v0.12.15

• Fix a bug with var() in CSS color lowering (#1421)

  This release fixes a bug with esbuild's handling of the rgb and hsl color functions when they contain var(). Each var() token sequence can be substituted for any number of tokens including zero or more than one, but previously esbuild's output was only correct if each var() inside of rgb or hsl contained exactly one token. With this release, esbuild will now not attempt to transform newer CSS color syntax to older CSS color syntax if it contains var():

  /* Original code */
  a {
    color: hsl(var(--hs), var(--l));
  }
  
  /* Old output */
  a {
    color: hsl(var(--hs), ,, var(--l));
  }
  
  /* New output */
  a {
    color: hsl(var(--hs), var(--l));
  }
  

  The bug with the old output above happened because esbuild considered the arguments to hsl as matching the pattern hsl(h s l) which is the new space-separated form allowed by CSS Color Module Level 4. Then esbuild tried to convert this to the form hsl(h, s, l) which is more widely supported by older browsers. But this substitution doesn't work in the presence of var(), so it has now been disabled in that case.