feat: add shadow tag to minimessage, closes #1120

text-minimessage/src/main/java/net/kyori/adventure/text/minimessage/tag/standard/ShadowColorTagResolver.java

@@ -0,0 +1,49 @@
+package net.kyori.adventure.text.minimessage.tag.standard;
+
+import net.kyori.adventure.text.format.ShadowColor;
+import net.kyori.adventure.text.format.Style;
+import net.kyori.adventure.text.minimessage.Context;
+import net.kyori.adventure.text.minimessage.ParsingException;
+import net.kyori.adventure.text.minimessage.internal.serializer.SerializableResolver;
+import net.kyori.adventure.text.minimessage.internal.serializer.StyleClaim;
+import net.kyori.adventure.text.minimessage.tag.Tag;
+import net.kyori.adventure.text.minimessage.tag.resolver.ArgumentQueue;
+import net.kyori.adventure.text.minimessage.tag.resolver.TagResolver;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+class ShadowColorTagResolver implements TagResolver, SerializableResolver.Single {
+  private static final String SHADOW_COLOR = "shadow";
+
+  static final TagResolver INSTANCE = new ShadowColorTagResolver();
+  private static final StyleClaim<ShadowColor> STYLE = StyleClaim.claim(SHADOW_COLOR, Style::shadowColor, (color, emitter) -> {
+      emitter.tag(SHADOW_COLOR).argument(color.asHexString());
+  });
+
+  ShadowColorTagResolver() {
+  }
+
+  @Override
+  public @Nullable Tag resolve(final @NotNull String name, final @NotNull ArgumentQueue args, final @NotNull Context ctx) throws ParsingException {
+    if (!this.has(name)) {
+      return null;
+    }
+
+    final String colorString = args.popOr("Expected to find a color parameter: #RRGGBBAA").lowerValue();
+    final ShadowColor color = ShadowColor.fromHexString(colorString);
+    if (color == null) {
+      throw ctx.newException(String.format("Unable to parse a shadow color from '%s'. Please use #RRGGBBAA formatting.", colorString));
+    }
+    return Tag.styling(color);
+  }
+
+  @Override
+  public boolean has(final @NotNull String name) {
+    return name.equals(SHADOW_COLOR);
+  }
+
+  @Override
+  public @Nullable StyleClaim<?> claimStyle() {
+    return STYLE;
+  }
+}

text-minimessage/src/main/java/net/kyori/adventure/text/minimessage/tag/standard/StandardTags.java

@@ -64,7 +64,8 @@ private StandardTags() {
         SelectorTag.RESOLVER,
         ScoreTag.RESOLVER,
         NbtTag.RESOLVER,
-        PrideTag.RESOLVER
+        PrideTag.RESOLVER,
+        ShadowColorTagResolver.INSTANCE
       )
       .build();
 
@@ -275,6 +276,18 @@ public static TagResolver transition() {
     return PrideTag.RESOLVER;
   }
 
+  /**
+   * Get a resolver for the {@value ShadowColorTagResolver#SHADOW_COLOR} tags.
+   *
+   * <p>This tag support both hex string</p>
+   *
+   * @return a resolver for the {@value ShadowColorTagResolver#SHADOW_COLOR} tags
+   * @since 4.10.0
+   */
+  public static @NotNull TagResolver shadowColor() {
+    return ShadowColorTagResolver.INSTANCE;
+  }
+
   /**
    * Get a resolver that handles all default standard tags.
    *

text-minimessage/src/test/java/net/kyori/adventure/text/minimessage/tag/standard/ShadowTagTest.java

@@ -0,0 +1,31 @@
+package net.kyori.adventure.text.minimessage.tag.standard;
+
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.ShadowColor;
+import net.kyori.adventure.text.minimessage.AbstractTest;
+import org.junit.jupiter.api.Test;
+
+class ShadowTagTest extends AbstractTest {
+
+  @Test
+  void testSerializeShadow() {
+    final String expected = "<shadow:#054D79FF>This is a test";
+
+    final Component builder = Component.text("This is a test").shadowColor(ShadowColor.shadowColor(-16429703));
+
+    this.assertSerializedEquals(expected, builder);
+    this.assertParsedEquals(builder, expected);
+  }
+
+  @Test
+  void testSerializeShadowClosing() {
+    final String expected = "<shadow:#054D79FF>This is a</shadow> test";
+
+    final Component builder = Component.text()
+      .append(Component.text("This is a").shadowColor(ShadowColor.shadowColor(-16429703)))
+      .append(Component.text(" test")).asComponent();
+
+    this.assertSerializedEquals(expected, builder);
+    this.assertParsedEquals(builder, expected);
+  }
+}