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weswighamweswigham
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Add command line flag to allow synthetic default exports
1 parent 4cba1b2 commit a32f44f

26 files changed

Lines changed: 424 additions & 1 deletion

‎src/compiler/checker.ts‎

Lines changed: 5 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -46,6 +46,7 @@ namespace ts {
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const compilerOptions = host.getCompilerOptions();
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const languageVersion = compilerOptions.target || ScriptTarget.ES3;
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const modulekind = compilerOptions.module ? compilerOptions.module : languageVersion === ScriptTarget.ES6 ? ModuleKind.ES6 : ModuleKind.None;
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const allowSyntheticDefaultImports = compilerOptions.hasOwnProperty("allowSyntheticDefaultImports") ? compilerOptions.allowSyntheticDefaultImports : modulekind === ModuleKind.System;
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const emitResolver = createResolver();
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@@ -730,9 +731,12 @@ namespace ts {
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const moduleSymbol = resolveExternalModuleName(node, (<ImportDeclaration>node.parent).moduleSpecifier);
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if (moduleSymbol) {
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const exportDefaultSymbol = resolveSymbol(moduleSymbol.exports["default"]);
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if (!exportDefaultSymbol) {
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if (!exportDefaultSymbol && !allowSyntheticDefaultImports) {
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error(node.name, Diagnostics.Module_0_has_no_default_export, symbolToString(moduleSymbol));
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}
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else if (!exportDefaultSymbol && allowSyntheticDefaultImports) {
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return resolveSymbol(moduleSymbol.exports["export="]) || resolveSymbol(moduleSymbol);
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}
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return exportDefaultSymbol;
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}
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}

‎src/compiler/commandLineParser.ts‎

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Original file line numberDiff line numberDiff line change
@@ -279,6 +279,11 @@ namespace ts {
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name: "forceConsistentCasingInFileNames",
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type: "boolean",
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description: Diagnostics.Disallow_inconsistently_cased_references_to_the_same_file
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},
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{
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name: "allowSyntheticDefaultImports",
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type: "boolean",
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description: Diagnostics.Allow_default_imports_from_modules_with_no_default_export
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}
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];
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‎src/compiler/diagnosticMessages.json‎

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Original file line numberDiff line numberDiff line change
@@ -2101,6 +2101,10 @@
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"category": "Message",
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"code": 6010
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},
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"Allow default imports from modules with no default export": {
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"category": "Message",
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"code": 6011
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},
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"Specify ECMAScript target version: 'ES3' (default), 'ES5', or 'ES2015' (experimental)": {
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"category": "Message",
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"code": 6015

‎src/compiler/types.ts‎

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -2109,6 +2109,7 @@ namespace ts {
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noImplicitReturns?: boolean;
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noFallthroughCasesInSwitch?: boolean;
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forceConsistentCasingInFileNames?: boolean;
2112+
allowSyntheticDefaultImports?: boolean;
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/* @internal */ stripInternal?: boolean;
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21142115
// Skip checking lib.d.ts to help speed up tests.

‎tests/baselines/reference/allowSyntheticDefaultImports1.js‎

Lines changed: 22 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,22 @@
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//// [tests/cases/compiler/allowSyntheticDefaultImports1.ts] ////
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//// [a.ts]
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import Namespace from "./b";
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export var x = new Namespace.Foo();
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//// [b.ts]
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export class Foo {
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member: string;
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}
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12+
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//// [b.js]
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var Foo = (function () {
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function Foo() {
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}
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return Foo;
18+
})();
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exports.Foo = Foo;
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//// [a.js]
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var b_1 = require("./b");
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exports.x = new b_1["default"].Foo();

