test(P02): backend test coverage — 4 new suites, 353 tests passing

---ci---
project: ci
phase: 2
milestone: v0.5
status: complete
decisions:
  - id: D-024
    decision: Phase 2 Backend Test Coverage complete
    rationale: All TEST requirements covered; 31 suites, 353 tests passing
    confidence: 0.95
    alternatives: []
requirements:
  covered: [TEST-01, TEST-02, TEST-03, TEST-04]
---/ci---

src/backends/ollama-base.test.ts

@@ -0,0 +1,229 @@
+import * as fs from "node:fs";
+import * as path from "node:path";
+import * as os from "node:os";
+import { OllamaBaseBackend, OllamaMessage, OllamaChatResponse } from "../backends/ollama-base.js";
+import { ToolRegistry } from "../backends/tool-registry.js";
+import { BackendRequest } from "../backends/types.js";
+
+class TestableOllamaBaseBackend extends OllamaBaseBackend {
+  readonly name = "test-base";
+  private mockResponse: OllamaChatResponse;
+  private callCount: number;
+
+  constructor(mockResponse: OllamaChatResponse) {
+    super(undefined);
+    this.mockResponse = mockResponse;
+    this.callCount = 0;
+  }
+
+  async isAvailable(): Promise<boolean> {
+    return true;
+  }
+
+  getCallCount(): number {
+    return this.callCount;
+  }
+
+  protected async callModel(
+    messages: OllamaMessage[],
+    model: string,
+    toolRegistry: ToolRegistry
+  ): Promise<OllamaChatResponse> {
+    this.callCount++;
+    return this.mockResponse;
+  }
+
+  protected resolveModel(): string {
+    return "test-model";
+  }
+}
+
+describe("OllamaBaseBackend", () => {
+  let tempDir: string;
+
+  beforeEach(() => {
+    tempDir = fs.mkdtempSync(path.join(os.tmpdir(), "ci-ollama-base-test-"));
+  });
+
+  afterEach(() => {
+    fs.rmSync(tempDir, { recursive: true, force: true });
+  });
+
+  it("returns success when model responds without tool calls", async () => {
+    const mockResponse: OllamaChatResponse = {
+      choices: [{
+        message: {
+          content: '{"success": true, "output": "task completed"}',
+        },
+      }],
+      usage: { prompt_tokens: 10, completion_tokens: 20, total_tokens: 30 },
+    };
+
+    const backend = new TestableOllamaBaseBackend(mockResponse);
+    const request: BackendRequest = {
+      persona: "executor",
+      workflow: "execute",
+      task: "Do something",
+      context: {
+        project_path: tempDir,
+        phase: 1,
+        stage: "execute",
+        specification: "",
+        config_path: "",
+      },
+      autonomy: "full",
+    };
+
+    const result = await backend.execute(request);
+    expect(result.success).toBe(true);
+    expect(result.output).toContain("task completed");
+  });
+
+  it("handles tool calls in response", async () => {
+    const writePath = path.join(tempDir, "output.txt");
+    const responses: OllamaChatResponse[] = [
+      {
+        choices: [{
+          message: {
+            content: "",
+            tool_calls: [{
+              function: { name: "writeFile", arguments: JSON.stringify({ path: writePath, content: "hello" }) },
+            }],
+          },
+        }],
+        usage: { prompt_tokens: 10, completion_tokens: 5, total_tokens: 15 },
+      },
+      {
+        choices: [{
+          message: {
+            content: '{"success": true, "output": "file written"}',
+          },
+        }],
+        usage: { prompt_tokens: 5, completion_tokens: 10, total_tokens: 15 },
+      },
+    ];
+
+    let callIndex = 0;
+    class ToolCallBackend extends OllamaBaseBackend {
+      readonly name = "tool-call-test";
+      constructor() {
+        super(undefined);
+      }
+      async isAvailable(): Promise<boolean> { return true; }
+      protected async callModel(): Promise<OllamaChatResponse> {
+        return responses[callIndex++];
+      }
+      protected resolveModel(): string { return "test-model"; }
+    }
+
+    const backend = new ToolCallBackend();
+    const request: BackendRequest = {
+      persona: "executor",
+      workflow: "execute",
+      task: "Write a file",
+      context: {
+        project_path: tempDir,
+        phase: 1,
+        stage: "execute",
+        specification: "",
+        config_path: "",
+      },
+      autonomy: "full",
+    };
+
+    const result = await backend.execute(request);
+    expect(result.success).toBe(true);
+    expect(fs.existsSync(writePath)).toBe(true);
+    expect(fs.readFileSync(writePath, "utf-8")).toBe("hello");
+    expect(result.artifacts.length).toBe(1);
+    expect(result.artifacts[0].path).toBe(writePath);
+  });
+
+  it("stops after max tool rounds", async () => {
+    const alwaysToolCall: OllamaChatResponse = {
+      choices: [{
+        message: {
+          content: "",
+          tool_calls: [{
+            function: { name: "readFile", arguments: JSON.stringify({ path: "/etc/hostname" }) },
+          }],
+        },
+      }],
+      usage: { prompt_tokens: 1, completion_tokens: 1, total_tokens: 2 },
+    };
+
+    class InfiniteLoopBackend extends OllamaBaseBackend {
+      readonly name = "infinite-loop";
+      private callCount = 0;
+      constructor() {
+        super(undefined);
+      }
+      async isAvailable(): Promise<boolean> { return true; }
+      protected async callModel(): Promise<OllamaChatResponse> {
+        this.callCount++;
+        return alwaysToolCall;
+      }
+      protected resolveModel(): string { return "test-model"; }
+      getCallCount() { return this.callCount; }
+    }
+
+    const backend = new InfiniteLoopBackend();
+    const request: BackendRequest = {
+      persona: "executor",
+      workflow: "execute",
+      task: "Infinite loop test",
+      context: {
+        project_path: tempDir,
+        phase: 1,
+        stage: "execute",
+        specification: "",
+        config_path: "",
+      },
+      autonomy: "full",
+    };
+
+    const result = await backend.execute(request);
+    expect(result.output).toContain("maximum rounds");
+    expect(backend.getCallCount()).toBe(50);
+  });
+
+  it("handles error from callModel gracefully", async () => {
+    class ErrorBackend extends OllamaBaseBackend {
+      readonly name = "error-backend";
+      constructor() {
+        super(undefined);
+      }
+      async isAvailable(): Promise<boolean> { return true; }
+      protected async callModel(): Promise<OllamaChatResponse> {
+        throw new Error("Model connection failed");
+      }
+      protected resolveModel(): string { return "test-model"; }
+    }
+
+    const backend = new ErrorBackend();
+    const request: BackendRequest = {
+      persona: "executor",
+      workflow: "execute",
+      task: "Fail test",
+      context: {
+        project_path: tempDir,
+        phase: 1,
+        stage: "execute",
+        specification: "",
+        config_path: "",
+      },
+      autonomy: "full",
+    };
+
+    const result = await backend.execute(request);
+    expect(result.success).toBe(false);
+    expect(result.error).toContain("Backend execution failed");
+  });
+
+  it("modelProfileToModel selects smallest for speed", () => {
+    const backend = new TestableOllamaBaseBackend({} as OllamaChatResponse);
+    const models = ["llama3.1:70b", "llama3.1:8b", "llama3.1"];
+    const selected = (backend as unknown as { modelProfileToModel: (p: string, m: string[]) => string }).modelProfileToModel("speed", models);
+    expect(selected).toBe("llama3.1");
+  });
+});