fix(bash): delete pre-created snapshot file on creation failure

getOrCreateSnapshot in shell-snapshot.ts pre-creates snapshotPath as an empty temp file and returns null on spawn failure, timeout, or nonzero exit without deleting it, leaving stale files in os.tmpdir()/omp-shell-snapshots/. Track whether snapshot creation succeeded and remove the pre-created file in a finally block on every failure path using fs.rmSync(snapshotPath, { force: true }), with best-effort error suppression so cleanup failures never propagate. Verified with `bunx tsc --noEmit -p packages/coding-agent/tsconfig.json` and `bun test packages/coding-agent/test/shell-snapshot.test.ts` (22 pass).

Closes #4236

packages/coding-agent/CHANGELOG.md

@@ -2,6 +2,11 @@
 
 ## [Unreleased]
 
+### Fixed
+
+- Delete pre-created shell snapshot file when snapshot creation fails ([#4236](https://github.com/can1357/oh-my-pi/issues/4236))
+
+
 ## [16.3.0] - 2026-07-02
 
 ### Added

packages/coding-agent/src/utils/shell-snapshot.ts

@@ -260,6 +260,7 @@ export async function getOrCreateSnapshot(
 	// Generate and execute snapshot script
 	const script = generateSnapshotScript(shell, snapshotPath, rcFile);
 
+	let succeeded = false;
 	try {
 		const snapshotEnv = sanitizeSnapshotEnv(env);
 		const spawnEnv: Record<string, string> = {};
@@ -289,10 +290,19 @@ export async function getOrCreateSnapshot(
 			}
 			scrubSnapshotInPlace(snapshotPath);
 			cachedSnapshotPaths.set(cacheKey, snapshotPath);
+			succeeded = true;
 			return snapshotPath;
 		}
 	} catch {
 		// Snapshot creation failed, proceed without it
+	} finally {
+		if (!succeeded) {
+			try {
+				fs.rmSync(snapshotPath, { force: true });
+			} catch {
+				// best-effort cleanup; force: true ignores ENOENT
+			}
+		}
 	}
 
 	return null;

packages/coding-agent/test/shell-snapshot.test.ts

@@ -315,4 +315,81 @@ describe("getOrCreateSnapshot", () => {
 		const content = await fs.readFile(snapshotPath!, "utf8");
 		expect(content).toContain(`export __MISE_EXE='${REAL_ECHO}'`);
 	});
+	it("cleans up the empty snapshot file when the shell exits with a non-zero code", async () => {
+		const testRoot = await fs.mkdtemp(path.join(os.tmpdir(), "omp-snap-fail-"));
+		const originalTmpDir = process.env.TMPDIR;
+		process.env.TMPDIR = testRoot;
+		try {
+			const fakeShell = path.join(testRoot, "fail-shell.sh");
+			await fs.writeFile(fakeShell, `#!/bin/sh\nexit 1\n`);
+			await fs.chmod(fakeShell, 0o755);
+
+			const env = { ...process.env, HOME: testRoot };
+			const snapshotDir = path.join(testRoot, "omp-shell-snapshots");
+
+			const snapshotPath = await getOrCreateSnapshot(fakeShell, env);
+			expect(snapshotPath).toBeNull();
+
+			// Verify that no snapshot files were left behind in the isolated tmpdir
+			if (existsSync(snapshotDir)) {
+				const files = await fs.readdir(snapshotDir);
+				expect(files).toEqual([]);
+			}
+		} finally {
+			if (originalTmpDir === undefined) delete process.env.TMPDIR;
+			else process.env.TMPDIR = originalTmpDir;
+			await fs.rm(testRoot, { recursive: true, force: true });
+		}
+	});
+
+	it("cleans up the empty snapshot file when the shell fails to spawn", async () => {
+		const testRoot = await fs.mkdtemp(path.join(os.tmpdir(), "omp-snap-spawn-fail-"));
+		const originalTmpDir = process.env.TMPDIR;
+		process.env.TMPDIR = testRoot;
+		try {
+			const fakeShell = path.join(testRoot, "does-not-exist-shell");
+
+			const env = { ...process.env, HOME: testRoot };
+			const snapshotDir = path.join(testRoot, "omp-shell-snapshots");
+
+			const snapshotPath = await getOrCreateSnapshot(fakeShell, env);
+			expect(snapshotPath).toBeNull();
+
+			if (existsSync(snapshotDir)) {
+				const files = await fs.readdir(snapshotDir);
+				expect(files).toEqual([]);
+			}
+		} finally {
+			if (originalTmpDir === undefined) delete process.env.TMPDIR;
+			else process.env.TMPDIR = originalTmpDir;
+			await fs.rm(testRoot, { recursive: true, force: true });
+		}
+	});
+
+	it("cleans up the empty snapshot file when the shell execution times out", async () => {
+		const testRoot = await fs.mkdtemp(path.join(os.tmpdir(), "omp-snap-timeout-"));
+		const originalTmpDir = process.env.TMPDIR;
+		process.env.TMPDIR = testRoot;
+		try {
+			const fakeShell = path.join(testRoot, "timeout-shell.sh");
+			// Sleep longer than SNAPSHOT_TIMEOUT_MS (2000)
+			await fs.writeFile(fakeShell, `#!/bin/sh\nsleep 3\n`);
+			await fs.chmod(fakeShell, 0o755);
+
+			const env = { ...process.env, HOME: testRoot };
+			const snapshotDir = path.join(testRoot, "omp-shell-snapshots");
+
+			const snapshotPath = await getOrCreateSnapshot(fakeShell, env);
+			expect(snapshotPath).toBeNull();
+
+			if (existsSync(snapshotDir)) {
+				const files = await fs.readdir(snapshotDir);
+				expect(files).toEqual([]);
+			}
+		} finally {
+			if (originalTmpDir === undefined) delete process.env.TMPDIR;
+			else process.env.TMPDIR = originalTmpDir;
+			await fs.rm(testRoot, { recursive: true, force: true });
+		}
+	}, 5000); // increase test timeout to 5s to accommodate the 2s snapshot timeout
 });