fix(material/button): generate separate tokens for mini fab

Currently the mini FAB uses the same tokens as the regular one. This is incorrect and causes inconsistencies in M3. These changes split the mini FAB out into its own set of tokens.

Author: crisbeto

src/material-experimental/theming/_custom-tokens.scss

@@ -355,6 +355,47 @@
   ));
 }
 
+/// Generates custom tokens for the mat-mini-fab.
+/// @param {Map} $systems The MDC system tokens
+/// @param {Boolean} $exclude-hardcoded Whether to exclude hardcoded token values
+/// @return {Map} A set of custom tokens for the mat-mini-fab
+@function fab-small($systems, $exclude-hardcoded) {
+  @return ((
+    foreground-color: map.get($systems, md-sys-color, on-primary-container),
+    state-layer-color: map.get($systems, md-sys-color, primary-container),
+    ripple-color: mat.private-safe-color-change(
+      map.get($systems, md-sys-color, on-primary-container),
+      $alpha: map.get($systems, md-sys-state, pressed-state-layer-opacity)
+    ),
+    hover-state-layer-opacity: map.get($systems, md-sys-state, hover-state-layer-opacity),
+    focus-state-layer-opacity: map.get($systems, md-sys-state, focus-state-layer-opacity),
+    pressed-state-layer-opacity: map.get($systems, md-sys-state, pressed-state-layer-opacity),
+    disabled-state-container-color: mat.private-safe-color-change(
+      map.get($systems, md-sys-color, on-surface), $alpha: 0.12),
+    disabled-state-foreground-color: mat.private-safe-color-change(
+      map.get($systems, md-sys-color, on-surface), $alpha: 0.38),
+  ), (
+    // Color variants
+    primary: (), // Default, no overrides needed.
+    secondary: (
+      foreground-color: map.get($systems, md-sys-color, on-secondary-container),
+      state-layer-color: map.get($systems, md-sys-color, secondary-container),
+      ripple-color: mat.private-safe-color-change(
+          map.get($systems, md-sys-color, on-secondary-container),
+        $alpha: map.get($systems, md-sys-state, pressed-state-layer-opacity)
+      ),
+    ),
+    tertiary: (
+      foreground-color: map.get($systems, md-sys-color, on-tertiary-container),
+      state-layer-color: map.get($systems, md-sys-color, tertiary-container),
+      ripple-color: mat.private-safe-color-change(
+          map.get($systems, md-sys-color, on-tertiary-container),
+        $alpha: map.get($systems, md-sys-state, pressed-state-layer-opacity)
+      ),
+    )
+  ));
+}
+
 /// Generates custom tokens for the mat-form-field.
 /// @param {Map} $systems The MDC system tokens
 /// @param {Boolean} $exclude-hardcoded Whether to exclude hardcoded token values

src/material-experimental/theming/_m3-density.scss

@@ -27,6 +27,7 @@ $_density-tokens: (
   (mdc, elevated-card): (),
   (mdc, extended-fab): (),
   (mdc, fab): (),
+  (mdc, fab-small): (),
   (mdc, filled-text-field): (),
   (mdc, text-button): (
     container-height: (40px, 36px, 32px, 28px),

src/material-experimental/theming/_m3-tokens.scss

@@ -503,6 +503,19 @@
       ),
       $token-slots
     ),
+    _namespace-tokens(
+      (mdc, fab-small),
+      (
+        mdc-tokens.md-comp-fab-primary-small-values($systems, $exclude-hardcoded),
+        (
+          // Color variants
+          primary: (), // Default, no overrides needed.
+          secondary: mdc-tokens.md-comp-fab-secondary-small-values($systems, $exclude-hardcoded),
+          tertiary: mdc-tokens.md-comp-fab-tertiary-small-values($systems, $exclude-hardcoded)
+        )
+      ),
+      $token-slots
+    ),
     _namespace-tokens(
       (mdc, extended-fab),
       (
@@ -703,6 +716,11 @@
       custom-tokens.fab($systems, $exclude-hardcoded),
       $token-slots
     ),
+    _namespace-tokens(
+      (mat, fab-small),
+      custom-tokens.fab-small($systems, $exclude-hardcoded),
+      $token-slots
+    ),
     _namespace-tokens(
       (mat, form-field),
       custom-tokens.form-field($systems, $exclude-hardcoded),

