[parser] Disallow duplicate and undeclared private names (#10456)

* [parser] Add private names tracking to Scope

- Disallow duplicate private names
- Disallow undeclared private names

* Update tests

* Test all possible duplications

* Test undeclared private names

* Better error message for top-level private names

* Fix flow

* Update test262 whitelist

* Update fixtures

* Update flow whitelist

* Remove old output.json

* Move ClassScopeHandler to a separate class

* Make the code readable

packages/babel-generator/test/fixtures/types/ClassBody-ClassProperty/input.js

@@ -28,9 +28,9 @@ class Foo {
   foo = 0; bar = 1;
 
   #foo;
-  #foo = 1;
+  #foo2 = 1;
-  static #foo;
+  static #foo3;
-  static #foo = Foo.#foo;
+  static #foo4 = Foo.#foo;
 }
 
 class A1 {

packages/babel-generator/test/fixtures/types/ClassBody-ClassProperty/output.js

@@ -27,9 +27,9 @@ class Foo {
   foo = 0;
   bar = 1;
   #foo;
-  #foo = 1;
+  #foo2 = 1;
-  static #foo;
+  static #foo3;
-  static #foo = Foo.#foo;
+  static #foo4 = Foo.#foo;
 }
 
 class A1 {

packages/babel-generator/test/fixtures/types/ClassBody-MethodDefinition/input.js

@@ -6,13 +6,13 @@ class Foo {
   set foo(bar) {}
 
   async #foo() {}
-  #foo() {}
+  #foo2() {}
-  get #foo() {}
+  get #foo3() {}
-  set #foo(bar) {}
+  set #foo3(bar) {}
-  * #foo() {}
+  * #foo4() {}
-  async * #foo() {}
+  async * #foo5() {}
-  get #bar() {}
+  get #bar6() {}
-  set #baz(taz) {}
+  set #baz6(taz) {}
 
   static async foo() {}
   static foo() {}
@@ -23,13 +23,13 @@ class Foo {
   static * foo() {}
   static async * foo() {}
 
-  static #foo() {}
+  static #foo7() {}
-  static async #foo() {}
+  static async #foo8() {}
   static ["foo"]() {}
-  static get #foo() {}
+  static get #foo9() {}
-  static set #foo(taz) {}
+  static set #foo9(taz) {}
-  static * #foo() {}
+  static * #foo10() {}
-  static async * #foo() {}
+  static async * #foo11() {}
 
   get
   () {}

packages/babel-generator/test/fixtures/types/ClassBody-MethodDefinition/output.js

@@ -11,19 +11,19 @@ class Foo {
 
   async #foo() {}
 
-  #foo() {}
+  #foo2() {}
 
-  get #foo() {}
+  get #foo3() {}
 
-  set #foo(bar) {}
+  set #foo3(bar) {}
 
-  *#foo() {}
+  *#foo4() {}
 
-  async *#foo() {}
+  async *#foo5() {}
 
-  get #bar() {}
+  get #bar6() {}
 
-  set #baz(taz) {}
+  set #baz6(taz) {}
 
   static async foo() {}
 
@@ -41,19 +41,19 @@ class Foo {
 
   static async *foo() {}
 
-  static #foo() {}
+  static #foo7() {}
 
-  static async #foo() {}
+  static async #foo8() {}
 
   static ["foo"]() {}
 
-  static get #foo() {}
+  static get #foo9() {}
 
-  static set #foo(taz) {}
+  static set #foo9(taz) {}
 
-  static *#foo() {}
+  static *#foo10() {}
 
-  static async *#foo() {}
+  static async *#foo11() {}
 
   get() {}
 

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

@@ -4,12 +4,14 @@ import type { Options } from "../options";
 import type State from "../tokenizer/state";
 import type { PluginsMap } from "./index";
 import type ScopeHandler from "../util/scope";
+import type ClassScopeHandler from "../util/class-scope";
 
 export default class BaseParser {
   // Properties set by constructor in index.js
   options: Options;
   inModule: boolean;
   scope: ScopeHandler<*>;
+  classScope: ClassScopeHandler;
   plugins: PluginsMap;
   filename: ?string;
   sawUnambiguousESM: boolean = false;

