Refactor parseSubscript (#10937)

* refactor: unify optionalMemberExpression generation

* test: add optional calls invalid typecasts

* fix: do not parse async arrow when call is optional

* test: update test fixtures

packages/babel-parser/src/parser/expression.js

@@ -582,63 +582,46 @@ export default class ExpressionParser extends LValParser {
         startLoc,
         noCalls,
       );
-    } else if (this.match(tt.questionDot)) {
+    }
+    let optional = false;
+    if (this.match(tt.questionDot)) {
       this.expectPlugin("optionalChaining");
-      state.optionalChainMember = true;
+      state.optionalChainMember = optional = true;
       if (noCalls && this.lookaheadCharCode() === charCodes.leftParenthesis) {
         state.stop = true;
         return base;
       }
       this.next();
-
-      const node = this.startNodeAt(startPos, startLoc);
-
-      if (this.eat(tt.bracketL)) {
-        node.object = base;
-        node.property = this.parseExpression();
-        node.computed = true;
-        node.optional = true;
-        this.expect(tt.bracketR);
-        return this.finishNode(node, "OptionalMemberExpression");
-      } else if (this.eat(tt.parenL)) {
-        node.callee = base;
-        node.arguments = this.parseCallExpressionArguments(tt.parenR, false);
-        node.optional = true;
-        return this.finishCallExpression(node, /* optional */ true);
-      } else {
-        node.object = base;
-        node.property = this.parseIdentifier(true);
-        node.computed = false;
-        node.optional = true;
-        return this.finishNode(node, "OptionalMemberExpression");
-      }
-    } else if (this.eat(tt.dot)) {
+    }
+    const computed = this.eat(tt.bracketL);
+    if (
+      (optional && !this.match(tt.parenL) && !this.match(tt.backQuote)) ||
+      computed ||
+      this.eat(tt.dot)
+    ) {
       const node = this.startNodeAt(startPos, startLoc);
       node.object = base;
-      node.property = this.parseMaybePrivateName();
-      node.computed = false;
+      node.property = computed
+        ? this.parseExpression()
+        : optional
+        ? this.parseIdentifier(true)
+        : this.parseMaybePrivateName();
+      node.computed = computed;
       if (
         node.property.type === "PrivateName" &&
         node.object.type === "Super"
       ) {
         this.raise(startPos, "Private fields can't be accessed on super");
       }
-      if (state.optionalChainMember) {
-        node.optional = false;
-        return this.finishNode(node, "OptionalMemberExpression");
+      if (computed) {
+        this.expect(tt.bracketR);
       }
-      return this.finishNode(node, "MemberExpression");
-    } else if (this.eat(tt.bracketL)) {
-      const node = this.startNodeAt(startPos, startLoc);
-      node.object = base;
-      node.property = this.parseExpression();
-      node.computed = true;
-      this.expect(tt.bracketR);
       if (state.optionalChainMember) {
-        node.optional = false;
+        node.optional = optional;
         return this.finishNode(node, "OptionalMemberExpression");
+      } else {
+        return this.finishNode(node, "MemberExpression");
       }
-      return this.finishNode(node, "MemberExpression");
     } else if (!noCalls && this.match(tt.parenL)) {
       const oldMaybeInArrowParameters = this.state.maybeInArrowParameters;
       const oldYieldPos = this.state.yieldPos;
@@ -652,16 +635,21 @@ export default class ExpressionParser extends LValParser {
       let node = this.startNodeAt(startPos, startLoc);
       node.callee = base;
 
-      node.arguments = this.parseCallExpressionArguments(
-        tt.parenR,
-        state.maybeAsyncArrow,
-        base.type === "Import",
-        base.type !== "Super",
-        node,
-      );
+      if (optional) {
+        node.optional = true;
+        node.arguments = this.parseCallExpressionArguments(tt.parenR, false);
+      } else {
+        node.arguments = this.parseCallExpressionArguments(
+          tt.parenR,
+          state.maybeAsyncArrow,
+          base.type === "Import",
+          base.type !== "Super",
+          node,
+        );
+      }
       this.finishCallExpression(node, state.optionalChainMember);
 
