Adapt existing tests regarding Symbols as weak values

WeakMap, WeakSet, WeakRef, and FinalizationRegistry all had tests
verifying what would happen if they were called with a value that wasn't
allowed as a weak value: before this proposal, that was a non-Object.
Now, allowed weak values are Objects, well-known Symbols, and unregistered
Symbols. That leaves registered Symbols that are still not allowed as weak
values.

This commit updates those tests to use a registered Symbol instead of an
unregistered Symbol; they should still pass, regardless of whether the
implementation has implemented symbols-as-weakmap-keys yet.

The tests are renamed as appropriate.

Also updates the frontmatter to the most current spec text, including the
CanBeHeldWeakly abstract operation.

See: tc39#2850

test/built-ins/FinalizationRegistry/prototype/register/target-not-object-throws.js → test/built-ins/FinalizationRegistry/prototype/register/throws-when-target-cannot-be-held-weakly.js

@@ -3,18 +3,10 @@
 
 /*---
 esid: sec-finalization-registry.prototype.register
-description: Throws a TypeError if target is not an Object
+description: Throws a TypeError if target cannot be held weakly
 info: |
-  FinalizationRegistry.prototype.register ( target , holdings [, unregisterToken ] )
-
-  1. Let finalizationRegistry be the this value.
-  2. If Type(finalizationRegistry) is not Object, throw a TypeError exception.
-  3. If Type(target) is not Object, throw a TypeError exception.
-  4. If finalizationRegistry does not have a [[Cells]] internal slot, throw a TypeError exception.
-  5. If Type(unregisterToken) is not Object,
-    a. If unregisterToken is not undefined, throw a TypeError exception.
-    b. Set unregisterToken to empty.
-  ...
+  FinalizationRegistry.prototype.register ( _target_ , _holdings_ [, _unregisterToken_ ] )
+  3. If CanBeHeldWeakly(_target_) is *false*, throw a *TypeError* exception.
 features: [FinalizationRegistry]
 ---*/
 
@@ -46,7 +38,7 @@ assert.throws(TypeError, function() {
   finalizationRegistry.register('object');
 }, 'string');
 
-var s = Symbol();
+var s = Symbol.for('registered symbol');
 assert.throws(TypeError, function() {
   finalizationRegistry.register(s);
-}, 'symbol');
+}, 'registered symbol');

test/built-ins/FinalizationRegistry/prototype/register/unregisterToken-not-object-or-undefined-throws.js → test/built-ins/FinalizationRegistry/prototype/register/throws-when-unregisterToken-not-undefined-and-cannot-be-held-weakly.js

@@ -3,17 +3,13 @@
 
 /*---
 esid: sec-finalization-registry.prototype.register
-description: Throws a TypeError if unregisterToken is not an Object or undefined
+description: >
+  Throws a TypeError if unregisterToken is not undefined and cannot be held
+  weakly
 info: |
-  FinalizationRegistry.prototype.register ( target , holdings [, unregisterToken ] )
-
-  1. Let finalizationRegistry be the this value.
-  2. If Type(finalizationRegistry) is not Object, throw a TypeError exception.
-  3. If Type(target) is not Object, throw a TypeError exception.
-  4. If finalizationRegistry does not have a [[Cells]] internal slot, throw a TypeError exception.
-  5. If Type(unregisterToken) is not Object,
-    a. If unregisterToken is not undefined, throw a TypeError exception.
-  ...
+  FinalizationRegistry.prototype.register ( _target_ , _holdings_ [, _unregisterToken_ ] )
+  5. If CanBeHeldWeakly(_unregisterToken_) is *false*, then
+    a. If _unregisterToken_ is not *undefined*, throw a *TypeError* exception.
 features: [FinalizationRegistry]
 ---*/
 
@@ -42,7 +38,7 @@ assert.throws(TypeError, function() {
   finalizationRegistry.register(target, undefined, 'object');
 }, 'string');
 
