1 files changed, 47 insertions, 0 deletions
diff --git a/devtools/client/webconsole/test/browser/browser_webconsole_loglimit.js b/devtools/client/webconsole/test/browser/browser_webconsole_loglimit.js
new file mode 100644
index 0000000000..ddb86a0a92
--- /dev/null
+++ b/devtools/client/webconsole/test/browser/browser_webconsole_loglimit.js
@@ -0,0 +1,47 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Test that messages are properly updated when the log limit is reached.
+
+const TEST_URI =
+  "data:text/html;charset=utf-8,Web Console test for " +
+  "Old messages are removed after passing devtools.hud.loglimit";
+
+add_task(async function() {
+  await pushPref("devtools.hud.loglimit", 140);
+  const hud = await openNewTabAndConsole(TEST_URI);
+  await clearOutput(hud);
+
+  let onMessage = waitForMessage(hud, "test message [149]");
+  SpecialPowers.spawn(gBrowser.selectedBrowser, [], async function() {
+    for (let i = 0; i < 150; i++) {
+      content.console.log(`test message [${i}]`);
+    }
+  });
+  await onMessage;
+
+  ok(!findMessage(hud, "test message [0]"), "Message 0 has been pruned");
+  ok(!findMessage(hud, "test message [9]"), "Message 9 has been pruned");
+  ok(findMessage(hud, "test message [10]"), "Message 10 is still displayed");
+  is(
+    findMessages(hud, "").length,
+    140,
+    "Number of displayed messages is correct"
+  );
+
+  onMessage = waitForMessage(hud, "hello world");
+  SpecialPowers.spawn(gBrowser.selectedBrowser, [], async function() {
+    content.console.log("hello world");
+  });
+  await onMessage;
+
+  ok(!findMessage(hud, "test message [10]"), "Message 10 has been pruned");
+  ok(findMessage(hud, "test message [11]"), "Message 11 is still displayed");
+  is(
+    findMessages(hud, "").length,
+    140,
+    "Number of displayed messages is still correct"
+  );
+});