doEval() — react Function Reference

Architecture documentation for the doEval() function in evaluator.ts from the react codebase.

Function typescript BabelCompiler Entrypoint calls 2 called by 1

Entity Profile

BabelCompiler→ Entrypoint→ doEval() — react Function Reference

Dependency Diagram

graph TD
  c8090524_9cfa_099d_cf1f_dcf1a93439f8["doEval()"]
  e04df78a_8312_1a6c_3ce1_ea408e44a1d7["evaluator.ts"]
  c8090524_9cfa_099d_cf1f_dcf1a93439f8 -->|defined in| e04df78a_8312_1a6c_3ce1_ea408e44a1d7
  81e68010_37f1_e748_b452_7cc28e601cad["runSprout()"]
  81e68010_37f1_e748_b452_7cc28e601cad -->|calls| c8090524_9cfa_099d_cf1f_dcf1a93439f8
  15af1288_5ce1_7a3d_304e_01b40e750f72["push()"]
  c8090524_9cfa_099d_cf1f_dcf1a93439f8 -->|calls| 15af1288_5ce1_7a3d_304e_01b40e750f72
  850ee738_6992_b2d7_3104_159fba313678["evaluateFixtureExport()"]
  c8090524_9cfa_099d_cf1f_dcf1a93439f8 -->|calls| 850ee738_6992_b2d7_3104_159fba313678
  style c8090524_9cfa_099d_cf1f_dcf1a93439f8 fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

compiler/packages/snap/src/sprout/evaluator.ts lines 205–310

export function doEval(source: string): EvaluatorResult {
  'use strict';

  const originalConsole = globalThis.console;
  const logs: Array<string> = [];
  const mockedLog = (...args: Array<any>) => {
    logs.push(
      `${args.map(arg => {
        if (arg instanceof Error) {
          return arg.toString();
        } else {
          return util.inspect(arg);
        }
      })}`,
    );
  };

  (globalThis.console as any) = {
    info: mockedLog,
    log: mockedLog,
    warn: mockedLog,
    error: (...args: Array<any>) => {
      if (
        typeof args[0] === 'string' &&
        args[0].includes('ReactDOMTestUtils.act` is deprecated')
      ) {
        // remove this once @testing-library/react is upgraded to React 19.
        return;
      }

      const stack = new Error().stack?.split('\n', 5) ?? [];
      for (const stackFrame of stack) {
        // React warns on exceptions thrown during render, we avoid printing
        // here to reduce noise in test fixture outputs.
        if (
          (stackFrame.includes('at logCaughtError') &&
            stackFrame.includes('react-dom-client.development.js')) ||
          (stackFrame.includes('at defaultOnRecoverableError') &&
            stackFrame.includes('react-dom-client.development.js'))
        ) {
          return;
        }
      }
      mockedLog(...args);
    },
    table: mockedLog,
    trace: () => {},
  };
  try {
    // source needs to be evaluated in the same scope as invoke
    const evalResult: any = eval(`
    (() => {
      // Exports should be overwritten by source
      let exports = {
        FIXTURE_ENTRYPOINT: {
          fn: globalThis.placeholderFn,
          params: [],
        },
      };
      let reachedInvoke = false;
      try {
        // run in an iife to avoid naming collisions
        (() => {${source}})();
        reachedInvoke = true;
        if (exports.FIXTURE_ENTRYPOINT?.fn === globalThis.placeholderFn) {
          return {
            kind: "exception",
            value: "Fixture not implemented",
          };
        }
        return evaluateFixtureExport(exports);
      } catch (e) {
        if (!reachedInvoke) {
          return {
            kind: "UnexpectedError",
            value: e.message,
          };
        } else {
          return {
            kind: "exception",
            value: e.message,