[ts] Disallow invalid type annotations in ExpressionStatements (#12185)

* Fix regression with invalid type annotations in ExpressionStatements

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

@@ -1816,25 +1816,27 @@ export default (superClass: Class<Parser>): Class<Parser> =>
       }
     }
 
-    parseExprListItem(
+    tsCheckForInvalidTypeCasts(items: $ReadOnlyArray<?N.Expression>) {
-      allowEmpty: ?boolean,
+      items.forEach(node => {
-      refExpressionErrors?: ?ExpressionErrors,
+        if (node?.type === "TSTypeCastExpression") {
-      refNeedsArrowPos: ?Pos,
+          this.raise(
-      allowPlaceholder: ?boolean,
+            node.typeAnnotation.start,
-    ): ?N.Expression {
+            TSErrors.UnexpectedTypeAnnotation,
-      const node = super.parseExprListItem(
+          );
-        allowEmpty,
+        }
-        refExpressionErrors,
+      });
-        refNeedsArrowPos,
+    }
-        allowPlaceholder,
-      );
 
-      // Handle `func(a: T)` or `func<T>(a: T)`
+    toReferencedList(
-      if (!refNeedsArrowPos && node?.type === "TSTypeCastExpression") {
+      exprList: $ReadOnlyArray<?N.Expression>,
-        this.raise(node.start, TSErrors.UnexpectedTypeAnnotation);
+      isInParens?: boolean, // eslint-disable-line no-unused-vars
-      }
+    ): $ReadOnlyArray<?N.Expression> {
-
+      // Handles invalid scenarios like: `f(a:b)`, `(a:b);`, and `(a:b,c:d)`.
-      return node;
+      //
+      // Note that `f<T>(a:b)` goes through a different path and is handled
+      // in `parseSubscript` directly.
+      this.tsCheckForInvalidTypeCasts(exprList);
+      return exprList;
     }
 
     parseSubscript(
@@ -1886,6 +1888,10 @@ export default (superClass: Class<Parser>): Class<Parser> =>
                 tt.parenR,
                 /* possibleAsync */ false,
               );
+
+              // Handles invalid case: `f<T>(a:b)`
+              this.tsCheckForInvalidTypeCasts(node.arguments);
+
               node.typeParameters = typeArguments;
               return this.finishCallExpression(node, state.optionalChainMember);
             } else if (this.match(tt.backQuote)) {

packages/babel-parser/test/fixtures/typescript/cast/invalid/input.ts

@@ -0,0 +1,2 @@
+(a:b);
+(a:b,c:d);

packages/babel-parser/test/fixtures/typescript/cast/invalid/output.json

@@ -0,0 +1,106 @@
+{
+  "type": "File",
+  "start":0,"end":17,"loc":{"start":{"line":1,"column":0},"end":{"line":2,"column":10}},
+  "errors": [
+    "SyntaxError: Did not expect a type annotation here. (1:2)",
+    "SyntaxError: Did not expect a type annotation here. (2:2)",
+    "SyntaxError: Did not expect a type annotation here. (2:6)"
+  ],
+  "program": {
+    "type": "Program",
+    "start":0,"end":17,"loc":{"start":{"line":1,"column":0},"end":{"line":2,"column":10}},
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "ExpressionStatement",
+        "start":0,"end":6,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":6}},
+        "expression": {
+          "type": "TSTypeCastExpression",
+          "start":1,"end":4,"loc":{"start":{"line":1,"column":1},"end":{"line":1,"column":4}},
+          "extra": {
+            "parenthesized": true,
+            "parenStart": 0
+          },
+          "expression": {
+            "type": "Identifier",
+            "start":1,"end":2,"loc":{"start":{"line":1,"column":1},"end":{"line":1,"column":2},"identifierName":"a"},
+            "name": "a"
+          },
+          "typeAnnotation": {
+            "type": "TSTypeAnnotation",
+            "start":2,"end":4,"loc":{"start":{"line":1,"column":2},"end":{"line":1,"column":4}},
+            "typeAnnotation": {
+              "type": "TSTypeReference",
+              "start":3,"end":4,"loc":{"start":{"line":1,"column":3},"end":{"line":1,"column":4}},
+              "typeName": {
+                "type": "Identifier",
+                "start":3,"end":4,"loc":{"start":{"line":1,"column":3},"end":{"line":1,"column":4},"identifierName":"b"},
+                "name": "b"
+              }
+            }
+          }
+        }
+      },
+      {
+        "type": "ExpressionStatement",
+        "start":7,"end":17,"loc":{"start":{"line":2,"column":0},"end":{"line":2,"column":10}},
+        "expression": {
+          "type": "SequenceExpression",
+          "start":8,"end":15,"loc":{"start":{"line":2,"column":1},"end":{"line":2,"column":8}},
+          "extra": {
+            "parenthesized": true,
+            "parenStart": 7
+          },
+          "expressions": [
+            {
+              "type": "TSTypeCastExpression",
+              "start":8,"end":11,"loc":{"start":{"line":2,"column":1},"end":{"line":2,"column":4}},
+              "expression": {
+                "type": "Identifier",
+                "start":8,"end":9,"loc":{"start":{"line":2,"column":1},"end":{"line":2,"column":2},"identifierName":"a"},
+                "name": "a"
+              },
+              "typeAnnotation": {
+                "type": "TSTypeAnnotation",
+                "start":9,"end":11,"loc":{"start":{"line":2,"column":2},"end":{"line":2,"column":4}},
+                "typeAnnotation": {
+                  "type": "TSTypeReference",
+                  "start":10,"end":11,"loc":{"start":{"line":2,"column":3},"end":{"line":2,"column":4}},
+                  "typeName": {
+                    "type": "Identifier",
+                    "start":10,"end":11,"loc":{"start":{"line":2,"column":3},"end":{"line":2,"column":4},"identifierName":"b"},
+                    "name": "b"
+                  }
+                }
+              }
+            },
+            {
+              "type": "TSTypeCastExpression",
+              "start":12,"end":15,"loc":{"start":{"line":2,"column":5},"end":{"line":2,"column":8}},
+              "expression": {
+                "type": "Identifier",
+                "start":12,"end":13,"loc":{"start":{"line":2,"column":5},"end":{"line":2,"column":6},"identifierName":"c"},
+                "name": "c"
+              },
+              "typeAnnotation": {
+                "type": "TSTypeAnnotation",
+                "start":13,"end":15,"loc":{"start":{"line":2,"column":6},"end":{"line":2,"column":8}},
+                "typeAnnotation": {
+                  "type": "TSTypeReference",
+                  "start":14,"end":15,"loc":{"start":{"line":2,"column":7},"end":{"line":2,"column":8}},
+                  "typeName": {
+                    "type": "Identifier",
+                    "start":14,"end":15,"loc":{"start":{"line":2,"column":7},"end":{"line":2,"column":8},"identifierName":"d"},
+                    "name": "d"
+                  }
+                }
+              }
+            }
+          ]
+        }
+      }
+    ],
+    "directives": []
+  }
+}

packages/babel-parser/test/fixtures/typescript/cast/parameter-typecast/output.json

@@ -2,8 +2,8 @@
   "type": "File",
   "start":0,"end":26,"loc":{"start":{"line":1,"column":0},"end":{"line":2,"column":14}},
   "errors": [
-    "SyntaxError: Did not expect a type annotation here. (1:5)",
+    "SyntaxError: Did not expect a type annotation here. (1:6)",
-    "SyntaxError: Did not expect a type annotation here. (2:8)"
+    "SyntaxError: Did not expect a type annotation here. (2:9)"
   ],
   "program": {
     "type": "Program",