Fall back to isogit store when git is absent

Harbor and minimal containers have no git binary; the optimized
wrapper shells out via Bun.spawn and fails the first cycle commit.

Author: TheGreatAxios

src/session/optimized-context-store.test.ts

@@ -1,4 +1,4 @@
-import { describe, test, expect } from "bun:test";
+import { afterEach, describe, expect, spyOn, test } from "bun:test";
 import fs from "node:fs";
 import os from "node:os";
 import path from "node:path";
@@ -446,3 +446,68 @@ describe("createOptimizedContextStore checkpoint", () => {
     expect(atHead).toHaveLength(total);
   }, 20_000);
 });
+
+describe("createOptimizedContextStore without native git", () => {
+  const originalWhich = Bun.which.bind(Bun);
+  let whichSpy: ReturnType<typeof spyOn> | undefined;
+  let spawnSpy: ReturnType<typeof spyOn> | undefined;
+
+  afterEach(() => {
+    whichSpy?.mockRestore();
+    spawnSpy?.mockRestore();
+    whichSpy = undefined;
+    spawnSpy = undefined;
+  });
+
+  test("returns the base isogit store and commits without spawning git", async () => {
+    whichSpy = spyOn(Bun, "which").mockImplementation((cmd: string) => {
+      if (cmd === "git") return null;
+      return originalWhich(cmd);
+    });
+    spawnSpy = spyOn(Bun, "spawn");
+
+    const dir = tempDir();
+    const store = await createOptimizedContextStore(dir);
+
+    await store.writeTurns([turn("no-git")]);
+    await store.writeMetadata({
+      pendingOperations: [],
+      tokenUsage: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0, thinking: 0 },
+    });
+    const commit = await store.commit({ message: "isogit fallback" });
+
+    expect(commit.hash.length).toBeGreaterThan(0);
+    expect(commit.message).toBe("isogit fallback");
+
+    const loaded = await store.load();
+    expect(loaded.turns).toHaveLength(1);
+    expect((loaded.turns[0]!.content[0] as { text: string }).text).toBe("no-git");
+
+    const gitSpawns = spawnSpy.mock.calls.filter((call: unknown[]) => {
+      const argv = call[0];
+      return Array.isArray(argv) && argv[0] === "git";
+    });
+    expect(gitSpawns).toHaveLength(0);
+  });
+
+  test("still wraps with native git when git is on PATH", async () => {
+    expect(originalWhich("git")).not.toBeNull();
+
+    const dir = tempDir();
+    const store = await createOptimizedContextStore(dir);
+    spawnSpy = spyOn(Bun, "spawn");
+
+    await store.writeTurns([turn("with-git")]);
+    await store.writeMetadata({
+      pendingOperations: [],
+      tokenUsage: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0, thinking: 0 },
+    });
+    await store.commit({ message: "native path" });
+
+    const gitSpawns = spawnSpy.mock.calls.filter((call: unknown[]) => {
+      const argv = call[0];
+      return Array.isArray(argv) && argv[0] === "git";
+    });
+    expect(gitSpawns.length).toBeGreaterThan(0);
+  });
+});

src/session/optimized-context-store.ts

@@ -361,8 +361,15 @@ async function reconcileSegmentStaging(
  * work per reactor checkpoint. Turns and prompt snapshots are written as rolling
  * segment files so `git add` re-hashes only the small active segment, and only
  * spilled tool-output blobs that are new since the last commit are staged.
+ *
+ * When native `git` is missing from PATH (Harbor / minimal containers), skip the
+ * wrapper and return the base isomorphic-git store — its commit path never shells out.
  */
 export async function createOptimizedContextStore(dir: string): Promise<ContextStore> {
+  if (Bun.which("git") === null) {
+    return await createIsogitStore(dir);
+  }
+
   const base = await createIsogitStore(dir);
   const pendingBlobFilepaths = new Set<string>();
   const pendingSegmentPaths = new Set<string>();