src/material/button/_fab-theme.scss

@@ -1,11 +1,14 @@
 @use '@material/fab/fab-theme' as mdc-fab-theme;
+@use '@material/fab/fab-small-theme' as mdc-fab-small-theme;
 @use '@material/fab/extended-fab-theme' as mdc-extended-fab-theme;
 @use '../core/style/sass-utils';
 @use '../core/theming/theming';
 @use '../core/theming/inspection';
 @use '../core/tokens/m2/mdc/fab' as tokens-mdc-fab;
+@use '../core/tokens/m2/mdc/fab-small' as tokens-mdc-fab-small;
 @use '../core/tokens/m2/mdc/extended-fab' as tokens-mdc-extended-fab;
 @use '../core/tokens/m2/mat/fab' as tokens-mat-fab;
+@use '../core/tokens/m2/mat/fab-small' as tokens-mat-fab-small;
 @use '../core/tokens/token-utils';
 @use '../core/typography/typography';
 
@@ -20,6 +23,7 @@
     // Add default values for tokens not related to color, typography, or density.
     @include sass-utils.current-selector-or-root() {
       @include mdc-fab-theme.theme(tokens-mdc-fab.get-unthemable-tokens());
+      @include mdc-fab-small-theme.theme(tokens-mdc-fab-small.get-unthemable-tokens());
       @include mdc-extended-fab-theme.theme(
           tokens-mdc-extended-fab.get-unthemable-tokens()
       );
@@ -42,6 +46,21 @@
   @include token-utils.create-token-values(tokens-mat-fab.$prefix, $mat-tokens);
 }
 
+@mixin _fab-small-variant($theme, $palette) {
+  $mdc-tokens: if($palette,
+    tokens-mdc-fab-small.private-get-color-palette-color-tokens($theme, $palette),
+    tokens-mdc-fab-small.get-color-tokens($theme)
+  );
+
+  $mat-tokens: if($palette,
+    tokens-mat-fab-small.private-get-color-palette-color-tokens($theme, $palette),
+    tokens-mat-fab-small.get-color-tokens($theme)
+  );
+
+  @include mdc-fab-small-theme.theme($mdc-tokens);
+  @include token-utils.create-token-values(tokens-mat-fab-small.$prefix, $mat-tokens);
+}
+
 /// Outputs color theme styles for the mat-fab.
 /// @param {Map} $theme The theme to generate color styles for.
 /// @param {ArgList} Additional optional arguments (only supported for M3 themes):
@@ -54,10 +73,10 @@
   @else {
     @include sass-utils.current-selector-or-root() {
       @include _fab-variant($theme, null);
+      @include _fab-small-variant($theme, null);
       @include mdc-extended-fab-theme.theme(tokens-mdc-extended-fab.get-color-tokens($theme));
 
-      .mat-mdc-fab,
-      .mat-mdc-mini-fab {
+      .mat-mdc-fab {
         &.mat-primary {
           @include _fab-variant($theme, primary);
         }
@@ -70,6 +89,20 @@
           @include _fab-variant($theme, warn);
         }
       }
+
+      .mat-mdc-mini-fab {
+        &.mat-primary {
+          @include _fab-small-variant($theme, primary);
+        }
+
+        &.mat-accent {
+          @include _fab-small-variant($theme, accent);
+        }
+
+        &.mat-warn {
+          @include _fab-small-variant($theme, warn);
+        }
+      }
     }
   }
 }
@@ -85,6 +118,8 @@
       @include mdc-extended-fab-theme.theme(tokens-mdc-extended-fab.get-typography-tokens($theme));
       @include token-utils.create-token-values(tokens-mat-fab.$prefix,
         tokens-mat-fab.get-typography-tokens($theme));
+      @include token-utils.create-token-values(tokens-mat-fab-small.$prefix,
+        tokens-mat-fab-small.get-typography-tokens($theme));
     }
   }
 }
@@ -99,6 +134,8 @@
     @include sass-utils.current-selector-or-root() {
       @include token-utils.create-token-values(tokens-mat-fab.$prefix,
         tokens-mat-fab.get-density-tokens($theme));
+      @include token-utils.create-token-values(tokens-mat-fab-small.$prefix,
+        tokens-mat-fab-small.get-density-tokens($theme));
     }
   }
 }
@@ -132,8 +169,14 @@
   $mdc-extended-fab-tokens: token-utils.get-tokens-for(
       $tokens, tokens-mdc-extended-fab.$prefix, $options...);
   $mdc-fab-tokens: token-utils.get-tokens-for($tokens, tokens-mdc-fab.$prefix, $options...);
+  $mdc-fab-small-tokens: token-utils.get-tokens-for($tokens, tokens-mdc-fab-small.$prefix,
+    $options...);
   $mat-fab-tokens: token-utils.get-tokens-for($tokens, tokens-mat-fab.$prefix, $options...);
+  $mat-fab-small-tokens: token-utils.get-tokens-for($tokens, tokens-mat-fab-small.$prefix,
+    $options...);
   @include mdc-extended-fab-theme.theme($mdc-extended-fab-tokens);
   @include mdc-fab-theme.theme($mdc-fab-tokens);
+  @include mdc-fab-small-theme.theme($mdc-fab-small-tokens);
   @include token-utils.create-token-values(tokens-mat-fab.$prefix, $mat-fab-tokens);
+  @include token-utils.create-token-values(tokens-mat-fab-small.$prefix, $mat-fab-small-tokens);
 }

