diff --git a/test/unit/specs/composables/useMainStatus.spec.js b/test/unit/specs/composables/useMainStatus.spec.js
new file mode 100644
index 000000000..2ea2a772f
--- /dev/null
+++ b/test/unit/specs/composables/useMainStatus.spec.js
@@ -0,0 +1,30 @@
+import { createTestingPinia } from '@pinia/testing'
+import { setActivePinia } from 'pinia'
+
+import { useStatusesStore } from 'src/stores/statuses.js'
+
+import { useMainStatus } from 'src/composables/useMainStatus.js'
+
+describe('useMainStatus', () => {
+  beforeEach(() => {
+    setActivePinia(createTestingPinia())
+    useStatusesStore().allStatuses = new Map([
+      [1, { id: 1 }],
+      [2, { id: 2, retweeted_status: { id: 1 }}],
+    ])
+  })
+
+  it('non-repeat', () => {
+    const { status, mainStatus } = useMainStatus(1)
+
+    expect(status.value).to.eql({ id: 1 })
+    expect(mainStatus.value).to.eql({ id: 1 })
+  })
+
+  it('repeat', () => {
+    const { status, mainStatus } = useMainStatus(2)
+
+    expect(status.value).to.eql({ id: 2, retweeted_status: { id: 1 }})
+    expect(mainStatus.value).to.eql({ id: 1 })
+  })
+})