1 files changed, 56 insertions, 0 deletions
diff --git a/devtools/client/debugger/src/selectors/threads.js b/devtools/client/debugger/src/selectors/threads.js
new file mode 100644
index 0000000000..8e3054ce7a
--- /dev/null
+++ b/devtools/client/debugger/src/selectors/threads.js
@@ -0,0 +1,56 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at <http://mozilla.org/MPL/2.0/>. */
+
+import { createSelector } from "reselect";
+import { parse } from "../utils/url";
+
+export const getThreads = createSelector(
+  state => state.threads.threads,
+  threads => threads.filter(thread => !isMainThread(thread))
+);
+
+export const getAllThreads = createSelector(
+  getMainThread,
+  getThreads,
+  (mainThread, threads) => {
+    const orderedThreads = Array.from(threads).sort((threadA, threadB) => {
+      if (threadA.name === threadB.name) {
+        return 0;
+      }
+      return threadA.name < threadB.name ? -1 : 1;
+    });
+    return [mainThread, ...orderedThreads].filter(Boolean);
+  }
+);
+
+function isMainThread(thread) {
+  return thread.isTopLevel;
+}
+
+export function getMainThread(state) {
+  return state.threads.threads.find(isMainThread);
+}
+
+/*
+ * Gets domain from the main thread url (without www prefix)
+ */
+export function getMainThreadHost(state) {
+  const url = getMainThread(state)?.url;
+  if (!url) {
+    return null;
+  }
+  const { host } = parse(url);
+  if (!host) {
+    return null;
+  }
+  return host.startsWith("www.") ? host.substring("www.".length) : host;
+}
+
+export function getThread(state, threadActor) {
+  return getAllThreads(state).find(thread => thread.actor === threadActor);
+}
+
+export function getIsThreadCurrentlyTracing(state, thread) {
+  return state.threads.mutableTracingThreads.has(thread);
+}