Source code
Revision control
Copy as Markdown
Other Tools
// This file was procedurally generated from the following sources:
// - src/class-elements/prod-private-method-initialize-order.case
// - src/class-elements/private-methods/cls-expr.template
/*---
description: Private methods are added before any field initializer is run, even if they appear textually later (private method definitions in a class expression)
esid: prod-MethodDefinition
features: [class-methods-private, class-fields-private, class-fields-public, class]
flags: [generated]
info: |
ClassElement :
MethodDefinition
...
;
ClassElementName :
PropertyName
PrivateName
PrivateName ::
# IdentifierName
MethodDefinition :
ClassElementName ( UniqueFormalParameters ) { FunctionBody }
GeneratorMethod
AsyncMethod
AsyncGeneratorMethod
get ClassElementName () { FunctionBody }
set ClassElementName ( PropertySetParameterList ) { FunctionBody }
GeneratorMethod :
* ClassElementName ( UniqueFormalParameters ){GeneratorBody}
AsyncMethod :
async [no LineTerminator here] ClassElementName ( UniqueFormalParameters ) { AsyncFunctionBody }
AsyncGeneratorMethod :
async [no LineTerminator here]* ClassElementName ( UniqueFormalParameters ) { AsyncGeneratorBody }
---
InitializeClassElements ( F, proto )
...
5. For each item element in order from elements,
a. Assert: If element.[[Placement]] is "prototype" or "static", then element.[[Key]] is not a Private Name.
b. If element.[[Kind]] is "method" and element.[[Placement]] is "static" or "prototype",
i. Let receiver be F if element.[[Placement]] is "static", else let receiver be proto.
ii. Perform ? DefineClassElement(receiver, element).
InitializeInstanceElements ( O, constructor )
...
3. Let elements be the value of F's [[Elements]] internal slot.
4. For each item element in order from elements,
a. If element.[[Placement]] is "own" and element.[[Kind]] is "method",
i. Perform ? DefineClassElement(O, element).
DefineClassElement (receiver, element)
...
6. If key is a Private Name,
a. Perform ? PrivateFieldDefine(receiver, key, descriptor).
PrivateFieldDefine (P, O, desc)
...
6. Append { [[PrivateName]]: P, [[PrivateFieldDescriptor]]: desc } to O.[[PrivateFieldDescriptors]].
InitializeInstanceElements ( O, constructor )
...
4. For each item element in order from elements,
a. If element.[[Placement]] is "own" and element.[[Kind]] is "method",
i. Perform ? DefineClassElement(O, element).
5. For each item element in order from elements,
a. If element.[[Placement]] is "own" and element.[[Kind]] is "field",
i. Assert: element.[[Descriptor]] does not have a [[Value]], [[Get]] or [[Set]] slot.
ii. Perform ? DefineClassElement(O, element).
6. Return.
EDITOR'S NOTE:
Value properties are added before initializers so that private methods are visible from all initializers.
---*/
/***
* template notes:
* 1. method should always be #m
* 2. the template provides c.ref/other.ref for external reference
*/
function hasProp(obj, name, expected, msg) {
var hasOwnProperty = Object.prototype.hasOwnProperty.call(obj, name);
assert.sameValue(hasOwnProperty, expected, msg);
var hasProperty = Reflect.has(obj, name);
assert.sameValue(hasProperty, expected, msg);
}
var C = class {
a = this.#m();
#m() { return 42; }
get bGetter() { return this.#b; }
#b = this.#m();
get ref() { return this.#m; }
constructor() {
hasProp(this, '#m', false, 'private methods are defined in an special internal slot and cannot be found as own properties');
assert.sameValue(typeof this.#m, 'function');
assert.sameValue(this.ref, this.#m, 'returns the same value');
assert.sameValue(this.#m, (() => this)().#m, 'memberexpression and call expression forms');
assert.sameValue(this.a, 42);
assert.sameValue(this.#b, 42);
}
}
var c = new C();
var other = new C();
hasProp(C.prototype, '#m', false, 'method is not defined in the prototype');
hasProp(C, '#m', false, 'method is not defined in the contructor');
hasProp(c, '#m', false, 'method cannot be seen outside of the class');
/***
* MethodDefinition : ClassElementName ( UniqueFormalParameters ) { FunctionBody }
*
* 1. Let methodDef be DefineMethod of MethodDefinition with argument homeObject.
* ...
*/
assert.sameValue(c.ref, other.ref, 'The method is defined once, and reused on every new instance');
assert.sameValue(c.a, 42);
assert.sameValue(c.bGetter, 42);
reportCompare(0, 0);