diff -r 000000000000 -r 6474c204b198 browser/devtools/debugger/test/browser_dbg_pretty-print-on-paused.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/devtools/debugger/test/browser_dbg_pretty-print-on-paused.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,67 @@
+/* Any copyright is dedicated to the Public Domain.
+  http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Test that pretty printing when the debugger is paused does not switch away
+ * from the selected source.
+ */
+
+const TAB_URL = EXAMPLE_URL + "doc_pretty-print-on-paused.html";
+
+let gTab, gDebuggee, gPanel, gDebugger, gThreadClient, gSources;
+
+const SECOND_SOURCE_VALUE = EXAMPLE_URL + "code_ugly-2.js";
+
+function test(){
+  initDebugger(TAB_URL).then(([aTab, aDebuggee, aPanel]) => {
+    gTab = aTab;
+    gDebuggee = aDebuggee;
+    gPanel = aPanel;
+    gDebugger = gPanel.panelWin;
+    gThreadClient = gDebugger.gThreadClient;
+    gSources = gDebugger.DebuggerView.Sources;
+
+    Task.spawn(function* () {
+      try {
+        yield ensureSourceIs(gPanel, "code_script-switching-02.js", true);
+
+        yield doInterrupt(gPanel);
+        yield rdpInvoke(gThreadClient, gThreadClient.setBreakpoint, {
+          url: gSources.selectedValue,
+          line: 6
+        });
+        yield doResume(gPanel);
+
+        const bpHit = waitForCaretAndScopes(gPanel, 6);
+        // Get the debuggee call off this tick so that we aren't accidentally
+        // blocking the yielding of bpHit which causes a deadlock.
+        executeSoon(() => gDebuggee.secondCall());
+        yield bpHit;
+
+        info("Switch to the second source.");
+        const sourceShown = waitForSourceShown(gPanel, SECOND_SOURCE_VALUE);
+        gSources.selectedValue = SECOND_SOURCE_VALUE;
+        yield sourceShown;
+
+        info("Pretty print the source.");
+        const prettyPrinted = waitForSourceShown(gPanel, SECOND_SOURCE_VALUE);
+        gDebugger.document.getElementById("pretty-print").click();
+        yield prettyPrinted;
+
+        yield resumeDebuggerThenCloseAndFinish(gPanel);
+      } catch (e) {
+        DevToolsUtils.reportException("browser_dbg_pretty-print-on-paused.js", e);
+        ok(false, "Got an error: " + DevToolsUtils.safeErrorString(e));
+      }
+    });
+  });
+}
+
+registerCleanupFunction(function() {
+  gTab = null;
+  gDebuggee = null;
+  gPanel = null;
+  gDebugger = null;
+  gThreadClient = null;
+  gSources = null;
+});