fix(material/button): support palettes for icon button in M3 (#29433)

Fixes that palettes weren't implemented for the icon button in M3. This was done initially, because M3 doesn't explicitly support palettes, but it can make it harder for users to migrate.

Fixes #29307.

Author: crisbeto

src/material/button/_icon-button-theme.scss

@@ -37,9 +37,13 @@
   @include token-utils.create-token-values(tokens-mat-icon-button.$prefix, $mat-tokens);
 }
 
-@mixin color($theme) {
+/// Outputs color theme styles for the mat-icon-button.
+/// @param {Map} $theme The theme to generate color styles for.
+/// @param {ArgList} Additional optional arguments (only supported for M3 themes):
+/// $color-variant: The color variant to use for the button: primary, secondary, tertiary, or error.
+@mixin color($theme, $options...) {
   @if inspection.get-theme-version($theme) == 1 {
-    @include _theme-from-tokens(inspection.get-theme-tokens($theme, color));
+    @include _theme-from-tokens(inspection.get-theme-tokens($theme, color), $options...);
   }
   @else {
     @include sass-utils.current-selector-or-root() {
@@ -122,10 +126,14 @@
   );
 }
 
-@mixin theme($theme) {
+/// Outputs all (base, color, typography, and density) theme styles for the mat-icon-button.
+/// @param {Map} $theme The theme to generate styles for.
+/// @param {ArgList} Additional optional arguments (only supported for M3 themes):
+/// $color-variant: The color variant to use for the button: primary, secondary, tertiary, or error.
+@mixin theme($theme, $options...) {
   @include theming.private-check-duplicate-theme-styles($theme, 'mat-icon-button') {
     @if inspection.get-theme-version($theme) == 1 {
-      @include _theme-from-tokens(inspection.get-theme-tokens($theme));
+      @include _theme-from-tokens(inspection.get-theme-tokens($theme), $options...);
     }
     @else {
       @include base($theme);
@@ -142,13 +150,14 @@
   }
 }
 
-@mixin _theme-from-tokens($tokens) {
+@mixin _theme-from-tokens($tokens, $options...) {
   @include validation.selector-defined(
       'Calls to Angular Material theme mixins with an M3 theme must be wrapped in a selector');
   @if ($tokens != ()) {
-    @include token-utils.create-token-values(
-        tokens-mdc-icon-button.$prefix, map.get($tokens, tokens-mdc-icon-button.$prefix));
-    @include token-utils.create-token-values(
-        tokens-mat-icon-button.$prefix, map.get($tokens, tokens-mat-icon-button.$prefix));
+    $mdc-tokens: token-utils.get-tokens-for($tokens, tokens-mdc-icon-button.$prefix, $options...);
+    $mat-tokens: token-utils.get-tokens-for($tokens, tokens-mat-icon-button.$prefix, $options...);
+
+    @include token-utils.create-token-values(tokens-mdc-icon-button.$prefix, $mdc-tokens);
+    @include token-utils.create-token-values(tokens-mat-icon-button.$prefix, $mat-tokens);
   }
 }

src/material/core/theming/_color-api-backwards-compatibility.scss

@@ -1,6 +1,7 @@
 @use '../../badge/badge-theme';
 @use '../../button/button-theme';
 @use '../../button/fab-theme';
+@use '../../button/icon-button-theme';
 @use '../../checkbox/checkbox-theme';
 @use '../../chips/chips-theme';
 @use '../../datepicker/datepicker-theme';
@@ -80,6 +81,7 @@ $_overrides-only: true;
 
   &.mat-mdc-button-base {
     @include button-theme.color($theme, $primary-options...);
+    @include icon-button-theme.color($theme, $primary-options...);
   }
 
   &.mat-mdc-standard-chip {

src/material/core/tokens/m3/mat/_icon-button.scss

@@ -11,7 +11,7 @@ $prefix: (mat, icon-button);
 /// @param {Map} $token-slots Possible token slots
 /// @return {Map} A set of custom tokens for the mat-icon-button
 @function get-tokens($systems, $exclude-hardcoded, $token-slots) {
-  $tokens: (
+  $tokens: ((
     state-layer-color: map.get($systems, md-sys-color, on-surface-variant),
     disabled-state-layer-color: map.get($systems, md-sys-color, on-surface-variant),
     ripple-color: sass-utils.safe-color-change(
@@ -21,7 +21,36 @@ $prefix: (mat, icon-button);
     hover-state-layer-opacity: map.get($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),
-  );
+  ), (
+    primary: (
+      state-layer-color: map.get($systems, md-sys-color, primary),
+      ripple-color: sass-utils.safe-color-change(
+        map.get($systems, md-sys-color, primary),
+        $alpha: map.get($systems, md-sys-state, pressed-state-layer-opacity)
+      ),
+    ),
+    secondary: (
+      state-layer-color: map.get($systems, md-sys-color, secondary),
+      ripple-color: sass-utils.safe-color-change(
+        map.get($systems, md-sys-color, secondary),
+        $alpha: map.get($systems, md-sys-state, pressed-state-layer-opacity)
+      ),
+    ),
+    tertiary: (
+      state-layer-color: map.get($systems, md-sys-color, tertiary),
+      ripple-color: sass-utils.safe-color-change(
+        map.get($systems, md-sys-color, tertiary),
+        $alpha: map.get($systems, md-sys-state, pressed-state-layer-opacity)
+      ),
+    ),
+    error: (
+      state-layer-color: map.get($systems, md-sys-color, error),
+      ripple-color: sass-utils.safe-color-change(
+        map.get($systems, md-sys-color, error),
+        $alpha: map.get($systems, md-sys-state, pressed-state-layer-opacity)
+      ),
+    )
+  ));
 
   @return token-utils.namespace-tokens($prefix, $tokens, $token-slots);
 }

src/material/core/tokens/m3/mdc/_icon-button.scss

@@ -1,3 +1,5 @@
+@use 'sass:map';
+@use 'sass:meta';
 @use '../../token-utils';
 
 // The prefix used to generate the fully qualified name for tokens in this file.
@@ -9,9 +11,26 @@ $prefix: (mdc, icon-button);
 /// @param {Map} $token-slots Possible token slots
 /// @return {Map} A set of tokens for the MDC icon-button
 @function get-tokens($systems, $exclude-hardcoded, $token-slots) {
-  $mdc-tokens: token-utils.get-mdc-tokens('icon-button', $systems, $exclude-hardcoded);
+  $tokens: token-utils.get-mdc-tokens('icon-button', $systems, $exclude-hardcoded);
+  $variant-tokens: (
+    primary: (
+      icon-color: map.get($systems, md-sys-color, primary)
+    ),
+    secondary: (
+      icon-color: map.get($systems, md-sys-color, secondary)
+    ),
+    tertiary: (
+      icon-color: map.get($systems, md-sys-color, tertiary)
+    ),
+    error: (
+      icon-color: map.get($systems, md-sys-color, error)
+    )
+  );
 
-  @return token-utils.namespace-tokens($prefix, _fix-tokens($mdc-tokens), $token-slots);
+  @return token-utils.namespace-tokens($prefix, (
+    _fix-tokens($tokens),
+    token-utils.map-values($variant-tokens, meta.get-function(_fix-tokens))
+  ), $token-slots);
 }
 
 /// Fixes inconsistent values in the icon button tokens so that they can produce valid styles.