Enable stepping into callback passed to builtins (e.g. Array.forEach).

test/mjsunit/debug-stepin-builtin-callback.js

Index: test/mjsunit/debug-stepin-builtin-callback.js
diff --git a/test/mjsunit/debug-stepin-builtin-callback.js b/test/mjsunit/debug-stepin-builtin-callback.js
new file mode 100644
index 0000000000000000000000000000000000000000..e9d5f7ba0a5f5bf5ced31f1642f87eb839f37199
--- /dev/null
+++ b/test/mjsunit/debug-stepin-builtin-callback.js
@@ -0,0 +1,206 @@
+// Copyright 2012 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Flags: --expose-debug-as debug
+
+// Test stepping into callbacks passed to builtin functions.
+
+Debug = debug.Debug
+
+var exception = false;
+
+function array_listener(event, exec_state, event_data, data) {
+  try {
+    if (event == Debug.DebugEvent.Break) {
+      if (breaks == 0) {
+        exec_state.prepareStep(Debug.StepAction.StepIn, 2);
+        breaks = 1;
+      } else if (breaks <= 3) {
+        breaks++;
+        // Check whether we break at the expected line.
+        print(event_data.sourceLineText());
+        assertTrue(event_data.sourceLineText().indexOf("Expected to step") > 0);
+        exec_state.prepareStep(Debug.StepAction.StepIn, 3);
+      }
+    }
+  } catch (e) {
+    exception = true;
+  }
+};
+
+function cb_false(num) {
+  print("element " + num);  // Expected to step to this point.
+  return false;
+}
+
+function cb_true(num) {
+  print("element " + num);  // Expected to step to this point.
+  return true;
+}
+
+function cb_reduce(a, b) {
+  print("elements " + a + " and " + b);  // Expected to step to this point.
+  return a + b;
+}
+
+var a = [1, 2, 3, 4];
+
+Debug.setListener(array_listener);
+
+var breaks = 0;
+debugger;
+a.forEach(cb_true);
+assertFalse(exception);
+assertEquals(4, breaks);
+
+breaks = 0;
+debugger;
+a.some(cb_false);
+assertFalse(exception);
+assertEquals(4, breaks);
+
+breaks = 0;
+debugger;
+a.every(cb_true);
+assertEquals(4, breaks);
+assertFalse(exception);
+
+breaks = 0;
+debugger;
+a.map(cb_true);
+assertFalse(exception);
+assertEquals(4, breaks);
+
+breaks = 0;
+debugger;
+a.filter(cb_true);
+assertFalse(exception);
+assertEquals(4, breaks);
+
+breaks = 0;
+debugger;
+a.reduce(cb_reduce);
+assertFalse(exception);
+assertEquals(4, breaks);
+
+breaks = 0;
+debugger;
+a.reduceRight(cb_reduce);
+assertFalse(exception);
+assertEquals(4, breaks);
+
+Debug.setListener(null);
+
+
+// Test two levels of builtin callbacks:
+// Array.forEach calls a callback function, which by itself uses
+// Array.forEach with another callback function.
+
+function second_level_listener(event, exec_state, event_data, data) {
+  try {
+    if (event == Debug.DebugEvent.Break) {
+      if (breaks == 0) {
+        exec_state.prepareStep(Debug.StepAction.StepIn, 3);
+        breaks = 1;
+      } else if (breaks <= 16) {
+        breaks++;
+        // Check whether we break at the expected line.
+        assertTrue(event_data.sourceLineText().indexOf("Expected to step") > 0);
+        // Step two steps further every four breaks to skip the
+        // forEach call in the first level of recurision.
+        var step = (breaks % 4 == 1) ? 6 : 3;
+        exec_state.prepareStep(Debug.StepAction.StepIn, step);
+      }
+    }
+  } catch (e) {
+    exception = true;
+  }
+};
+
+function cb_foreach(num) {
+  a.forEach(cb_true);
+  print("back to the first level of recursion.");
+}
+
+Debug.setListener(second_level_listener);
+
+breaks = 0;
+debugger;
+a.forEach(cb_foreach);
+assertFalse(exception);
+assertEquals(17, breaks);
+
+Debug.setListener(null);
+
+
+//Test replace callback in String.replace.
+
+function replace_listener(event, exec_state, event_data, data) {
+  try {
+    if (event == Debug.DebugEvent.Break) {
+      if (breaks == 0) {
+        exec_state.prepareStep(Debug.StepAction.StepIn, 2);
+        breaks = 1;
+      } else {
+       // Check whether we break at the expected line.
+       assertTrue(event_data.sourceLineText().indexOf("Expected to step") > 0);
+      }
+    }
+  } catch (e) {
+    exception = true;
+  }
+};
+
+function cb_replace(match) {
+  print("matching string: " + match);  // Expected to step to this point.
+  return "_";
+}
+
+var s = "abcdefgehijke";
+
+Debug.setListener(replace_listener);
+
+breaks = 0;
+debugger;
+assertEquals("ab_defgehijke", s.replace("c", cb_replace));
+assertFalse(exception);
+assertEquals(1, breaks);
+
+breaks = 0;
+debugger;
+assertEquals("abcdefgehij_", s.replace(/..$/, cb_replace));
+assertFalse(exception);
+assertEquals(1, breaks);
+
+breaks = 0;
+debugger;
+assertEquals("abcd_fg_hijk_", s.replace(/e/g, cb_replace));
+assertFalse(exception);
+assertEquals(1, breaks);
+
+
+Debug.setListener(null);