1 files changed, 59 insertions, 0 deletions
diff --git a/devtools/client/debugger/src/selectors/pause.js b/devtools/client/debugger/src/selectors/pause.js
new file mode 100644
index 0000000000..fa87fcc36e
--- /dev/null
+++ b/devtools/client/debugger/src/selectors/pause.js
@@ -0,0 +1,59 @@
+// @flow
+/* 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 { getCurrentThread } from "../reducers/pause";
+import { getSelectedLocation } from "../reducers/sources";
+
+// eslint-disable-next-line
+import { getSelectedLocation as _getSelectedLocation } from "../utils/selected-location";
+import { createSelector } from "reselect";
+
+import type { Frame, SourceLocation, ThreadId } from "../types";
+import type { Selector, State } from "../reducers/types";
+
+export const getSelectedFrames: Selector<{ [string]: ?Frame }> = createSelector(
+  state => state.pause.threads,
+  threadPauseState => {
+    const selectedFrames = {};
+    for (const thread in threadPauseState) {
+      const pausedThread = threadPauseState[thread];
+      const { selectedFrameId, frames } = pausedThread;
+      if (frames) {
+        selectedFrames[thread] = frames.find(
+          frame => frame.id == selectedFrameId
+        );
+      }
+    }
+    return selectedFrames;
+  }
+);
+
+export function getSelectedFrame(state: State, thread: ThreadId): ?Frame {
+  const selectedFrames = getSelectedFrames(state);
+  return selectedFrames[thread];
+}
+
+export const getVisibleSelectedFrame: Selector<?{
+  id: string,
+  location: SourceLocation,
+}> = createSelector(
+  getSelectedLocation,
+  getSelectedFrames,
+  getCurrentThread,
+  (selectedLocation, selectedFrames, thread) => {
+    const selectedFrame = selectedFrames[thread];
+    if (!selectedFrame) {
+      return null;
+    }
+
+    const { id, displayName } = selectedFrame;
+
+    return {
+      id,
+      displayName,
+      location: _getSelectedLocation(selectedFrame, selectedLocation),
+    };
+  }
+);