-var s = Symbol();
+var s = Symbol.for('registered symbol');
 assert.throws(TypeError, function() {
   finalizationRegistry.register(target, undefined, s);
-}, 'symbol');
+}, 'registered symbol');

test/built-ins/FinalizationRegistry/prototype/unregister/unregisterToken-not-object-throws.js → test/built-ins/FinalizationRegistry/prototype/unregister/throws-when-unregisterToken-cannot-be-held-weakly.js

@@ -3,15 +3,10 @@
 
 /*---
 esid: sec-finalization-registry.prototype.unregister
-description: Throws a TypeError if unregisterToken is not an Object
+description: Throws a TypeError if unregisterToken cannot be held weakly
 info: |
-  FinalizationRegistry.prototype.unregister ( unregisterToken )
-
-  1. Let finalizationRegistry be the this value.
-  2. If Type(finalizationRegistry) is not Object, throw a TypeError exception.
-  3. If finalizationRegistry does not have a [[Cells]] internal slot, throw a TypeError exception.
-  4. If Type(unregisterToken) is not Object, throw a TypeError exception.
-  ...
+  FinalizationRegistry.prototype.unregister ( _unregisterToken_ )
+  3. If CanBeHeldWeakly(_unregisterToken_) is *false*, throw a *TypeError* exception.
 features: [FinalizationRegistry]
 ---*/
 
@@ -43,7 +38,7 @@ assert.throws(TypeError, function() {
   finalizationRegistry.unregister('object');
 }, 'string');
 
-var s = Symbol();
+var s = Symbol.for('registered symbol');
 assert.throws(TypeError, function() {
   finalizationRegistry.unregister(s);
-}, 'symbol');
+}, 'registered symbol');

test/built-ins/WeakMap/iterator-items-are-not-object.js → test/built-ins/WeakMap/iterator-items-keys-cannot-be-held-weakly.js

@@ -3,19 +3,19 @@
 /*---
 esid: sec-weakmap-iterable
 description: >
-  Throws a TypeError if iterable itens are not Objects.
+  Throws a TypeError if keys in iterable items cannot be held weakly.
 info: |
-  WeakMap ( [ iterable ] )
-
-  ...
-  9. Repeat
-    ...
-    d. Let nextItem be IteratorValue(next).
-    e. ReturnIfAbrupt(nextItem).
-    f. If Type(nextItem) is not Object,
-      i. Let error be Completion{[[type]]: throw, [[value]]: a newly created
-      TypeError object, [[target]]:empty}.
-      ii. Return IteratorClose(iter, error).
+  WeakMap ( [ _iterable_ ] )
+  5. Let _adder_ be ? Get(_map_, *"set"*).
+  6. Return ? AddEntriesFromIterable(_map_, _iterable_, _adder_).
+
+  AddEntriesFromIterable:
+  3. Repeat,
+    i. Let _status_ be Completion(Call(_adder_, _target_, « _k_, _v_ »)).
+    j. IfAbruptCloseIterator(_status_, _iteratorRecord_).
+
+  WeakMap.prototype.set( _key_, _value_ ):
+  4. If CanBeHeldWeakly(_key_) is *false*, throw a *TypeError* exception.
 features: [Symbol, WeakMap]
 ---*/
 
@@ -36,8 +36,8 @@ assert.throws(TypeError, function() {
 });
 
 assert.throws(TypeError, function() {
-  new WeakMap([Symbol('a'), 1]);
-});
+  new WeakMap([Symbol.for('registered symbol'), 1]);
+}, 'Registered symbol not allowed as a WeakMap key');
 
 assert.throws(TypeError, function() {
   new WeakMap([undefined, 1]);

test/built-ins/WeakMap/prototype/delete/returns-false-value-is-not-object.js → test/built-ins/WeakMap/prototype/delete/returns-false-if-key-cannot-be-held-weakly.js

@@ -3,11 +3,10 @@
 /*---
 esid: sec-weakmap.prototype.delete
 description: >
-  Return false if value is not an Object.
+  Return false if the key cannot be held weakly.
 info: |
-  WeakMap.prototype.delete ( value )
-
-  5. If Type(key) is not Object, return false.
+  WeakMap.prototype.delete ( _key_ )
+  5. If CanBeHeldWeakly(_key_) is *false*, return *false*.
 features: [Symbol, WeakMap]
 ---*/
 
