chrome-devtools-frontend
Version:
Chrome DevTools UI
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text/typescript
// Copyright 2023 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import type * as SDK from '../../core/sdk/sdk.js';
import * as Formatter from '../formatter/formatter.js';
import * as TextUtils from '../text_utils/text_utils.js';
type ScopeTreeNode = Formatter.FormatterWorkerPool.ScopeTreeNode;
/** If a script failed to parse, we stash null in order to prevent unnecessary re-parsing */
const scopeTrees = new WeakMap<SDK.Script.Script, Promise<ScopeTreeNode|null>>();
/**
* Computes and caches the scope tree for `script`.
*
* We use {@link SDK.Script.Script} as a key to uniquely identify scripts.
* {@link SDK.Script.Script} boils down to "target" + "script ID". This
* duplicates work in case of identitical script running on multiple targets
* (e.g. workers).
*/
export function scopeTreeForScript(script: SDK.Script.Script): Promise<ScopeTreeNode|null> {
let promise = scopeTrees.get(script);
if (promise === undefined) {
promise = script.requestContentData().then(content => {
if (TextUtils.ContentData.ContentData.isError(content)) {
return null;
}
const sourceType = script.isModule ? 'module' : 'script';
return Formatter.FormatterWorkerPool.formatterWorkerPool()
.javaScriptScopeTree(content.text, sourceType)
.catch(() => null);
});
scopeTrees.set(script, promise);
}
// We intentionally return `null` here if the script already failed to parse once.
return promise;
}