Diagnose unresolved self value in path expression

Author: Veykril

src/tools/rust-analyzer/crates/hir-ty/src/infer/expr.rs

@@ -440,7 +440,8 @@ impl InferenceContext<'_> {
                 let ty = match self.infer_path(p, tgt_expr.into()) {
                     Some(ty) => ty,
                     None => {
-                        if matches!(p, Path::Normal { mod_path, .. } if mod_path.is_ident()) {
+                        if matches!(p, Path::Normal { mod_path, .. } if mod_path.is_ident() || mod_path.is_self())
+                        {
                             self.push_diagnostic(InferenceDiagnostic::UnresolvedIdent {
                                 expr: tgt_expr,
                             });

src/tools/rust-analyzer/crates/ide-diagnostics/src/handlers/unresolved_ident.rs

@@ -53,6 +53,22 @@ fn main() {
     let x = 5;
     let _ = x;
 }
+"#,
+        );
+    }
+
+    #[test]
+    fn unresolved_self_val() {
+        check_diagnostics(
+            r#"
+fn main() {
+    self.a;
+  //^^^^ error: no such value in this scope
+    let self:
+         self =
+            self;
+          //^^^^ error: no such value in this scope
+}
 "#,
         );
     }