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

@@ -612,15 +612,21 @@ export default class ExpressionParser extends LValParser {
         ? this.parseIdentifier(true)
         : this.parseMaybePrivateName();
       node.computed = computed;
-      if (
+
-        node.property.type === "PrivateName" &&
+      if (node.property.type === "PrivateName") {
-        node.object.type === "Super"
+        if (node.object.type === "Super") {
-      ) {
           this.raise(startPos, "Private fields can't be accessed on super");
         }
+        this.classScope.usePrivateName(
+          node.property.id.name,
+          node.property.start,
+        );
+      }
+
       if (computed) {
         this.expect(tt.bracketR);
       }
+
       if (state.optionalChainMember) {
         node.optional = optional;
         return this.finishNode(node, "OptionalMemberExpression");

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

@@ -7,6 +7,7 @@ import { getOptions } from "../options";
 import StatementParser from "./statement";
 import { SCOPE_ASYNC, SCOPE_PROGRAM } from "../util/scopeflags";
 import ScopeHandler from "../util/scope";
+import ClassScopeHandler from "../util/class-scope";
 
 export type PluginsMap = Map<string, { [string]: any }>;
 
@@ -25,6 +26,7 @@ export default class Parser extends StatementParser {
     this.options = options;
     this.inModule = this.options.sourceType === "module";
     this.scope = new ScopeHandler(this.raise.bind(this), this.inModule);
+    this.classScope = new ClassScopeHandler(this.raise.bind(this));
     this.plugins = pluginsMap(this.options.plugins);
     this.filename = options.sourceFilename;
   }

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

@@ -20,6 +20,11 @@ import {
   SCOPE_OTHER,
   SCOPE_SIMPLE_CATCH,
   SCOPE_SUPER,
+  CLASS_ELEMENT_OTHER,
+  CLASS_ELEMENT_INSTANCE_GETTER,
+  CLASS_ELEMENT_INSTANCE_SETTER,
+  CLASS_ELEMENT_STATIC_GETTER,
+  CLASS_ELEMENT_STATIC_SETTER,
   type BindingTypes,
 } from "../util/scopeflags";
 
@@ -1171,7 +1176,7 @@ export default class StatementParser extends ExpressionParser {
   }
 
   parseClassBody(constructorAllowsSuper: boolean): N.ClassBody {
-    this.state.classLevel++;
+    this.classScope.enter();
 
     const state = { hadConstructor: false };
     let decorators: N.Decorator[] = [];
@@ -1231,7 +1236,7 @@ export default class StatementParser extends ExpressionParser {
       );
     }
 
-    this.state.classLevel--;
+    this.classScope.exit();
 
     return this.finishNode(classBody, "ClassBody");
   }
@@ -1514,7 +1519,15 @@ export default class StatementParser extends ExpressionParser {
     prop: N.ClassPrivateProperty,
   ) {
     this.expectPlugin("classPrivateProperties", prop.key.start);
-    classBody.body.push(this.parseClassPrivateProperty(prop));
+
+    const node = this.parseClassPrivateProperty(prop);
+    classBody.body.push(node);
+
+    this.classScope.declarePrivateName(
+      node.key.id.name,
+      CLASS_ELEMENT_OTHER,
+      node.key.start,
+    );
   }
 
