1 files changed, 30 insertions, 0 deletions
diff --git a/devtools/client/debugger/src/reducers/preview.js b/devtools/client/debugger/src/reducers/preview.js
new file mode 100644
index 0000000000..d7ee396bf5
--- /dev/null
+++ b/devtools/client/debugger/src/reducers/preview.js
@@ -0,0 +1,30 @@
+/* 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/>. */
+
+export function initialPreviewState() {
+  return {
+    preview: null,
+    previewCount: 0,
+  };
+}
+
+function update(state = initialPreviewState(), action) {
+  switch (action.type) {
+    case "CLEAR_PREVIEW": {
+      return { ...state, preview: null };
+    }
+
+    case "START_PREVIEW": {
+      return { ...state, previewCount: state.previewCount + 1 };
+    }
+
+    case "SET_PREVIEW": {
+      return { ...state, preview: action.value };
+    }
+  }
+
+  return state;
+}
+
+export default update;