1 files changed, 42 insertions, 0 deletions
diff --git a/devtools/client/memory/reducers/allocations.js b/devtools/client/memory/reducers/allocations.js
new file mode 100644
index 000000000..ccb92f825
--- /dev/null
+++ b/devtools/client/memory/reducers/allocations.js
@@ -0,0 +1,42 @@
+/* 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/. */
+
+const { assert } = require("devtools/shared/DevToolsUtils");
+const { actions } = require("../constants");
+
+let handlers = Object.create(null);
+
+handlers[actions.TOGGLE_RECORD_ALLOCATION_STACKS_START] = function (state, action) {
+  assert(!state.togglingInProgress,
+         "Changing recording state must not be reentrant.");
+
+  return {
+    recording: !state.recording,
+    togglingInProgress: true,
+  };
+};
+
+handlers[actions.TOGGLE_RECORD_ALLOCATION_STACKS_END] = function (state, action) {
+  assert(state.togglingInProgress,
+         "Should not complete changing recording state if we weren't changing "
+         + "recording state already.");
+
+  return {
+    recording: state.recording,
+    togglingInProgress: false,
+  };
+};
+
+const DEFAULT_ALLOCATIONS_STATE = {
+  recording: false,
+  togglingInProgress: false
+};
+
+module.exports = function (state = DEFAULT_ALLOCATIONS_STATE, action) {
+  let handle = handlers[action.type];
+  if (handle) {
+    return handle(state, action);
+  }
+  return state;
+};