test(share): buildShareText 单测（单换行/空字段/无url，分享重构 §9）

entry/src/test/List.test.ets

@@ -1,9 +1,11 @@
 import localUnitTest from './LocalUnit.test';
 import bridgeTest from './Bridge.test';
 import versionResolverTest from './VersionResolver.test';
+import shareTextTest from './ShareText.test';
 
 export default function testsuite() {
   localUnitTest();
   bridgeTest();
   versionResolverTest();
+  shareTextTest();
 }

entry/src/test/ShareText.test.ets

@@ -0,0 +1,23 @@
+import { describe, it, expect } from '@ohos/hypium';
+import { buildShareText } from 'feature_capabilities';
+
+/**
+ * 分享文本拼接单测（分享重构 §5.1）。
+ * 规则：title\ndescription，单换行、三端一致、不含 url；空字段跳过。
+ */
+export default function shareTextTest() {
+  describe('buildShareText', () => {
+    it('title_and_description_single_newline', 0, () => {
+      expect(buildShareText('标题', '描述')).assertEqual('标题\n描述');
+    });
+    it('title_only', 0, () => {
+      expect(buildShareText('标题', '')).assertEqual('标题');
+    });
+    it('description_only', 0, () => {
+      expect(buildShareText('', '描述')).assertEqual('描述');
+    });
+    it('both_empty_returns_empty', 0, () => {
+      expect(buildShareText('', '')).assertEqual('');
+    });
+  });
+}