Rollup merge of #112475 - chenyukang:yukang-fix-112278, r=compiler-errors

Fix issue for module name when surround the struct literal with parentheses

Fixes #112278

1 files changed, 18 insertions, 7 deletions

diff --git a/compiler/rustc_parse/src/parser/diagnostics.rs b/compiler/rustc_parse/src/parser/diagnostics.rs
index c1454039685..228eff1269f 100644
--- a/compiler/rustc_parse/src/parser/diagnostics.rs
+++ b/compiler/rustc_parse/src/parser/diagnostics.rs
@@ -751,13 +751,24 @@ impl<'a> Parser<'a> {
                     tail.could_be_bare_literal = true;
                     if maybe_struct_name.is_ident() && can_be_struct_literal {
                         // Account for `if Example { a: one(), }.is_pos() {}`.
-                        Err(self.sess.create_err(StructLiteralNeedingParens {
-                            span: maybe_struct_name.span.to(expr.span),
-                            sugg: StructLiteralNeedingParensSugg {
-                                before: maybe_struct_name.span.shrink_to_lo(),
-                                after: expr.span.shrink_to_hi(),
-                            },
-                        }))
+                        // expand `before` so that we take care of module path such as:
+                        // `foo::Bar { ... } `
+                        // we expect to suggest `(foo::Bar { ... })` instead of `foo::(Bar { ... })`
+                        let sm = self.sess.source_map();
+                        let before = maybe_struct_name.span.shrink_to_lo();
+                        if let Ok(extend_before) = sm.span_extend_prev_while(before, |t| {
+                            t.is_alphanumeric() || t == ':' || t == '_'
+                        }) {
+                            Err(self.sess.create_err(StructLiteralNeedingParens {
+                                span: maybe_struct_name.span.to(expr.span),
+                                sugg: StructLiteralNeedingParensSugg {
+                                    before: extend_before.shrink_to_lo(),
+                                    after: expr.span.shrink_to_hi(),
+                                },
+                            }))
+                        } else {
+                            return None;
+                        }
                     } else {
                         self.sess.emit_err(StructLiteralBodyWithoutPath {
                             span: expr.span,