Fix exception trying to push single element to optional chain array (#1257)

Perryvw · web-flow · commit ffcca572bfd1 · 2022-04-20T20:39:54.000+02:00
diff --git a/src/transformation/utils/typescript/index.ts b/src/transformation/utils/typescript/index.ts
@@ -25,9 +25,9 @@ export function findFirstNodeAbove<T extends ts.Node>(node: ts.Node, callback: (
 }
 
 export function findFirstNonOuterParent(node: ts.Node): ts.Node {
-    let current = node.parent;
+    let current = ts.getOriginalNode(node).parent;
     while (ts.isOuterExpression(current)) {
-        current = current.parent;
+        current = ts.getOriginalNode(current).parent;
     }
     return current;
 }
diff --git a/test/unit/builtins/array.spec.ts b/test/unit/builtins/array.spec.ts
@@ -497,6 +497,15 @@ test("array.push(...)", () => {
     `.expectToMatchJsResult();
 });
 
+// https://github.com/TypeScriptToLua/TypeScriptToLua/issues/1256
+test.each(["[1, 2, 3]", "undefined"])("array push on optional array", value => {
+    util.testFunction`
+        const arr = ${value} as number[] | undefined;
+        arr?.push(4);
+        return arr
+    `.expectToMatchJsResult();
+});
+
 test.each([
     { array: [1, 2, 3], expected: [3, 2] },
     { array: [1, 2, 3, null], expected: [3, 2] },

Original file line number	Diff line number	Diff line change
`@@ -25,9 +25,9 @@ export function findFirstNodeAbove<T extends ts.Node>(node: ts.Node, callback: (`
`25`	`25`	`}`
`26`	`26`
`27`	`27`	`export function findFirstNonOuterParent(node: ts.Node): ts.Node {`
`28`		`- let current = node.parent;`
	`28`	`+ let current = ts.getOriginalNode(node).parent;`
`29`	`29`	`while (ts.isOuterExpression(current)) {`
`30`		`- current = current.parent;`
	`30`	`+ current = ts.getOriginalNode(current).parent;`
`31`	`31`	`}`
`32`	`32`	`return current;`
`33`	`33`	`}`