Improve test coverage (#458)

Improving test coverage with additional tests (generated by copilot).


Before
<img width="1092" height="1203" alt="image"
src="https://github.com/user-attachments/assets/2b0b0515-01a9-476a-b78c-67e08cb84b3c"
/>


After
<img width="982" height="759" alt="image"
src="https://github.com/user-attachments/assets/f9c68214-4c73-4047-bf0f-8c562969d156"
/>


## GitHub issue number
/
## **Associated Risks**
/
 
## ✅ **PR Checklist**

- [x] **I have read the [contribution
guidelines](https://github.com/microsoft/azure-devops-mcp/blob/main/CONTRIBUTING.md)**
- [x] **I have read the [code of conduct
guidelines](https://github.com/microsoft/azure-devops-mcp/blob/main/CODE_OF_CONDUCT.md)**
- [x] Title of the pull request is clear and informative.
- [x] 👌 Code hygiene
- [x] 🔭 Telemetry added, updated, or N/A
- [x] 📄 Documentation added, updated, or N/A
- [x] 🛡️ Automated tests added, or N/A

## 🧪 **How did you test it?**
Executed tests.

Author: nikolapeja6

test/src/tools/advsec.test.ts

@@ -438,6 +438,198 @@ describe("configureAdvSecTools", () => {
         undefined // continuationToken
       );
     });
+
+    it("should handle optional parameters correctly when not provided", async () => {
+      configureAdvSecTools(server, tokenProvider, connectionProvider);
+
+      const call = (server.tool as jest.Mock).mock.calls.find(([toolName]) => toolName === "advsec_get_alerts");
+      if (!call) throw new Error("advsec_get_alerts tool not registered");
+      const [, , , handler] = call;
+
+      const mockResult: PagedList<Alert> = [];
+      (mockAlertApi.getAlerts as jest.Mock).mockResolvedValue(mockResult);
+
+      // Test with minimal parameters - only required ones
+      const minimalParams = {
+        project: "test-project",
+        repository: "test-repo",
+      };
+
+      await handler(minimalParams);
+
+      // When optional parameters aren't provided, they remain undefined
+      expect(mockAlertApi.getAlerts).toHaveBeenLastCalledWith(
+        "test-project",
+        "test-repo",
+        undefined, // top (optional, no default applied by handler)
+        undefined, // orderBy (optional, no default applied by handler)
+        {}, // empty criteria object since no optional filters provided
+        undefined, // expand
+        undefined // continuationToken
+      );
+    });
+
+    it("should include all optional parameters when provided", async () => {
+      configureAdvSecTools(server, tokenProvider, connectionProvider);
+
+      const call = (server.tool as jest.Mock).mock.calls.find(([toolName]) => toolName === "advsec_get_alerts");
+      if (!call) throw new Error("advsec_get_alerts tool not registered");
+      const [, , , handler] = call;
+
+      const mockResult: PagedList<Alert> = [];
+      (mockAlertApi.getAlerts as jest.Mock).mockResolvedValue(mockResult);
+
+      // Test with all optional parameters provided
+      const allParamsParams = {
+        project: "test-project",
+        repository: "test-repo",
+        alertType: "dependency",
+        states: ["active", "dismissed"],
+        severities: ["high", "medium"],
+        ruleId: "rule123",
+        ruleName: "security-rule",
+        toolName: "CodeQL",
+        ref: "refs/heads/main",
+        onlyDefaultBranch: false,
+        top: 50,
+        orderBy: "id",
+        continuationToken: "token123",
+      };
+
+      await handler(allParamsParams);
+
+      expect(mockAlertApi.getAlerts).toHaveBeenLastCalledWith(
+        "test-project",
+        "test-repo",
+        50, // top
+        "id", // orderBy
+        expect.objectContaining({
+          alertType: AlertType.Dependency,
+          states: [State.Active, State.Dismissed],
+          severities: [Severity.High, Severity.Medium],
+          ruleId: "rule123",
+          ruleName: "security-rule",
+          toolName: "CodeQL",
+          ref: "refs/heads/main",
+          onlyDefaultBranch: false,
+        }),
+        undefined, // expand
+        "token123" // continuationToken
+      );
+
+      // Verify all optional fields are included
+      const lastCall = (mockAlertApi.getAlerts as jest.Mock).mock.calls[0];
+      const criteria = lastCall[4];
+      expect(criteria).toHaveProperty("alertType", AlertType.Dependency);
+      expect(criteria).toHaveProperty("states", [State.Active, State.Dismissed]);
+      expect(criteria).toHaveProperty("severities", [Severity.High, Severity.Medium]);
+      expect(criteria).toHaveProperty("ruleId", "rule123");
+      expect(criteria).toHaveProperty("ruleName", "security-rule");
+      expect(criteria).toHaveProperty("toolName", "CodeQL");
+      expect(criteria).toHaveProperty("ref", "refs/heads/main");
+      expect(criteria).toHaveProperty("onlyDefaultBranch", false);
+    });
+
+    it("should handle onlyDefaultBranch parameter correctly", async () => {
+      configureAdvSecTools(server, tokenProvider, connectionProvider);
+
+      const call = (server.tool as jest.Mock).mock.calls.find(([toolName]) => toolName === "advsec_get_alerts");
+      if (!call) throw new Error("advsec_get_alerts tool not registered");
+      const [, , , handler] = call;
+
+      const mockResult: PagedList<Alert> = [];
+      (mockAlertApi.getAlerts as jest.Mock).mockResolvedValue(mockResult);
+
+      // Test with onlyDefaultBranch explicitly set to false
+      const falseParams = {
+        project: "test-project",
+        repository: "test-repo",
+        onlyDefaultBranch: false,
+      };
+
+      await handler(falseParams);
+
+      expect(mockAlertApi.getAlerts).toHaveBeenLastCalledWith(
+        "test-project",
+        "test-repo",
+        undefined, // top (not provided)
+        undefined, // orderBy (not provided)
+        expect.objectContaining({
+          onlyDefaultBranch: false,
+        }),
+        undefined, // expand
+        undefined // continuationToken
+      );
+
+      // Test with onlyDefaultBranch explicitly set to true
+      const trueParams = {
+        project: "test-project",
+        repository: "test-repo",
+        onlyDefaultBranch: true,
+      };
+
+      await handler(trueParams);
+
+      expect(mockAlertApi.getAlerts).toHaveBeenLastCalledWith(
+        "test-project",
+        "test-repo",
+        undefined, // top (not provided)
+        undefined, // orderBy (not provided)
+        expect.objectContaining({
+          onlyDefaultBranch: true,
+        }),
+        undefined, // expand
+        undefined // continuationToken
+      );
+    });
+
+    it("should handle secret alerts without confidenceLevels or validity", async () => {
+      configureAdvSecTools(server, tokenProvider, connectionProvider);
+
+      const call = (server.tool as jest.Mock).mock.calls.find(([toolName]) => toolName === "advsec_get_alerts");
+      if (!call) throw new Error("advsec_get_alerts tool not registered");
+      const [, , , handler] = call;
+
+      const mockResult: PagedList<Alert> = [];
+      (mockAlertApi.getAlerts as jest.Mock).mockResolvedValue(mockResult);
+
+      // Test secret alert without confidenceLevels or validity explicitly provided
+      const secretWithoutParams = {
+        project: "test-project",
+        repository: "test-repo",
+        alertType: "secret",
+      };
+
+      await handler(secretWithoutParams);
+
+      const lastCall = (mockAlertApi.getAlerts as jest.Mock).mock.calls[0];
+      const criteria = lastCall[4];
+      expect(criteria).toHaveProperty("alertType", AlertType.Secret);
+      // confidenceLevels and validity should not be included if not explicitly provided
+      expect(criteria).not.toHaveProperty("confidenceLevels");
+      expect(criteria).not.toHaveProperty("validity");
+    });
+
+    it("should handle non-Error exception types", async () => {
+      configureAdvSecTools(server, tokenProvider, connectionProvider);
+
+      const call = (server.tool as jest.Mock).mock.calls.find(([toolName]) => toolName === "advsec_get_alerts");
+      if (!call) throw new Error("advsec_get_alerts tool not registered");
+      const [, , , handler] = call;
+
+      // Test with non-Error exception (string)
+      (mockAlertApi.getAlerts as jest.Mock).mockRejectedValue("String error");
+
+      const params = {
+        project: "test-project",
+        repository: "test-repo",
+      };
+
+      const result = await handler(params);
+
+      expect(result.isError).toBe(true);
+      expect(result.content[0].text).toContain("Error fetching Advanced Security alerts: Unknown error occurred");
+    });
   });
 
