fix(canvas): guard A2UI asset copy roots

vincentkoc · vincentkoc · commit e20edd753bd7 · 2026-06-22T16:43:08.000+08:00
diff --git a/extensions/canvas/scripts/copy-a2ui.mjs b/extensions/canvas/scripts/copy-a2ui.mjs
@@ -20,8 +20,27 @@ function shouldSkipMissingA2uiAssets(env = process.env) {
   return env.OPENCLAW_A2UI_SKIP_MISSING === "1" || Boolean(env.OPENCLAW_SPARSE_PROFILE);
 }
 
+function isRelativeWithin(relPath) {
+  return (
+    relPath === "" ||
+    (relPath !== ".." && !relPath.startsWith(`..${path.sep}`) && !path.isAbsolute(relPath))
+  );
+}
+
+function pathsOverlap(leftDir, rightDir) {
+  const left = path.resolve(leftDir);
+  const right = path.resolve(rightDir);
+  return (
+    isRelativeWithin(path.relative(left, right)) || isRelativeWithin(path.relative(right, left))
+  );
+}
+
 /** Copies A2UI assets, optionally tolerating missing bundles in sparse builds. */
 export async function copyA2uiAssets({ srcDir, outDir }) {
+  if (pathsOverlap(srcDir, outDir)) {
+    throw new Error("A2UI source and output directories must not overlap.");
+  }
+
   const skipMissing = shouldSkipMissingA2uiAssets(process.env);
   try {
     await fs.stat(path.join(srcDir, "index.html"));
diff --git a/extensions/canvas/scripts/copy-a2ui.test.ts b/extensions/canvas/scripts/copy-a2ui.test.ts
@@ -37,17 +37,17 @@ describe("canvas a2ui copy", () => {
 
   it("throws a helpful error when assets are missing", async () => {
     await withA2uiFixture(async (dir) => {
-      await expect(copyA2uiAssets({ srcDir: dir, outDir: path.join(dir, "out") })).rejects.toThrow(
-        'Run "pnpm canvas:a2ui:bundle"',
-      );
+      await expect(
+        copyA2uiAssets({ srcDir: path.join(dir, "src"), outDir: path.join(dir, "out") }),
+      ).rejects.toThrow('Run "pnpm canvas:a2ui:bundle"');
     });
   });
 
   it("skips missing assets when OPENCLAW_A2UI_SKIP_MISSING=1", async () => {
     await withA2uiFixture(async (dir) => {
       process.env.OPENCLAW_A2UI_SKIP_MISSING = "1";
       await expect(
-        copyA2uiAssets({ srcDir: dir, outDir: path.join(dir, "out") }),
+        copyA2uiAssets({ srcDir: path.join(dir, "src"), outDir: path.join(dir, "out") }),
       ).resolves.toBeUndefined();
     });
   });
@@ -56,7 +56,7 @@ describe("canvas a2ui copy", () => {
     await withA2uiFixture(async (dir) => {
       process.env.OPENCLAW_SPARSE_PROFILE = "core";
       await expect(
-        copyA2uiAssets({ srcDir: dir, outDir: path.join(dir, "out") }),
+        copyA2uiAssets({ srcDir: path.join(dir, "src"), outDir: path.join(dir, "out") }),
       ).resolves.toBeUndefined();
     });
   });
@@ -102,4 +102,21 @@ describe("canvas a2ui copy", () => {
       });
     });
   });
+
+  it("rejects overlapping source and output directories before cleaning output", async () => {
+    await withA2uiFixture(async (dir) => {
+      const srcDir = path.join(dir, "src");
+      await fs.mkdir(srcDir, { recursive: true });
+      await fs.writeFile(path.join(srcDir, "index.html"), "<html></html>", "utf8");
+      await fs.writeFile(path.join(srcDir, "a2ui.bundle.js"), "console.log(1);", "utf8");
+
+      await expect(copyA2uiAssets({ srcDir, outDir: srcDir })).rejects.toThrow("must not overlap");
+      await expect(fs.readFile(path.join(srcDir, "index.html"), "utf8")).resolves.toBe(
+        "<html></html>",
+      );
+      await expect(copyA2uiAssets({ srcDir, outDir: path.join(srcDir, "dist") })).rejects.toThrow(
+        "must not overlap",
+      );
+    });
+  });
 });
