Fix declaration emit for negative number property declarations

andrewbranch · andrewbranch · commit 17f6f77de5dc · 2019-06-26T11:49:45.000-07:00
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
@@ -4652,6 +4652,9 @@ namespace ts {
                     if (!isIdentifierText(name, compilerOptions.target) && !isNumericLiteralName(name)) {
                         return `"${escapeString(name, CharacterCodes.doubleQuote)}"`;
                     }
+                    if (isNumericLiteralName(name) && startsWith(name, "-")) {
+                        return `[${name}]`;
+                    }
                     return name;
                 }
                 if (nameType.flags & TypeFlags.UniqueESSymbol) {
diff --git a/tests/cases/conformance/es6/computedProperties/computedPropertyNamesDeclarationEmit6_ES5.ts b/tests/cases/conformance/es6/computedProperties/computedPropertyNamesDeclarationEmit6_ES5.ts
@@ -0,0 +1,5 @@
+// @target: es5
+// @declaration: true
+var v = {
+  [-1]: {}
+}
diff --git a/tests/cases/conformance/es6/computedProperties/computedPropertyNamesDeclarationEmit6_ES6.ts b/tests/cases/conformance/es6/computedProperties/computedPropertyNamesDeclarationEmit6_ES6.ts
@@ -0,0 +1,5 @@
+// @target: es6
+// @declaration: true
+var v = {
+  [-1]: {}
+}

Original file line number	Diff line number	Diff line change
`@@ -4652,6 +4652,9 @@ namespace ts {`
`4652`	`4652`	`if (!isIdentifierText(name, compilerOptions.target) && !isNumericLiteralName(name)) {`
`4653`	`4653`	return `"${escapeString(name, CharacterCodes.doubleQuote)}"`;
`4654`	`4654`	`}`
	`4655`	`+ if (isNumericLiteralName(name) && startsWith(name, "-")) {`
	`4656`	+ return `[${name}]`;
	`4657`	`+ }`
`4655`	`4658`	`return name;`
`4656`	`4659`	`}`
`4657`	`4660`	`if (nameType.flags & TypeFlags.UniqueESSymbol) {`