@@ -19,4 +18,4 @@ assert.sameValue(map.delete(NaN), false);
 assert.sameValue(map.delete(null), false);
 assert.sameValue(map.delete(undefined), false);
 assert.sameValue(map.delete(true), false);
-assert.sameValue(map.delete(Symbol()), false);
+assert.sameValue(map.delete(Symbol.for('registered symbol')), false, 'registered symbol');

test/built-ins/WeakMap/prototype/get/returns-undefined-key-is-not-object.js → test/built-ins/WeakMap/prototype/get/returns-undefined-if-key-cannot-be-held-weakly.js

@@ -3,15 +3,10 @@
 /*---
 esid: sec-weakmap.prototype.get
 description: >
-  Returns undefined when key is not an Object.
+  Returns undefined when key cannot be held weakly.
 info: |
-  WeakMap.prototype.get ( key )
-
-  ...
-  4. Let entries be the List that is the value of M’s [[WeakMapData]] internal
-  slot.
-  5. If Type(key) is not Object, return undefined.
-  ...
+  WeakMap.prototype.get ( _key_ )
+  4. If CanBeHeldWeakly(_key_) is *false*, return *undefined*.
 features: [Symbol, WeakMap]
 ---*/
 
@@ -37,6 +32,6 @@ assert.sameValue(
 );
 
 assert.sameValue(
-  map.get(Symbol()), undefined,
-  'Returns undefined if key is a Symbol'
+  map.get(Symbol.for('registered symbol')), undefined,
+  'Returns undefined if key is a registered Symbol'
 );

test/built-ins/WeakMap/prototype/has/returns-false-when-value-is-not-object.js → test/built-ins/WeakMap/prototype/has/returns-false-when-key-cannot-be-held-weakly.js

@@ -3,11 +3,10 @@
 /*---
 esid: sec-weakmap.prototype.has
 description: >
-  Returns false if value is not an Object.
+  Returns false if the key cannot be held weakly
 info: |
-  WeakMap.prototype.has ( value )
-
-  5. If Type(key) is not Object, return false.
+  WeakMap.prototype.has ( _key_ )
+  4. If CanBeHeldWeakly(_key_) is *false*, return *false*.
 features: [Symbol, WeakMap]
 ---*/
 
@@ -18,4 +17,4 @@ assert.sameValue(map.has(''), false);
 assert.sameValue(map.has(null), false);
 assert.sameValue(map.has(undefined), false);
 assert.sameValue(map.has(true), false);
-assert.sameValue(map.has(Symbol()), false);
+assert.sameValue(map.has(Symbol.for('registered symbol')), false, 'Registered symbol not allowed as key');

test/built-ins/WeakMap/prototype/set/key-not-object-throw.js → test/built-ins/WeakMap/prototype/set/throw-if-key-cannot-be-held-weakly.js

@@ -2,11 +2,10 @@
 // This code is governed by the BSD license found in the LICENSE file.
 /*---
 esid: sec-weakmap.prototype.set
-description: Throws TypeError if `key` is not Object.
+description: Throws TypeError if key cannot be held weakly.
 info: |
-  WeakMap.prototype.set ( key, value )
-
-  5. If Type(key) is not Object, throw a TypeError exception.
+  WeakMap.prototype.set ( _key_, _value_ )
+  4. If CanBeHeldWeakly(_key_) is *false*, throw a *TypeError* exception.
 features: [Symbol, WeakMap]
 ---*/
 
@@ -33,5 +32,5 @@ assert.throws(TypeError, function() {
 });
 
 assert.throws(TypeError, function() {
-  s.set(Symbol(), 1);
-});
+  s.set(Symbol.for('registered symbol'), 1);
+}, 'Registered symbol not allowed as WeakMap key');

test/built-ins/WeakRef/target-not-object-throws.js → test/built-ins/WeakRef/throws-when-target-cannot-be-held-weakly.js

