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We incorrectly throw a syntax error when declaring a top level for-loop iteration variable the same as a parameter
https://bugs.webkit.org/show_bug.cgi?id=171041 <rdar://problem/32082516> Reviewed by Yusuke Suzuki. JSTests: * stress/lexical-scoping-for-loop.js: Added. (assert): (test1): (test2): (test3): (test4): (test5): (test6): (let.test7): (let.test8): (let.test9): (let.test10): (let.test11): (let.test12): Source/JavaScriptCore: We were treating a for-loop variable declaration potentially as a top level statement, e.g, in a program like this: ``` function foo() { for (let variable of expr) { } } ``` But we should not be. This had the consequence of making this type of program throw a syntax error: ``` function foo(arg) { for (let arg of expr) { } } ``` even though it should not. The fix is simple, we just need to increment the statement depth before parsing anything inside the for loop. * parser/Parser.cpp: (JSC::Parser<LexerType>::parseForStatement): LayoutTests: * js/parser-syntax-check-expected.txt: * js/script-tests/parser-syntax-check.js: Canonical link: https://commits.webkit.org/189327@main git-svn-id: https://svn.webkit.org/repository/webkit/trunk@217200 268f45cc-cd09-0410-ab3c-d52691b4dbfc
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‎JSTests/ChangeLog

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2017-05-21 Saam Barati <[email protected]>
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We incorrectly throw a syntax error when declaring a top level for-loop iteration variable the same as a parameter
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https://bugs.webkit.org/show_bug.cgi?id=171041
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<rdar://problem/32082516>
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Reviewed by Yusuke Suzuki.
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* stress/lexical-scoping-for-loop.js: Added.
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(assert):
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(test1):
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(test2):
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(test3):
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(test4):
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(test5):
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(test6):
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(let.test7):
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(let.test8):
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(let.test9):
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(let.test10):
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(let.test11):
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(let.test12):
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2017-05-19 Yusuke Suzuki <[email protected]>
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[JSC] Make get_by_val & string "499" to number 499

‎JSTests/stress/lexical-scoping-for-loop.js

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@@ -0,0 +1,61 @@
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'use strict';
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function assert(b) {
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if (!b)
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throw new Error("Bad");
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}
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function test1(x) {
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for (let x = 20; x < 30; ++x) { }
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return x;
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}
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function test2(x) {
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for (let x of [1,2,3]) { }
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return x;
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}
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function test3(x) {
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for (let x in {}) { }
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return x;
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}
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function test4(x) {
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let i = 0;
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for (const x = 20; i < 1; ++i) { }
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return x;
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}
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function test5(x) {
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for (const x of [1, 2, 3]) { }
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return x;
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}
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function test6(x) {
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for (const x in {}) { }
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return x;
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}
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let test7 = (x) => {
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for (let x = 20; x < 30; ++x) { }
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return x;
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}
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let test8 = (x) => {
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for (let x of [1,2,3]) { }
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return x;
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}
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let test9 = (x) => {
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for (let x in {}) { }
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return x;
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}
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let test10 = (x) => {
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let i = 0;
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for (const x = 20; i < 1; ++i) { }
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return x;
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}
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let test11 = (x) => {
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for (const x of [1, 2, 3]) { }
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return x;
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}
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let test12 = (x) => {
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for (const x in {}) { }
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return x;
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}
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for (let test of [test1, test2, test3, test4, test5, test7, test8, test9, test10, test11, test12])
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assert(test("foo") === "foo");

‎LayoutTests/ChangeLog

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2017-05-21 Saam Barati <[email protected]>
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We incorrectly throw a syntax error when declaring a top level for-loop iteration variable the same as a parameter
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https://bugs.webkit.org/show_bug.cgi?id=171041
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<rdar://problem/32082516>
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Reviewed by Yusuke Suzuki.
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* js/parser-syntax-check-expected.txt:
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* js/script-tests/parser-syntax-check.js:
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2017-05-21 Antti Koivisto <[email protected]>
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matchMedia('print').addListener() fires in WK1 but never in WK2 when printing (breaks printing Google maps, QuickLooks)