   describe("advsec_get_alert_details tool", () => {
@@ -487,6 +679,44 @@ describe("configureAdvSecTools", () => {
       expect(result.isError).toBeUndefined();
     });
 
+    it("should fetch specific alert details with ref parameter", async () => {
+      configureAdvSecTools(server, tokenProvider, connectionProvider);
+
+      const call = (server.tool as jest.Mock).mock.calls.find(([toolName]) => toolName === "advsec_get_alert_details");
+      if (!call) throw new Error("advsec_get_alert_details tool not registered");
+      const [, , , handler] = call;
+
+      const mockResult: Alert = {
+        alertId: 1,
+        state: State.Active,
+        severity: Severity.High,
+        alertType: AlertType.Code,
+        title: "Test security alert",
+      };
+
+      (mockAlertApi.getAlert as jest.Mock).mockResolvedValue(mockResult);
+
+      const params = {
+        project: "test-project",
+        repository: "test-repo",
+        alertId: 1,
+        ref: "refs/heads/feature-branch",
+      };
+
+      const result = await handler(params);
+
+      expect(mockAlertApi.getAlert).toHaveBeenCalledWith(
+        "test-project",
+        1,
+        "test-repo",
+        "refs/heads/feature-branch", // ref
+        undefined // expand
+      );
+
+      expect(result.content[0].text).toBe(JSON.stringify(mockResult, null, 2));
+      expect(result.isError).toBeUndefined();
+    });
+
     it("should handle API errors correctly", async () => {
       configureAdvSecTools(server, tokenProvider, connectionProvider);
 
@@ -510,6 +740,28 @@ describe("configureAdvSecTools", () => {
       expect(result.content[0].text).toContain("Error fetching alert details: Alert not found");
     });
 
+    it("should handle non-Error exception types", async () => {
+      configureAdvSecTools(server, tokenProvider, connectionProvider);
+
+      const call = (server.tool as jest.Mock).mock.calls.find(([toolName]) => toolName === "advsec_get_alert_details");
+      if (!call) throw new Error("advsec_get_alert_details tool not registered");
+      const [, , , handler] = call;
+
+      // Test with non-Error exception (string)
+      (mockAlertApi.getAlert as jest.Mock).mockRejectedValue("String error");
+
+      const params = {
+        project: "test-project",
+        repository: "test-repo",
+        alertId: 999,
+      };
+
+      const result = await handler(params);
+
+      expect(result.isError).toBe(true);
+      expect(result.content[0].text).toContain("Error fetching alert details: Unknown error occurred");
+    });
+
     it("should handle null API results correctly", async () => {
       configureAdvSecTools(server, tokenProvider, connectionProvider);