Initial Commit

node_modules/web-vitals/dist/modules/lib/initMetric.js

@@ -0,0 +1,48 @@
+/*
+ * Copyright 2020 Google LLC
+ *
+ * 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
+ *
+ *     https://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 { getBFCacheRestoreTime } from './bfcache.js';
+import { generateUniqueID } from './generateUniqueID.js';
+import { getActivationStart } from './getActivationStart.js';
+import { getNavigationEntry } from './getNavigationEntry.js';
+export const initMetric = (name, value) => {
+    const navEntry = getNavigationEntry();
+    let navigationType = 'navigate';
+    if (getBFCacheRestoreTime() >= 0) {
+        navigationType = 'back-forward-cache';
+    }
+    else if (navEntry) {
+        if (document.prerendering || getActivationStart() > 0) {
+            navigationType = 'prerender';
+        }
+        else if (document.wasDiscarded) {
+            navigationType = 'restore';
+        }
+        else if (navEntry.type) {
+            navigationType = navEntry.type.replace(/_/g, '-');
+        }
+    }
+    // Use `entries` type specific for the metric.
+    const entries = [];
+    return {
+        name,
+        value: typeof value === 'undefined' ? -1 : value,
+        rating: 'good', // If needed, will be updated when reported. `const` to keep the type from widening to `string`.
+        delta: 0,
+        entries,
+        id: generateUniqueID(),
+        navigationType,
+    };
+};