Sass: Resolving component dependencies #sass

SassMeister-input.scss

// Sass: Resolving component dependencies

// Other ideas: https://github.com/whizark/xass#ideas

// The storage for dependency management
$container: (
  -components: (),
  -frozen: ()
);

// Functions
@function components() {
  @return map-get($container, '-components');
}

@function -frozen() {
  @return map-get($container, '-frozen');
}

@function -is-frozen($id) {
  $frozen: -frozen();

  @return (index($frozen, $id) != null);
}

@function component($id) {
  $components: components();

  @if not map-has-key($components, $id) {
    @error 'The id #{id} is not registered.';
  }

  @return map-get($components, $id);
}

@function component-name($id) {
  $component: component($id);

  @return map-get($component, '-name');
}

@function component-dependencies($id) {
  $component: component($id);

  @return map-get($component, '-dependencies');
}

@function component-path($id) {
  $component: component($id);

  @return map-get($component, '-path');
}

@function register($id, $dependencies: (), $path: null) {
  @if -is-frozen($id) {
    @error 'The id #{$id} has already been resolved.';
  }

  $components: components();
  $properties: (
    -name : $id,
    -dependencies: $dependencies,
    -path: $path
  );
  $components: map-merge($components, (#{$id}: $properties));
  $container: map-merge($container, (-components: $components));

  @return $container;
}

// Register a component and the dependencies
@mixin register($id, $dependencies: (), $path: null)
{
  $container: register($id, $dependencies, $path) !global;
}

// Resolve dependencies
@function resolve($id) {
  $paths: ();
  $components: components();

  $dependencies: component-dependencies($id);

  @each $dependency in $dependencies {
    @if not -is-frozen($dependency) {
      $paths: append($paths, resolve($dependency), comma);
    }
  }

  @if not -is-frozen($id) {
    $paths: append($paths, component-path($id), comma);
    $frozen: append(-frozen(), $id);
    $container: map-merge($container, (-frozen: $frozen)) !global;
  }

  @return $paths;
}

// Component definitions
@include register('component-1', ('dependency-2', 'dependency-1'), '_component-1');
@include register('dependency-2', ('dependency-1'), '_dependency-2');
@include register('dependency-1', (), '_dependency-1');

// Tests
.resolver {
  $paths: inspect(resolve('component-1'));

  // Returns filepaths based on the dependencies.
  component-1: $paths;

  // Returns empty string after the dependencies are resolved.
  component-1: inspect(resolve('component-1'));
}

// @todo Normalize List & import components
// @import $paths;

SassMeister-output.css

.resolver {
  component-1: ((("_dependency-1",)), "_dependency-2"), "_component-1";
  component-1: ();
}