Merge pull request #3374 from Microsoft/emitParenthesizedTypeAssertion

Emit parenthesized type assertion

Author: JsonFreeman

src/compiler/emitter.ts

@@ -1644,6 +1644,12 @@ var __param = (this && this.__param) || function (paramIndex, decorator) {
             }
 
             function parenthesizeForAccess(expr: Expression): LeftHandSideExpression {
+                // When diagnosing whether the expression needs parentheses, the decision should be based
+                // on the innermost expression in a chain of nested type assertions.
+                while (expr.kind === SyntaxKind.TypeAssertionExpression) {
+                    expr = (<TypeAssertion>expr).expression;
+                }
+
                 // isLeftHandSideExpression is almost the correct criterion for when it is not necessary
                 // to parenthesize the expression before a dot. The known exceptions are:
                 //
@@ -1652,7 +1658,10 @@ var __param = (this && this.__param) || function (paramIndex, decorator) {
                 //    NumberLiteral
                 //       1.x            -> not the same as (1).x
                 //
-                if (isLeftHandSideExpression(expr) && expr.kind !== SyntaxKind.NewExpression && expr.kind !== SyntaxKind.NumericLiteral) {
+                if (isLeftHandSideExpression(expr) &&
+                    expr.kind !== SyntaxKind.NewExpression &&
+                    expr.kind !== SyntaxKind.NumericLiteral) {
+
                     return <LeftHandSideExpression>expr;
                 }
                 let node = <ParenthesizedExpression>createSynthesizedNode(SyntaxKind.ParenthesizedExpression);
@@ -1906,7 +1915,10 @@ var __param = (this && this.__param) || function (paramIndex, decorator) {
             }
 
             function emitParenExpression(node: ParenthesizedExpression) {
-                if (!node.parent || node.parent.kind !== SyntaxKind.ArrowFunction) {
+                // If the node is synthesized, it means the emitter put the parentheses there,
+                // not the user. If we didn't want them, the emitter would not have put them
+                // there.
+                if (!nodeIsSynthesized(node) && node.parent.kind !== SyntaxKind.ArrowFunction) {
                     if (node.expression.kind === SyntaxKind.TypeAssertionExpression) {
                         let operand = (<TypeAssertion>node.expression).expression;
 

tests/baselines/reference/destructuringTypeAssertionsES5_1.errors.txt

@@ -0,0 +1,7 @@
+tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_1.ts(1,18): error TS2304: Cannot find name 'foo'.
+
+
+==== tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_1.ts (1 errors) ====
+    var { x } = <any>foo();
+                     ~~~
+!!! error TS2304: Cannot find name 'foo'.

tests/baselines/reference/destructuringTypeAssertionsES5_1.js

@@ -0,0 +1,5 @@
+//// [destructuringTypeAssertionsES5_1.ts]
+var { x } = <any>foo();
+
+//// [destructuringTypeAssertionsES5_1.js]
+var x = foo().x;

tests/baselines/reference/destructuringTypeAssertionsES5_2.errors.txt

@@ -0,0 +1,7 @@
+tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_2.ts(1,19): error TS2304: Cannot find name 'foo'.
+
+
+==== tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_2.ts (1 errors) ====
+    var { x } = (<any>foo());
+                      ~~~
+!!! error TS2304: Cannot find name 'foo'.

tests/baselines/reference/destructuringTypeAssertionsES5_2.js

@@ -0,0 +1,5 @@
+//// [destructuringTypeAssertionsES5_2.ts]
+var { x } = (<any>foo());
+
+//// [destructuringTypeAssertionsES5_2.js]
+var x = foo().x;

