front_end/third_party/source-map-scopes-codec/package/src/builder/builder.js

// Copyright 2025 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.
/**
 * Small utility class to build scope and range trees.
 *
 * This class allows construction of scope/range trees that will be rejected by the encoder.
 * Use this class if you guarantee proper nesting yourself and don't want to pay for the
 * checks, otherwise use the `SafeScopeInfoBuilder`.
 *
 * This class will also silently ignore calls that would fail otherwise. E.g. calling
 * `end*` without a matching `start*`.
 */ export class ScopeInfoBuilder {
  #scopes = [];
  #ranges = [];
  #scopeStack = [];
  #rangeStack = [];
  #knownScopes = new Set();
  #keyToScope = new Map();
  #lastScope = null;
  addNullScope() {
    this.#scopes.push(null);
    return this;
  }
  startScope(line, column, options) {
    const scope = {
      start: {
        line,
        column
      },
      end: {
        line,
        column
      },
      variables: options?.variables?.slice(0) ?? [],
      children: [],
      isStackFrame: Boolean(options?.isStackFrame)
    };
    if (options?.name !== undefined) scope.name = options.name;
    if (options?.kind !== undefined) scope.kind = options.kind;
    if (this.#scopeStack.length > 0) {
      scope.parent = this.#scopeStack.at(-1);
    }
    this.#scopeStack.push(scope);
    this.#knownScopes.add(scope);
    if (options?.key !== undefined) this.#keyToScope.set(options.key, scope);
    return this;
  }
  setScopeName(name) {
    const scope = this.#scopeStack.at(-1);
    if (scope) scope.name = name;
    return this;
  }
  setScopeKind(kind) {
    const scope = this.#scopeStack.at(-1);
    if (scope) scope.kind = kind;
    return this;
  }
  setScopeStackFrame(isStackFrame) {
    const scope = this.#scopeStack.at(-1);
    if (scope) scope.isStackFrame = isStackFrame;
    return this;
  }
  setScopeVariables(variables) {
    const scope = this.#scopeStack.at(-1);
    if (scope) scope.variables = variables.slice(0);
    return this;
  }
  endScope(line, column) {
    const scope = this.#scopeStack.pop();
    if (!scope) return this;
    scope.end = {
      line,
      column
    };
    if (this.#scopeStack.length === 0) {
      this.#scopes.push(scope);
    } else {
      this.#scopeStack.at(-1).children.push(scope);
    }
    this.#lastScope = scope;
    return this;
  }
  /**
   * @returns The OriginalScope opened with the most recent `startScope` call, but not yet closed.
   */ currentScope() {
    return this.#scopeStack.at(-1) ?? null;
  }
  /**
   * @returns The most recent OriginalScope closed with `endScope`.
   */ lastScope() {
    return this.#lastScope;
  }
  /**
   * @param option The definition 'scope' of this range can either be the "OriginalScope" directly
   * (produced by this builder) or the scope's key set while building the scope.
   */ startRange(line, column, options) {
    const range = {
      start: {
        line,
        column
      },
      end: {
        line,
        column
      },
      isStackFrame: Boolean(options?.isStackFrame),
      isHidden: Boolean(options?.isHidden),
      values: options?.values ?? [],
      children: []
    };
    if (this.#rangeStack.length > 0) {
      range.parent = this.#rangeStack.at(-1);
    }
    if (options?.scope !== undefined) {
      range.originalScope = options.scope;
    } else if (options?.scopeKey !== undefined) {
      range.originalScope = this.#keyToScope.get(options.scopeKey);
    }
    if (options?.callSite) {
      range.callSite = options.callSite;
    }
    this.#rangeStack.push(range);
    return this;
  }
  setRangeDefinitionScope(scope) {
    const range = this.#rangeStack.at(-1);
    if (range) range.originalScope = scope;
    return this;
  }
  setRangeDefinitionScopeKey(scopeKey) {
    const range = this.#rangeStack.at(-1);
    if (range) range.originalScope = this.#keyToScope.get(scopeKey);
    return this;
  }
  setRangeStackFrame(isStackFrame) {
    const range = this.#rangeStack.at(-1);
    if (range) range.isStackFrame = isStackFrame;
    return this;
  }
  setRangeHidden(isHidden) {
    const range = this.#rangeStack.at(-1);
    if (range) range.isHidden = isHidden;
    return this;
  }
  setRangeValues(values) {
    const range = this.#rangeStack.at(-1);
    if (range) range.values = values;
    return this;
  }
  setRangeCallSite(callSite) {
    const range = this.#rangeStack.at(-1);
    if (range) range.callSite = callSite;
    return this;
  }
  endRange(line, column) {
    const range = this.#rangeStack.pop();
    if (!range) return this;
    range.end = {
      line,
      column
    };
    if (this.#rangeStack.length === 0) {
      this.#ranges.push(range);
    } else {
      this.#rangeStack.at(-1).children.push(range);
    }
    return this;
  }
  build() {
    const info = {
      scopes: this.#scopes,
      ranges: this.#ranges
    };
    this.#scopes = [];
    this.#ranges = [];
    this.#knownScopes.clear();
    return info;
  }
  get scopeStack() {
    return this.#scopeStack;
  }
  get rangeStack() {
    return this.#rangeStack;
  }
  isKnownScope(scope) {
    return this.#knownScopes.has(scope);
  }
  isValidScopeKey(key) {
    return this.#keyToScope.has(key);
  }
  getScopeByValidKey(key) {
    return this.#keyToScope.get(key);
  }
}
//# sourceMappingURL=builder.js.map