   pushClassMethod(
@@ -1545,8 +1558,8 @@ export default class StatementParser extends ExpressionParser {
     isAsync: boolean,
   ): void {
     this.expectPlugin("classPrivateMethods", method.key.start);
-    classBody.body.push(
+
-      this.parseMethod(
+    const node = this.parseMethod(
       method,
       isGenerator,
       isAsync,
@@ -1554,8 +1567,20 @@ export default class StatementParser extends ExpressionParser {
       false,
       "ClassPrivateMethod",
       true,
-      ),
     );
+    classBody.body.push(node);
+
+    const kind =
+      node.kind === "get"
+        ? node.static
+          ? CLASS_ELEMENT_STATIC_GETTER
+          : CLASS_ELEMENT_INSTANCE_GETTER
+        : node.kind === "set"
+        ? node.static
+          ? CLASS_ELEMENT_STATIC_SETTER
+          : CLASS_ELEMENT_INSTANCE_SETTER
+        : CLASS_ELEMENT_OTHER;
+    this.classScope.declarePrivateName(node.key.id.name, kind, node.key.start);
   }
 
   // Overridden in typescript.js

packages/babel-parser/src/tokenizer/index.js

@@ -391,14 +391,8 @@ export default class Tokenizer extends LocationParser {
     }
 
     if (
-      (this.hasPlugin("classPrivateProperties") ||
+      this.hasPlugin("classPrivateProperties") ||
-        this.hasPlugin("classPrivateMethods")) &&
+      this.hasPlugin("classPrivateMethods") ||
-      this.state.classLevel > 0
-    ) {
-      ++this.state.pos;
-      this.finishToken(tt.hash);
-      return;
-    } else if (
       this.getPluginOption("pipelineOperator", "proposal") === "smart"
     ) {
       this.finishOp(tt.hash, 1);

packages/babel-parser/src/tokenizer/state.js

@@ -77,9 +77,6 @@ export default class State {
   soloAwait: boolean = false;
   inFSharpPipelineDirectBody: boolean = false;
 
-  // Check whether we are in a (nested) class or not.
-  classLevel: number = 0;
-
   // Labels in scope.
   labels: Array<{
     kind: ?("loop" | "switch"),

packages/babel-parser/src/util/class-scope.js

@@ -0,0 +1,113 @@
+// @flow
+
+import {
+  CLASS_ELEMENT_KIND_ACCESSOR,
+  CLASS_ELEMENT_FLAG_STATIC,
+  type ClassElementTypes,
+} from "./scopeflags";
+
+export class ClassScope {
+  // A list of private named declared in the current class
+  privateNames: Set<string> = new Set();
+
+  // A list of private getters of setters without their counterpart
+  loneAccessors: Map<string, ClassElementTypes> = new Map();
+
+  // A list of private names used before being defined, mapping to
+  // their position.
+  undefinedPrivateNames: Map<string, number> = new Map();
+}
+
+type raiseFunction = (number, string) => void;
+
+export default class ClassScopeHandler {
+  stack: Array<ClassScope> = [];
+  raise: raiseFunction;
+  undefinedPrivateNames: Map<string, number> = new Map();
+
+  constructor(raise: raiseFunction) {
+    this.raise = raise;
+  }
+
+  current(): ClassScope {
+    return this.stack[this.stack.length - 1];
+  }
+
+  enter() {
+    this.stack.push(new ClassScope());
+  }
+
+  exit() {
+    const oldClassScope = this.stack.pop();
+
+    // Migrate the usage of not yet defined private names to the outer
+    // class scope, or raise an error if we reached the top-level scope.
+
+    const current = this.current();
+
+    // Array.from is needed because this is compiled to an array-like for loop
+    for (const [name, pos] of Array.from(oldClassScope.undefinedPrivateNames)) {
+      if (current) {
+        if (!current.undefinedPrivateNames.has(name)) {
+          current.undefinedPrivateNames.set(name, pos);
+        }
+      } else {
+        this.raiseUndeclaredPrivateName(name, pos);
+      }
+    }
+  }
+
+  declarePrivateName(
+    name: string,
+    elementType: ClassElementTypes,
+    pos: number,
+  ) {
+    const classScope = this.current();
+    let redefined = classScope.privateNames.has(name);
+
+    if (elementType & CLASS_ELEMENT_KIND_ACCESSOR) {
+      const accessor = redefined && classScope.loneAccessors.get(name);
+      if (accessor) {
+        const oldStatic = accessor & CLASS_ELEMENT_FLAG_STATIC;
+        const newStatic = elementType & CLASS_ELEMENT_FLAG_STATIC;
+
+        const oldKind = accessor & CLASS_ELEMENT_KIND_ACCESSOR;
+        const newKind = elementType & CLASS_ELEMENT_KIND_ACCESSOR;
+
+        // The private name can be duplicated only if it is used by
+        // two accessors with different kind (get and set), and if
+        // they have the same placement (static or not).
+        redefined = oldKind === newKind || oldStatic !== newStatic;
+
+        if (!redefined) classScope.loneAccessors.delete(name);
+      } else if (!redefined) {
+        classScope.loneAccessors.set(name, elementType);
+      }
+    }
+
+    if (redefined) {
+      this.raise(pos, `Duplicate private name #${name}`);
+    }
+
+    classScope.privateNames.add(name);
+    classScope.undefinedPrivateNames.delete(name);
+  }
+
+  usePrivateName(name: string, pos: number) {
+    let classScope;
+    for (classScope of this.stack) {
+      if (classScope.privateNames.has(name)) return;
+    }
+
+    if (classScope) {
+      classScope.undefinedPrivateNames.set(name, pos);
+    } else {
+      // top-level
+      this.raiseUndeclaredPrivateName(name, pos);
+    }
+  }
+
+  raiseUndeclaredPrivateName(name: string, pos: number) {
+    this.raise(pos, `Private name #${name} is not defined`);
+  }
+}

