1 files changed, 43 insertions, 0 deletions
diff --git a/frontend/src/lib/coverage.test.ts b/frontend/src/lib/coverage.test.ts
new file mode 100644
index 0000000..cf59d54
--- /dev/null
+++ b/frontend/src/lib/coverage.test.ts
@@ -0,0 +1,43 @@
+import { describe, expect, it } from 'vitest';
+import { summarizeCoverage, type CoverageEntry } from './coverage';
+
+describe('summarizeCoverage', () => {
+  const entry = (o: Partial<CoverageEntry>): CoverageEntry => ({
+    instrument: '600000',
+    market: 'SH',
+    asset_type: 'stock',
+    requested_start: '',
+    requested_end: '',
+    actual_start: '',
+    actual_end: '',
+    row_count: 1,
+    ...o
+  });
+
+  it('lists unaligned starts without invented dates', () => {
+    const rows = [
+      entry({ instrument: 'A', actual_start: '2018-01-02', actual_end: '2024-12-31', requested_start: '2015-01-01' }),
+      entry({ instrument: 'B', actual_start: '2020-01-02', actual_end: '2024-12-31', requested_start: '2015-01-01' })
+    ];
+    const s = summarizeCoverage(rows);
+    expect(s.common.start).toBe('2020-01-02');
+    expect(s.common.end).toBe('2024-12-31');
+    expect(s.warnings.includes('B 起始数据较其他标的更晚（2020-01-02）')).toBe(true);
+  });
+
+  it('reports missing rows', () => {
+    const rows = [entry({ instrument: 'C', row_count: 0, actual_start: '', actual_end: '' })];
+    const s = summarizeCoverage(rows);
+    expect(s.warnings.includes('C 没有返回任何数据行')).toBe(true);
+    expect(s.common.start).toBeNull();
+  });
+
+  it('reports different end dates', () => {
+    const rows = [
+      entry({ instrument: 'A', actual_start: '2020-01-02', actual_end: '2024-12-31' }),
+      entry({ instrument: 'B', actual_start: '2020-01-02', actual_end: '2024-11-29' })
+    ];
+    const s = summarizeCoverage(rows);
+    expect(s.warnings.some((w) => w.includes('B 较早结束'))).toBe(true);
+  });
+});