Add tests for stage 3 proposal "private fields in" (#2963)

features.txt

@@ -299,3 +299,7 @@ __setter__
 
 IsHTMLDDA
 host-gc-required
+
+# Ergonomic brand checks for Private Fields
+# https://github.com/tc39/proposal-private-fields-in-in
+class-fields-private-in

test/language/expressions/in/private-field-in.js

@@ -0,0 +1,26 @@
+// Copyright 2021 the V8 project authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Requires the `In` parsing parameter
+info: |
+  Syntax
+    RelationalExpression[In, Yield, Await]:
+    [...]
+    [+In]PrivateIdentifier in ShiftExpression[?Yield, ?Await]
+esid: sec-relational-operators-runtime-semantics-evaluation
+negative:
+  phase: parse
+  type: SyntaxError
+features: [class-fields-private, class-fields-private-in]
+---*/
+
+$DONOTEVALUATE();
+
+class C {
+  #field;
+
+  constructor() {
+    for (#field in value;;) break;
+  }
+}

test/language/expressions/in/private-field-invalid-assignment-target.js

@@ -0,0 +1,31 @@
+// Copyright 2021 the V8 project authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Rejected as assignment target
+info: |
+  12.10.5 Static Semantics: AllPrivateIdentifiersValid
+
+  AllPrivateIdentifiersValid is an abstract operation which takes names as an argument.
+
+  RelationalExpression:PrivateIdentifierinShiftExpression
+
+  1. If StringValue of PrivateIdentifier is in names, return true.
+  2. Return false.
+
+esid: sec-relational-operators-runtime-semantics-evaluation
+negative:
+  phase: parse
+  type: SyntaxError
+features: [class-fields-private, class-fields-private-in]
+---*/
+
+$DONOTEVALUATE();
+
+class C {
+  #field;
+
+  constructor() {
+    #field in {} = 0;
+  }
+}

test/language/expressions/in/private-field-invalid-identifier-complex.js

@@ -0,0 +1,31 @@
+// Copyright 2021 the V8 project authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Invalid private identifier - complex case
+info: |
+  12.10.5 Static Semantics: AllPrivateIdentifiersValid
+
+  AllPrivateIdentifiersValid is an abstract operation which takes names as an argument.
+
+  RelationalExpression:PrivateIdentifierinShiftExpression
+
+  1. If StringValue of PrivateIdentifier is in names, return true.
+  2. Return false.
+
+esid: sec-relational-operators-runtime-semantics-evaluation
+negative:
+  phase: parse
+  type: SyntaxError
+features: [class-fields-private, class-fields-private-in]
+---*/
+
+$DONOTEVALUATE();
+
+class C {
+  #a;
+
+  constructor() {
+    #b in {};
+  }
+}

test/language/expressions/in/private-field-invalid-identifier-simple.js

@@ -0,0 +1,25 @@
+// Copyright 2021 the V8 project authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Invalid private identifier - simple case
+info: |
+  12.10.5 Static Semantics: AllPrivateIdentifiersValid
+
+  AllPrivateIdentifiersValid is an abstract operation which takes names as an argument.
+
+  RelationalExpression:PrivateIdentifierinShiftExpression
+
+  1. If StringValue of PrivateIdentifier is in names, return true.
+  2. Return false.
+
+esid: sec-relational-operators-runtime-semantics-evaluation
+negative:
+  phase: parse
+  type: SyntaxError
+features: [class-fields-private, class-fields-private-in]
+---*/
+
+$DONOTEVALUATE();
+
+#name in {};

test/language/expressions/in/private-field-invalid-rhs.js

@@ -0,0 +1,26 @@
+// Copyright 2021 the V8 project authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Syntactic grammar restricts right-hand side
+info: |
+  Syntax
+    RelationalExpression[In, Yield, Await]:
+    [...]
+    [+In]PrivateIdentifier in ShiftExpression[?Yield, ?Await]
+esid: sec-relational-operators-runtime-semantics-evaluation
+negative:
+  phase: parse
+  type: SyntaxError
+features: [class-fields-private, class-fields-private-in]
+---*/
+
+$DONOTEVALUATE();
+
+class C {
+  #field;
+
+  constructor() {
+    #field in () => {};
+  }
+}