‎LayoutTests/js/parser-syntax-check-expected.txt

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@@ -556,6 +556,54 @@ PASS Invalid: "for (const {i} = 20 in b) { }". Produced the following syntax err
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PASS Invalid: "function f() { for (const {i} = 20 in b) { } }". Produced the following syntax error: "SyntaxError: Cannot assign to the loop variable inside a for-in loop header."
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PASS Invalid: "for (let {i} = 20 in b) { }". Produced the following syntax error: "SyntaxError: Cannot assign to the loop variable inside a for-in loop header."
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PASS Invalid: "function f() { for (let {i} = 20 in b) { } }". Produced the following syntax error: "SyntaxError: Cannot assign to the loop variable inside a for-in loop header."
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PASS Valid: "function x(i) { for (let i in {}) { } }"
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PASS Valid: "function f() { function x(i) { for (let i in {}) { } } }"
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PASS Valid: "function x(i) { for (let i of []) { } }"
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PASS Valid: "function f() { function x(i) { for (let i of []) { } } }"
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PASS Valid: "function x(i) { for (let i of []) { } }"
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PASS Valid: "function f() { function x(i) { for (let i of []) { } } }"
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PASS Valid: "function x(i) { for (let i; false; ) { } }"
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PASS Valid: "function f() { function x(i) { for (let i; false; ) { } } }"
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PASS Valid: "let f = (i) => { for (let i in {}) { } }"
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PASS Valid: "function f() { let f = (i) => { for (let i in {}) { } } }"
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PASS Valid: "let f = (i) => { for (let i of []) { } }"
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PASS Valid: "function f() { let f = (i) => { for (let i of []) { } } }"
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PASS Valid: "let f = (i) => { for (let i of []) { } }"
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PASS Valid: "function f() { let f = (i) => { for (let i of []) { } } }"
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PASS Valid: "let f = (i) => { for (let i; false; ) { } }"
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PASS Valid: "function f() { let f = (i) => { for (let i; false; ) { } } }"
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PASS Valid: "function* x(i) { for (let i in {}) { } }"
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PASS Valid: "function f() { function* x(i) { for (let i in {}) { } } }"
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PASS Valid: "function* x(i) { for (let i of []) { } }"
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PASS Valid: "function f() { function* x(i) { for (let i of []) { } } }"
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PASS Valid: "function* x(i) { for (let i of []) { } }"
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PASS Valid: "function f() { function* x(i) { for (let i of []) { } } }"
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PASS Valid: "function* x(i) { for (let i; false; ) { } }"
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PASS Valid: "function f() { function* x(i) { for (let i; false; ) { } } }"
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PASS Valid: "function x(i) { for (const i in {}) { } }"
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PASS Valid: "function f() { function x(i) { for (const i in {}) { } } }"
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PASS Valid: "function x(i) { for (const i of []) { } }"
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PASS Valid: "function f() { function x(i) { for (const i of []) { } } }"
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PASS Valid: "function x(i) { for (const i of []) { } }"
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PASS Valid: "function f() { function x(i) { for (const i of []) { } } }"
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PASS Valid: "function x(i) { for (const i = 20; false; ) { } }"
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PASS Valid: "function f() { function x(i) { for (const i = 20; false; ) { } } }"
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PASS Valid: "let f = (i) => { for (const i in {}) { } }"
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PASS Valid: "function f() { let f = (i) => { for (const i in {}) { } } }"
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PASS Valid: "let f = (i) => { for (const i of []) { } }"
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PASS Valid: "function f() { let f = (i) => { for (const i of []) { } } }"
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PASS Valid: "let f = (i) => { for (const i of []) { } }"
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PASS Valid: "function f() { let f = (i) => { for (const i of []) { } } }"
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PASS Valid: "let f = (i) => { for (const i = 20; false; ) { } }"
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PASS Valid: "function f() { let f = (i) => { for (const i = 20; false; ) { } } }"
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PASS Valid: "function* x(i) { for (const i in {}) { } }"
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PASS Valid: "function f() { function* x(i) { for (const i in {}) { } } }"
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PASS Valid: "function* x(i) { for (const i of []) { } }"
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PASS Valid: "function f() { function* x(i) { for (const i of []) { } } }"
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PASS Valid: "function* x(i) { for (const i of []) { } }"
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PASS Valid: "function f() { function* x(i) { for (const i of []) { } } }"
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PASS Valid: "function* x(i) { for (const i = 20; false; ) { } }"
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PASS Valid: "function f() { function* x(i) { for (const i = 20; false; ) { } } }"
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try statement
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PASS Invalid: "try { break } catch(e) {}". Produced the following syntax error: "SyntaxError: 'break' is only valid inside a switch or loop statement."
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PASS Invalid: "function f() { try { break } catch(e) {} }". Produced the following syntax error: "SyntaxError: 'break' is only valid inside a switch or loop statement."

