fix: allow liberal named type-as imports (#14522)

packages/babel-parser/src/plugins/typescript/index.js

@@ -3696,9 +3696,19 @@ export default (superClass: Class<Parser>): Class<Parser> =>
       } else if (tokenIsKeywordOrIdentifier(this.state.type)) {
         // { type something ...? }
         hasTypeSpecifier = true;
-        leftOfAs = isImport
-          ? this.parseIdentifier()
-          : this.parseModuleExportName();
+        if (isImport) {
+          leftOfAs = this.parseIdentifier(true);
+          if (!this.isContextual(tt._as)) {
+            this.checkReservedWord(
+              leftOfAs.name,
+              leftOfAs.loc.start,
+              true,
+              true,
+            );
+          }
+        } else {
+          leftOfAs = this.parseModuleExportName();
+        }
       }
       if (hasTypeSpecifier && isInTypeOnlyImportExport) {
         this.raise(

packages/babel-parser/test/fixtures/typescript/type-only-import-export-specifiers/export-type-only-keyword-from/input.ts

@@ -0,0 +1 @@
+export { type if } from "./mode.js"

packages/babel-parser/test/fixtures/typescript/type-only-import-export-specifiers/export-type-only-keyword-from/output.json

@@ -0,0 +1,45 @@
+{
+  "type": "File",
+  "start":0,"end":35,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":35,"index":35}},
+  "program": {
+    "type": "Program",
+    "start":0,"end":35,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":35,"index":35}},
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "ExportNamedDeclaration",
+        "start":0,"end":35,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":35,"index":35}},
+        "exportKind": "value",
+        "specifiers": [
+          {
+            "type": "ExportSpecifier",
+            "start":9,"end":16,"loc":{"start":{"line":1,"column":9,"index":9},"end":{"line":1,"column":16,"index":16}},
+            "local": {
+              "type": "Identifier",
+              "start":14,"end":16,"loc":{"start":{"line":1,"column":14,"index":14},"end":{"line":1,"column":16,"index":16},"identifierName":"if"},
+              "name": "if"
+            },
+            "exported": {
+              "type": "Identifier",
+              "start":14,"end":16,"loc":{"start":{"line":1,"column":14,"index":14},"end":{"line":1,"column":16,"index":16},"identifierName":"if"},
+              "name": "if"
+            },
+            "exportKind": "type"
+          }
+        ],
+        "source": {
+          "type": "StringLiteral",
+          "start":24,"end":35,"loc":{"start":{"line":1,"column":24,"index":24},"end":{"line":1,"column":35,"index":35}},
+          "extra": {
+            "rawValue": "./mode.js",
+            "raw": "\"./mode.js\""
+          },
+          "value": "./mode.js"
+        },
+        "declaration": null
+      }
+    ],
+    "directives": []
+  }
+}

packages/babel-parser/test/fixtures/typescript/type-only-import-export-specifiers/import-invalid-type-named-keywords/input.ts

@@ -0,0 +1 @@
+import { type if } from "./mod.js";

packages/babel-parser/test/fixtures/typescript/type-only-import-export-specifiers/import-invalid-type-named-keywords/output.json

@@ -0,0 +1,47 @@
+{
+  "type": "File",
+  "start":0,"end":35,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":35,"index":35}},
+  "errors": [
+    "SyntaxError: Unexpected keyword 'if'. (1:14)"
+  ],
+  "program": {
+    "type": "Program",
+    "start":0,"end":35,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":35,"index":35}},
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "ImportDeclaration",
+        "start":0,"end":35,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":35,"index":35}},
+        "importKind": "value",
+        "specifiers": [
+          {
+            "type": "ImportSpecifier",
+            "start":9,"end":16,"loc":{"start":{"line":1,"column":9,"index":9},"end":{"line":1,"column":16,"index":16}},
+            "imported": {
+              "type": "Identifier",
+              "start":14,"end":16,"loc":{"start":{"line":1,"column":14,"index":14},"end":{"line":1,"column":16,"index":16},"identifierName":"if"},
+              "name": "if"
+            },
+            "local": {
+              "type": "Identifier",
+              "start":14,"end":16,"loc":{"start":{"line":1,"column":14,"index":14},"end":{"line":1,"column":16,"index":16},"identifierName":"if"},
+              "name": "if"
+            },
+            "importKind": "type"
+          }
+        ],
+        "source": {
+          "type": "StringLiteral",
+          "start":24,"end":34,"loc":{"start":{"line":1,"column":24,"index":24},"end":{"line":1,"column":34,"index":34}},
+          "extra": {
+            "rawValue": "./mod.js",
+            "raw": "\"./mod.js\""
+          },
+          "value": "./mod.js"
+        }
+      }
+    ],
+    "directives": []
+  }
+}

packages/babel-parser/test/fixtures/typescript/type-only-import-export-specifiers/import-type-only-named-keywords-as/input.ts

@@ -0,0 +1 @@
+import { type default as a, type if as b } from "./mod.js";

packages/babel-parser/test/fixtures/typescript/type-only-import-export-specifiers/import-type-only-named-keywords-as/output.json

@@ -0,0 +1,59 @@
+{
+  "type": "File",
+  "start":0,"end":59,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":59,"index":59}},
+  "program": {
+    "type": "Program",
+    "start":0,"end":59,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":59,"index":59}},
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "ImportDeclaration",
+        "start":0,"end":59,"loc":{"start":{"line":1,"column":0,"index":0},"end":{"line":1,"column":59,"index":59}},
+        "importKind": "value",
+        "specifiers": [
+          {
+            "type": "ImportSpecifier",
+            "start":9,"end":26,"loc":{"start":{"line":1,"column":9,"index":9},"end":{"line":1,"column":26,"index":26}},
+            "imported": {
+              "type": "Identifier",
+              "start":14,"end":21,"loc":{"start":{"line":1,"column":14,"index":14},"end":{"line":1,"column":21,"index":21},"identifierName":"default"},
+              "name": "default"
+            },
+            "local": {
+              "type": "Identifier",
+              "start":25,"end":26,"loc":{"start":{"line":1,"column":25,"index":25},"end":{"line":1,"column":26,"index":26},"identifierName":"a"},
+              "name": "a"
+            },
+            "importKind": "type"
+          },
+          {
+            "type": "ImportSpecifier",
+            "start":28,"end":40,"loc":{"start":{"line":1,"column":28,"index":28},"end":{"line":1,"column":40,"index":40}},
+            "imported": {
+              "type": "Identifier",
+              "start":33,"end":35,"loc":{"start":{"line":1,"column":33,"index":33},"end":{"line":1,"column":35,"index":35},"identifierName":"if"},
+              "name": "if"
+            },
+            "local": {
+              "type": "Identifier",
+              "start":39,"end":40,"loc":{"start":{"line":1,"column":39,"index":39},"end":{"line":1,"column":40,"index":40},"identifierName":"b"},
+              "name": "b"
+            },
+            "importKind": "type"
+          }
+        ],
+        "source": {
+          "type": "StringLiteral",
+          "start":48,"end":58,"loc":{"start":{"line":1,"column":48,"index":48},"end":{"line":1,"column":58,"index":58}},
+          "extra": {
+            "rawValue": "./mod.js",
+            "raw": "\"./mod.js\""
+          },
+          "value": "./mod.js"
+        }
+      }
+    ],
+    "directives": []
+  }
+}