fix(parser): allow escaped type names in import and export specifiers (#26487)

Allow escaped value names such as `import { t\u0079pe as x } from "m"` and the equivalent named exports. Reject escapes only after resolving `type` as a type-only modifier.

Preserve the decoded identifier name in the ambiguous `type as as` form so its AST name remains `type`.

crates/oxc_parser/src/js/module.rs

@@ -873,11 +873,7 @@ impl<'a, C: Config> ParserImpl<'a, C> {
                         can_parse_as_keyword = false;
                     } else {
                         // { type as as }
-                        property_name = Some(ModuleExportName::new_identifier_name(
-                            type_or_name_token.span(),
-                            self.ident(self.token_source(&type_or_name_token)),
-                            self,
-                        ));
+                        property_name = Some(name);
                         name = ModuleExportName::new_identifier_name(
                             second_as.span,
                             second_as.name,
@@ -913,7 +909,7 @@ impl<'a, C: Config> ParserImpl<'a, C> {
             name = self.parse_module_export_name();
         }
 
-        if self.is_ts && type_or_name_token_kind == Kind::Type && type_or_name_token.escaped() {
+        if kind == ImportOrExportKind::Type && type_or_name_token.escaped() {
             self.error(diagnostics::escaped_keyword(type_or_name_token.span()));
         }
 

tasks/coverage/misc/fail/escaped-type-specifier.ts

@@ -0,0 +1,6 @@
+import { t\u0079pe as as x } from "m";
+export { t\u0079pe Foo };
+export { t\u0079pe as };
+export { t\u0079pe as as x };
+export { t\u0079pe Foo } from "m";
+export { t\u0079pe as as x } from "m";

tasks/coverage/misc/pass/escaped-type-specifier-export.ts

@@ -0,0 +1,5 @@
+const type = 0;
+export { t\u0079pe };
+export { t\u0079pe as x };
+export { t\u0079pe as as };
+export type { t\u0079pe as T };

tasks/coverage/misc/pass/escaped-type-specifier-import.ts

@@ -0,0 +1,4 @@
+import { t\u0079pe } from "m";
+import { t\u0079pe as x } from "m";
+import { t\u0079pe as as } from "m";
+import type { t\u0079pe as T } from "m";

tasks/coverage/misc/pass/escaped-type-specifier-reexport.ts

@@ -0,0 +1,4 @@
+export { t\u0079pe } from "m";
+export { t\u0079pe as x } from "m";
+export { t\u0079pe as as } from "m";
+export type { t\u0079pe as T } from "m";

tasks/coverage/snapshots/codegen_misc.snap

@@ -1,3 +1,3 @@
 codegen_misc Summary:
-AST Parsed     : 93/93 (100.00%)
-Positive Passed: 93/93 (100.00%)
+AST Parsed     : 96/96 (100.00%)
+Positive Passed: 96/96 (100.00%)

tasks/coverage/snapshots/formatter_misc.snap

@@ -1,3 +1,3 @@
 formatter_misc Summary:
-AST Parsed     : 93/93 (100.00%)
-Positive Passed: 93/93 (100.00%)
+AST Parsed     : 96/96 (100.00%)
+Positive Passed: 96/96 (100.00%)

tasks/coverage/snapshots/lexer_misc.snap

@@ -1,3 +1,3 @@
 lexer_misc Summary:
-AST Parsed     : 290/290 (100.00%)
-Positive Passed: 290/290 (100.00%)
+AST Parsed     : 294/294 (100.00%)
+Positive Passed: 294/294 (100.00%)

tasks/coverage/snapshots/parser_misc.snap

@@ -1,7 +1,7 @@
 parser_misc Summary:
-AST Parsed     : 93/93 (100.00%)
-Positive Passed: 93/93 (100.00%)
-Negative Passed: 197/197 (100.00%)
+AST Parsed     : 96/96 (100.00%)
+Positive Passed: 96/96 (100.00%)
+Negative Passed: 198/198 (100.00%)
 
   × Cannot assign to 'arguments' in strict mode
    ╭─[misc/fail/arguments-eval-ambient.ts:2:13]
@@ -427,6 +427,52 @@ Negative Passed: 197/197 (100.00%)
    ·                  ─────────
    ╰────
 
+  × Keywords cannot contain escape characters
+   ╭─[misc/fail/escaped-type-specifier.ts:1:10]
+ 1 │ import { t\u0079pe as as x } from "m";
+   ·          ─────────
+ 2 │ export { t\u0079pe Foo };
+   ╰────
+
+  × Keywords cannot contain escape characters
+   ╭─[misc/fail/escaped-type-specifier.ts:2:10]
+ 1 │ import { t\u0079pe as as x } from "m";
+ 2 │ export { t\u0079pe Foo };
+   ·          ─────────
+ 3 │ export { t\u0079pe as };
+   ╰────
+
+  × Keywords cannot contain escape characters
+   ╭─[misc/fail/escaped-type-specifier.ts:3:10]
+ 2 │ export { t\u0079pe Foo };
+ 3 │ export { t\u0079pe as };
+   ·          ─────────
+ 4 │ export { t\u0079pe as as x };
+   ╰────
+
+  × Keywords cannot contain escape characters
+   ╭─[misc/fail/escaped-type-specifier.ts:4:10]
+ 3 │ export { t\u0079pe as };
+ 4 │ export { t\u0079pe as as x };
+   ·          ─────────
+ 5 │ export { t\u0079pe Foo } from "m";
+   ╰────
+
+  × Keywords cannot contain escape characters
+   ╭─[misc/fail/escaped-type-specifier.ts:5:10]
+ 4 │ export { t\u0079pe as as x };
+ 5 │ export { t\u0079pe Foo } from "m";
+   ·          ─────────
+ 6 │ export { t\u0079pe as as x } from "m";
+   ╰────
+
+  × Keywords cannot contain escape characters
+   ╭─[misc/fail/escaped-type-specifier.ts:6:10]
+ 5 │ export { t\u0079pe Foo } from "m";
+ 6 │ export { t\u0079pe as as x } from "m";
+   ·          ─────────
+   ╰────
+
   × A unary expression with the '-' operator cannot be used as the left operand of an exponentiation expression
    ╭─[misc/fail/exponentiation-left-operands.ts:1:1]
  1 │ -value ** 2;

tasks/coverage/snapshots/semantic_misc.snap

@@ -1,6 +1,6 @@
 semantic_misc Summary:
-AST Parsed     : 93/93 (100.00%)
-Positive Passed: 89/93 (95.70%)
+AST Parsed     : 96/96 (100.00%)
+Positive Passed: 92/96 (95.83%)
 semantic Error: tasks/coverage/misc/pass/declare-let-private.ts
 Bindings mismatch:
 after transform: ScopeId(0): ["private"]

tasks/coverage/snapshots/transformer_misc.snap

@@ -1,3 +1,3 @@
 transformer_misc Summary:
-AST Parsed     : 93/93 (100.00%)
-Positive Passed: 93/93 (100.00%)
+AST Parsed     : 96/96 (100.00%)
+Positive Passed: 96/96 (100.00%)