src/material/button/fab.scss

@@ -2,6 +2,7 @@
 @use '@material/fab' as mdc-fab;
 @use '@material/fab/extended-fab-theme' as mdc-extended-fab-theme;
 @use '@material/fab/fab-theme' as mdc-fab-theme;
+@use '@material/fab/fab-small-theme' as mdc-fab-small-theme;
 @use '@material/typography/typography' as mdc-typography;
 @use '@material/theme/custom-properties' as mdc-custom-properties;
 
@@ -13,9 +14,12 @@
 @use '../core/tokens/m2/mdc/extended-fab' as tokens-mdc-extended-fab;
 @use '../core/tokens/m2/mdc/fab' as tokens-mdc-fab;
 @use '../core/tokens/m2/mat/fab' as tokens-mat-fab;
+@use '../core/tokens/m2/mdc/fab-small' as tokens-mdc-fab-small;
+@use '../core/tokens/m2/mat/fab-small' as tokens-mat-fab-small;
 
 @include mdc-custom-properties.configure($emit-fallback-values: false, $emit-fallback-vars: false) {
   $mdc-fab-token-slots: tokens-mdc-fab.get-token-slots();
+  $mdc-fab-small-token-slots: tokens-mdc-fab-small.get-token-slots();
   $mdc-extended-fab-token-slots: tokens-mdc-extended-fab.get-token-slots();
   $exclude-tokens: (
     // Exclude the elevation tokens here since we output them manually below.
@@ -30,10 +34,15 @@
   // some unnecessary typography styles for the extended FAB.
   @include mdc-fab.static-styles($query: mdc-helpers.$mdc-base-styles-query);
 
-  .mat-mdc-fab, .mat-mdc-mini-fab {
+  .mat-mdc-fab {
     @include mdc-fab-theme.theme-styles(map.merge($mdc-fab-token-slots, $exclude-tokens));
   }
 
+  .mat-mdc-mini-fab {
+    @include mdc-fab-small-theme.theme-styles(
+      map.merge($mdc-fab-small-token-slots, $exclude-tokens));
+  }
+
   .mat-mdc-extended-fab {
     // Before tokens MDC included the font smoothing automatically, but with
     // tokens it doesn't. We add it since it can cause tiny differences in
@@ -46,47 +55,9 @@
 
 .mat-mdc-fab, .mat-mdc-mini-fab {
   @include button-base.mat-private-button-interactive();
-  @include button-base.mat-private-button-touch-target(true, tokens-mat-fab.$prefix,
-    tokens-mat-fab.get-token-slots());
-  @include button-base.mat-private-button-ripple(tokens-mat-fab.$prefix,
-    tokens-mat-fab.get-token-slots());
   @include style-private.private-animation-noop();
   flex-shrink: 0; // Prevent the button from shrinking since it's always supposed to be a circle.
 