packages/babel-parser/src/util/scope.js

@@ -43,6 +43,7 @@ export default class ScopeHandler<IScope: Scope = Scope> {
   raise: raiseFunction;
   inModule: boolean;
   undefinedExports: Map<string, number> = new Map();
+  undefinedPrivateNames: Map<string, number> = new Map();
 
   constructor(raise: raiseFunction, inModule: boolean) {
     this.raise = raise;

packages/babel-parser/src/util/scopeflags.js

@@ -84,3 +84,23 @@ export type BindingTypes =
   | typeof BIND_TS_ENUM
   | typeof BIND_TS_AMBIENT
   | typeof BIND_TS_NAMESPACE;
+
+// prettier-ignore
+export const CLASS_ELEMENT_FLAG_STATIC = 0b1_00,
+             CLASS_ELEMENT_KIND_GETTER = 0b0_10,
+             CLASS_ELEMENT_KIND_SETTER = 0b0_01,
+             CLASS_ELEMENT_KIND_ACCESSOR = CLASS_ELEMENT_KIND_GETTER | CLASS_ELEMENT_KIND_SETTER;
+
+// prettier-ignore
+export const CLASS_ELEMENT_STATIC_GETTER   = CLASS_ELEMENT_KIND_GETTER | CLASS_ELEMENT_FLAG_STATIC,
+             CLASS_ELEMENT_STATIC_SETTER   = CLASS_ELEMENT_KIND_SETTER | CLASS_ELEMENT_FLAG_STATIC,
+             CLASS_ELEMENT_INSTANCE_GETTER = CLASS_ELEMENT_KIND_GETTER,
+             CLASS_ELEMENT_INSTANCE_SETTER = CLASS_ELEMENT_KIND_SETTER,
+             CLASS_ELEMENT_OTHER           = 0;
+
+export type ClassElementTypes =
+  | typeof CLASS_ELEMENT_STATIC_GETTER
+  | typeof CLASS_ELEMENT_STATIC_SETTER
+  | typeof CLASS_ELEMENT_INSTANCE_GETTER
+  | typeof CLASS_ELEMENT_INSTANCE_SETTER
+  | typeof CLASS_ELEMENT_OTHER;

