Auto merge of #4551 - mikerite:fix-ice-reporting, r=llogiq

[rust.git] / clippy_lints / src / utils / mod.rs

diff --git a/clippy_lints/src/utils/mod.rs b/clippy_lints/src/utils/mod.rs
index 8fb45899653c0d3d1a740d5f5ff871be42af7a1d..9165f8d74d7831bc1f2e453a2b58100db5d1260f 100644 (file)
--- a/clippy_lints/src/utils/mod.rs
+++ b/clippy_lints/src/utils/mod.rs
@@ -47,6 +47,7 @@
 use syntax::source_map::{Span, DUMMY_SP};
 use syntax::symbol::{kw, Symbol};
 
+use crate::consts::{constant, Constant};
 use crate::reexport::*;
 
 /// Returns `true` if the two spans come from differing expansions (i.e., one is
@@ -88,6 +89,10 @@ pub fn in_constant(cx: &LateContext<'_, '_>, id: HirId) -> bool {
             node: ItemKind::Fn(_, header, ..),
             ..
         }) => header.constness == Constness::Const,
+        Node::ImplItem(&ImplItem {
+            node: ImplItemKind::Method(ref sig, _),
+            ..
+        }) => sig.header.constness == Constness::Const,
         _ => false,
     }
 }
@@ -126,6 +131,14 @@ pub fn match_type(cx: &LateContext<'_, '_>, ty: Ty<'_>, path: &[&str]) -> bool {
     }
 }
 
+/// Checks if the type is equal to a diagnostic item
+pub fn is_type_diagnostic_item(cx: &LateContext<'_, '_>, ty: Ty<'_>, diag_item: Symbol) -> bool {
+    match ty.sty {
+        ty::Adt(adt, _) => cx.tcx.is_diagnostic_item(diag_item, adt.did),
+        _ => false,
+    }
+}
+
 /// Checks if the method call given in `expr` belongs to the given trait.
 pub fn match_trait_method(cx: &LateContext<'_, '_>, expr: &Expr, path: &[&str]) -> bool {
     let def_id = cx.tables.type_dependent_def_id(expr.hir_id).unwrap();
@@ -260,6 +273,19 @@ pub fn path_to_res(cx: &LateContext<'_, '_>, path: &[&str]) -> Option<(def::Res)
     }
 }
 
+pub fn qpath_res(cx: &LateContext<'_, '_>, qpath: &hir::QPath, id: hir::HirId) -> Res {
+    match qpath {
+        hir::QPath::Resolved(_, path) => path.res,
+        hir::QPath::TypeRelative(..) => {
+            if cx.tcx.has_typeck_tables(id.owner_def_id()) {
+                cx.tcx.typeck_tables_of(id.owner_def_id()).qpath_res(qpath, id)
+            } else {
+                Res::Err
+            }
+        },
+    }
+}
+
 /// Convenience function to get the `DefId` of a trait by path.
 /// It could be a trait or trait alias.
 pub fn get_trait_def_id(cx: &LateContext<'_, '_>, path: &[&str]) -> Option<DefId> {
@@ -338,26 +364,28 @@ pub fn resolve_node(cx: &LateContext<'_, '_>, qpath: &QPath, id: HirId) -> Res {
 }
 
 /// Returns the method names and argument list of nested method call expressions that make up
-/// `expr`.
-pub fn method_calls(expr: &Expr, max_depth: usize) -> (Vec<Symbol>, Vec<&[Expr]>) {
+/// `expr`. method/span lists are sorted with the most recent call first.
+pub fn method_calls(expr: &Expr, max_depth: usize) -> (Vec<Symbol>, Vec<&[Expr]>, Vec<Span>) {
     let mut method_names = Vec::with_capacity(max_depth);
     let mut arg_lists = Vec::with_capacity(max_depth);
+    let mut spans = Vec::with_capacity(max_depth);
 
     let mut current = expr;
     for _ in 0..max_depth {
-        if let ExprKind::MethodCall(path, _, args) = &current.node {
+        if let ExprKind::MethodCall(path, span, args) = &current.node {
             if args.iter().any(|e| e.span.from_expansion()) {
                 break;
             }
             method_names.push(path.ident.name);
             arg_lists.push(&**args);
+            spans.push(*span);
             current = &args[0];
         } else {
             break;
         }
     }
 
-    (method_names, arg_lists)
+    (method_names, arg_lists, spans)
 }
 
 /// Matches an `Expr` against a chain of methods, and return the matched `Expr`s.
@@ -392,10 +420,9 @@ pub fn method_chain_args<'a>(expr: &'a Expr, methods: &[&str]) -> Option<Vec<&'a
 
 /// Returns `true` if the provided `def_id` is an entrypoint to a program.
 pub fn is_entrypoint_fn(cx: &LateContext<'_, '_>, def_id: DefId) -> bool {
-    if let Some((entry_fn_def_id, _)) = cx.tcx.entry_fn(LOCAL_CRATE) {
-        return def_id == entry_fn_def_id;
-    }
-    false
+    cx.tcx
+        .entry_fn(LOCAL_CRATE)
+        .map_or(false, |(entry_fn_def_id, _)| def_id == entry_fn_def_id)
 }
 
 /// Gets the name of the item the expression is in, if available.
@@ -656,6 +683,24 @@ fn inner(ty: Ty<'_>, depth: usize) -> (Ty<'_>, usize) {
     inner(ty, 0)
 }
 
+/// Checks whether the given expression is a constant integer of the given value.
+/// unlike `is_integer_literal`, this version does const folding
+pub fn is_integer_const(cx: &LateContext<'_, '_>, e: &Expr, value: u128) -> bool {
+    if is_integer_literal(e, value) {
+        return true;
+    }
+    let map = cx.tcx.hir();
+    let parent_item = map.get_parent_item(e.hir_id);
+    if let Some((Constant::Int(v), _)) = map
+        .maybe_body_owned_by(parent_item)
+        .and_then(|body_id| constant(cx, cx.tcx.body_tables(body_id), e))
+    {
+        value == v
+    } else {
+        false
+    }
+}
+
 /// Checks whether the given expression is a constant literal of the given value.
 pub fn is_integer_literal(expr: &Expr, value: u128) -> bool {
     // FIXME: use constant folding
@@ -1120,7 +1165,6 @@ fn test_without_block_comments_lines_without_block_comments() {
 }
 
 pub fn match_def_path<'a, 'tcx>(cx: &LateContext<'a, 'tcx>, did: DefId, syms: &[&str]) -> bool {
-    // HACK: find a way to use symbols from clippy or just go fully to diagnostic items
-    let syms: Vec<_> = syms.iter().map(|sym| Symbol::intern(sym)).collect();
-    cx.match_def_path(did, &syms)
+    let path = cx.get_def_path(did);
+    path.len() == syms.len() && path.into_iter().zip(syms.iter()).all(|(a, &b)| a.as_str() == b)
 }