Add an autolink extension for Markdown (#341)

Exposes the autolink extension offered by the commonmark java library,
to markdown rendering in Compose. Since links are already supported
for processing and rendering, we only need to hookup the
parserExtension to get this to work.

gradle/libs.versions.toml

@@ -16,6 +16,7 @@ poko = "0.13.1"
 
 [libraries]
 commonmark-core = { module = "org.commonmark:commonmark", version.ref = "commonmark" }
+commonmark-ext-autolink = { module = "org.commonmark:commonmark-ext-autolink", version.ref = "commonmark" }
 
 filePicker = { module = "com.darkrockstudios:mpfilepicker", version = "3.1.0" }
 

markdown/core/src/main/kotlin/org/jetbrains/jewel/markdown/extensions/MarkdownProcessorExtension.kt

@@ -9,25 +9,28 @@ import org.jetbrains.jewel.markdown.MarkdownBlock
 /** An extension for the Jewel Markdown processing engine. */
 @ExperimentalJewelApi
 public interface MarkdownProcessorExtension {
-
     /**
      * A CommonMark [ParserExtension] that will be used to parse the extended
-     * syntax represented by this extension instance.
+     * syntax represented by this extension instance. Null in the case where
+     * parsing is already handled by an existing [org.commonmark.parser.Parser].
      */
-    public val parserExtension: ParserExtension
+    public val parserExtension: ParserExtension?
 
     /**
      * A CommonMark [TextContentRendererExtension] that will be used to render
      * the text content of the CommonMark [CustomBlock] produced by the
-     * [parserExtension].
+     * [parserExtension]. Null in the case where rendering is already
+     * handled by an existing [org.commonmark.renderer.Renderer].
      */
-    public val textRendererExtension: TextContentRendererExtension
+    public val textRendererExtension: TextContentRendererExtension?
 
     /**
      * An extension for
      * [`MarkdownParser`][org.jetbrains.jewel.markdown.parsing.MarkdownParser]
      * that will transform a supported [CustomBlock] into the corresponding
-     * [MarkdownBlock.CustomBlock].
+     * [MarkdownBlock.CustomBlock]. Null in the case where processing
+     * is already be handled by [org.jetbrains.jewel.markdown.processing.MarkdownProcessor]
+     * or another [org.jetbrains.jewel.markdown.extensions.MarkdownProcessorExtension].
      */
-    public val processorExtension: MarkdownBlockProcessorExtension
+    public val processorExtension: MarkdownBlockProcessorExtension?
 }

markdown/core/src/main/kotlin/org/jetbrains/jewel/markdown/processing/MarkdownProcessor.kt

@@ -189,7 +189,7 @@ public class MarkdownProcessor(
             is ThematicBreak -> MarkdownBlock.ThematicBreak
             is HtmlBlock -> toMarkdownHtmlBlockOrNull()
             is CustomBlock -> {
-                extensions.find { it.processorExtension.canProcess(this) }
+                extensions.find { it.processorExtension?.canProcess(this) == true }
                     ?.processorExtension?.processMarkdownBlock(this, this@MarkdownProcessor)
             }
             else -> null

markdown/extension/autolink/api/autolink.api

@@ -0,0 +1,8 @@
+public final class org/jetbrains/jewel/markdown/extension/autolink/AutolinkProcessorExtension : org/jetbrains/jewel/markdown/extensions/MarkdownProcessorExtension {
+	public static final field $stable I
+	public static final field INSTANCE Lorg/jetbrains/jewel/markdown/extension/autolink/AutolinkProcessorExtension;
+	public fun getParserExtension ()Lorg/commonmark/parser/Parser$ParserExtension;
+	public fun getProcessorExtension ()Lorg/jetbrains/jewel/markdown/extensions/MarkdownBlockProcessorExtension;
+	public fun getTextRendererExtension ()Lorg/commonmark/renderer/text/TextContentRenderer$TextContentRendererExtension;
+}
+

markdown/extension/autolink/build.gradle.kts

@@ -0,0 +1,17 @@
+plugins {
+    jewel
+    `jewel-publish`
+    `jewel-check-public-api`
+    alias(libs.plugins.composeDesktop)
+}
+
+dependencies {
+    implementation(projects.markdown.core)
+    implementation(libs.commonmark.ext.autolink)
+    testImplementation(compose.desktop.uiTestJUnit4)
+}
+
+publishing.publications.named<MavenPublication>("main") {
+    val ijpTarget = project.property("ijp.target") as String
+    artifactId = "jewel-markdown-extension-${project.name}-$ijpTarget"
+}

markdown/extension/autolink/src/main/kotlin/org/jetbrains/jewel/markdown/extension/autolink/AutolinkProcessorExtension.kt

