v0.17.15

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• Allow keywords as type parameter names in mapped types (#​3033)

  TypeScript allows type keywords to be used as parameter names in mapped types. Previously esbuild incorrectly treated this as an error. Code that does this is now supported:

  type Foo = 'a' | 'b' | 'c'
  type A = { [keyof in Foo]: number }
  type B = { [infer in Foo]: number }
  type C = { [readonly in Foo]: number }

• Add annotations for re-exported modules in node (#​2486, #​3029)

  Node lets you import named imports from a CommonJS module using ESM import syntax. However, the allowed names aren't derived from the properties of the CommonJS module. Instead they are derived from an arbitrary syntax-only analysis of the CommonJS module's JavaScript AST.

  To accommodate node doing this, esbuild's ESM-to-CommonJS conversion adds a special non-executable "annotation" for node that describes the exports that node should expose in this scenario. It takes the form 0 && (module.exports = { ... }) and comes at the end of the file (0 && expr means expr is never evaluated).

  Previously esbuild didn't do this for modules re-exported using the export * from syntax. Annotations for these re-exports will now be added starting with this release:

  // Original input
  export { foo } from './foo'
  export * from './bar'
  
  // Old output (with --format=cjs --platform=node)
  ...
  0 && (module.exports = {
    foo
  });
  
  // New output (with --format=cjs --platform=node)
  ...
  0 && (module.exports = {
    foo,
    ...require("./bar")
  });

  Note that you need to specify both --format=cjs and --platform=node to get these node-specific annotations.

• Avoid printing an unnecessary space in between a number and a . (#​3026)

  JavaScript typically requires a space in between a number token and a . token to avoid the . being interpreted as a decimal point instead of a member expression. However, this space is not required if the number token itself contains a decimal point, an exponent, or uses a base other than 10. This release of esbuild now avoids printing the unnecessary space in these cases:

  // Original input
  foo(1000 .x, 0 .x, 0.1 .x, 0.0001 .x, 0xFFFF_0000_FFFF_0000 .x)
  
  // Old output (with --minify)
  foo(1e3 .x,0 .x,.1 .x,1e-4 .x,0xffff0000ffff0000 .x);
  
  // New output (with --minify)
  foo(1e3.x,0 .x,.1.x,1e-4.x,0xffff0000ffff0000.x);

• Fix server-sent events with live reload when writing to the file system root (#​3027)

  This release fixes a bug where esbuild previously failed to emit server-sent events for live reload when outdir was the file system root, such as /. This happened because / is the only path on Unix that cannot have a trailing slash trimmed from it, which was fixed by improved path handling.