getEmptyChunkReplacer() — vite Function Reference

Architecture documentation for the getEmptyChunkReplacer() function in css.ts from the vite codebase.

Function typescript PluginSystem AssetManagement calls 1 called by 1

Entity Profile

PluginSystem→ AssetManagement→ getEmptyChunkReplacer() — vite Function Reference

Dependency Diagram

graph TD
  98ef77ec_2e97_a945_fa45_32171e0ad8dc["getEmptyChunkReplacer()"]
  c3eb47df_971b_0616_6c9f_29b3ded72224["css.ts"]
  98ef77ec_2e97_a945_fa45_32171e0ad8dc -->|defined in| c3eb47df_971b_0616_6c9f_29b3ded72224
  cd131d16_e223_ab79_1b7c_8ea449ae51a2["cssPostPlugin()"]
  cd131d16_e223_ab79_1b7c_8ea449ae51a2 -->|calls| 98ef77ec_2e97_a945_fa45_32171e0ad8dc
  5e378bd7_4558_94a6_54bf_d9742f54d2e9["escapeRegex()"]
  98ef77ec_2e97_a945_fa45_32171e0ad8dc -->|calls| 5e378bd7_4558_94a6_54bf_d9742f54d2e9
  style 98ef77ec_2e97_a945_fa45_32171e0ad8dc fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

packages/vite/src/node/plugins/css.ts lines 1238–1272

export function getEmptyChunkReplacer(
  pureCssChunkNames: string[],
  outputFormat: InternalModuleFormat,
): (code: string) => string {
  const emptyChunkFiles = pureCssChunkNames
    .map((file) => escapeRegex(path.basename(file)))
    .join('|')

  // for cjs, require calls might be chained by minifier using the comma operator.
  // in this case we have to keep one comma if a next require is chained
  // or add a semicolon to terminate the chain.
  const emptyChunkRE = new RegExp(
    outputFormat === 'es'
      ? `\\bimport\\s*["'][^"']*(?:${emptyChunkFiles})["'];`
      : `(\\b|,\\s*)require\\(\\s*["'\`][^"'\`]*(?:${emptyChunkFiles})["'\`]\\)(;|,)`,
    'g',
  )

  return (code: string) =>
    code.replace(
      emptyChunkRE,
      // remove css import while preserving source map location
      (m, p1, p2) => {
        if (outputFormat === 'es') {
          return `/* empty css ${''.padEnd(m.length - 15)}*/`
        }
        if (p2 === ';') {
          // if it ends with `;`, move it before and remove the leading `,`
          return `${p2}/* empty css ${''.padEnd(m.length - 16)}*/`
        }
        // if it ends with `,`, remove it but keep the leading `,` if exists
        return `${p1}/* empty css ${''.padEnd(m.length - 15 - p1.length)}*/`
      },
    )
}