Fix bug with parsing TS generic async arrow function (#9055)

babel · Nov 21, 2018 · 4f16a12 · 4f16a12
1 parent e7f0c06
commit 4f16a12
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Showing 3 changed files with 140 additions and 0 deletions.
diff --git a/packages/babel-parser/src/plugins/typescript.js b/packages/babel-parser/src/plugins/typescript.js
@@ -1299,11 +1299,17 @@ export default (superClass: Class<Parser>): Class<Parser> =>
         return undefined;
       }
 
+      const oldInAsync = this.state.inAsync;
+      const oldInGenerator = this.state.inGenerator;
+      this.state.inAsync = true;
+      this.state.inGenerator = false;
       res.id = null;
       res.generator = false;
       res.expression = true; // May be set again by parseFunctionBody.
       res.async = true;
       this.parseFunctionBody(res, true);
+      this.state.inAsync = oldInAsync;
+      this.state.inGenerator = oldInGenerator;
       return this.finishNode(res, "ArrowFunctionExpression");
     }
 

diff --git a/packages/babel-parser/test/fixtures/typescript/arrow-function/async-await-null/input.js b/packages/babel-parser/test/fixtures/typescript/arrow-function/async-await-null/input.js
@@ -0,0 +1 @@
+async <T>() => await null;
diff --git a/packages/babel-parser/test/fixtures/typescript/arrow-function/async-await-null/output.json b/packages/babel-parser/test/fixtures/typescript/arrow-function/async-await-null/output.json
@@ -0,0 +1,133 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 26,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 1,
+      "column": 26
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 26,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 1,
+        "column": 26
+      }
+    },
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "ExpressionStatement",
+        "start": 0,
+        "end": 26,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 26
+          }
+        },
+        "expression": {
+          "type": "ArrowFunctionExpression",
+          "start": 0,
+          "end": 25,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 0
+            },
+            "end": {
+              "line": 1,
+              "column": 25
+            }
+          },
+          "typeParameters": {
+            "type": "TSTypeParameterDeclaration",
+            "start": 6,
+            "end": 9,
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 6
+              },
+              "end": {
+                "line": 1,
+                "column": 9
+              }
+            },
+            "params": [
+              {
+                "type": "TSTypeParameter",
+                "start": 7,
+                "end": 8,
+                "loc": {
+                  "start": {
+                    "line": 1,
+                    "column": 7
+                  },
+                  "end": {
+                    "line": 1,
+                    "column": 8
+                  }
+                },
+                "name": "T"
+              }
+            ]
+          },
+          "params": [],
+          "id": null,
+          "generator": false,
+          "expression": true,
+          "async": true,
+          "body": {
+            "type": "AwaitExpression",
+            "start": 15,
+            "end": 25,
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 15
+              },
+              "end": {
+                "line": 1,
+                "column": 25
+              }
+            },
+            "argument": {
+              "type": "NullLiteral",
+              "start": 21,
+              "end": 25,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 21
+                },
+                "end": {
+                  "line": 1,
+                  "column": 25
+                }
+              }
+            }
+          }
+        }
+      }
+    ],
+    "directives": []
+  }
+}