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/README.md

@@ -0,0 +1,26 @@
+These tests have been generated using the following script:
+
+```js
+var feat = {
+  "field": "#x = 0;",
+  "method": "#x() {}",
+  "get": "get #x() {}",
+  "set": "set #x(_) {}",
+};
+var placement = {
+  "static": "static ",
+  "instance": ""
+}
+
+for (var f1 in feat) for (var f2 in feat) for (var p1 in placement) for (var p2 in placement) {
+  var code = `class A {
+  ${placement[p1]}${feat[f1]}
+  ${placement[p2]}${feat[f2]}
+}`;
+  var name = `${p1}-${f1}-${p2}-${f2}`;
+  var folder = "packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/" + name;
+
+  if (!fs.existsSync(folder)) fs.mkdirSync(folder);
+  fs.writeFileSync(folder + "/input.js", code);
+}
+```

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-instance-field/input.js

@@ -0,0 +1,4 @@
+class A {
+  #x = 0;
+  #x = 0;
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-instance-field/output.json

@@ -0,0 +1,224 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 31,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 4,
+      "column": 1
+    }
+  },
+  "errors": [
+    "SyntaxError: Duplicate private name #x (3:2)"
+  ],
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 31,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 4,
+        "column": 1
+      }
+    },
+    "sourceType": "script",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "ClassDeclaration",
+        "start": 0,
+        "end": 31,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 4,
+            "column": 1
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 6,
+          "end": 7,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 6
+            },
+            "end": {
+              "line": 1,
+              "column": 7
+            },
+            "identifierName": "A"
+          },
+          "name": "A"
+        },
+        "superClass": null,
+        "body": {
+          "type": "ClassBody",
+          "start": 8,
+          "end": 31,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 8
+            },
+            "end": {
+              "line": 4,
+              "column": 1
+            }
+          },
+          "body": [
+            {
+              "type": "ClassPrivateProperty",
+              "start": 12,
+              "end": 19,
+              "loc": {
+                "start": {
+                  "line": 2,
+                  "column": 2
+                },
+                "end": {
+                  "line": 2,
+                  "column": 9
+                }
+              },
+              "static": false,
+              "key": {
+                "type": "PrivateName",
+                "start": 12,
+                "end": 14,
+                "loc": {
+                  "start": {
+                    "line": 2,
+                    "column": 2
+                  },
+                  "end": {
+                    "line": 2,
+                    "column": 4
+                  }
+                },
+                "id": {
+                  "type": "Identifier",
+                  "start": 13,
+                  "end": 14,
+                  "loc": {
+                    "start": {
+                      "line": 2,
+                      "column": 3
+                    },
+                    "end": {
+                      "line": 2,
+                      "column": 4
+                    },
+                    "identifierName": "x"
+                  },
+                  "name": "x"
+                }
+              },
+              "value": {
+                "type": "NumericLiteral",
+                "start": 17,
+                "end": 18,
+                "loc": {
+                  "start": {
+                    "line": 2,
+                    "column": 7
+                  },
+                  "end": {
+                    "line": 2,
+                    "column": 8
+                  }
+                },
+                "extra": {
+                  "rawValue": 0,
+                  "raw": "0"
+                },
+                "value": 0
+              }
+            },
+            {
+              "type": "ClassPrivateProperty",
+              "start": 22,
+              "end": 29,
+              "loc": {
+                "start": {
+                  "line": 3,
+                  "column": 2
+                },
+                "end": {
+                  "line": 3,
+                  "column": 9
+                }
+              },
+              "static": false,
+              "key": {
+                "type": "PrivateName",
+                "start": 22,
+                "end": 24,
+                "loc": {
+                  "start": {
+                    "line": 3,
+                    "column": 2
+                  },
+                  "end": {
+                    "line": 3,
+                    "column": 4
+                  }
+                },
+                "id": {
+                  "type": "Identifier",
+                  "start": 23,
+                  "end": 24,
+                  "loc": {
+                    "start": {
+                      "line": 3,
+                      "column": 3
+                    },
+                    "end": {
+                      "line": 3,
+                      "column": 4
+                    },
+                    "identifierName": "x"
+                  },
+                  "name": "x"
+                }
+              },
+              "value": {
+                "type": "NumericLiteral",
+                "start": 27,
+                "end": 28,
+                "loc": {
+                  "start": {
+                    "line": 3,
+                    "column": 7
+                  },
+                  "end": {
+                    "line": 3,
+                    "column": 8
+                  }
+                },
+                "extra": {
+                  "rawValue": 0,
+                  "raw": "0"
+                },
+                "value": 0
+              }
+            }
+          ]
+        }
+      }
+    ],
+    "directives": []
+  }
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-instance-get/input.js

