Custom doctag extension (#2343)

* Add an extension point for rendering custom doc tags

* Iterate over documentable sourcesets when building custom tags

* Extract a nested custom tags brief block into a separate method

* Filter out tag content providers and make since kotlin brief a one-liner

* Add padding to "Since Kotlin" block in brief description

1 files changed, 23 insertions, 2 deletions

diff --git a/plugins/base/api/base.api b/plugins/base/api/base.api
index 488d2d8d..b17b4052 100644
--- a/plugins/base/api/base.api
+++ b/plugins/base/api/base.api
@@ -5,6 +5,7 @@ public final class org/jetbrains/dokka/base/DokkaBase : org/jetbrains/dokka/plug
 	public final fun getBaseSearchbarDataInstaller ()Lorg/jetbrains/dokka/plugability/Extension;
 	public final fun getCommentsToContentConverter ()Lorg/jetbrains/dokka/plugability/ExtensionPoint;
 	public final fun getCustomResourceInstaller ()Lorg/jetbrains/dokka/plugability/Extension;
+	public final fun getCustomTagContentProvider ()Lorg/jetbrains/dokka/plugability/ExtensionPoint;
 	public final fun getDefaultExternalClasslikesTranslator ()Lorg/jetbrains/dokka/plugability/Extension;
 	public final fun getDefaultExternalDocumentablesProvider ()Lorg/jetbrains/dokka/plugability/Extension;
 	public final fun getDefaultKotlinAnalysis ()Lorg/jetbrains/dokka/plugability/Extension;
@@ -52,6 +53,7 @@ public final class org/jetbrains/dokka/base/DokkaBase : org/jetbrains/dokka/plug
 	public final fun getSameMethodNameMerger ()Lorg/jetbrains/dokka/plugability/Extension;
 	public final fun getScriptsInstaller ()Lorg/jetbrains/dokka/plugability/Extension;
 	public final fun getSignatureProvider ()Lorg/jetbrains/dokka/plugability/ExtensionPoint;
+	public final fun getSinceKotlinTagContentProvider ()Lorg/jetbrains/dokka/plugability/Extension;
 	public final fun getSinceKotlinTransformer ()Lorg/jetbrains/dokka/plugability/Extension;
 	public final fun getSingleGeneration ()Lorg/jetbrains/dokka/plugability/Extension;
 	public final fun getSourceLinksTransformer ()Lorg/jetbrains/dokka/plugability/Extension;
@@ -1267,6 +1269,24 @@ public final class org/jetbrains/dokka/base/transformers/pages/sourcelinks/Sourc
 	public static final fun hasTabbedContent (Lorg/jetbrains/dokka/pages/ContentGroup;)Z
 }
 
+public abstract interface class org/jetbrains/dokka/base/transformers/pages/tags/CustomTagContentProvider {
+	public abstract fun contentForBrief (Lorg/jetbrains/dokka/base/translators/documentables/PageContentBuilder$DocumentableContentBuilder;Lorg/jetbrains/dokka/DokkaConfiguration$DokkaSourceSet;Lorg/jetbrains/dokka/model/doc/CustomTagWrapper;)V
+	public abstract fun contentForDescription (Lorg/jetbrains/dokka/base/translators/documentables/PageContentBuilder$DocumentableContentBuilder;Lorg/jetbrains/dokka/DokkaConfiguration$DokkaSourceSet;Lorg/jetbrains/dokka/model/doc/CustomTagWrapper;)V
+	public abstract fun isApplicable (Lorg/jetbrains/dokka/model/doc/CustomTagWrapper;)Z
+}
+
+public final class org/jetbrains/dokka/base/transformers/pages/tags/CustomTagContentProvider$DefaultImpls {
+	public static fun contentForBrief (Lorg/jetbrains/dokka/base/transformers/pages/tags/CustomTagContentProvider;Lorg/jetbrains/dokka/base/translators/documentables/PageContentBuilder$DocumentableContentBuilder;Lorg/jetbrains/dokka/DokkaConfiguration$DokkaSourceSet;Lorg/jetbrains/dokka/model/doc/CustomTagWrapper;)V
+	public static fun contentForDescription (Lorg/jetbrains/dokka/base/transformers/pages/tags/CustomTagContentProvider;Lorg/jetbrains/dokka/base/translators/documentables/PageContentBuilder$DocumentableContentBuilder;Lorg/jetbrains/dokka/DokkaConfiguration$DokkaSourceSet;Lorg/jetbrains/dokka/model/doc/CustomTagWrapper;)V
+}
+
+public final class org/jetbrains/dokka/base/transformers/pages/tags/SinceKotlinTagContentProvider : org/jetbrains/dokka/base/transformers/pages/tags/CustomTagContentProvider {
+	public static final field INSTANCE Lorg/jetbrains/dokka/base/transformers/pages/tags/SinceKotlinTagContentProvider;
+	public fun contentForBrief (Lorg/jetbrains/dokka/base/translators/documentables/PageContentBuilder$DocumentableContentBuilder;Lorg/jetbrains/dokka/DokkaConfiguration$DokkaSourceSet;Lorg/jetbrains/dokka/model/doc/CustomTagWrapper;)V
+	public fun contentForDescription (Lorg/jetbrains/dokka/base/translators/documentables/PageContentBuilder$DocumentableContentBuilder;Lorg/jetbrains/dokka/DokkaConfiguration$DokkaSourceSet;Lorg/jetbrains/dokka/model/doc/CustomTagWrapper;)V
+	public fun isApplicable (Lorg/jetbrains/dokka/model/doc/CustomTagWrapper;)Z
+}
+
 public final class org/jetbrains/dokka/base/translators/descriptors/DRIWithPlatformInfo {
 	public fun <init> (Lorg/jetbrains/dokka/links/DRI;Ljava/util/Map;)V
 	public final fun component1 ()Lorg/jetbrains/dokka/links/DRI;
@@ -1319,7 +1339,8 @@ public final class org/jetbrains/dokka/base/translators/documentables/DefaultDoc
 }
 
