1 files changed, 57 insertions, 0 deletions
diff --git a/devtools/server/tests/xpcshell/test_stepping-02.js b/devtools/server/tests/xpcshell/test_stepping-02.js
new file mode 100644
index 0000000000..c9df671839
--- /dev/null
+++ b/devtools/server/tests/xpcshell/test_stepping-02.js
@@ -0,0 +1,57 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/**
+ * Check basic step-in functionality.
+ */
+
+add_task(
+  threadFrontTest(async ({ threadFront, debuggee }) => {
+    dumpn("Evaluating test code and waiting for first debugger statement");
+    const dbgStmt = await executeOnNextTickAndWaitForPause(
+      () => evaluateTestCode(debuggee),
+      threadFront
+    );
+    equal(
+      dbgStmt.frame.where.line,
+      2,
+      "Should be at debugger statement on line 2"
+    );
+    equal(debuggee.a, undefined);
+    equal(debuggee.b, undefined);
+
+    const step1 = await stepIn(threadFront);
+    equal(step1.why.type, "resumeLimit");
+    equal(step1.frame.where.line, 3);
+    equal(debuggee.a, undefined);
+    equal(debuggee.b, undefined);
+
+    const step3 = await stepIn(threadFront);
+    equal(step3.why.type, "resumeLimit");
+    equal(step3.frame.where.line, 4);
+    equal(debuggee.a, 1);
+    equal(debuggee.b, undefined);
+
+    const step4 = await stepIn(threadFront);
+    equal(step4.why.type, "resumeLimit");
+    equal(step4.frame.where.line, 4);
+    equal(debuggee.a, 1);
+    equal(debuggee.b, 2);
+  })
+);
+
+function evaluateTestCode(debuggee) {
+  // prettier-ignore
+  Cu.evalInSandbox(
+    `                                   // 1
+    debugger;                           // 2
+    var a = 1;                          // 3
+    var b = 2;`,                        // 4
+    debuggee,
+    "1.8",
+    "test_stepping-01-test-code.js",
+    1
+  );
+}