@@ -0,0 +1,4 @@
+class A {
+  #x = 0;
+  get #x() {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-instance-get/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["classPrivateProperties", "classPrivateMethods"]
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-instance-get/output.json

@@ -0,0 +1,227 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 35,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 4,
+      "column": 1
+    }
+  },
+  "errors": [
+    "SyntaxError: Duplicate private name #x (3:6)"
+  ],
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 35,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 4,
+        "column": 1
+      }
+    },
+    "sourceType": "script",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "ClassDeclaration",
+        "start": 0,
+        "end": 35,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 4,
+            "column": 1
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 6,
+          "end": 7,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 6
+            },
+            "end": {
+              "line": 1,
+              "column": 7
+            },
+            "identifierName": "A"
+          },
+          "name": "A"
+        },
+        "superClass": null,
+        "body": {
+          "type": "ClassBody",
+          "start": 8,
+          "end": 35,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 8
+            },
+            "end": {
+              "line": 4,
+              "column": 1
+            }
+          },
+          "body": [
+            {
+              "type": "ClassPrivateProperty",
+              "start": 12,
+              "end": 19,
+              "loc": {
+                "start": {
+                  "line": 2,
+                  "column": 2
+                },
+                "end": {
+                  "line": 2,
+                  "column": 9
+                }
+              },
+              "static": false,
+              "key": {
+                "type": "PrivateName",
+                "start": 12,
+                "end": 14,
+                "loc": {
+                  "start": {
+                    "line": 2,
+                    "column": 2
+                  },
+                  "end": {
+                    "line": 2,
+                    "column": 4
+                  }
+                },
+                "id": {
+                  "type": "Identifier",
+                  "start": 13,
+                  "end": 14,
+                  "loc": {
+                    "start": {
+                      "line": 2,
+                      "column": 3
+                    },
+                    "end": {
+                      "line": 2,
+                      "column": 4
+                    },
+                    "identifierName": "x"
+                  },
+                  "name": "x"
+                }
+              },
+              "value": {
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+              "async": false,
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packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-instance-method/input.js

@@ -0,0 +1,4 @@
+class A {
+  #x = 0;
+  #x() {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-instance-method/options.json

@@ -0,0 +1,3 @@
+{
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+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-instance-method/output.json

@@ -0,0 +1,226 @@
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packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-instance-set/input.js

@@ -0,0 +1,4 @@
+class A {
+  #x = 0;
+  set #x(_) {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-instance-set/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["classPrivateProperties", "classPrivateMethods"]
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-instance-set/output.json

@@ -0,0 +1,245 @@
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packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-static-field/input.js

@@ -0,0 +1,4 @@
+class A {
+  #x = 0;
+  static #x = 0;
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-static-field/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["classPrivateProperties", "classPrivateMethods"]
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-static-field/output.json

@@ -0,0 +1,224 @@
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packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-static-get/input.js

@@ -0,0 +1,4 @@
+class A {
+  #x = 0;
+  static get #x() {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-static-get/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["classPrivateProperties", "classPrivateMethods"]
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-static-get/output.json

@@ -0,0 +1,227 @@
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+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-static-method/input.js

@@ -0,0 +1,4 @@
+class A {
+  #x = 0;
+  static #x() {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-static-method/options.json

