diff -r 000000000000 -r 6474c204b198 toolkit/devtools/server/tests/unit/test_breakpoint-12.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/devtools/server/tests/unit/test_breakpoint-12.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,99 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Make sure that setting a breakpoint twice in a line without bytecodes works
+ * as expected.
+ */
+
+const NUM_BREAKPOINTS = 10;
+var gDebuggee;
+var gClient;
+var gThreadClient;
+var gPath = getFilePath('test_breakpoint-12.js');
+var gBpActor;
+var gCount = 1;
+
+function run_test()
+{
+  initTestDebuggerServer();
+  gDebuggee = addTestGlobal("test-stack");
+  gClient = new DebuggerClient(DebuggerServer.connectPipe());
+  gClient.connect(function () {
+    attachTestTabAndResume(gClient, "test-stack", function (aResponse, aTabClient, aThreadClient) {
+      gThreadClient = aThreadClient;
+      test_child_skip_breakpoint();
+    });
+  });
+  do_test_pending();
+}
+
+function test_child_skip_breakpoint()
+{
+  gThreadClient.addOneTimeListener("paused", function (aEvent, aPacket) {
+    let location = { url: gPath, line: gDebuggee.line0 + 3};
+    gThreadClient.setBreakpoint(location, function (aResponse, bpClient) {
+      // Check that the breakpoint has properly skipped forward one line.
+      do_check_eq(aResponse.actualLocation.url, location.url);
+      do_check_eq(aResponse.actualLocation.line, location.line + 1);
+      gBpActor = aResponse.actor;
+
+      // Set more breakpoints at the same location.
+      set_breakpoints(location);
+    });
+
+  });
+
+  gDebuggee.eval("var line0 = Error().lineNumber;\n" +
+                 "function foo() {\n" + // line0 + 1
+                 "  this.a = 1;\n" +    // line0 + 2
+                 "  // A comment.\n" +  // line0 + 3
+                 "  this.b = 2;\n" +    // line0 + 4
+                 "}\n" +                // line0 + 5
+                 "debugger;\n" +        // line0 + 6
+                 "foo();\n");           // line0 + 7
+}
+
+// Set many breakpoints at the same location.
+function set_breakpoints(location) {
+  do_check_neq(gCount, NUM_BREAKPOINTS);
+  gThreadClient.setBreakpoint(location, function (aResponse, bpClient) {
+    // Check that the breakpoint has properly skipped forward one line.
+    do_check_eq(aResponse.actualLocation.url, location.url);
+    do_check_eq(aResponse.actualLocation.line, location.line + 1);
+    // Check that the same breakpoint actor was returned.
+    do_check_eq(aResponse.actor, gBpActor);
+
+    if (++gCount < NUM_BREAKPOINTS) {
+      set_breakpoints(location);
+      return;
+    }
+
+    // After setting all the breakpoints, check that only one has effectively
+    // remained.
+    gThreadClient.addOneTimeListener("paused", function (aEvent, aPacket) {
+      // Check the return value.
+      do_check_eq(aPacket.type, "paused");
+      do_check_eq(aPacket.frame.where.url, gPath);
+      do_check_eq(aPacket.frame.where.line, location.line + 1);
+      do_check_eq(aPacket.why.type, "breakpoint");
+      do_check_eq(aPacket.why.actors[0], bpClient.actor);
+      // Check that the breakpoint worked.
+      do_check_eq(gDebuggee.a, 1);
+      do_check_eq(gDebuggee.b, undefined);
+
+      gThreadClient.addOneTimeListener("paused", function (aEvent, aPacket) {
+        // We don't expect any more pauses after the breakpoint was hit once.
+        do_check_true(false);
+      });
+      gThreadClient.resume(function () {
+        // Give any remaining breakpoints a chance to trigger.
+        do_timeout(1000, finishClient.bind(null, gClient));
+      });
+
+    });
+    // Continue until the breakpoint is hit.
+    gThreadClient.resume();
+  });
+
+}