fix: update frontend unit tests to improve coverage and handle edge cases

frontend/src/api/__tests__/client.test.ts

@@ -90,6 +90,38 @@ describe('api client', () => {
     expect(error.message).toBe('Bad request')
   })
 
+  it('keeps original message when response payload is not an object', async () => {
+    const error: ResponseError = {
+      response: { data: 'plain text error' as unknown as Record<string, unknown> },
+      config: { url: '/test' },
+      message: 'Original',
+    }
+
+    const handler = capturedHandlers.onRejected
+    expect(handler).toBeDefined()
+
+    const resultPromise = handler ? handler(error) : Promise.reject(new Error('handler missing'))
+
+    await expect(resultPromise).rejects.toBe(error)
+    expect(error.message).toBe('Original')
+  })
+
+  it('uses error field over message field when both exist', async () => {
+    const error: ResponseError = {
+      response: { data: { error: 'Preferred error', message: 'Secondary message' } },
+      config: { url: '/test' },
+      message: 'Original',
+    }
+
+    const handler = capturedHandlers.onRejected
+    expect(handler).toBeDefined()
+
+    const resultPromise = handler ? handler(error) : Promise.reject(new Error('handler missing'))
+
+    await expect(resultPromise).rejects.toBe(error)
+    expect(error.message).toBe('Preferred error')
+  })
+
   it('invokes auth error handler on 401 outside auth endpoints', async () => {
     const onAuthError = vi.fn()
     const warnSpy = vi.spyOn(console, 'warn').mockImplementation(() => {})
@@ -137,4 +169,37 @@ describe('api client', () => {
 
     warnSpy.mockRestore()
   })
+
+  it('does not invoke auth error handler when status is not 401', async () => {
+    const onAuthError = vi.fn()
+    const warnSpy = vi.spyOn(console, 'warn').mockImplementation(() => {})
+
+    setAuthErrorHandler(onAuthError)
+
+    const error: ResponseError = {
+      response: { status: 403, data: { message: 'Forbidden' } },
+      config: { url: '/proxy-hosts' },
+      message: 'Original',
+    }
+
+    const handler = capturedHandlers.onRejected
+    expect(handler).toBeDefined()
+
+    const resultPromise = handler ? handler(error) : Promise.reject(new Error('handler missing'))
+
+    await expect(resultPromise).rejects.toBe(error)
+    expect(onAuthError).not.toHaveBeenCalled()
+    expect(warnSpy).not.toHaveBeenCalled()
+
+    warnSpy.mockRestore()
+  })
+
+  it('passes through successful responses via fulfilled interceptor', () => {
+    const responsePayload = { data: { ok: true } }
+    const fulfilled = capturedHandlers.onFulfilled
+
+    expect(fulfilled).toBeDefined()
+    const result = fulfilled ? fulfilled(responsePayload) : undefined
+    expect(result).toBe(responsePayload)
+  })
 })

frontend/src/api/__tests__/import.test.ts

@@ -37,6 +37,14 @@ describe('import API', () => {
     expect(result).toEqual(mockResponse);
   });
 
+  it('uploadCaddyfilesMulti accepts empty file arrays', async () => {
+    mockedPost.mockResolvedValue({ data: { preview: { hosts: [], conflicts: [], errors: [] } } });
+
+    const result = await uploadCaddyfilesMulti([]);
+    expect(client.post).toHaveBeenCalledWith('/import/upload-multi', { files: [] });
+    expect(result).toEqual({ preview: { hosts: [], conflicts: [], errors: [] } });
+  });
+
   it('getImportPreview gets preview', async () => {
     const mockResponse = { preview: { hosts: [] } };
     mockedGet.mockResolvedValue({ data: mockResponse });
@@ -70,6 +78,20 @@ describe('import API', () => {
     expect(client.post).toHaveBeenCalledWith('/import/cancel');
   });
 
+  it('forwards commitImport errors', async () => {
+    const error = new Error('commit failed');
+    mockedPost.mockRejectedValue(error);
+
+    await expect(commitImport('uuid-123', {}, {})).rejects.toBe(error);
+  });
+
+  it('forwards cancelImport errors', async () => {
+    const error = new Error('cancel failed');
+    mockedPost.mockRejectedValue(error);
+
+    await expect(cancelImport()).rejects.toBe(error);
+  });
+
   it('getImportStatus gets status', async () => {
     const mockResponse = { has_pending: true };
     mockedGet.mockResolvedValue({ data: mockResponse });
@@ -85,4 +107,11 @@ describe('import API', () => {
     const result = await getImportStatus();
     expect(result).toEqual({ has_pending: false });
   });
+
+  it('getImportStatus returns false on non-Error rejections', async () => {
+    mockedGet.mockRejectedValue('network down');
+
+    const result = await getImportStatus();
+    expect(result).toEqual({ has_pending: false });
+  });
 });

frontend/src/api/__tests__/securityHeaders.test.ts

@@ -39,6 +39,15 @@ describe('securityHeadersApi', () => {
     expect(result).toEqual(mockProfile);
   });
 
+  it('getProfile accepts UUID string identifiers', async () => {
+    const mockProfile = { id: 2, uuid: 'profile-uuid', name: 'Profile UUID' };
+    mockedGet.mockResolvedValue({ data: { profile: mockProfile } });
+
+    const result = await securityHeadersApi.getProfile('profile-uuid');
+    expect(client.get).toHaveBeenCalledWith('/security/headers/profiles/profile-uuid');
+    expect(result).toEqual(mockProfile);
+  });
+
   it('createProfile creates a profile', async () => {
     const newProfile = { name: 'New Profile' };
     const mockResponse = { id: 1, ...newProfile };
@@ -66,6 +75,13 @@ describe('securityHeadersApi', () => {
     expect(client.delete).toHaveBeenCalledWith('/security/headers/profiles/1');
   });
 
+  it('forwards API errors from listProfiles', async () => {
+    const error = new Error('backend unavailable');
+    mockedGet.mockRejectedValue(error);
+
+    await expect(securityHeadersApi.listProfiles()).rejects.toBe(error);
+  });
+
   it('getPresets returns presets', async () => {
     const mockPresets = [{ name: 'Basic' }];
     mockedGet.mockResolvedValue({ data: { presets: mockPresets } });