v8/test/mjsunit/es6/catch-parameter-redeclaration.js
bakkot 819fe04645 Reland of Add errors for declarations which conflict with catch parameters. (patchset #1 id:1 of https://codereview.chromium.org/2112223002/ )
Reason for revert:
Correcting issue.

Original issue's description:
> Revert of Add errors for declarations which conflict with catch parameters. (patchset #6 id:100001 of https://codereview.chromium.org/2109733003/ )
>
> Reason for revert:
> Fuzzer claims `try {  \"\" ; } catch(x) { let x1 = [1,,], x = x; }` causes a crash.
>
> Original issue's description:
> > Add errors for declarations which conflict with catch parameters.
> >
> > Catch parameters are largely treated as lexical declarations in the
> > block which contains their body for the purposes of early syntax errors,
> > with some exceptions outlined in B.3.5. This patch introduces most of
> > those errors, except those from `eval('for (var e of ...);')` inside of
> > a catch with a simple parameter named 'e'.
> >
> > Note that annex B.3.5 allows var declarations to conflict with simple
> > catch parameters, except when the variable declaration is the init of a
> > for-of statement.
> >
> > BUG=v8:5112,v8:4231
> >
> > Committed: https://crrev.com/2907c726b2bb5cf20b2bec639ca9e6a521585406
> > Cr-Commit-Position: refs/heads/master@{#37462}
>
> TBR=littledan@chromium.org
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=v8:5112,v8:4231
>
> Committed: https://crrev.com/8834d5ecb559001c87c42322969471da60574a8c
> Cr-Commit-Position: refs/heads/master@{#37464}

R=littledan@chromium.org
BUG=v8:5112,v8:4231

Review-Url: https://codereview.chromium.org/2119933002
Cr-Commit-Position: refs/heads/master@{#37728}
2016-07-13 19:29:11 +00:00

113 lines
2.1 KiB
JavaScript

// Copyright 2016 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
function checkIsRedeclarationError(code) {
try {
eval(`
checkIsRedeclarationError : {
break checkIsRedeclarationError;
${code}
}
`);
assertUnreachable();
} catch(e) {
assertInstanceof(e, SyntaxError );
assertTrue( e.toString().indexOf("has already been declared") >= 0 );
}
}
function checkIsNotRedeclarationError(code) {
assertDoesNotThrow(()=>eval(`
checkIsNotRedeclarationError_label : {
break checkIsNotRedeclarationError_label;
${code}
}
`));
}
let lexical_e = [
'let e',
'let f, g, e',
'let [f] = [], [] = [], e = e, h',
'let {e} = 0',
'let {f, e} = 0',
'let {f, g} = 0, {e} = 0',
'let {f = 0, e = 1} = 0',
'let [e] = 0',
'let [f, e] = 0',
'let {f:e} = 0',
'let [[[], e]] = 0',
'const e = 0',
'const f = 0, g = 0, e = 0',
'const {e} = 0',
'const [e] = 0',
'const {f:e} = 0',
'const [[[], e]] = 0',
'function e(){}',
'function* e(){}',
];
let not_lexical_e = [
'var e',
'var f, e',
'var {e} = 0',
'let {} = 0',
'let {e:f} = 0',
'{ function e(){} }'
];
// Check that lexical declarations cannot override a simple catch parameter
for (let declaration of lexical_e) {
checkIsRedeclarationError(`
try {
throw 0;
} catch(e) {
${declaration}
}
`);
}
// Check that lexical declarations cannot override a complex catch parameter
for (let declaration of lexical_e) {
checkIsRedeclarationError(`
try {
throw 0;
} catch({e}) {
${declaration}
}
`);
}
// Check that non-lexical declarations can override a simple catch parameter
for (let declaration of not_lexical_e) {
checkIsNotRedeclarationError(`
try {
throw 0;
} catch(e) {
${declaration}
}
`);
}
// Check that the above error does not occur if a declaration scope is between
// the catch and the loop.
for (let declaration of lexical_e) {
checkIsNotRedeclarationError(`
try {
throw 0;
} catch(e) {
(()=>{${declaration}})();
}
`);
checkIsNotRedeclarationError(`
try {
throw 0;
} catch(e) {
(function(){${declaration}})();
}
`);
}