1 files changed, 84 insertions, 0 deletions
diff --git a/devtools/client/memory/reducers/individuals.js b/devtools/client/memory/reducers/individuals.js
new file mode 100644
index 0000000000..9b5a2c89a5
--- /dev/null
+++ b/devtools/client/memory/reducers/individuals.js
@@ -0,0 +1,84 @@
+/* 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/. */
+"use strict";
+
+const {
+  assert,
+  immutableUpdate,
+} = require("resource://devtools/shared/DevToolsUtils.js");
+const {
+  actions,
+  individualsState,
+  viewState,
+} = require("resource://devtools/client/memory/constants.js");
+
+const handlers = Object.create(null);
+
+handlers[actions.POP_VIEW] = function (_state, _action) {
+  return null;
+};
+
+handlers[actions.CHANGE_VIEW] = function (individuals, { newViewState }) {
+  if (newViewState === viewState.INDIVIDUALS) {
+    assert(
+      !individuals,
+      "Should not switch to individuals view when already in individuals view"
+    );
+    return Object.freeze({
+      state: individualsState.COMPUTING_DOMINATOR_TREE,
+    });
+  }
+
+  return null;
+};
+
+handlers[actions.FOCUS_INDIVIDUAL] = function (individuals, { node }) {
+  assert(individuals, "Should have individuals");
+  return immutableUpdate(individuals, { focused: node });
+};
+
+handlers[actions.FETCH_INDIVIDUALS_START] = function (individuals, action) {
+  assert(individuals, "Should have individuals");
+  return Object.freeze({
+    state: individualsState.FETCHING,
+    focused: individuals.focused,
+  });
+};
+
+handlers[actions.FETCH_INDIVIDUALS_END] = function (individuals, action) {
+  assert(individuals, "Should have individuals");
+  assert(!individuals.nodes, "Should not have nodes");
+  assert(
+    individuals.state === individualsState.FETCHING,
+    "Should only end fetching individuals after starting."
+  );
+
+  const focused = individuals.focused
+    ? action.nodes.find(n => n.nodeId === individuals.focused.nodeId)
+    : null;
+
+  return Object.freeze({
+    state: individualsState.FETCHED,
+    nodes: action.nodes,
+    id: action.id,
+    censusBreakdown: action.censusBreakdown,
+    indices: action.indices,
+    labelDisplay: action.labelDisplay,
+    focused,
+    dominatorTree: action.dominatorTree,
+  });
+};
+
+handlers[actions.INDIVIDUALS_ERROR] = function (_, { error }) {
+  return Object.freeze({
+    error,
+    nodes: null,
+    state: individualsState.ERROR,
+  });
+};
+
+module.exports = function (individuals = null, action) {
+  const handler = handlers[action.type];
+  return handler ? handler(individuals, action) : individuals;
+};