1 files changed, 95 insertions, 0 deletions
diff --git a/devtools/server/tests/xpcshell/test_stepping-01.js b/devtools/server/tests/xpcshell/test_stepping-01.js
new file mode 100644
index 0000000000..20b866e9bb
--- /dev/null
+++ b/devtools/server/tests/xpcshell/test_stepping-01.js
@@ -0,0 +1,95 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+/* eslint-disable no-shadow, max-nested-callbacks */
+
+"use strict";
+
+/**
+ * Check scenarios where we're leaving function a and
+ * going to the function b's call-site.
+ */
+
+async function testFinish({ threadFront, devToolsClient }) {
+  await close(devToolsClient);
+
+  do_test_finished();
+}
+
+async function invokeAndPause({ global, threadFront }, expression) {
+  return executeOnNextTickAndWaitForPause(
+    () => Cu.evalInSandbox(expression, global),
+    threadFront
+  );
+}
+
+async function step(threadFront, cmd) {
+  return cmd(threadFront);
+}
+
+function getPauseLocation(packet) {
+  const { line, column } = packet.frame.where;
+  return { line, column };
+}
+
+function getPauseReturn(packet) {
+  return packet.why.frameFinished.return;
+}
+
+async function steps(threadFront, sequence) {
+  const locations = [];
+  for (const cmd of sequence) {
+    const packet = await step(threadFront, cmd);
+    locations.push(getPauseLocation(packet));
+  }
+  return locations;
+}
+
+async function stepOutOfA(dbg, func, expectedLocation) {
+  await invokeAndPause(dbg, `${func}()`);
+  const { threadFront } = dbg;
+  await steps(threadFront, [stepOver, stepIn]);
+
+  const packet = await stepOut(threadFront);
+
+  deepEqual(
+    getPauseLocation(packet),
+    expectedLocation,
+    `step out location in ${func}`
+  );
+
+  await threadFront.resume();
+}
+
+async function stepOverInA(dbg, func, expectedLocation) {
+  await invokeAndPause(dbg, `${func}()`);
+  const { threadFront } = dbg;
+  await steps(threadFront, [stepOver, stepIn]);
+
+  let packet = await stepOver(threadFront);
+  equal(getPauseReturn(packet).ownPropertyLength, 1, "a() is returning obj");
+
+  packet = await stepOver(threadFront);
+  deepEqual(
+    getPauseLocation(packet),
+    expectedLocation,
+    `step out location in ${func}`
+  );
+  await dbg.threadFront.resume();
+}
+
+async function testStep(dbg, func, expectedValue) {
+  await stepOverInA(dbg, func, expectedValue);
+  await stepOutOfA(dbg, func, expectedValue);
+}
+
+function run_test() {
+  return (async function() {
+    const dbg = await setupTestFromUrl("stepping.js");
+
+    await testStep(dbg, "arithmetic", { line: 16, column: 8 });
+    await testStep(dbg, "composition", { line: 21, column: 3 });
+    await testStep(dbg, "chaining", { line: 26, column: 6 });
+
+    await testFinish(dbg);
+  })();
+}