1 files changed, 41 insertions, 0 deletions
diff --git a/packages/idb-bridge/src/util/normalizeKeyPath.ts b/packages/idb-bridge/src/util/normalizeKeyPath.ts
new file mode 100644
index 000000000..4e194b2d1
--- /dev/null
+++ b/packages/idb-bridge/src/util/normalizeKeyPath.ts
@@ -0,0 +1,41 @@
+/*
+ Copyright 2017 Jeremy Scheff
+ Copyright 2019 Florian Dold
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ or implied. See the License for the specific language governing
+ permissions and limitations under the License.
+*/
+
+import { IDBKeyPath } from "../idbtypes";
+
+export function normalizeKeyPath(
+  keyPath: IDBKeyPath | IDBKeyPath[],
+): string | string[] {
+  if (Array.isArray(keyPath)) {
+    const path: string[] = [];
+    for (let item of keyPath) {
+      // This doesn't make sense to me based on the spec, but it is needed to pass the W3C KeyPath tests (see same
+      // comment in validateKeyPath)
+      if (
+        item !== undefined &&
+        item !== null &&
+        typeof item !== "string" &&
+        (item as any).toString
+      ) {
+        item = (item as any).toString();
+      }
+      path.push(item);
+    }
+    return path;
+  }
+  return keyPath;
+}