Remove to it's own function.

Author: spacedmonkey

lib/experimental/class-wp-theme-json-resolver-gutenberg.php

@@ -65,40 +65,14 @@ public static function get_theme_data( $deprecated = array(), $settings = array(
 		if ( ! $settings['with_supports'] ) {
 			return static::$theme;
 		}
-		
-		$editor_settings = array(
-			'disableCustomColors'    => get_theme_support( 'disable-custom-colors' ),
-			'disableCustomFontSizes' => get_theme_support( 'disable-custom-font-sizes' ),
-			'disableCustomGradients' => get_theme_support( 'disable-custom-gradients' ),
-			'disableLayoutStyles'    => get_theme_support( 'disable-layout-styles' ),
-			'enableCustomLineHeight' => get_theme_support( 'custom-line-height' ),
-			'enableCustomSpacing'    => get_theme_support( 'custom-spacing' ),
-			'enableCustomUnits'      => get_theme_support( 'custom-units' ),
-		);
-
-		// Theme settings.
-		$color_palette = current( (array) get_theme_support( 'editor-color-palette' ) );
-		if ( false !== $color_palette ) {
-			$editor_settings['colors'] = $color_palette;
-		}
-
-		$font_sizes = current( (array) get_theme_support( 'editor-font-sizes' ) );
-		if ( false !== $font_sizes ) {
-			$editor_settings['fontSizes'] = $font_sizes;
-		}
-
-		$gradient_presets = current( (array) get_theme_support( 'editor-gradient-presets' ) );
-		if ( false !== $gradient_presets ) {
-			$editor_settings['gradients'] = $gradient_presets;
-		}
 
 		/*
 		 * We want the presets and settings declared in theme.json
 		 * to override the ones declared via theme supports.
 		 * So we take theme supports, transform it to theme.json shape
 		 * and merge the static::$theme upon that.
 		 */
-		$theme_support_data = WP_Theme_JSON_Gutenberg::get_from_editor_settings( $editor_settings );
+		$theme_support_data = WP_Theme_JSON_Gutenberg::get_from_editor_settings( gutenberg_get_block_theme_supports() );
 		if ( ! wp_theme_has_theme_json() ) {
 			if ( ! isset( $theme_support_data['settings']['color'] ) ) {
 				$theme_support_data['settings']['color'] = array();

lib/experimental/get-global-styles-and-settings.php

@@ -0,0 +1,38 @@
+<?php
+
+
+/**
+ * Repeated logic from `get_default_block_editor_settings` function. When implemented into core,
+ * remove logic from `get_default_block_editor_settings` and simple call this function instead.
+ *
+ * @return array
+ */
+function gutenberg_get_block_theme_supports(){
+	$theme_settings = array(
+		'disableCustomColors'    => get_theme_support( 'disable-custom-colors' ),
+		'disableCustomFontSizes' => get_theme_support( 'disable-custom-font-sizes' ),
+		'disableCustomGradients' => get_theme_support( 'disable-custom-gradients' ),
+		'disableLayoutStyles'    => get_theme_support( 'disable-layout-styles' ),
+		'enableCustomLineHeight' => get_theme_support( 'custom-line-height' ),
+		'enableCustomSpacing'    => get_theme_support( 'custom-spacing' ),
+		'enableCustomUnits'      => get_theme_support( 'custom-units' ),
+	);
+
+	// Theme settings.
+	$color_palette = current( (array) get_theme_support( 'editor-color-palette' ) );
+	if ( false !== $color_palette ) {
+		$theme_settings['colors'] = $color_palette;
+	}
+
+	$font_sizes = current( (array) get_theme_support( 'editor-font-sizes' ) );
+	if ( false !== $font_sizes ) {
+		$theme_settings['fontSizes'] = $font_sizes;
+	}
+
+	$gradient_presets = current( (array) get_theme_support( 'editor-gradient-presets' ) );
+	if ( false !== $gradient_presets ) {
+		$theme_settings['gradients'] = $gradient_presets;
+	}
+
+	return $theme_settings;
+}

lib/load.php

@@ -115,6 +115,7 @@ function gutenberg_is_experiment_enabled( $name ) {
 if ( ! class_exists( 'WP_HTML_Tag_Processor' ) ) {
 	require __DIR__ . '/experimental/html/index.php';
 }
+require __DIR__ . '/experimental/get-global-styles-and-settings.php';
 require __DIR__ . '/experimental/class-wp-theme-json-gutenberg.php';
 require __DIR__ . '/experimental/class-wp-theme-json-resolver-gutenberg.php';
 require __DIR__ . '/experimental/class-wp-webfonts.php';