addPragmaToFixture() — react Function Reference

Architecture documentation for the addPragmaToFixture() function in enable-feature-flag.js from the react codebase.

Function javascript BabelCompiler Entrypoint called by 1

Entity Profile

BabelCompiler→ Entrypoint→ addPragmaToFixture() — react Function Reference

Dependency Diagram

graph TD
  58164e4d_3af0_d588_b322_d2416e5a91c6["addPragmaToFixture()"]
  fdb06a3a_b735_af93_2b10_31380c21c8b7["enable-feature-flag.js"]
  58164e4d_3af0_d588_b322_d2416e5a91c6 -->|defined in| fdb06a3a_b735_af93_2b10_31380c21c8b7
  ab68ec04_512e_f89e_9e49_ae73608023f0["main()"]
  ab68ec04_512e_f89e_9e49_ae73608023f0 -->|calls| 58164e4d_3af0_d588_b322_d2416e5a91c6
  style 58164e4d_3af0_d588_b322_d2416e5a91c6 fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

compiler/scripts/enable-feature-flag.js lines 174–205

function addPragmaToFixture(filePath, flagName) {
  const content = fs.readFileSync(filePath, 'utf8');
  const lines = content.split('\n');

  if (lines.length === 0) {
    console.warn(`Warning: Empty file ${filePath}`);
    return false;
  }

  const firstLine = lines[0];
  const pragma = `@${flagName}:false`;

  // Check if pragma already exists
  if (firstLine.includes(pragma)) {
    return false; // Already has the pragma
  }

  // Check if first line is a single-line comment
  if (firstLine.trim().startsWith('//')) {
    // Append pragma to existing comment
    lines[0] = firstLine + ' ' + pragma;
  } else if (firstLine.trim().startsWith('/*')) {
    // Multi-line comment - insert new line before it
    lines.unshift('// ' + pragma);
  } else {
    // No comment - insert new comment as first line
    lines.unshift('// ' + pragma);
  }

  fs.writeFileSync(filePath, lines.join('\n'), 'utf8');
  return true;
}