Avoid exporting anonymous identifiers (#756)

hazzard993 · ark120202 · Perryvw · commit 757302b89d69 · 2019-12-03T20:09:30.000+01:00
* Avoid exporting anonymous identifiers

* Use existing test for anonymous destructuring

* Remove TODO for issue 32656 with test filter

* Update test/unit/destructuring.spec.ts

Co-Authored-By: ark120202 &lt;ark120202@gmail.com&gt;

* Update test/unit/destructuring.spec.ts

Co-Authored-By: ark120202 &lt;ark120202@gmail.com&gt;
diff --git a/src/LuaAST.ts b/src/LuaAST.ts
@@ -829,6 +829,7 @@ export function createMethodCallExpression(
 
 export interface Identifier extends Expression {
     kind: SyntaxKind.Identifier;
+    exportable: boolean;
     text: string;
     originalName?: string;
     symbolId?: SymbolId;
@@ -846,6 +847,7 @@ export function createIdentifier(
     parent?: Node
 ): Identifier {
     const expression = createNode(SyntaxKind.Identifier, tsOriginal, parent) as Identifier;
+    expression.exportable = true;
     expression.text = text;
     expression.symbolId = symbolId;
     expression.originalName = originalName;
@@ -858,6 +860,7 @@ export function cloneIdentifier(identifier: Identifier, tsOriginal?: ts.Node): I
 
 export function createAnonymousIdentifier(tsOriginal?: ts.Node, parent?: Node): Identifier {
     const expression = createNode(SyntaxKind.Identifier, tsOriginal, parent) as Identifier;
+    expression.exportable = false;
     expression.text = "____";
     return expression;
 }
diff --git a/src/LuaTransformer.ts b/src/LuaTransformer.ts
@@ -5480,6 +5480,10 @@ export class LuaTransformer {
         identifier: tstl.Identifier,
         exportScope?: ts.SourceFile | ts.ModuleDeclaration
     ): tstl.AssignmentLeftHandSideExpression {
+        if (!identifier.exportable) {
+            return identifier;
+        }
+
         const exportTable =
             exportScope && ts.isModuleDeclaration(exportScope)
                 ? this.createModuleLocalNameIdentifier(exportScope)
diff --git a/test/unit/destructuring.spec.ts b/test/unit/destructuring.spec.ts
@@ -51,16 +51,11 @@ test.each(testCases)("in variable declaration (%p)", ({ binding, value }) => {
     `.expectToMatchJsResult();
 });
 
-// TODO: https://github.com/TypeScriptToLua/TypeScriptToLua/issues/695
-// TODO: https://github.com/microsoft/TypeScript/issues/32656
-test.each(testCases.filter(x => x.binding !== "[x, , y]" && x.binding !== "{ x, ...rest }"))(
-    "in exported variable declaration (%p)",
-    ({ binding, value }) => {
-        util.testModule`
-            export const ${binding} = ${value};
-        `.expectToMatchJsResult();
-    }
-);
+test.each(testCases)("in exported variable declaration (%p)", ({ binding, value }) => {
+    util.testModule`
+        export const ${binding} = ${value};
+    `.expectToMatchJsResult();
+});
 
 const assignmentTestCases = [
     ...testCases,
