test(transformer): fix merging options in fixtures update script

Author: overlookmotel

tasks/transform_conformance/snapshots/babel.snap.md

@@ -1,6 +1,6 @@
 commit: 54a8389f
 
-Passed: 437/846
+Passed: 439/846
 
 # All Passed:
 * babel-plugin-transform-class-static-block
@@ -276,7 +276,7 @@ x Output mismatch
 x Output mismatch
 
 
-# babel-plugin-transform-class-properties (110/264)
+# babel-plugin-transform-class-properties (112/264)
 * assumption-constantSuper/complex-super-class/input.js
 x Output mismatch
 
@@ -795,9 +795,6 @@ x Output mismatch
 * private-loose/update/input.js
 x Output mismatch
 
-* public/arrow-static-this-without-transform/input.js
-x Output mismatch
-
 * public/call/input.js
 Scope children mismatch:
 after transform: ScopeId(1): [ScopeId(2), ScopeId(3), ScopeId(4)]
@@ -901,9 +898,6 @@ rebuilt        : ScopeId(2): Some(ScopeId(0))
 * public/super-with-collision/input.js
 x Output mismatch
 
-* public-loose/arrow-static-this-without-transform/input.js
-x Output mismatch
-
 * public-loose/class-shadow-builtins/input.mjs
 x Output mismatch
 

tasks/transform_conformance/update_fixtures.js

@@ -110,7 +110,7 @@ async function updateDir(dirPath, options, hasChangedOptions) {
       await backupFile(path);
       await writeFile(path, JSON.stringify(localOptions, null, 2) + '\n');
     }
-    options = mergeOptions(options, localOptions);
+    options = { ...options, ...localOptions };
   }
 
   // Run Babel with updated options/input
@@ -154,58 +154,6 @@ function updateOptions(options) {
   return hasChangedOptions;
 }
 
-/**
- * Merge `options` into `parentOptions`.
- * Returns merged options object. Does not mutate either input.
- * @param {Object} parentOptions - Parent options
- * @param {Object} options - Local options
- * @returns {Object} - Merged options object
- */
-function mergeOptions(parentOptions, options) {
-  parentOptions = { ...parentOptions };
-
-  function merge(key) {
-    if (!options[key]) return;
-
-    if (!parentOptions[key]) {
-      parentOptions[key] = options[key];
-      return;
-    }
-
-    parentOptions[key] = [...parentOptions[key]];
-
-    const parentPluginIndexes = new Map();
-    for (const [index, plugin] of parentOptions[key].entries()) {
-      parentPluginIndexes.set(getName(plugin), index);
-    }
-
-    for (const plugin of options[key]) {
-      const pluginName = getName(plugin);
-      const parentPluginIndex = parentPluginIndexes.get(pluginName);
-      if (parentPluginIndex !== undefined) {
-        parentOptions[key][parentPluginIndex] = plugin;
-      } else {
-        parentOptions[key].push(plugin);
-      }
-    }
-  }
-
-  merge('presets');
-  merge('plugins');
-
-  if (options.assumptions) {
-    parentOptions.assumptions = { ...parentOptions.assumptions, ...options.assumptions };
-  }
-
-  for (const [key, value] of Object.entries(options)) {
-    if (key === 'plugins' || key === 'presets' || key === 'assumptions') continue;
-    if (Object.hasOwn(parentOptions, key)) throw new Error(`Clash: ${key}`);
-    parentOptions[key] = value;
-  }
-
-  return parentOptions;
-}
-
 /**
  * Transform input with Babel and save to output file.
  * @param {string} inputPath - Path of input file