test/language/expressions/in/private-field-presence-accessor-shadowed.js

@@ -0,0 +1,47 @@
+// Copyright 2021 the V8 project authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Value when private name describes an accessor method
+info: |
+  7. Let privateName be ? GetValue(privateNameBinding).
+  8. Assert: privateName is a Private Name.
+  [...]
+  10. Else,
+      a. Assert: privateName.[[Kind]] is "method" or "accessor".
+      b. If PrivateBrandCheck(rval, privateName) is not an abrupt completion,
+         then return true.
+  11. Return false.
+esid: sec-relational-operators-runtime-semantics-evaluation
+features: [class-static-methods-private, class-fields-private-in]
+---*/
+
+let Child;
+let parentCount = 0;
+let childCount = 0;
+
+class Parent {
+  get #accessor() {
+    parentCount += 1;
+  }
+
+  static init() {
+    Child = class {
+      get #accessor() {
+        childCount += 1;
+      }
+
+      static isNameIn(value) {
+        return #accessor in value;
+      }
+    };
+  }
+}
+
+Parent.init();
+
+assert.sameValue(Child.isNameIn(new Parent()), false);
+assert.sameValue(parentCount, 0, 'parent accessor not invoked');
+assert.sameValue(Child.isNameIn(new Child()), true);
+assert.sameValue(childCount, 0, 'child accessor not invoked');
+

test/language/expressions/in/private-field-presence-accessor.js

@@ -0,0 +1,33 @@
+// Copyright 2021 the V8 project authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Value when private name describes an accessor method
+info: |
+  7. Let privateName be ? GetValue(privateNameBinding).
+  8. Assert: privateName is a Private Name.
+  [...]
+  10. Else,
+      a. Assert: privateName.[[Kind]] is "method" or "accessor".
+      b. If PrivateBrandCheck(rval, privateName) is not an abrupt completion,
+         then return true.
+  11. Return false.
+esid: sec-relational-operators-runtime-semantics-evaluation
+features: [class-static-methods-private, class-fields-private-in]
+---*/
+
+let count = 0;
+
+class Class {
+  get #accessor() {
+    count += 1;
+  }
+
+  static isNameIn(value) {
+    return #accessor in value;
+  }
+}
+
+assert.sameValue(Class.isNameIn({}), false);
+assert.sameValue(Class.isNameIn(new Class()), true);
+assert.sameValue(count, 0);

test/language/expressions/in/private-field-presence-field-shadowed.js

@@ -0,0 +1,36 @@
+// Copyright 2021 the V8 project authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Value when private name describes a field
+info: |
+  7. Let privateName be ? GetValue(privateNameBinding).
+  8. Assert: privateName is a Private Name.
+  9. If privateName.[[Kind]] is "field",
+     a. If ! PrivateFieldFind(privateName, rval) is not empty, then return true.
+  [...]
+  11. Return false.
+esid: sec-relational-operators-runtime-semantics-evaluation
+features: [class-fields-private, class-fields-private-in]
+---*/
+
+let Child;
+
+class Parent {
+  #field;
+
+  static init() {
+    Child = class {
+      #field;
+
+      static isNameIn(value) {
+        return #field in value;
+      }
+    };
+  }
+}
+
+Parent.init();
+
+assert.sameValue(Child.isNameIn(new Parent()), false);
+assert.sameValue(Child.isNameIn(new Child()), true);

test/language/expressions/in/private-field-presence-field.js

@@ -0,0 +1,26 @@
+// Copyright 2021 the V8 project authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Value when private name describes a field
+info: |
+  7. Let privateName be ? GetValue(privateNameBinding).
+  8. Assert: privateName is a Private Name.
+  9. If privateName.[[Kind]] is "field",
+     a. If ! PrivateFieldFind(privateName, rval) is not empty, then return true.
+  [...]
+  11. Return false.
+esid: sec-relational-operators-runtime-semantics-evaluation
+features: [class-fields-private, class-fields-private-in]
+---*/
+
+class Class {
+  #field;
+
+  static isNameIn(value) {
+    return #field in value;
+  }
+}
+
+assert.sameValue(Class.isNameIn({}), false);
+assert.sameValue(Class.isNameIn(new Class()), true);

