added orai

24_12_09/node_modules/web-vitals/dist/modules/onFID.js

@@ -0,0 +1,70 @@
+/*
+ * 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 { onBFCacheRestore } from './lib/bfcache.js';
+import { bindReporter } from './lib/bindReporter.js';
+import { getVisibilityWatcher } from './lib/getVisibilityWatcher.js';
+import { initMetric } from './lib/initMetric.js';
+import { observe } from './lib/observe.js';
+import { onHidden } from './lib/onHidden.js';
+import { firstInputPolyfill, resetFirstInputPolyfill, } from './lib/polyfills/firstInputPolyfill.js';
+import { runOnce } from './lib/runOnce.js';
+import { whenActivated } from './lib/whenActivated.js';
+/** Thresholds for FID. See https://web.dev/articles/fid#what_is_a_good_fid_score */
+export const FIDThresholds = [100, 300];
+/**
+ * Calculates the [FID](https://web.dev/articles/fid) value for the current page and
+ * calls the `callback` function once the value is ready, along with the
+ * relevant `first-input` performance entry used to determine the value. The
+ * reported value is a `DOMHighResTimeStamp`.
+ *
+ * _**Important:** since FID is only reported after the user interacts with the
+ * page, it's possible that it will not be reported for some page loads._
+ */
+export const onFID = (onReport, opts) => {
+    // Set defaults
+    opts = opts || {};
+    whenActivated(() => {
+        const visibilityWatcher = getVisibilityWatcher();
+        let metric = initMetric('FID');
+        let report;
+        const handleEntry = (entry) => {
+            // Only report if the page wasn't hidden prior to the first input.
+            if (entry.startTime < visibilityWatcher.firstHiddenTime) {
+                metric.value = entry.processingStart - entry.startTime;
+                metric.entries.push(entry);
+                report(true);
+            }
+        };
+        const handleEntries = (entries) => {
+            entries.forEach(handleEntry);
+        };
+        const po = observe('first-input', handleEntries);
+        report = bindReporter(onReport, metric, FIDThresholds, opts.reportAllChanges);
+        if (po) {
+            onHidden(runOnce(() => {
+                handleEntries(po.takeRecords());
+                po.disconnect();
+            }));
+            onBFCacheRestore(() => {
+                metric = initMetric('FID');
+                report = bindReporter(onReport, metric, FIDThresholds, opts.reportAllChanges);
+                // Browsers don't re-emit FID on bfcache restore so fake it until you make it
+                resetFirstInputPolyfill();
+                firstInputPolyfill(handleEntry);
+            });
+        }
+    });
+};