material-web/typography/_typeface.scss

//
// Copyright 2023 Google LLC
// SPDX-License-Identifier: Apache-2.0
//

// go/keep-sorted start
@use 'sass:list';
// go/keep-sorted end
// go/keep-sorted start
@use '../tokens';
// go/keep-sorted end

/// `typeface.theme()` emits `--md-ref-typeface-*` custom properties for given
/// font families and weights.
///
/// Use this to change the font families or weights for all typescales.
///
/// @example scss
///   @use '@material/web/typography/typeface';
///
///   :root {
///     @include typeface.theme(
///       'brand': 'Open Sans',
///       'plain': sans-serif,
///       'weight-bold': 900,
///     );
///   }
///
///   /* Generated CSS */
///   :root {
///     --md-ref-typeface-brand: 'Open Sans';
///     --md-ref-typeface-plain: sans-serif;
///     --md-ref-typeface-weight-bold: 900;
///   }
///
/// @param {Map} $tokens - A Map with `md-ref-typeface` token name keys and
///     their corresponding font family or weight values.
/// @output Emits `--md-ref-typeface-*` custom properties.
@mixin theme($tokens) {
  @each $token, $value in $tokens {
    @if list.index(tokens.$md-ref-typeface-supported-tokens, $token) == null {
      @error 'md-ref-typeface `#{$token}` is not a supported token.';
    }

    @if $value {
      --md-ref-typeface-#{$token}: #{$value};
    }
  }
}