-  @include mdc-helpers.disable-mdc-fallback-declarations {
-    @include token-utils.use-tokens(tokens-mat-fab.$prefix, tokens-mat-fab.get-token-slots()) {
-      @include token-utils.create-token-slot(color, foreground-color, inherit);
-    }
-  }
-
-  @include token-utils.use-tokens(tokens-mdc-fab.$prefix, tokens-mdc-fab.get-token-slots()) {
-    @include button-base.mat-private-button-elevation(container-elevation);
-
-    &:hover {
-      @include button-base.mat-private-button-elevation(hover-container-elevation);
-    }
-
-    &:focus {
-      @include button-base.mat-private-button-elevation(focus-container-elevation);
-    }
-
-    &:active, &:focus:active {
-      @include button-base.mat-private-button-elevation(pressed-container-elevation);
-    }
-  }
-
-  @include button-base.mat-private-button-disabled {
-    // Necessary for interactive disabled buttons.
-    &, &:focus {
-      box-shadow: none;
-    }
-
-    @include token-utils.use-tokens(tokens-mat-fab.$prefix, tokens-mat-fab.get-token-slots()) {
-      @include token-utils.create-token-slot(color, disabled-state-foreground-color);
-      @include token-utils.create-token-slot(background-color, disabled-state-container-color);
-    }
-  }
-
   // MDC adds some styles to fab and mini-fab that conflict with some of our focus indicator
   // styles and don't actually do anything. This undoes those conflicting styles.
   &:not(.mdc-ripple-upgraded):focus::before {
@@ -111,11 +82,17 @@
     $offset: calc(#{$border-width} + 2px);
     margin: calc(#{$offset} * -1);
   }
+
+  @include button-base.mat-private-button-disabled {
+    // Necessary for interactive disabled buttons.
+    &, &:focus {
+      box-shadow: none;
+    }
+  }
 }
 
-.mat-mdc-extended-fab {
-  @include token-utils.use-tokens(tokens-mdc-extended-fab.$prefix,
-    tokens-mdc-extended-fab.get-token-slots()) {
+@mixin _fab-elevation($mdc-tokens) {
+  @include token-utils.use-tokens($mdc-tokens...) {
     @include button-base.mat-private-button-elevation(container-elevation);
 
     &:hover {
@@ -130,6 +107,45 @@
       @include button-base.mat-private-button-elevation(pressed-container-elevation);
     }
   }
+}
+
+@mixin _fab-structure($mdc-tokens, $mat-tokens) {
+  @include button-base.mat-private-button-touch-target(true, $mat-tokens...);
+  @include button-base.mat-private-button-ripple($mat-tokens...);
+
+  @include mdc-helpers.disable-mdc-fallback-declarations {
+    @include token-utils.use-tokens($mat-tokens...) {
+      @include token-utils.create-token-slot(color, foreground-color, inherit);
+    }
+  }
+
+  @include _fab-elevation($mdc-tokens);
+
+  @include button-base.mat-private-button-disabled {
+    @include token-utils.use-tokens($mat-tokens...) {
+      @include token-utils.create-token-slot(color, disabled-state-foreground-color);
+      @include token-utils.create-token-slot(background-color, disabled-state-container-color);
+    }
+  }
+}
+
+.mat-mdc-fab {
+  @include _fab-structure(
+    (tokens-mdc-fab.$prefix, tokens-mdc-fab.get-token-slots()),
+    (tokens-mat-fab.$prefix, tokens-mat-fab.get-token-slots()),
+  );
+}
+
+.mat-mdc-mini-fab {
+  @include _fab-structure(
+    (tokens-mdc-fab-small.$prefix, tokens-mdc-fab-small.get-token-slots()),
+    (tokens-mat-fab-small.$prefix, tokens-mat-fab-small.get-token-slots()),
+  );
+}
+
+.mat-mdc-extended-fab {
+  @include _fab-elevation((tokens-mdc-extended-fab.$prefix,
+    tokens-mdc-extended-fab.get-token-slots()));
 
   @include button-base.mat-private-button-disabled {
     // Necessary for interactive disabled buttons.
@@ -146,6 +162,12 @@
     );
   }
 
+  // All FABs are square except the extended ones so we
+  // need to set the touch target back to full-width.
+  .mat-mdc-button-touch-target {
+    width: 100%;
+  }
+
   // For Extended FAB with text label followed by icon.
   // We are checking for the a button class because white this is a FAB it
   // uses the same template as button.
@@ -159,8 +181,3 @@
   }
 }
 
-// All FABs are square except the extended ones so we
-// need to set the touch target back to full-width.
-.mat-mdc-extended-fab .mat-mdc-button-touch-target {
-  width: 100%;
-}