test/language/expressions/in/private-field-presence-method-shadowed.js

@@ -0,0 +1,46 @@
+// Copyright 2021 the V8 project authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Value when private name describes a method
+info: |
+  7. Let privateName be ? GetValue(privateNameBinding).
+  8. Assert: privateName is a Private Name.
+  [...]
+  10. Else,
+      a. Assert: privateName.[[Kind]] is "method" or "accessor".
+      b. If PrivateBrandCheck(rval, privateName) is not an abrupt completion,
+         then return true.
+  11. Return false.
+esid: sec-relational-operators-runtime-semantics-evaluation
+features: [class-methods-private, class-fields-private-in]
+---*/
+
+let Child;
+let parentCount = 0;
+let childCount = 0;
+
+class Parent {
+  #method() {
+    parentCount += 1;
+  }
+
+  static init() {
+    Child = class {
+      #method() {
+        childCount += 1;
+      }
+
+      static isNameIn(value) {
+        return #method in value;
+      }
+    };
+  }
+}
+
+Parent.init();
+
+assert.sameValue(Child.isNameIn(new Parent()), false);
+assert.sameValue(parentCount, 0, 'parent method not invoked');
+assert.sameValue(Child.isNameIn(new Child()), true);
+assert.sameValue(childCount, 0, 'child method not invoked');

test/language/expressions/in/private-field-presence-method.js

@@ -0,0 +1,33 @@
+// Copyright 2021 the V8 project authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Value when private name describes a method
+info: |
+  7. Let privateName be ? GetValue(privateNameBinding).
+  8. Assert: privateName is a Private Name.
+  [...]
+  10. Else,
+      a. Assert: privateName.[[Kind]] is "method" or "accessor".
+      b. If PrivateBrandCheck(rval, privateName) is not an abrupt completion,
+         then return true.
+  11. Return false.
+esid: sec-relational-operators-runtime-semantics-evaluation
+features: [class-methods-private, class-fields-private-in]
+---*/
+
+let count = 0;
+
+class Class {
+  #method() {
+    count += 1;
+  }
+
+  static isNameIn(value) {
+    return #method in value;
+  }
+}
+
+assert.sameValue(Class.isNameIn({}), false);
+assert.sameValue(Class.isNameIn(new Class()), true);
+assert.sameValue(count, 0);

test/language/expressions/in/private-field-rhs-await-absent.js

@@ -0,0 +1,39 @@
+// Copyright 2021 the V8 project authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Parsing observes the `Await` production parameter when absent
+info: |
+  Syntax
+    RelationalExpression[In, Yield, Await]:
+    [...]
+    [+In]PrivateIdentifier in ShiftExpression[?Yield, ?Await]
+
+  [...]
+
+  1. Let privateIdentifier be the StringValue of PrivateIdentifier.
+  2. Let rref be the result of evaluating ShiftExpression.
+  3. Let rval be ? GetValue(rref).
+  4. If Type(rval) is not Object, throw a TypeError exception.
+esid: sec-relational-operators-runtime-semantics-evaluation
+features: [class-fields-private, class-fields-private-in]
+---*/
+
+let value;
+function await() {
+  return value;
+}
+
+class C {
+  #field;
+
+  static isNameIn() {
+    return #field in await(null);
+  }
+}
+
+value = new C();
+assert.sameValue(C.isNameIn(), true);
+
+value = {};
+assert.sameValue(C.isNameIn(), false);

test/language/expressions/in/private-field-rhs-await-present.js

@@ -0,0 +1,39 @@
+// Copyright 2021 the V8 project authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Parsing observes the `Await` production parameter when present
+info: |
+  Syntax
+    RelationalExpression[In, Yield, Await]:
+    [...]
+    [+In]PrivateIdentifier in ShiftExpression[?Yield, ?Await]
+
+  [...]
+
+  1. Let privateIdentifier be the StringValue of PrivateIdentifier.
+  2. Let rref be the result of evaluating ShiftExpression.
+  3. Let rval be ? GetValue(rref).
+  4. If Type(rval) is not Object, throw a TypeError exception.
+esid: sec-relational-operators-runtime-semantics-evaluation
+features: [class-fields-private, class-fields-private-in]
+flags: [async]
+---*/
+
+class C {
+  #field;
+
+  static async isNameIn(value) {
+    return #field in await(value);
+  }
+}
+
+C.isNameIn(new C())
+  .then(function(result) {
+    assert.sameValue(result, true);
+
+    return C.isNameIn({});
+  })
+  .then(function(result) {
+    assert.sameValue(result, false);
+  }).then($DONE, $DONE);

