fix(coding-agent): signalled fallback commits with a non-zero exit code

packages/coding-agent/test/commit-fallback-exit.test.ts

@@ -0,0 +1,114 @@
+/**
+ * The fallback commit path (agent failed / no proposal) must be signalled to
+ * callers so a degraded numstat commit is distinguishable from a legitimate
+ * single-commit decision (issue #7835).
+ */
+import { afterEach, describe, expect, it, vi } from "bun:test";
+import { getBundledModel } from "@oh-my-pi/pi-catalog/models";
+import { runAgenticCommit } from "@oh-my-pi/pi-coding-agent/commit/agentic";
+import * as agentModule from "@oh-my-pi/pi-coding-agent/commit/agentic/agent";
+import * as modelSelection from "@oh-my-pi/pi-coding-agent/commit/model-selection";
+import { Settings } from "@oh-my-pi/pi-coding-agent/config/settings";
+import * as sdkModule from "@oh-my-pi/pi-coding-agent/sdk";
+import * as gitModule from "@oh-my-pi/pi-coding-agent/utils/git";
+
+const NUMSTAT = [{ path: "src/a.ts", additions: 1, deletions: 0 }];
+
+// ModelRegistry's constructor performs provider discovery and storage access;
+// the commit pipeline only needs a registry that resolves no models.
+vi.mock("@oh-my-pi/pi-coding-agent/config/model-registry", () => ({
+	ModelRegistry: class MockModelRegistry {
+		constructor(_authStorage: never) {}
+		async refresh() {}
+	},
+}));
+
+function mockModelResolution() {
+	const model = getBundledModel("anthropic", "claude-sonnet-4-5");
+	if (!model) throw new Error("Expected claude-sonnet-4-5 model to exist");
+	vi.spyOn(sdkModule, "loadCliExtensionProviders").mockResolvedValue(undefined);
+	vi.spyOn(modelSelection, "resolvePrimaryModel").mockResolvedValue({
+		model: { name: "test-primary", provider: "test", id: "test" } as never,
+		apiKey: "test-key",
+	});
+	vi.spyOn(modelSelection, "resolveSmolModel").mockResolvedValue({
+		model: { name: "test-smol", provider: "test", id: "test" } as never,
+		apiKey: "test-key",
+		thinkingLevel: undefined,
+	});
+	return model;
+}
+
+async function setupRepoMocks() {
+	vi.spyOn(Settings, "init").mockResolvedValue(Settings.isolated());
+	vi.spyOn(sdkModule, "discoverAuthStorage").mockResolvedValue({
+		setFallbackResolver: () => {},
+	} as never);
+	vi.spyOn(sdkModule, "discoverContextFiles").mockResolvedValue([]);
+	vi.spyOn(gitModule.diff, "changedFiles").mockResolvedValue(["src/a.ts"]);
+	vi.spyOn(gitModule.diff, "numstat").mockResolvedValue(NUMSTAT);
+	vi.spyOn(gitModule, "commit").mockResolvedValue({ stdout: "", stderr: "", exitCode: 0 } as never);
+}
+
+afterEach(() => {
+	vi.restoreAllMocks();
+	delete process.env.PI_COMMIT_TEST_FALLBACK;
+});
+
+describe("runAgenticCommit fallback signalling (issue #7835)", () => {
+	it("reports usedFallback when the fallback commit path is forced", async () => {
+		mockModelResolution();
+		await setupRepoMocks();
+		process.env.PI_COMMIT_TEST_FALLBACK = "true";
+
+		const result = await runAgenticCommit({ noChangelog: true, push: false, dryRun: false });
+
+		expect(gitModule.commit).toHaveBeenCalledTimes(1);
+		expect(result).toEqual({ usedFallback: true });
+	});
+
+	it("reports usedFallback when the commit agent throws before completing", async () => {
+		mockModelResolution();
+		await setupRepoMocks();
+		vi.spyOn(agentModule, "runCommitAgentSession").mockRejectedValue(new Error("model unreachable"));
+
+		const result = await runAgenticCommit({ noChangelog: true, push: false, dryRun: false });
+
+		expect(gitModule.commit).toHaveBeenCalledTimes(1);
+		expect(result).toEqual({ usedFallback: true });
+	});
+
+	it("reports usedFallback when the agent completes without a proposal", async () => {
+		mockModelResolution();
+		await setupRepoMocks();
+		vi.spyOn(agentModule, "runCommitAgentSession").mockImplementation((async (input: never) => {
+			const { onComplete } = input as { onComplete: (state: never) => Promise<void> };
+			await onComplete({} as never);
+		}) as never);
+
+		const result = await runAgenticCommit({ noChangelog: true, push: false, dryRun: false });
+
+		expect(gitModule.commit).toHaveBeenCalledTimes(1);
+		expect(result).toEqual({ usedFallback: true });
+	});
+
+	it("reports a clean run when the agent produces a proposal", async () => {
+		mockModelResolution();
+		await setupRepoMocks();
+		vi.spyOn(agentModule, "runCommitAgentSession").mockImplementation((async (input: never) => {
+			const { onComplete } = input as { onComplete: (state: never) => Promise<void> };
+			await onComplete({
+				proposal: {
+					analysis: { type: "fix", scope: "test", details: [], issueRefs: [] },
+					summary: "fixed the thing",
+					warnings: [],
+				},
+			} as never);
+		}) as never);
+
+		const result = await runAgenticCommit({ noChangelog: true, push: false, dryRun: false });
+
+		expect(gitModule.commit).toHaveBeenCalledTimes(1);
+		expect(result).toEqual({ usedFallback: false });
+	});
+});