@@ -0,0 +1,20 @@
+package org.jetbrains.jewel.markdown.extension.autolink
+
+import org.commonmark.ext.autolink.AutolinkExtension
+import org.commonmark.parser.Parser.ParserExtension
+import org.commonmark.renderer.text.TextContentRenderer
+import org.jetbrains.jewel.markdown.extensions.MarkdownBlockProcessorExtension
+import org.jetbrains.jewel.markdown.extensions.MarkdownProcessorExtension
+
+public object AutolinkProcessorExtension : MarkdownProcessorExtension {
+    override val parserExtension: ParserExtension
+        get() = AutolinkExtension.create() as ParserExtension
+
+    /**
+     * Rendering and processing is already handled by [org.jetbrains.jewel.markdown.rendering.DefaultInlineMarkdownRenderer]
+     */
+    override val textRendererExtension: TextContentRenderer.TextContentRendererExtension?
+        get() = null
+    override val processorExtension: MarkdownBlockProcessorExtension?
+        get() = null
+}

markdown/extension/autolink/src/test/kotlin/org/jetbrains/jewel/markdown/extension/autolink/AutolinkProcessorExtensionTest.kt

@@ -0,0 +1,20 @@
+package org.jetbrains.jewel.markdown.extension.autolink
+
+import org.jetbrains.jewel.markdown.InlineMarkdown
+import org.jetbrains.jewel.markdown.MarkdownBlock
+import org.jetbrains.jewel.markdown.processing.MarkdownProcessor
+import org.junit.Assert.assertTrue
+import org.junit.Test
+
+class AutolinkProcessorExtensionTest {
+    // testing a simple case to assure wiring up our AutolinkProcessorExtension works correctly
+    @Test
+    fun `https text gets processed into a link`() {
+        val processor = MarkdownProcessor(listOf(AutolinkProcessorExtension))
+        val rawMarkDown = "https://commonmark.org"
+        val processed = processor.processMarkdownDocument(rawMarkDown)
+        val paragraph = processed[0] as MarkdownBlock.Paragraph
+
+        assertTrue(paragraph.inlineContent[0] is InlineMarkdown.Link)
+    }
+}

samples/standalone/build.gradle.kts

@@ -14,7 +14,7 @@ dependencies {
     implementation(projects.intUi.intUiDecoratedWindow)
     implementation(projects.markdown.intUiStandaloneStyling)
     implementation(projects.markdown.extension.gfmAlerts)
-
+    implementation(projects.markdown.extension.autolink)
     implementation(compose.desktop.currentOs) {
         exclude(group = "org.jetbrains.compose.material")
     }

samples/standalone/src/main/kotlin/org/jetbrains/jewel/samples/standalone/view/markdown/MarkdownPreview.kt

@@ -31,6 +31,7 @@ import org.jetbrains.jewel.intui.markdown.styling.extension.github.alerts.dark
 import org.jetbrains.jewel.intui.markdown.styling.extension.github.alerts.light
 import org.jetbrains.jewel.intui.markdown.styling.light
 import org.jetbrains.jewel.markdown.MarkdownBlock
+import org.jetbrains.jewel.markdown.extension.autolink.AutolinkProcessorExtension
 import org.jetbrains.jewel.markdown.extensions.github.alerts.AlertStyling
 import org.jetbrains.jewel.markdown.extensions.github.alerts.GitHubAlertProcessorExtension
 import org.jetbrains.jewel.markdown.extensions.github.alerts.GitHubAlertRendererExtension
@@ -43,14 +44,17 @@ import java.awt.Desktop
 import java.net.URI
 
 @Composable
-internal fun MarkdownPreview(rawMarkdown: String, modifier: Modifier = Modifier) {
+internal fun MarkdownPreview(
+    rawMarkdown: String,
+    modifier: Modifier = Modifier,
+) {
     val isDark = JewelTheme.isDark
 
     val markdownStyling =
         remember(isDark) { if (isDark) MarkdownStyling.dark() else MarkdownStyling.light() }
 
     var markdownBlocks by remember { mutableStateOf(emptyList<MarkdownBlock>()) }
-    val extensions = listOf(GitHubAlertProcessorExtension)
+    val extensions = listOf(GitHubAlertProcessorExtension, AutolinkProcessorExtension)
     val processor = remember { MarkdownProcessor(extensions) }
 
     LaunchedEffect(rawMarkdown) {

settings.gradle.kts

@@ -36,6 +36,7 @@ include(
     ":int-ui:int-ui-decorated-window",
     ":int-ui:int-ui-standalone",
     ":markdown:core",
+    ":markdown:extension:autolink",
     ":markdown:extension:gfm-alerts",
     ":markdown:int-ui-standalone-styling",
     ":markdown:ide-laf-bridge-styling",