feat: add apply_patch tool (exec-gated)

src/agents/apply-patch.test.ts

@@ -0,0 +1,74 @@
+import fs from "node:fs/promises";
+import os from "node:os";
+import path from "node:path";
+import { describe, expect, it } from "vitest";
+
+import { applyPatch } from "./apply-patch.js";
+
+async function withTempDir<T>(fn: (dir: string) => Promise<T>) {
+  const dir = await fs.mkdtemp(path.join(os.tmpdir(), "clawdbot-patch-"));
+  try {
+    return await fn(dir);
+  } finally {
+    await fs.rm(dir, { recursive: true, force: true });
+  }
+}
+
+describe("applyPatch", () => {
+  it("adds a file", async () => {
+    await withTempDir(async (dir) => {
+      const patch = `*** Begin Patch
+*** Add File: hello.txt
++hello
+*** End Patch`;
+
+      const result = await applyPatch(patch, { cwd: dir });
+      const contents = await fs.readFile(path.join(dir, "hello.txt"), "utf8");
+
+      expect(contents).toBe("hello\n");
+      expect(result.summary.added).toEqual(["hello.txt"]);
+    });
+  });
+
+  it("updates and moves a file", async () => {
+    await withTempDir(async (dir) => {
+      const source = path.join(dir, "source.txt");
+      await fs.writeFile(source, "foo\nbar\n", "utf8");
+
+      const patch = `*** Begin Patch
+*** Update File: source.txt
+*** Move to: dest.txt
+@@
+ foo
+-bar
++baz
+*** End Patch`;
+
+      const result = await applyPatch(patch, { cwd: dir });
+      const dest = path.join(dir, "dest.txt");
+      const contents = await fs.readFile(dest, "utf8");
+
+      expect(contents).toBe("foo\nbaz\n");
+      await expect(fs.stat(source)).rejects.toBeDefined();
+      expect(result.summary.modified).toEqual(["dest.txt"]);
+    });
+  });
+
+  it("supports end-of-file inserts", async () => {
+    await withTempDir(async (dir) => {
+      const target = path.join(dir, "end.txt");
+      await fs.writeFile(target, "line1\n", "utf8");
+
+      const patch = `*** Begin Patch
+*** Update File: end.txt
+@@
++line2
+*** End of File
+*** End Patch`;
+
+      await applyPatch(patch, { cwd: dir });
+      const contents = await fs.readFile(target, "utf8");
+      expect(contents).toBe("line1\nline2\n");
+    });
+  });
+});