feat(typography): implement resolve-tokens function to use -text-type

PiperOrigin-RevId: 509590749

sass/_typography.scss

@@ -12,6 +12,37 @@
 @use './theme';
 // go/keep-sorted end
 
+/// Resolves a theme's typography tokens for the given prefixes
+///
+/// @example - scss
+///   // $theme has the following tokens:
+///   // - label-text-font
+///   // - label-text-line-height
+///   // - label-text-size
+///   // - label-text-tracking
+///   // - label-text-weight
+///   // - label-text-type
+///   @debug resolve-tokens($theme, label-text); // (label-text-type: ...)
+///
+/// @param {Map} $tokens - Tokens to resolve
+/// @param {String...} $token-prefixes - The prefixes of typography tokens to resolve.
+/// @return {Map} The resolved tokens
+@function resolve-tokens($tokens, $token-prefixes...) {
+  @each $token-prefix in $token-prefixes {
+    // leave only `#{$token-prefix}-type`
+    $tokens: map.remove(
+      $tokens,
+      '#{$token-prefix}-font',
+      '#{$token-prefix}-line-height',
+      '#{$token-prefix}-size',
+      '#{$token-prefix}-tracking',
+      '#{$token-prefix}-weight'
+    );
+  }
+
+  @return $tokens;
+}
+
 /// Resolves a theme's typography tokens for the given prefix.
 ///
 /// @example - scss

sass/test/_typography.test.scss

@@ -0,0 +1,56 @@
+//
+// Copyright 2023 Google LLC
+// SPDX-License-Identifier: Apache-2.0
+//
+
+// go/keep-sorted start
+@use 'sass:map';
+@use 'sass:meta';
+@use 'true' as test;
+// go/keep-sorted end
+// go/keep-sorted start
+@use '../map-ext';
+@use '../typography';
+// go/keep-sorted end
+
+@include test.describe('typography') {
+  $input: (
+    'text-font': 'Roboto',
+    'text-line-height': 1rem,
+    'text-size': 1rem,
+    'text-tracking': 0.005rem,
+    'text-weight': 400,
+    'text-type': '400 1rem/1rem Roboto',
+  );
+
+  @include test.describe('resolve-tokens()') {
+    @include test.it('should return a map') {
+      $result: typography.resolve-tokens($input);
+      @include test.assert-equal(meta.type-of($result), 'map');
+    }
+
+    @include test.it('does not modify input without a list of tokens') {
+      $expected: $input;
+      $result: typography.resolve-tokens($input);
+      @include test.assert-equal($expected, $result);
+    }
+
+    @include test.it('should remove typography tokens aside from `-type`') {
+      $expected: map-ext.pick($input, ('text-type'));
+      $result: typography.resolve-tokens($input, 'text');
+      @include test.assert-equal($expected, $result);
+    }
+
+    @include test.it('only modifies specified tokens') {
+      $input: map.merge(
+        $input,
+        (
+          'other-token': 16px,
+        )
+      );
+      $expected: map-ext.pick($input, ('text-type', 'other-token'));
+      $result: typography.resolve-tokens($input, 'text');
+      @include test.assert-equal($expected, $result);
+    }
+  }
+}

sass/test/test.scss

@@ -9,4 +9,5 @@
 @use './map-ext.test';
 @use './shape.test';
 @use './string-ext.test';
+@use './typography.test';
 // go/keep-sorted end