An Elixir formatter plugin for Surface code.

Elixir 1.13 introduced formatter plugins, allowing the Surface formatter to run during mix format instead of requiring developers to run mix surface.format separately.

To format Surface code using Elixir 1.12 or earlier, use mix surface.format.

.formatter.exs setup

Add to :plugins in .formatter.exs in order to format ~F sigils and .sface files when running mix format.

Only works on files matching patterns in :inputs, so add patterns for all Surface files to ensure they're formatted.

# in .formatter.exs
[
  ...,
  import_deps: [:surface],
  plugins: [Surface.Formatter.Plugin],

  # add patterns matching all .sface files and all .ex files with ~F sigils
  inputs: ["*.{ex,exs}", "{config,lib,test}/**/*.{ex,exs,sface}"],

  # THE FOLLOWING ARE OPTIONAL:

  # set desired line length for both Elixir's code formatter and this one
  # (only affects opening tags in Surface)
  line_length: 80,

  # or, set line length only for Surface code (overrides `line_length`)
  surface_line_length: 84
]

Options

In .formatter.exs, the following options can be provided:

• :line_length - Maximum line length of an opening tag before SurfaceFormatter attempts to wrap it onto multiple lines. This option is used by Code.format_string!/2 and mix format and defaults to 98.
• :surface_line_length - Overrides :line_length; useful for setting separate desired line length for Surface code and non-Surface Elixir code.