test/language/expressions/in/private-field-rhs-non-object.js

@@ -0,0 +1,51 @@
+// Copyright 2021 the V8 project authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Algorithm interrupted by non-object right-hand side
+info: |
+  Syntax
+    RelationalExpression[In, Yield, Await]:
+    [...]
+    [+In]PrivateIdentifier in ShiftExpression[?Yield, ?Await]
+
+  [...]
+
+  1. Let privateIdentifier be the StringValue of PrivateIdentifier.
+  2. Let rref be the result of evaluating ShiftExpression.
+  3. Let rval be ? GetValue(rref).
+  4. If Type(rval) is not Object, throw a TypeError exception.
+esid: sec-relational-operators-runtime-semantics-evaluation
+features: [class-fields-private, class-fields-private-in]
+---*/
+
+let caught = null;
+
+class C {
+  #field;
+
+  constructor() {
+    try {
+      /**
+       * Using a ShiftExpression to produce the non-object value verifies that
+       * the implementation uses the operator precedence implied by the
+       * syntactic grammar. In other words, the following statement should be
+       * interpreted as:
+       *
+       *     #field in ({} << 0);
+       *
+       * ...rather than:
+       *
+       *     (#field in {}) << 0;
+       */
+      #field in {} << 0;
+    } catch (error) {
+      caught = error;
+    }
+  }
+}
+
+new C();
+
+assert.notSameValue(caught, null);
+assert.sameValue(caught.constructor, TypeError);

test/language/expressions/in/private-field-rhs-unresolvable.js

@@ -0,0 +1,30 @@
+// Copyright 2021 the V8 project authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Algorithm interrupted by unresolvable reference
+info: |
+  1. Let privateIdentifier be the StringValue of PrivateIdentifier.
+  2. Let rref be the result of evaluating ShiftExpression.
+  3. Let rval be ? GetValue(rref).
+esid: sec-relational-operators-runtime-semantics-evaluation
+features: [class-fields-private, class-fields-private-in]
+---*/
+
+let caught = null;
+
+class C {
+  #field;
+  constructor() {
+    try {
+      #field in test262unresolvable;
+    } catch (error) {
+      caught = error;
+    }
+  }
+}
+
+new C();
+
+assert.notSameValue(caught, null);
+assert.sameValue(caught.constructor, ReferenceError);

test/language/expressions/in/private-field-rhs-yield-absent.js

@@ -0,0 +1,33 @@
+// Copyright 2021 the V8 project authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Parsing observes the `Yield` production parameter when present
+info: |
+  Syntax
+    RelationalExpression[In, Yield, Await]:
+    [...]
+    [+In]PrivateIdentifier in ShiftExpression[?Yield, ?Await]
+
+  [...]
+
+  1. Let privateIdentifier be the StringValue of PrivateIdentifier.
+  2. Let rref be the result of evaluating ShiftExpression.
+  3. Let rval be ? GetValue(rref).
+  4. If Type(rval) is not Object, throw a TypeError exception.
+esid: sec-relational-operators-runtime-semantics-evaluation
+negative:
+  phase: parse
+  type: SyntaxError
+features: [class-fields-private, class-fields-private-in]
+---*/
+
+$DONOTEVALUATE();
+
+class C {
+  #field;
+
+  static method() {
+    #field in yield;
+  }
+}

test/language/expressions/in/private-field-rhs-yield-present.js

@@ -0,0 +1,36 @@
+// Copyright 2021 the V8 project authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Parsing observes the `Yield` production parameter when present
+info: |
+  Syntax
+    RelationalExpression[In, Yield, Await]:
+    [...]
+    [+In]PrivateIdentifier in ShiftExpression[?Yield, ?Await]
+
+  [...]
+
+  1. Let privateIdentifier be the StringValue of PrivateIdentifier.
+  2. Let rref be the result of evaluating ShiftExpression.
+  3. Let rval be ? GetValue(rref).
+  4. If Type(rval) is not Object, throw a TypeError exception.
+esid: sec-relational-operators-runtime-semantics-evaluation
+features: [class-fields-private, class-fields-private-in]
+---*/
+
+class C {
+  #field;
+
+  static *isNameIn() {
+    return #field in (yield);
+  }
+}
+
+let iter1 = C.isNameIn();
+iter1.next();
+assert.sameValue(iter1.next(new C()).value, true);
+
+let iter2 = C.isNameIn();
+iter2.next();
+assert.sameValue(iter2.next({}).value, false);