tests/baselines/reference/destructuringTypeAssertionsES5_3.errors.txt

@@ -0,0 +1,7 @@
+tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_3.ts(1,19): error TS2304: Cannot find name 'foo'.
+
+
+==== tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_3.ts (1 errors) ====
+    var { x } = <any>(foo());
+                      ~~~
+!!! error TS2304: Cannot find name 'foo'.

tests/baselines/reference/destructuringTypeAssertionsES5_3.js

@@ -0,0 +1,5 @@
+//// [destructuringTypeAssertionsES5_3.ts]
+var { x } = <any>(foo());
+
+//// [destructuringTypeAssertionsES5_3.js]
+var x = (foo()).x;

tests/baselines/reference/destructuringTypeAssertionsES5_4.errors.txt

@@ -0,0 +1,7 @@
+tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_4.ts(1,23): error TS2304: Cannot find name 'foo'.
+
+
+==== tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_4.ts (1 errors) ====
+    var { x } = <any><any>foo();
+                          ~~~
+!!! error TS2304: Cannot find name 'foo'.

tests/baselines/reference/destructuringTypeAssertionsES5_4.js

@@ -0,0 +1,5 @@
+//// [destructuringTypeAssertionsES5_4.ts]
+var { x } = <any><any>foo();
+
+//// [destructuringTypeAssertionsES5_4.js]
+var x = foo().x;

tests/baselines/reference/destructuringTypeAssertionsES5_5.js

@@ -0,0 +1,5 @@
+//// [destructuringTypeAssertionsES5_5.ts]
+var { x } = <any>0;
+
+//// [destructuringTypeAssertionsES5_5.js]
+var x = (0).x;

tests/baselines/reference/destructuringTypeAssertionsES5_5.symbols

@@ -0,0 +1,4 @@
+=== tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_5.ts ===
+var { x } = <any>0;
+>x : Symbol(x, Decl(destructuringTypeAssertionsES5_5.ts, 0, 5))
+

tests/baselines/reference/destructuringTypeAssertionsES5_5.types

@@ -0,0 +1,6 @@
+=== tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_5.ts ===
+var { x } = <any>0;
+>x : any
+><any>0 : any
+>0 : number
+

tests/baselines/reference/destructuringTypeAssertionsES5_6.errors.txt

@@ -0,0 +1,7 @@
+tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_6.ts(1,22): error TS2304: Cannot find name 'Foo'.
+
+
+==== tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_6.ts (1 errors) ====
+    var { x } = <any>new Foo;
+                         ~~~
+!!! error TS2304: Cannot find name 'Foo'.

tests/baselines/reference/destructuringTypeAssertionsES5_6.js

@@ -0,0 +1,5 @@
+//// [destructuringTypeAssertionsES5_6.ts]
+var { x } = <any>new Foo;
+
+//// [destructuringTypeAssertionsES5_6.js]
+var x = (new Foo).x;

tests/baselines/reference/destructuringTypeAssertionsES5_7.errors.txt

@@ -0,0 +1,7 @@
+tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_7.ts(1,27): error TS2304: Cannot find name 'Foo'.
+
+
+==== tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_7.ts (1 errors) ====
+    var { x } = <any><any>new Foo;
+                              ~~~
+!!! error TS2304: Cannot find name 'Foo'.

tests/baselines/reference/destructuringTypeAssertionsES5_7.js

@@ -0,0 +1,5 @@
+//// [destructuringTypeAssertionsES5_7.ts]
+var { x } = <any><any>new Foo;
+
+//// [destructuringTypeAssertionsES5_7.js]
+var x = (new Foo).x;

tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_1.ts

@@ -0,0 +1,2 @@
+//@target: ES5
+var { x } = <any>foo();

tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_2.ts

@@ -0,0 +1,2 @@
+//@target: ES5
+var { x } = (<any>foo());

tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_3.ts

@@ -0,0 +1,2 @@
+//@target: ES5
+var { x } = <any>(foo());

tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_4.ts

@@ -0,0 +1,2 @@
+//@target: ES5
+var { x } = <any><any>foo();

tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_5.ts

@@ -0,0 +1,2 @@
+//@target: ES5
+var { x } = <any>0;

tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_6.ts

@@ -0,0 +1,2 @@
+//@target: ES5
+var { x } = <any>new Foo;

tests/cases/conformance/es6/destructuring/destructuringTypeAssertionsES5_7.ts

@@ -0,0 +1,2 @@
+//@target: ES5
+var { x } = <any><any>new Foo;