@@ -4,13 +4,10 @@
 /*---
 esid: sec-weak-ref-target
 description: >
-  Throws a TypeError if target is not Object
+  Throws a TypeError if target cannot be held weakly
 info: |
-  WeakRef ( target )
-
-  1. If NewTarget is undefined, throw a TypeError exception.
-  2. If Type(target) is not Object, throw a TypeError exception.
-  ...
+  WeakRef ( _target_ )
+  2. If CanBeHeldWeakly(_target_) is *false*, throw a *TypeError* exception.
 features: [WeakRef]
 ---*/
 
@@ -39,10 +36,10 @@ assert.throws(TypeError, function() {
   new WeakRef('Object');
 }, 'string');
 
-var s = Symbol();
+var s = Symbol.for('registered symbol');
 assert.throws(TypeError, function() {
   new WeakRef(s);
-}, 'symbol');
+}, 'registered symbol');
 
 assert.throws(TypeError, function() {
   new WeakRef(true);

test/built-ins/WeakSet/prototype/add/value-not-object-throw.js → test/built-ins/WeakSet/prototype/add/throw-when-value-cannot-be-held-weakly.js

@@ -2,11 +2,10 @@
 // This code is governed by the BSD license found in the LICENSE file.
 /*---
 esid: sec-weakset.prototype.add
-description: Throws TypeError if `value` is not Object.
+description: Throws TypeError if value cannot be held weakly.
 info: |
-  WeakSet.prototype.add ( value )
-
-  4. If Type(value) is not Object, throw a TypeError exception.
+  WeakSet.prototype.add ( _value_ )
+  3. If CanBeHeldWeakly(_value_) is *false*, throw a *TypeError* exception.
 features: [Symbol, WeakSet]
 ---*/
 
@@ -33,5 +32,5 @@ assert.throws(TypeError, function() {
 });
 
 assert.throws(TypeError, function() {
-  s.add(Symbol());
-});
+  s.add(Symbol.for('registered symbol'));
+}, 'Registered symbol not allowed as WeakSet value');

test/built-ins/WeakSet/prototype/delete/returns-false-value-is-not-object.js → test/built-ins/WeakSet/prototype/delete/returns-false-when-value-cannot-be-held-weakly.js

@@ -3,11 +3,10 @@
 /*---
 esid: sec-weakset.prototype.delete
 description: >
-  Return false if value is not a non-null Object.
+  Return false if value cannot be held weakly.
 info: |
-  WeakSet.prototype.delete ( value )
-
-  4. If Type(value) is not Object, return false.
+  WeakSet.prototype.delete ( _value_ )
+  3. If CanBeHeldWeakly(_value_) is *false*, return *false*.
 features: [Symbol, WeakSet]
 ---*/
 
@@ -18,4 +17,4 @@ assert.sameValue(s.delete(''), false);
 assert.sameValue(s.delete(null), false);
 assert.sameValue(s.delete(undefined), false);
 assert.sameValue(s.delete(true), false);
-assert.sameValue(s.delete(Symbol()), false);
+assert.sameValue(s.delete(Symbol.for('registered symbol')), false, 'Registered symbol not allowed as value');

test/built-ins/WeakSet/prototype/has/returns-false-when-value-is-not-object.js → test/built-ins/WeakSet/prototype/has/returns-false-when-value-cannot-be-held-weakly.js

@@ -3,11 +3,10 @@
 /*---
 esid: sec-weakset.prototype.has
 description: >
-  Returns false if value is not a non-null Object.
+  Returns false if value cannot be held weakly.
 info: |
-  WeakSet.prototype.has ( value )
-
-  5. If Type(value) is not Object, return false.
+  WeakSet.prototype.has ( _value_ )
+  4. If CanBeHeldWeakly(_value_) is *false*, return *false*.
 features: [Symbol, WeakSet]
 ---*/
 
@@ -18,4 +17,4 @@ assert.sameValue(s.has(''), false);
 assert.sameValue(s.has(null), false);
 assert.sameValue(s.has(undefined), false);
 assert.sameValue(s.has(true), false);
-assert.sameValue(s.has(Symbol()), false);
+assert.sameValue(s.has(Symbol.for('registered symbol')), false, 'Registered symbol not allowed as value');