 public class org/jetbrains/dokka/base/translators/documentables/DefaultPageCreator {
-	public fun <init> (Lorg/jetbrains/dokka/base/DokkaBaseConfiguration;Lorg/jetbrains/dokka/base/transformers/pages/comments/CommentsToContentConverter;Lorg/jetbrains/dokka/base/signatures/SignatureProvider;Lorg/jetbrains/dokka/utilities/DokkaLogger;)V
+	public fun <init> (Lorg/jetbrains/dokka/base/DokkaBaseConfiguration;Lorg/jetbrains/dokka/base/transformers/pages/comments/CommentsToContentConverter;Lorg/jetbrains/dokka/base/signatures/SignatureProvider;Lorg/jetbrains/dokka/utilities/DokkaLogger;Ljava/util/List;)V
+	public synthetic fun <init> (Lorg/jetbrains/dokka/base/DokkaBaseConfiguration;Lorg/jetbrains/dokka/base/transformers/pages/comments/CommentsToContentConverter;Lorg/jetbrains/dokka/base/signatures/SignatureProvider;Lorg/jetbrains/dokka/utilities/DokkaLogger;Ljava/util/List;ILkotlin/jvm/internal/DefaultConstructorMarker;)V
 	protected fun contentForBrief (Lorg/jetbrains/dokka/base/translators/documentables/PageContentBuilder$DocumentableContentBuilder;Lorg/jetbrains/dokka/model/Documentable;)V
 	protected fun contentForClasslike (Lorg/jetbrains/dokka/model/DClasslike;)Lorg/jetbrains/dokka/pages/ContentGroup;
 	protected fun contentForComments (Lorg/jetbrains/dokka/model/Documentable;Z)Ljava/util/List;
@@ -1332,10 +1353,10 @@ public class org/jetbrains/dokka/base/translators/documentables/DefaultPageCreat
 	protected fun contentForPackage (Lorg/jetbrains/dokka/model/DPackage;)Lorg/jetbrains/dokka/pages/ContentGroup;
 	protected fun contentForProperty (Lorg/jetbrains/dokka/model/DProperty;)Lorg/jetbrains/dokka/pages/ContentGroup;
 	protected fun contentForScope (Lorg/jetbrains/dokka/model/WithScope;Lorg/jetbrains/dokka/links/DRI;Ljava/util/Set;)Lorg/jetbrains/dokka/pages/ContentGroup;
-	protected fun contentForSinceKotlin (Lorg/jetbrains/dokka/base/translators/documentables/PageContentBuilder$DocumentableContentBuilder;Lorg/jetbrains/dokka/model/Documentable;)V
 	protected fun divergentBlock (Lorg/jetbrains/dokka/base/translators/documentables/PageContentBuilder$DocumentableContentBuilder;Ljava/lang/String;Ljava/util/Collection;Lorg/jetbrains/dokka/pages/ContentKind;Lorg/jetbrains/dokka/model/properties/PropertyContainer;)V
 	public static synthetic fun divergentBlock$default (Lorg/jetbrains/dokka/base/translators/documentables/DefaultPageCreator;Lorg/jetbrains/dokka/base/translators/documentables/PageContentBuilder$DocumentableContentBuilder;Ljava/lang/String;Ljava/util/Collection;Lorg/jetbrains/dokka/pages/ContentKind;Lorg/jetbrains/dokka/model/properties/PropertyContainer;ILjava/lang/Object;)V
 	protected fun getContentBuilder ()Lorg/jetbrains/dokka/base/translators/documentables/PageContentBuilder;
+	public final fun getCustomTagContentProviders ()Ljava/util/List;
 	public final fun getLogger ()Lorg/jetbrains/dokka/utilities/DokkaLogger;
 	protected final fun getSeparateInheritedMembers ()Z
 	public fun pageForClasslike (Lorg/jetbrains/dokka/model/DClasslike;)Lorg/jetbrains/dokka/pages/ClasslikePageNode;