--footer esbuild & rollup style!

[versecafe]

What does this PR do?

This implements the --footer flag for bun build adds the footer field to bun.d.ts BuildOptions, implements footer additions into the bundler and shifting the source-map start point to work correctly with footers

• Documentation
• Types changes
• Code changes

How did you verify your code works?

Automated tests in + hand testing of sourcemap compatibility

• I included a test for the new code, or existing tests cover it
• I checked the lifetime of memory allocated to verify it's (1) freed and (2) only freed when it should be
• I wrote TypeScript/JavaScript tests and they pass locally (bun-debug test test-file-name.test)

Examples

const enum LogLevel {
  INFO,
  WARN,
  ERROR,
}

function log(data: string, level: LogLevel) {
  switch (level) {
    case LogLevel.INFO:
      console.log(data);
      break;
    case LogLevel.WARN:
      console.warn(data);
      break;
    case LogLevel.ERROR:
      console.error(data);
      break;
  }
}

log("Hey what's good, not this it's broken", LogLevel.ERROR);

bun build index.ts --outdir=./dist --minify --footer="// made with love in SF" --sourcemap="external"

await Bun.build({
  entrypoints: ["./index.ts"],
  outdir: "./dist",
  minify: true,
  sourcemap: "linked",
  footer: "// made with love in SF",
});

Both of these result in

function e(o,s){switch(s){case 0:console.log(o);break;case 1:console.warn(o);break;case 2:console.error(o);break}}e("Hey what's good, not this it's broken",2);

// made with love in SF

//# debugId=D6C4F8A4A7CB8B9F64756E2164756E21
//# sourceMappingURL=index.js.map

{
  "version": 3,
  "sources": ["../index.ts"],
  "sourcesContent": [
    "const enum LogLevel {\n  INFO,\n  WARN,\n  ERROR,\n}\n\nfunction log(data: string, level: LogLevel) {\n  switch (level) {\n    case LogLevel.INFO:\n      console.log(data);\n      break;\n    case LogLevel.WARN:\n      console.warn(data);\n      break;\n    case LogLevel.ERROR:\n      console.error(data);\n      break;\n  }\n}\n\nlog(\"Hey what's good, not this it's broken\", LogLevel.ERROR);\n"
  ],
  "mappings": "AAMA,SAAS,CAAG,CAAC,EAAc,EAAiB,CAC1C,OAAQ,OACD,GACH,QAAQ,IAAI,CAAI,EAChB,UACG,GACH,QAAQ,KAAK,CAAI,EACjB,UACG,GACH,QAAQ,MAAM,CAAI,EAClB,OAIN,EAAI,wCAAyC,CAAc",
  "debugId": "D6C4F8A4A7CB8B9F64756E2164756E21",
  "names": []
}

This also allows nice things like automatic copyright statements

await Bun.build({
  entrypoints: ["./index.ts"],
  outdir: "./dist",
  minify: true,
  sourcemap: "linked",
  footer: `/**
 * This is copyright of [...] ${new Date().getFullYear()}
 * do not redistribute without consent of [...]
*/`,
});

function e(o,s){switch(s){case 0:console.log(o);break;case 1:console.warn(o);break;case 2:console.error(o);break}}e("Hey what's good, not this it's broken",2);

/**
 * This is copyright of [...] 2024
 * do not redistribute without consent of [...]
*/

//# debugId=49D4166E8D5C94DD64756E2164756E21
//# sourceMappingURL=index.js.map