node_modules/@angular/material/core/density/private/_all-density.scss

@import '../../theming/theming';
@import '../../../expansion/expansion-theme';
@import '../../../stepper/stepper-theme';
@import '../../../toolbar/toolbar-theme';
@import '../../../tree/tree-theme';
@import '../../../paginator/paginator-theme';
@import '../../../form-field/form-field-theme';
@import '../../../button-toggle/button-toggle-theme';

// Includes all of the density styles.
@mixin angular-material-density($config-or-theme) {
  // In case a theme object has been passed instead of a configuration for
  // the density system, extract the density config from the theme object.
  $config: if(mat-private-is-theme-object($config-or-theme),
      mat-get-density-config($config-or-theme), $config-or-theme);

  @if $config == null {
    @error 'No density configuration specified.';
  }

  // TODO: COMP-309: Do not use individual mixins. Instead, use the all-theme mixin and only
  // specify a `density` config while setting `color` and `typography` to `null`. This is currently
  // not possible as it would introduce a circular dependency for density because the `mat-core`
  // mixin that is transitively loaded by the `all-theme` file, imports `all-density` which
  // would then load `all-theme` again. This ultimately results a circular dependency.

  @include mat-expansion-panel-density($config);
  @include mat-stepper-density($config);
  @include mat-toolbar-density($config);
  @include mat-tree-density($config);
  @include mat-paginator-density($config);
  @include mat-form-field-density($config);
  @include mat-button-toggle-density($config);
}