1 files changed, 95 insertions, 0 deletions
diff --git a/devtools/client/netmonitor/test/browser_net_column-resize-fit.js b/devtools/client/netmonitor/test/browser_net_column-resize-fit.js
new file mode 100644
index 0000000000..7cb60a8c38
--- /dev/null
+++ b/devtools/client/netmonitor/test/browser_net_column-resize-fit.js
@@ -0,0 +1,95 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/**
+ * Tests resizing of columns in NetMonitor.
+ */
+add_task(async function () {
+  // Reset visibleColumns so we only get the default ones
+  // and not all that are set in head.js
+  Services.prefs.clearUserPref("devtools.netmonitor.visibleColumns");
+  const visibleColumns = JSON.parse(
+    Services.prefs.getCharPref("devtools.netmonitor.visibleColumns")
+  );
+  // Init network monitor
+  const { monitor } = await initNetMonitor(SIMPLE_URL, {
+    requestCount: 1,
+  });
+  info("Starting test... ");
+
+  const { document } = monitor.panelWin;
+
+  // Wait for network events (to have some requests in the table)
+  const wait = waitForNetworkEvents(monitor, 1);
+  await reloadBrowser();
+  await wait;
+
+  info("Testing column resize to fit using double-click on draggable resizer");
+  const fileHeader = document.querySelector(`#requests-list-file-header-box`);
+  const fileColumnResizer = fileHeader.querySelector(".column-resizer");
+
+  EventUtils.sendMouseEvent({ type: "dblclick" }, fileColumnResizer);
+
+  // After resize - get fresh prefs for tests.
+  let columnsData = JSON.parse(
+    Services.prefs.getCharPref("devtools.netmonitor.columnsData")
+  );
+
+  // `File` column before resize: 25%, after resize: 11.25%
+  // `Transferred` column before resize: 10%, after resize: 10%
+  checkColumnsData(columnsData, "file", 12);
+  checkSumOfVisibleColumns(columnsData, visibleColumns);
+
+  info(
+    "Testing column resize to fit using context menu `Resize Column To Fit Content`"
+  );
+
+  // Resizing `transferred` column.
+  EventUtils.sendMouseEvent(
+    { type: "contextmenu" },
+    document.querySelector("#requests-list-transferred-button")
+  );
+
+  await selectContextMenuItem(
+    monitor,
+    "request-list-header-resize-column-to-fit-content"
+  );
+
+  columnsData = JSON.parse(
+    Services.prefs.getCharPref("devtools.netmonitor.columnsData")
+  );
+
+  // `Transferred` column before resize: 10%, after resize: 2.97%
+  checkColumnsData(columnsData, "transferred", 3);
+  checkSumOfVisibleColumns(columnsData, visibleColumns);
+
+  // Done: clean up.
+  return teardown(monitor);
+});
+
+function checkColumnsData(columnsData, column, expectedWidth) {
+  const width = getWidthFromPref(columnsData, column);
+  const widthsDiff = Math.abs(width - expectedWidth);
+  ok(
+    widthsDiff < 2,
+    `Column ${column} has expected size. Got ${width}, Expected ${expectedWidth}`
+  );
+}
+
+function checkSumOfVisibleColumns(columnsData, visibleColumns) {
+  let sum = 0;
+  visibleColumns.forEach(column => {
+    sum += getWidthFromPref(columnsData, column);
+  });
+  sum = Math.round(sum);
+  is(sum, 100, "All visible columns cover 100%.");
+}
+
+function getWidthFromPref(columnsData, column) {
+  const widthInPref = columnsData.find(function (element) {
+    return element.name === column;
+  }).width;
+  return widthInPref;
+}