@@ -0,0 +1,3 @@
+{
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+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-static-method/output.json

@@ -0,0 +1,226 @@
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packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-static-set/input.js

@@ -0,0 +1,4 @@
+class A {
+  #x = 0;
+  static set #x(_) {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-static-set/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["classPrivateProperties", "classPrivateMethods"]
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-field-static-set/output.json

@@ -0,0 +1,245 @@
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packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-instance-field/input.js

@@ -0,0 +1,4 @@
+class A {
+  get #x() {}
+  #x = 0;
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-instance-field/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["classPrivateProperties", "classPrivateMethods"]
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-instance-field/output.json

@@ -0,0 +1,227 @@
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packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-instance-get/input.js

@@ -0,0 +1,4 @@
+class A {
+  get #x() {}
+  get #x() {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-instance-get/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["classPrivateProperties", "classPrivateMethods"]
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-instance-get/output.json

@@ -0,0 +1,230 @@
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packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-instance-method/input.js

@@ -0,0 +1,4 @@
+class A {
+  get #x() {}
+  #x() {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-instance-method/options.json

@@ -0,0 +1,3 @@
+{
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+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-instance-method/output.json

@@ -0,0 +1,229 @@
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packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-instance-set/input.js

@@ -0,0 +1,4 @@
+class A {
+  get #x() {}
+  set #x(_) {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-instance-set/output.json

@@ -0,0 +1,245 @@
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packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-static-field/input.js

@@ -0,0 +1,4 @@
+class A {
+  get #x() {}
+  static #x = 0;
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-static-field/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["classPrivateProperties", "classPrivateMethods"]
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-static-field/output.json

@@ -0,0 +1,227 @@
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packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-static-get/input.js

@@ -0,0 +1,4 @@
+class A {
+  get #x() {}
+  static get #x() {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-static-get/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["classPrivateProperties", "classPrivateMethods"]
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-static-get/output.json

@@ -0,0 +1,230 @@
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+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-static-method/input.js

@@ -0,0 +1,4 @@
+class A {
+  get #x() {}
+  static #x() {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-static-method/options.json

@@ -0,0 +1,3 @@
+{
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+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-static-method/output.json

@@ -0,0 +1,229 @@
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packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-static-set/input.js

@@ -0,0 +1,4 @@
+class A {
+  get #x() {}
+  static set #x(_) {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-static-set/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["classPrivateProperties", "classPrivateMethods"]
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-get-static-set/output.json

@@ -0,0 +1,248 @@
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packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-instance-field/input.js

@@ -0,0 +1,4 @@
+class A {
+  #x() {}
+  #x = 0;
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-instance-field/options.json

@@ -0,0 +1,3 @@
+{
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+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-instance-field/output.json

@@ -0,0 +1,226 @@
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packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-instance-get/input.js

@@ -0,0 +1,4 @@
+class A {
+  #x() {}
+  get #x() {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-instance-get/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["classPrivateProperties", "classPrivateMethods"]
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-instance-get/output.json

@@ -0,0 +1,229 @@
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+        }
+      }
+    ],
+    "directives": []
+  }
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-instance-method/input.js

@@ -0,0 +1,4 @@
+class A {
+  #x() {}
+  #x() {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-instance-method/options.json

@@ -0,0 +1,3 @@
+{
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+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-instance-method/output.json

@@ -0,0 +1,228 @@
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+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-instance-set/input.js

@@ -0,0 +1,4 @@
+class A {
+  #x() {}
+  set #x(_) {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-instance-set/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["classPrivateProperties", "classPrivateMethods"]
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-instance-set/output.json

@@ -0,0 +1,247 @@
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packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-static-field/input.js

@@ -0,0 +1,4 @@
+class A {
+  #x() {}
+  static #x = 0;
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-static-field/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["classPrivateProperties", "classPrivateMethods"]
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-static-field/output.json

