feat: add mergeSnapshotOptions utility to @percy/sdk-utils

packages/sdk-utils/src/index.js

@@ -10,6 +10,7 @@ import postBuildEvents from './post-build-event.js';
 import flushSnapshots from './flush-snapshots.js';
 import captureAutomateScreenshot from './post-screenshot.js';
 import getResponsiveWidths from './get-responsive-widths.js';
+import mergeSnapshotOptions from './merge-snapshot-options.js';
 
 export {
   logger,
@@ -23,7 +24,8 @@ export {
   flushSnapshots,
   captureAutomateScreenshot,
   postBuildEvents,
-  getResponsiveWidths
+  getResponsiveWidths,
+  mergeSnapshotOptions
 };
 
 // export the namespace by default

packages/sdk-utils/src/merge-snapshot-options.js

@@ -0,0 +1,10 @@
+import percy from './percy-info.js';
+
+// Merges .percy.yml config snapshot options with per-snapshot options.
+// Per-snapshot options take priority over config options.
+export function mergeSnapshotOptions(options) {
+  const configOptions = percy?.config?.snapshot || {};
+  return { ...configOptions, ...options };
+}
+
+export default mergeSnapshotOptions;

packages/sdk-utils/test/index.test.js

@@ -648,4 +648,49 @@ describe('SDK Utils', () => {
       ]);
     });
   });
+
+  describe('mergeSnapshotOptions(options)', () => {
+    let { mergeSnapshotOptions } = utils;
+
+    beforeEach(async () => {
+      await helpers.setupTest();
+      await utils.isPercyEnabled();
+    });
+
+    it('merges config snapshot options with per-snapshot options', () => {
+      const result = mergeSnapshotOptions({ enableJavaScript: true });
+      expect(result.enableJavaScript).toBe(true);
+      expect(result.widths).toEqual([375, 1280]);
+    });
+
+    it('gives per-snapshot options priority over config', () => {
+      const result = mergeSnapshotOptions({ widths: [768] });
+      expect(result.widths).toEqual([768]);
+    });
+
+    it('returns config options when no per-snapshot options are provided', () => {
+      const result = mergeSnapshotOptions();
+      expect(result.widths).toEqual([375, 1280]);
+    });
+
+    it('returns empty object when config.snapshot is undefined and no options given', () => {
+      const savedConfig = utils.percy.config;
+      utils.percy.config = { ...savedConfig, snapshot: undefined };
+
+      const result = mergeSnapshotOptions();
+      expect(result).toEqual({});
+
+      utils.percy.config = savedConfig;
+    });
+
+    it('returns only per-snapshot options when config.snapshot is undefined', () => {
+      const savedConfig = utils.percy.config;
+      utils.percy.config = { ...savedConfig, snapshot: undefined };
+
+      const result = mergeSnapshotOptions({ enableJavaScript: true });
+      expect(result).toEqual({ enableJavaScript: true });
+
+      utils.percy.config = savedConfig;
+    });
+  });
 });