Attempt to check method call sites for ambiguity

Author: sjwang05

clippy_lints/src/ambiguous_method_calls.rs

@@ -88,6 +88,7 @@ impl<'tcx> LateLintPass<'tcx> for AmbiguousMethodCalls {
 
         // Check methods in trait impls and struct impls
         if let FnKind::Method(ident, _) = kind {
+            // FIXME: also keep track of the Ty of the struct for call site checking
             insert_method(is_trait_impl, ident);
 
             if has_ambiguous_name(ident) {
@@ -110,8 +111,24 @@ impl<'tcx> LateLintPass<'tcx> for AmbiguousMethodCalls {
                 );
             }
         }
+    }
 
-        // TODO: check method call sites as well
+    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx rustc_hir::Expr<'_>) {
+        if let rustc_hir::ExprKind::MethodCall(path, _receiver, _, call_span) = &expr.kind
+        {
+            let struct_methods = struct_methods().lock().unwrap();
+            if struct_methods.contains_key(&path.ident.name) {
+                // FIXME: only report after checking receiver's Ty
+                span_lint_and_help(
+                    cx,
+                    AMBIGUOUS_METHOD_CALLS,
+                    *call_span,
+                    "ambiguous struct method call",
+                    None,
+                    "consider renaming the struct impl's method or explicitly qualifying the call site",
+                );
+            }
+        }
     }
 }
 

tests/ui/ambiguous_method_calls.rs

@@ -1,3 +1,4 @@
+#![allow(dead_code)]
 #![warn(clippy::ambiguous_method_calls)]
 
 trait MyTrait {

tests/ui/ambiguous_method_calls.stderr

@@ -1,22 +1,27 @@
-error: ambiguous method call
-  --> $DIR/ambiguous_method_calls.rs:21:5
+error: ambiguous trait method name
+  --> $DIR/ambiguous_method_calls.rs:22:8
    |
-LL | /     fn ambiguous(&self) {
-LL | |         println!("trait impl");
-LL | |     }
-   | |_____^
+LL |     fn ambiguous(&self) {
+   |        ^^^^^^^^^
    |
-   = help: consider renaming the struct impl's method
    = note: `-D clippy::ambiguous-method-calls` implied by `-D warnings`
    = help: to override `-D warnings` add `#[allow(clippy::ambiguous_method_calls)]`
 
-error: ambiguous method call
-  --> $DIR/ambiguous_method_calls.rs:11:8
+error: ambiguous struct method name
+  --> $DIR/ambiguous_method_calls.rs:12:8
    |
 LL |     fn ambiguous(&self) {
    |        ^^^^^^^^^
    |
    = help: consider renaming the struct impl's method
 
-error: aborting due to 2 previous errors
+error: ambiguous struct method call
+  --> $DIR/ambiguous_method_calls.rs:34:10
+   |
+LL |     data.ambiguous();
+   |          ^^^^^^^^^^^
+   |
+   = help: consider renaming the struct impl's method or explicitly qualifying the call site
+
+error: aborting due to 3 previous errors