1 files changed, 81 insertions, 0 deletions
diff --git a/js/trace_test.ts b/js/trace_test.ts
new file mode 100644
index 000000000..ac83c1064
--- /dev/null
+++ b/js/trace_test.ts
@@ -0,0 +1,81 @@
+import { testPerm, assertEqual } from "./test_util.ts";
+import * as deno from "deno";
+
+testPerm({ write: true }, async function traceFunctionSuccess() {
+  const op = await deno.trace(async () => {
+    const enc = new TextEncoder();
+    const data = enc.encode("Hello");
+    // Mixing sync and async calls
+    const filename = deno.makeTempDirSync() + "/test.txt";
+    await deno.writeFile(filename, data, 0o666);
+    await deno.removeSync(filename);
+  });
+  assertEqual(op.length, 3);
+  assertEqual(op[0], { sync: true, name: "MakeTempDir" });
+  assertEqual(op[1], { sync: false, name: "WriteFile" });
+  assertEqual(op[2], { sync: true, name: "Remove" });
+});
+
+testPerm({ write: true }, async function tracePromiseSuccess() {
+  // Ensure we don't miss any send actions
+  // (new Promise(fn), fn runs synchronously)
+  const asyncFunction = async () => {
+    const enc = new TextEncoder();
+    const data = enc.encode("Hello");
+    // Mixing sync and async calls
+    const filename = deno.makeTempDirSync() + "/test.txt";
+    await deno.writeFile(filename, data, 0o666);
+    await deno.removeSync(filename);
+  };
+  const promise = Promise.resolve().then(asyncFunction);
+  const op = await deno.trace(promise);
+  assertEqual(op.length, 3);
+  assertEqual(op[0], { sync: true, name: "MakeTempDir" });
+  assertEqual(op[1], { sync: false, name: "WriteFile" });
+  assertEqual(op[2], { sync: true, name: "Remove" });
+});
+
+testPerm({ write: true }, async function traceRepeatSuccess() {
+  const op1 = await deno.trace(async () => await deno.makeTempDir());
+  assertEqual(op1.length, 1);
+  assertEqual(op1[0], { sync: false, name: "MakeTempDir" });
+  const op2 = await deno.trace(async () => await deno.statSync("."));
+  assertEqual(op2.length, 1);
+  assertEqual(op2[0], { sync: true, name: "Stat" });
+});
+
+testPerm({ write: true }, async function traceIdempotence() {
+  let op1, op2, op3;
+  op1 = await deno.trace(async () => {
+    const filename = (await deno.makeTempDir()) + "/test.txt";
+    op2 = await deno.trace(async () => {
+      const enc = new TextEncoder();
+      const data = enc.encode("Hello");
+      deno.writeFileSync(filename, data, 0o666);
+      op3 = await deno.trace(async () => {
+        await deno.remove(filename);
+      });
+      await deno.makeTempDir();
+    });
+  });
+
+  // Flatten the calls
+  assertEqual(op1.length, 4);
+  assertEqual(op1[0], { sync: false, name: "MakeTempDir" });
+  assertEqual(op1[1], { sync: true, name: "WriteFile" });
+  assertEqual(op1[2], { sync: false, name: "Remove" });
+  assertEqual(op1[3], { sync: false, name: "MakeTempDir" });
+
+  assertEqual(op2.length, 3);
+  assertEqual(op2[0], { sync: true, name: "WriteFile" });
+  assertEqual(op2[1], { sync: false, name: "Remove" });
+  assertEqual(op2[2], { sync: false, name: "MakeTempDir" });
+
+  assertEqual(op3.length, 1);
+  assertEqual(op3[0], { sync: false, name: "Remove" });
+
+  // Expect top-level repeat still works after all the nestings
+  const op4 = await deno.trace(async () => await deno.statSync("."));
+  assertEqual(op4.length, 1);
+  assertEqual(op4[0], { sync: true, name: "Stat" });
+});