits,
-    }) = higher::range(arg)
+    }) = higher::range(cx, arg)
     {
         // ...and both sides are compile-time constant integers...
         if let Some((start_idx, _)) = constant(cx, start) {
@@ -1456,7 +1456,7 @@ fn check_for_mut_range_bound(cx: &LateContext, arg: &Expr, body: &Expr) {
         start: Some(start),
         end: Some(end),
         ..
-    }) = higher::range(arg)
+    }) = higher::range(cx, arg)
     {
         let mut_ids = vec![
             check_for_mutability(cx, start),

clippy_lints/src/ranges.rs

@@ -110,7 +110,7 @@ fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
                     if let ExprMethodCall(ref iter_path, _, ref iter_args ) = *iter;
                     if iter_path.name == "iter";
                     // range expression in .zip() call: 0..x.len()
-                    if let Some(higher::Range { start: Some(start), end: Some(end), .. }) = higher::range(zip_arg);
+                    if let Some(higher::Range { start: Some(start), end: Some(end), .. }) = higher::range(cx, zip_arg);
                     if is_integer_literal(start, 0);
                     // .len() call
                     if let ExprMethodCall(ref len_path, _, ref len_args) = end.node;
@@ -132,7 +132,7 @@ fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
 
         // exclusive range plus one: x..(y+1)
         if_chain! {
-            if let Some(higher::Range { start, end: Some(end), limits: RangeLimits::HalfOpen }) = higher::range(expr);
+            if let Some(higher::Range { start, end: Some(end), limits: RangeLimits::HalfOpen }) = higher::range(cx, expr);
             if let Some(y) = y_plus_one(end);
             then {
                 span_lint_and_then(
@@ -153,7 +153,7 @@ fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
 
         // inclusive range minus one: x..=(y-1)
         if_chain! {
-            if let Some(higher::Range { start, end: Some(end), limits: RangeLimits::Closed }) = higher::range(expr);
+            if let Some(higher::Range { start, end: Some(end), limits: RangeLimits::Closed }) = higher::range(cx, expr);
             if let Some(y) = y_minus_one(end);
             then {
                 span_lint_and_then(

clippy_lints/src/utils/higher.rs

@@ -3,7 +3,7 @@
 
 #![deny(missing_docs_in_private_items)]
 
-use rustc::hir;
+use rustc::{hir, ty};
 use rustc::lint::LateContext;
 use syntax::ast;
 use utils::{is_expn_of, match_def_path, match_qpath, opt_def_id, paths, resolve_node};
@@ -44,7 +44,36 @@ pub struct Range<'a> {
 }
 
 /// Higher a `hir` range to something similar to `ast::ExprKind::Range`.
-pub fn range(expr: &hir::Expr) -> Option<Range> {
+pub fn range<'a, 'b, 'tcx>(cx: &LateContext<'a, 'tcx>, expr: &'b hir::Expr) -> Option<Range<'b>> {
+
+    let def_path = match cx.tables.expr_ty(expr).sty {
+        ty::TyAdt(def, _) => cx.tcx.def_path(def.did),
+        _ => return None,
+    };
+
+    // sanity checks for std::ops::RangeXXXX
+    if def_path.data.len() != 3 {
+        return None;
+    }
+    if def_path.data.get(0)?.data.as_interned_str() != "ops" {
+        return None;
+    }
+    if def_path.data.get(1)?.data.as_interned_str() != "range" {
+        return None;
+    }
+    let type_name = def_path.data.get(2)?.data.as_interned_str();
+    let range_types = [
+        "RangeFrom",
+        "RangeFull",
+        "RangeInclusive",
+        "Range",
+        "RangeTo",
+        "RangeToInclusive",
+    ];
+    if !range_types.contains(&&*type_name.as_str()) {
+        return None;
+    }
+
     /// Find the field named `name` in the field. Always return `Some` for
     /// convenience.
     fn get_field<'a>(name: &str, fields: &'a [hir::Field]) -> Option<&'a hir::Expr> {

tests/run-pass/ice-2727.rs

@@ -0,0 +1,5 @@
+pub fn f(new: fn()) {
+    new();
+}
+
+fn main() {}