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// Test scope lookups are executed in the correct order.
function createScope() {
let log = [];
let environment = {};
let scope = new Proxy(environment, new Proxy({
has(target, property) {
log.push({target, property});
return Reflect.has(target, property);
},
get(target, property, receiver) {
log.push({target, property, receiver});
return Reflect.get(target, property, receiver);
},
set(target, property, value, receiver) {
log.push({target, property, value, receiver});
return Reflect.set(target, property, value, receiver);
},
getOwnPropertyDescriptor(target, property) {
log.push({target, property});
return Reflect.getOwnPropertyDescriptor(target, property);
},
defineProperty(target, property, descriptor) {
log.push({target, property, descriptor});
return Reflect.defineProperty(target, property, descriptor);
},
}, {
get(target, property, receiver) {
log.push(property);
return Reflect.get(target, property, receiver);
}
}));
return {log, environment, scope};
}
// AndAssignExpr
{
let {log, environment, scope} = createScope();
environment.a = true;
with (scope) {
a &&= false;
}
assertEq(environment.a, false);
with (scope) {
a &&= true;
}
assertEq(environment.a, false);
assertDeepEq(log, [
// Execution Contexts, 8.3.2 ResolveBinding ( name [ , env ] )
// Lexical Environments, 8.1.2.1 GetIdentifierReference ( lex, name, strict )
// Object Environment Records, 8.1.1.2.1 HasBinding ( N )
"has", {target: environment, property: "a"},
"get", {target: environment, property: Symbol.unscopables, receiver: scope},
// Reference Type, 6.2.4.8 GetValue ( V )
// Object Environment Records, 8.1.1.2.6 GetBindingValue ( N, S )
"has", {target: environment, property: "a"},
"get", {target: environment, property: "a", receiver: scope},
// Reference Type, 6.2.4.9 PutValue ( V, W )
// Object Environment Records, 8.1.1.2.5 SetMutableBinding ( N, V, S )
"set", {target: environment, property: "a", value: false, receiver: scope},
// Ordinary Objects, 9.1.9 [[Set]] ( P, V, Receiver )
// Ordinary Objects, 9.1.9.1 OrdinarySet ( O, P, V, Receiver )
// Ordinary Objects, 9.1.9.2 OrdinarySetWithOwnDescriptor ( O, P, V, Receiver, ownDesc )
"getOwnPropertyDescriptor", {target: environment, property: "a"},
"defineProperty", {target: environment, property: "a", descriptor: {value: false}},
// Execution Contexts, 8.3.2 ResolveBinding ( name [ , env ] )
// Lexical Environments, 8.1.2.1 GetIdentifierReference ( lex, name, strict )
// Object Environment Records, 8.1.1.2.1 HasBinding ( N )
"has", {target: environment, property: "a"},
"get", {target: environment, property: Symbol.unscopables, receiver: scope},
// Reference Type, 6.2.4.8 GetValue ( V )
// Object Environment Records, 8.1.1.2.6 GetBindingValue ( N, S )
"has", {target: environment, property: "a"},
"get", {target: environment, property: "a", receiver: scope},
]);
}
// OrAssignExpr
{
let {log, environment, scope} = createScope();
environment.a = false;
with (scope) {
a ||= true;
}
assertEq(environment.a, true);
with (scope) {
a ||= false;
}
assertEq(environment.a, true);
assertDeepEq(log, [
// Execution Contexts, 8.3.2 ResolveBinding ( name [ , env ] )
// Lexical Environments, 8.1.2.1 GetIdentifierReference ( lex, name, strict )
// Object Environment Records, 8.1.1.2.1 HasBinding ( N )
"has", {target: environment, property: "a"},
"get", {target: environment, property: Symbol.unscopables, receiver: scope},
// Reference Type, 6.2.4.8 GetValue ( V )
// Object Environment Records, 8.1.1.2.6 GetBindingValue ( N, S )
"has", {target: environment, property: "a"},
"get", {target: environment, property: "a", receiver: scope},
// Reference Type, 6.2.4.9 PutValue ( V, W )
// Object Environment Records, 8.1.1.2.5 SetMutableBinding ( N, V, S )
"set", {target: environment, property: "a", value: true, receiver: scope},
// Ordinary Objects, 9.1.9 [[Set]] ( P, V, Receiver )
// Ordinary Objects, 9.1.9.1 OrdinarySet ( O, P, V, Receiver )
// Ordinary Objects, 9.1.9.2 OrdinarySetWithOwnDescriptor ( O, P, V, Receiver, ownDesc )
"getOwnPropertyDescriptor", {target: environment, property: "a"},
"defineProperty", {target: environment, property: "a", descriptor: {value: true}},
// Execution Contexts, 8.3.2 ResolveBinding ( name [ , env ] )
// Lexical Environments, 8.1.2.1 GetIdentifierReference ( lex, name, strict )
// Object Environment Records, 8.1.1.2.1 HasBinding ( N )
"has", {target: environment, property: "a"},
"get", {target: environment, property: Symbol.unscopables, receiver: scope},
// Reference Type, 6.2.4.8 GetValue ( V )
// Object Environment Records, 8.1.1.2.6 GetBindingValue ( N, S )
"has", {target: environment, property: "a"},
"get", {target: environment, property: "a", receiver: scope},
]);
}
// CoalesceAssignExpr
{
let {log, environment, scope} = createScope();
environment.a = null;
with (scope) {
a ??= true;
}
assertEq(environment.a, true);
with (scope) {
a ??= false;
}
assertEq(environment.a, true);
assertDeepEq(log, [
// Execution Contexts, 8.3.2 ResolveBinding ( name [ , env ] )
// Lexical Environments, 8.1.2.1 GetIdentifierReference ( lex, name, strict )
// Object Environment Records, 8.1.1.2.1 HasBinding ( N )
"has", {target: environment, property: "a"},
"get", {target: environment, property: Symbol.unscopables, receiver: scope},
// Reference Type, 6.2.4.8 GetValue ( V )
// Object Environment Records, 8.1.1.2.6 GetBindingValue ( N, S )
"has", {target: environment, property: "a"},
"get", {target: environment, property: "a", receiver: scope},
// Reference Type, 6.2.4.9 PutValue ( V, W )
// Object Environment Records, 8.1.1.2.5 SetMutableBinding ( N, V, S )
"set", {target: environment, property: "a", value: true, receiver: scope},
// Ordinary Objects, 9.1.9 [[Set]] ( P, V, Receiver )
// Ordinary Objects, 9.1.9.1 OrdinarySet ( O, P, V, Receiver )
// Ordinary Objects, 9.1.9.2 OrdinarySetWithOwnDescriptor ( O, P, V, Receiver, ownDesc )
"getOwnPropertyDescriptor", {target: environment, property: "a"},
"defineProperty", {target: environment, property: "a", descriptor: {value: true}},
// Execution Contexts, 8.3.2 ResolveBinding ( name [ , env ] )
// Lexical Environments, 8.1.2.1 GetIdentifierReference ( lex, name, strict )
// Object Environment Records, 8.1.1.2.1 HasBinding ( N )
"has", {target: environment, property: "a"},
"get", {target: environment, property: Symbol.unscopables, receiver: scope},
// Reference Type, 6.2.4.8 GetValue ( V )
// Object Environment Records, 8.1.1.2.6 GetBindingValue ( N, S )
"has", {target: environment, property: "a"},
"get", {target: environment, property: "a", receiver: scope},
]);
}
if (typeof reportCompare === "function")
reportCompare(0, 0);