@@ -0,0 +1,226 @@
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+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-static-get/input.js

@@ -0,0 +1,4 @@
+class A {
+  #x() {}
+  static get #x() {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-static-get/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["classPrivateProperties", "classPrivateMethods"]
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-static-get/output.json

@@ -0,0 +1,229 @@
+{
+  "type": "File",
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+  "end": 42,
+  "loc": {
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+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-static-method/input.js

@@ -0,0 +1,4 @@
+class A {
+  #x() {}
+  static #x() {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-static-method/options.json

@@ -0,0 +1,3 @@
+{
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+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-static-method/output.json

@@ -0,0 +1,228 @@
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packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-static-set/input.js

@@ -0,0 +1,4 @@
+class A {
+  #x() {}
+  static set #x(_) {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-static-set/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["classPrivateProperties", "classPrivateMethods"]
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-method-static-set/output.json

@@ -0,0 +1,247 @@
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packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-set-instance-field/input.js

@@ -0,0 +1,4 @@
+class A {
+  set #x(_) {}
+  #x = 0;
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-set-instance-field/options.json

@@ -0,0 +1,3 @@
+{
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+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-set-instance-field/output.json

@@ -0,0 +1,245 @@
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packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-set-instance-get/input.js

@@ -0,0 +1,4 @@
+class A {
+  set #x(_) {}
+  get #x() {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-set-instance-get/output.json

@@ -0,0 +1,245 @@
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packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-set-instance-method/input.js

@@ -0,0 +1,4 @@
+class A {
+  set #x(_) {}
+  #x() {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-set-instance-method/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["classPrivateProperties", "classPrivateMethods"]
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-set-instance-method/output.json

@@ -0,0 +1,247 @@
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+              }
+            }
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+  }
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-set-instance-set/input.js

@@ -0,0 +1,4 @@
+class A {
+  set #x(_) {}
+  set #x(_) {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-set-instance-set/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["classPrivateProperties", "classPrivateMethods"]
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-set-instance-set/output.json

@@ -0,0 +1,266 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 41,
+  "loc": {
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+      "column": 1
+    }
+  },
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+    "SyntaxError: Duplicate private name #x (3:6)"
+  ],
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+    "start": 0,
+    "end": 41,
+    "loc": {
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+    "interpreter": null,
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+              "column": 1
+            }
+          },
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+                }
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+              "async": false,
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+                  "end": 35,
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+                    "identifierName": "_"
+                  },
+                  "name": "_"
+                }
+              ],
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+  }
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-set-static-field/input.js

@@ -0,0 +1,4 @@
+class A {
+  set #x(_) {}
+  static #x = 0;
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-set-static-field/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["classPrivateProperties", "classPrivateMethods"]
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-set-static-field/output.json

@@ -0,0 +1,245 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 43,
+  "loc": {
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+      "column": 0
+    },
+    "end": {
+      "line": 4,
+      "column": 1
+    }
+  },
+  "errors": [
+    "SyntaxError: Duplicate private name #x (3:9)"
+  ],
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 43,
+    "loc": {
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+                  "end": 36,
+                  "loc": {
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+                      "column": 11
+                    },
+                    "identifierName": "x"
+                  },
+                  "name": "x"
+                }
+              },
+              "value": {
+                "type": "NumericLiteral",
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+                "end": 40,
+                "loc": {
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+                    "line": 3,
+                    "column": 14
+                  },
+                  "end": {
+                    "line": 3,
+                    "column": 15
+                  }
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+                  "raw": "0"
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+              }
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+          ]
+        }
+      }
+    ],
+    "directives": []
+  }
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-set-static-get/input.js

@@ -0,0 +1,4 @@
+class A {
+  set #x(_) {}
+  static get #x() {}
+}

packages/babel-parser/test/fixtures/experimental/class-private-names-duplicated/instance-set-static-get/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["classPrivateProperties", "classPrivateMethods"]
+}