pi config update

pi/.pi/agent/extensions/git-checkout-guard.ts

@@ -0,0 +1,99 @@
+/**
+ * Git Checkout Guard Extension
+ *
+ * Prevents models from using `git checkout` or `git restore` to silently
+ * discard uncommitted changes in files.
+ */
+
+import type { ExtensionAPI } from "@mariozechner/pi-coding-agent";
+import { isToolCallEventType } from "@mariozechner/pi-coding-agent";
+import { execSync } from "child_process";
+
+/**
+ * Parse file paths from a git checkout/restore command.
+ * Returns null if the command doesn't look like a file-restore operation.
+ */
+function parseFileRestoreArgs(command: string): string[] | null {
+	// Normalize whitespace
+	const cmd = command.trim().replace(/\s+/g, " ");
+
+	// Match: git checkout -- <files>
+	// Match: git checkout <ref> -- <files>
+	const checkoutDashDash = cmd.match(/\bgit\s+checkout\b.*?\s--\s+(.+)/);
+	if (checkoutDashDash) {
+		return checkoutDashDash[1].trim().split(/\s+/);
+	}
+
+	// Match: git restore [--staged] [--source=<ref>] <files>
+	// (git restore always operates on files)
+	const restore = cmd.match(/\bgit\s+restore\s+(.+)/);
+	if (restore) {
+		// Filter out flags like --staged, --source=..., --worktree, --patch
+		const args = restore[1].trim().split(/\s+/);
+		const files = args.filter((a) => !a.startsWith("-"));
+		return files.length > 0 ? files : null;
+	}
+
+	return null;
+}
+
+/**
+ * Check which of the given file paths have uncommitted changes (staged or unstaged).
+ * Returns the subset that are dirty.
+ */
+function getDirtyFiles(files: string[], cwd: string): string[] {
+	const dirty: string[] = [];
+	for (const file of files) {
+		try {
+			// --porcelain output is empty for clean files
+			const out = execSync(`git status --porcelain -- ${JSON.stringify(file)}`, {
+				cwd,
+				encoding: "utf8",
+				stdio: ["ignore", "pipe", "ignore"],
+			}).trim();
+			if (out.length > 0) {
+				dirty.push(file);
+			}
+		} catch {
+			// Not a git repo or other error — skip
+		}
+	}
+	return dirty;
+}
+
+export default function (pi: ExtensionAPI) {
+	pi.on("tool_call", async (event, ctx) => {
+		if (!isToolCallEventType("bash", event)) return undefined;
+
+		const command: string = event.input.command ?? "";
+		const files = parseFileRestoreArgs(command);
+		if (!files || files.length === 0) return undefined;
+
+		const cwd = process.cwd();
+		const dirty = getDirtyFiles(files, cwd);
+		if (dirty.length === 0) return undefined; // nothing to protect
+
+		const fileList = dirty.map((f) => `  • ${f}`).join("\n");
+
+		if (!ctx.hasUI) {
+			return {
+				block: true,
+				reason: `git-checkout-guard: the following files have uncommitted changes and cannot be silently reverted:\n${fileList}\nShow the diff to the user and ask for explicit confirmation first.`,
+			};
+		}
+
+		const choice = await ctx.ui.select(
+			`⚠️  git-checkout-guard\n\nThe command:\n  ${command}\n\nwould discard uncommitted changes in:\n${fileList}\n\nProceed?`,
+			["No, cancel (show diff instead)", "Yes, discard changes anyway"],
+		);
+
+		if (choice !== "Yes, discard changes anyway") {
+			return {
+				block: true,
+				reason: `Blocked by git-checkout-guard. Run \`git diff ${dirty.join(" ")}\` and review before discarding.`,
+			};
+		}
+
+		return undefined;
+	});
+}