‎tests/baselines/reference/allowSyntheticDefaultImports1.symbols‎

Lines changed: 18 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,18 @@
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=== tests/cases/compiler/a.ts ===
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import Namespace from "./b";
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>Namespace : Symbol(Namespace, Decl(a.ts, 0, 6))
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export var x = new Namespace.Foo();
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>x : Symbol(x, Decl(a.ts, 1, 10))
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>Namespace.Foo : Symbol(Namespace.Foo, Decl(b.ts, 0, 0))
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>Namespace : Symbol(Namespace, Decl(a.ts, 0, 6))
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>Foo : Symbol(Namespace.Foo, Decl(b.ts, 0, 0))
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=== tests/cases/compiler/b.ts ===
12+
export class Foo {
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>Foo : Symbol(Foo, Decl(b.ts, 0, 0))
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member: string;
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>member : Symbol(member, Decl(b.ts, 0, 18))
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}
18+

‎tests/baselines/reference/allowSyntheticDefaultImports1.types‎

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,19 @@
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=== tests/cases/compiler/a.ts ===
2+
import Namespace from "./b";
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>Namespace : typeof Namespace
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export var x = new Namespace.Foo();
6+
>x : Namespace.Foo
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>new Namespace.Foo() : Namespace.Foo
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>Namespace.Foo : typeof Namespace.Foo
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>Namespace : typeof Namespace
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>Foo : typeof Namespace.Foo
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12+
=== tests/cases/compiler/b.ts ===
13+
export class Foo {
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>Foo : Foo
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member: string;
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>member : string
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}
19+

‎tests/baselines/reference/allowSyntheticDefaultImports2.js‎

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,40 @@
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//// [tests/cases/compiler/allowSyntheticDefaultImports2.ts] ////
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//// [a.ts]
4+
import Namespace from "./b";
5+
export var x = new Namespace.Foo();
6+
7+
//// [b.ts]
8+
export class Foo {
9+
member: string;
10+
}
11+
12+
//// [b.js]
13+
System.register([], function(exports_1) {
14+
var Foo;
15+
return {
16+
setters:[],
17+
execute: function() {
18+
Foo = (function () {
19+
function Foo() {
20+
}
21+
return Foo;
22+
})();
23+
exports_1("Foo", Foo);
24+
}
25+
}
26+
});
27+
//// [a.js]
28+
System.register(["./b"], function(exports_1) {
29+
var b_1;
30+
var x;
31+
return {
32+
setters:[
33+
function (b_1_1) {
34+
b_1 = b_1_1;
35+
}],
36+
execute: function() {
37+
exports_1("x", x = new b_1["default"].Foo());
38+
}
39+
}
40+
});

‎tests/baselines/reference/allowSyntheticDefaultImports2.symbols‎

Lines changed: 17 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,17 @@
1+
=== tests/cases/compiler/a.ts ===
2+
import Namespace from "./b";
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>Namespace : Symbol(Namespace, Decl(a.ts, 0, 6))
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5+
export var x = new Namespace.Foo();
6+
>x : Symbol(x, Decl(a.ts, 1, 10))
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>Namespace.Foo : Symbol(Namespace.Foo, Decl(b.ts, 0, 0))
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>Namespace : Symbol(Namespace, Decl(a.ts, 0, 6))
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>Foo : Symbol(Namespace.Foo, Decl(b.ts, 0, 0))
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11+
=== tests/cases/compiler/b.ts ===
12+
export class Foo {
13+
>Foo : Symbol(Foo, Decl(b.ts, 0, 0))
14+
15+
member: string;
16+
>member : Symbol(member, Decl(b.ts, 0, 18))
17+
}

‎tests/baselines/reference/allowSyntheticDefaultImports2.types‎

Lines changed: 18 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,18 @@
1+
=== tests/cases/compiler/a.ts ===
2+
import Namespace from "./b";
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>Namespace : typeof Namespace
4+
5+
export var x = new Namespace.Foo();
6+
>x : Namespace.Foo
7+
>new Namespace.Foo() : Namespace.Foo
8+
>Namespace.Foo : typeof Namespace.Foo
9+
>Namespace : typeof Namespace
10+
>Foo : typeof Namespace.Foo
11+
12+
=== tests/cases/compiler/b.ts ===
13+
export class Foo {
14+
>Foo : Foo
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member: string;
17+
>member : string
18+
}

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