-      if (state.maybeAsyncArrow && this.shouldParseAsyncArrow()) {
+      if (state.maybeAsyncArrow && this.shouldParseAsyncArrow() && !optional) {
         state.stop = true;
 
         node = this.parseAsyncArrowFromCallExpression(

packages/babel-parser/test/fixtures/flow/typecasts/fail-in-async-optional-calls/input.js

@@ -0,0 +1 @@
+async?.(bar: string) => {}

packages/babel-parser/test/fixtures/flow/typecasts/fail-in-async-optional-calls/options.json

@@ -0,0 +1,8 @@
+{
+  "sourceType": "module",
+  "plugins": [
+    "flow",
+    "optionalChaining"
+  ],
+  "throws": "Unexpected token, expected \";\" (1:21)"
+}

packages/babel-parser/test/fixtures/flow/typecasts/fail-in-optional-calls/input.js

@@ -0,0 +1 @@
+funccall?.(a, b: string);

packages/babel-parser/test/fixtures/flow/typecasts/fail-in-optional-calls/options.json

@@ -0,0 +1,7 @@
+{
+  "sourceType": "module",
+  "plugins": [
+    "flow",
+    "optionalChaining"
+  ]
+}

packages/babel-parser/test/fixtures/flow/typecasts/fail-in-optional-calls/output.json

@@ -0,0 +1,167 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 25,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 1,
+      "column": 25
+    }
+  },
+  "errors": [
+    "SyntaxError: The type cast expression is expected to be wrapped with parenthesis (1:15)"
+  ],
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 25,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 1,
+        "column": 25
+      }
+    },
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "ExpressionStatement",
+        "start": 0,
+        "end": 25,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 25
+          }
+        },
+        "expression": {
+          "type": "OptionalCallExpression",
+          "start": 0,
+          "end": 24,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 0
+            },
+            "end": {
+              "line": 1,
+              "column": 24
+            }
+          },
+          "callee": {
+            "type": "Identifier",
+            "start": 0,
+            "end": 8,
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 0
+              },
+              "end": {
+                "line": 1,
+                "column": 8
+              },
+              "identifierName": "funccall"
+            },
+            "name": "funccall"
+          },
+          "optional": true,
+          "arguments": [
+            {
+              "type": "Identifier",
+              "start": 11,
+              "end": 12,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 11
+                },
+                "end": {
+                  "line": 1,
+                  "column": 12
+                },
+                "identifierName": "a"
+              },
+              "name": "a"
+            },
+            {
+              "type": "TypeCastExpression",
+              "start": 14,
+              "end": 23,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 14
+                },
+                "end": {
+                  "line": 1,
+                  "column": 23
+                }
+              },
+              "expression": {
+                "type": "Identifier",
+                "start": 14,
+                "end": 15,
+                "loc": {
+                  "start": {
+                    "line": 1,
+                    "column": 14
+                  },
+                  "end": {
+                    "line": 1,
+                    "column": 15
+                  },
+                  "identifierName": "b"
+                },
+                "name": "b"
+              },
+              "typeAnnotation": {
+                "type": "TypeAnnotation",
+                "start": 15,
+                "end": 23,
+                "loc": {
+                  "start": {
+                    "line": 1,
+                    "column": 15
+                  },
+                  "end": {
+                    "line": 1,
+                    "column": 23
+                  }
+                },
+                "typeAnnotation": {
+                  "type": "StringTypeAnnotation",
+                  "start": 17,
+                  "end": 23,
+                  "loc": {
+                    "start": {
+                      "line": 1,
+                      "column": 17
+                    },
+                    "end": {
+                      "line": 1,
+                      "column": 23
+                    }
+                  }
+                }
+              }
+            }
+          ]
+        }
+      }
+    ],
+    "directives": []
+  }
+}