From d1c146adf23e317facd03cd5c097f12a69947392 Mon Sep 17 00:00:00 2001 From: Gaming4JC Date: Mon, 10 Jun 2019 18:41:38 -0400 Subject: 1340148 - Disallow function redeclarations at module top level. --- js/src/frontend/NameAnalysisTypes.h | 2 + js/src/frontend/Parser.cpp | 28 +++++-- .../jit-test/modules/export-default-async-asi.js | 2 + .../tests/modules/function-redeclaration.js | 94 ++++++++++++++++++++++ 4 files changed, 121 insertions(+), 5 deletions(-) create mode 100644 js/src/jit-test/modules/export-default-async-asi.js create mode 100644 js/src/jit-test/tests/modules/function-redeclaration.js diff --git a/js/src/frontend/NameAnalysisTypes.h b/js/src/frontend/NameAnalysisTypes.h index b94ca6cc0..2d327c827 100644 --- a/js/src/frontend/NameAnalysisTypes.h +++ b/js/src/frontend/NameAnalysisTypes.h @@ -78,6 +78,7 @@ enum class DeclarationKind : uint8_t Const, Import, BodyLevelFunction, + ModuleBodyLevelFunction, LexicalFunction, VarForAnnexBLexicalFunction, SimpleCatchParameter, @@ -95,6 +96,7 @@ DeclarationKindToBindingKind(DeclarationKind kind) case DeclarationKind::Var: case DeclarationKind::BodyLevelFunction: + case DeclarationKind::ModuleBodyLevelFunction: case DeclarationKind::VarForAnnexBLexicalFunction: case DeclarationKind::ForOfVar: return BindingKind::Var; diff --git a/js/src/frontend/Parser.cpp b/js/src/frontend/Parser.cpp index c96e8c065..d62a26f76 100644 --- a/js/src/frontend/Parser.cpp +++ b/js/src/frontend/Parser.cpp @@ -119,6 +119,7 @@ DeclarationKindString(DeclarationKind kind) case DeclarationKind::Import: return "import"; case DeclarationKind::BodyLevelFunction: + case DeclarationKind::ModuleBodyLevelFunction: case DeclarationKind::LexicalFunction: return "function"; case DeclarationKind::VarForAnnexBLexicalFunction: @@ -1380,6 +1381,24 @@ Parser::noteDeclaredName(HandlePropertyName name, DeclarationKind break; } + case DeclarationKind::ModuleBodyLevelFunction: { + MOZ_ASSERT(pc->atModuleLevel()); + + AddDeclaredNamePtr p = pc->varScope().lookupDeclaredNameForAdd(name); + if (p) { + reportRedeclaration(name, p->value()->kind(), pos, p->value()->pos()); + return false; + } + + if (!pc->varScope().addDeclaredName(pc, p, name, kind, pos.begin)) + return false; + + // Body-level functions in modules are always closed over. + pc->varScope().lookupDeclaredName(name)->value()->setClosedOver(); + + break; + } + case DeclarationKind::FormalParameter: { // It is an early error if any non-positional formal parameter name // (e.g., destructuring formal parameter) is duplicated. @@ -3750,12 +3769,11 @@ Parser::functionStmt(uint32_t preludeStart, YieldHandling yieldHan if (!noteDeclaredName(name, DeclarationKind::LexicalFunction, pos())) return null(); } else { - if (!noteDeclaredName(name, DeclarationKind::BodyLevelFunction, pos())) + DeclarationKind kind = pc->atModuleLevel() + ? DeclarationKind::ModuleBodyLevelFunction + : DeclarationKind::BodyLevelFunction; + if (!noteDeclaredName(name, kind, pos())) return null(); - - // Body-level functions in modules are always closed over. - if (pc->atModuleLevel()) - pc->varScope().lookupDeclaredName(name)->value()->setClosedOver(); } Node pn = handler.newFunctionStatement(); diff --git a/js/src/jit-test/modules/export-default-async-asi.js b/js/src/jit-test/modules/export-default-async-asi.js new file mode 100644 index 000000000..a69a7aa3d --- /dev/null +++ b/js/src/jit-test/modules/export-default-async-asi.js @@ -0,0 +1,2 @@ +export default async // ASI occurs here due to the [no LineTerminator here] restriction on default-exporting an async function +function async() { return 17; } diff --git a/js/src/jit-test/tests/modules/function-redeclaration.js b/js/src/jit-test/tests/modules/function-redeclaration.js new file mode 100644 index 000000000..b84704641 --- /dev/null +++ b/js/src/jit-test/tests/modules/function-redeclaration.js @@ -0,0 +1,94 @@ +load(libdir + "asserts.js"); + +var functionDeclarations = [ + "function f(){}", + "function* f(){}", + "async function f(){}", +]; + +var varDeclarations = [ + "var f", + "{ var f; }", + "for (var f in null);", + "for (var f of null);", + "for (var f; ;);", +]; + +var lexicalDeclarations = [ + "let f;", + "const f = 0;", + "class f {};", +]; + +var imports = [ + "import f from '';", + "import f, {} from '';", + "import d, {f} from '';", + "import d, {f as f} from '';", + "import d, {foo as f} from '';", + "import f, * as d from '';", + "import d, * as f from '';", + "import {f} from '';", + "import {f as f} from '';", + "import {foo as f} from '';", + "import* as f from '';", +]; + +var exports = [ + "export var f;", + ...functionDeclarations.map(fn => `export ${fn};`), + ...lexicalDeclarations.map(ld => `export ${ld};`), + ...functionDeclarations.map(fn => `export default ${fn};`), + "export default class f {};", +]; + +var redeclarations = [ + ...functionDeclarations, + ...varDeclarations, + ...lexicalDeclarations, + ...imports, + ...exports, +]; + +var noredeclarations = [ + ...functionDeclarations.map(fn => `{ ${fn} }`), + ...lexicalDeclarations.map(ld => `{ ${ld} }`), + ...["let", "const"].map(ld => `for (${ld} f in null);`), + ...["let", "const"].map(ld => `for (${ld} f of null);`), + ...["let", "const"].map(ld => `for (${ld} f = 0; ;);`), + "export {f};", + "export {f as f};", + "export {foo as f}; var foo;", + "export {f} from '';", + "export {f as f} from '';", + "export {foo as f} from '';", +]; + +for (var decl of functionDeclarations) { + for (var redecl of redeclarations) { + assertThrowsInstanceOf(() => { + parseModule(` + ${decl} + ${redecl} + `); + }, SyntaxError); + + assertThrowsInstanceOf(() => { + parseModule(` + ${redecl} + ${decl} + `); + }, SyntaxError); + } + + for (var redecl of noredeclarations) { + parseModule(` + ${decl} + ${redecl} + `); + parseModule(` + ${redecl} + ${decl} + `); + } +} -- cgit v1.2.3