fix: requeue flipped paths in yoda

j4k0xb · Dec 29, 2023 · aa262c0 · aa262c0
1 parent b9180a0
commit aa262c0
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Showing 2 changed files with 31 additions and 7 deletions.
diff --git a/packages/webcrack/src/unminify/test/unminify.test.ts b/packages/webcrack/src/unminify/test/unminify.test.ts
@@ -0,0 +1,18 @@
+import { test } from 'vitest';
+import unminify from '..';
+import { testTransform } from '../../../test';
+
+const expectJS = testTransform(unminify);
+
+test('mixed typeof-undefined and yoda', () =>
+  expectJS(`
+    typeof x < "u";
+    "u" > typeof x;
+    typeof x > "u";
+    "u" < typeof x;
+  `).toMatchInlineSnapshot(`
+    typeof x !== "undefined";
+    typeof x !== "undefined";
+    typeof x === "undefined";
+    typeof x === "undefined";
+  `));
diff --git a/packages/webcrack/src/unminify/transforms/yoda.ts b/packages/webcrack/src/unminify/transforms/yoda.ts
@@ -4,7 +4,7 @@ import { Transform } from '../../ast-utils';
 
 // https://eslint.org/docs/latest/rules/yoda and https://babeljs.io/docs/en/babel-plugin-minify-flip-comparisons
 
-const flippedOperators = {
+const FLIPPED_OPERATORS = {
   '==': '==',
   '===': '===',
   '!=': '!=',
@@ -24,7 +24,7 @@ export default {
   tags: ['safe'],
   visitor: () => {
     const matcher = m.binaryExpression(
-      m.or(...Object.values(flippedOperators)),
+      m.or(...Object.values(FLIPPED_OPERATORS)),
       m.or(
         m.stringLiteral(),
         m.numericLiteral(),
@@ -43,11 +43,17 @@ export default {
 
     return {
       BinaryExpression: {
-        exit({ node }) {
-          if (matcher.match(node)) {
-            [node.left, node.right] = [node.right, node.left as t.Expression];
-            node.operator =
-              flippedOperators[node.operator as keyof typeof flippedOperators];
+        exit(path) {
+          if (matcher.match(path.node)) {
+            path.replaceWith(
+              t.binaryExpression(
+                FLIPPED_OPERATORS[
+                  path.node.operator as keyof typeof FLIPPED_OPERATORS
+                ],
+                path.node.right,
+                path.node.left as t.Expression,
+              ),
+            );
             this.changes++;
           }
         },