1 files changed, 64 insertions, 0 deletions
diff --git a/devtools/client/netmonitor/test/browser_net_columns_last_column.js b/devtools/client/netmonitor/test/browser_net_columns_last_column.js
new file mode 100644
index 0000000000..aaed0aa210
--- /dev/null
+++ b/devtools/client/netmonitor/test/browser_net_columns_last_column.js
@@ -0,0 +1,64 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/**
+ * Tests that last visible column can't be hidden. Note that the column
+ * header is visible only if there are requests in the list.
+ */
+
+add_task(async function () {
+  const { monitor } = await initNetMonitor(SIMPLE_URL, {
+    requestCount: 1,
+  });
+  info("Starting test... ");
+
+  const { document, store, windowRequire } = monitor.panelWin;
+  const Actions = windowRequire("devtools/client/netmonitor/src/actions/index");
+  store.dispatch(Actions.batchEnable(false));
+
+  const wait = waitForNetworkEvents(monitor, 1);
+  await reloadBrowser();
+  await wait;
+
+  const initialColumns = store.getState().ui.columns;
+  for (const column in initialColumns) {
+    const shown = initialColumns[column];
+
+    const columns = store.getState().ui.columns;
+    const visibleColumns = [];
+    for (const c in columns) {
+      if (columns[c]) {
+        visibleColumns.push(c);
+      }
+    }
+
+    if (visibleColumns.length === 1) {
+      if (!shown) {
+        continue;
+      }
+      await testLastMenuItem(column);
+      break;
+    }
+
+    if (shown) {
+      await hideColumn(monitor, column);
+    }
+  }
+
+  await teardown(monitor);
+
+  async function testLastMenuItem(column) {
+    EventUtils.sendMouseEvent(
+      { type: "contextmenu" },
+      document.querySelector(`#requests-list-${column}-button`)
+    );
+
+    const menuItem = getContextMenuItem(
+      monitor,
+      `request-list-header-${column}-toggle`
+    );
+    ok(menuItem.disabled, "Last visible column menu item should be disabled.");
+  }
+});