‎LayoutTests/js/script-tests/parser-syntax-check.js

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@@ -371,6 +371,30 @@ invalid("for (let i = 20 in b) { }");
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invalid("for (const i = 20 in b) { }");
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invalid("for (const {i} = 20 in b) { }");
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invalid("for (let {i} = 20 in b) { }");
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valid("function x(i) { for (let i in {}) { } }");
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valid("function x(i) { for (let i of []) { } }");
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valid("function x(i) { for (let i of []) { } }");
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valid("function x(i) { for (let i; false; ) { } }");
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valid("let f = (i) => { for (let i in {}) { } }");
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valid("let f = (i) => { for (let i of []) { } }");
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valid("let f = (i) => { for (let i of []) { } }");
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valid("let f = (i) => { for (let i; false; ) { } }");
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valid("function* x(i) { for (let i in {}) { } }");
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valid("function* x(i) { for (let i of []) { } }");
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valid("function* x(i) { for (let i of []) { } }");
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valid("function* x(i) { for (let i; false; ) { } }");
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valid("function x(i) { for (const i in {}) { } }");
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valid("function x(i) { for (const i of []) { } }");
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valid("function x(i) { for (const i of []) { } }");
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valid("function x(i) { for (const i = 20; false; ) { } }");
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valid("let f = (i) => { for (const i in {}) { } }");
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valid("let f = (i) => { for (const i of []) { } }");
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valid("let f = (i) => { for (const i of []) { } }");
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valid("let f = (i) => { for (const i = 20; false; ) { } }");
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valid("function* x(i) { for (const i in {}) { } }");
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valid("function* x(i) { for (const i of []) { } }");
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valid("function* x(i) { for (const i of []) { } }");
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valid("function* x(i) { for (const i = 20; false; ) { } }");
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debug ("try statement");
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‎Source/JavaScriptCore/ChangeLog

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2017-05-21 Saam Barati <[email protected]>
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We incorrectly throw a syntax error when declaring a top level for-loop iteration variable the same as a parameter
4+
https://bugs.webkit.org/show_bug.cgi?id=171041
5+
<rdar://problem/32082516>
6+
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Reviewed by Yusuke Suzuki.
8+
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We were treating a for-loop variable declaration potentially as a top
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level statement, e.g, in a program like this:
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```
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function foo() {
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for (let variable of expr) { }
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}
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```
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But we should not be. This had the consequence of making this type of program
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throw a syntax error:
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```
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function foo(arg) {
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for (let arg of expr) { }
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}
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```
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even though it should not. The fix is simple, we just need to increment the
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statement depth before parsing anything inside the for loop.
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* parser/Parser.cpp:
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(JSC::Parser<LexerType>::parseForStatement):
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2017-05-19 Yusuke Suzuki <[email protected]>
230

331
[JSC] Make get_by_val & string "499" to number 499

‎Source/JavaScriptCore/parser/Parser.cpp

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@@ -1133,6 +1133,10 @@ template <class TreeBuilder> TreeStatement Parser<LexerType>::parseForStatement(
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JSTokenLocation location(tokenLocation());
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int startLine = tokenLine();
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next();
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DepthManager statementDepth(&m_statementDepth);
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m_statementDepth++;
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handleProductionOrFail(OPENPAREN, "(", "start", "for-loop header");
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int nonLHSCount = m_parserState.nonLHSCount;
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int declarations = 0;

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