Integrate adocfmt for AsciiDoc formatting

CHANGES.md

@@ -10,6 +10,8 @@ This document is intended for Spotless developers.
 We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (starting after version `1.27.0`).
 
 ## [Unreleased]
+### Added
+- Add support for AsciiDoc formatting via `adocfmt`. ([#2960](https://github.com/diffplug/spotless/pull/2960))
 ### Fixed
 - Support `ktfmt` 0.63 and use its new builder API for formatting options to better avoid future breaking changes.
 ### Changes

lib/src/main/java/com/diffplug/spotless/asciidoc/AdocfmtConfig.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright 2026 DiffPlug
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.diffplug.spotless.asciidoc;
+
+import java.io.Serial;
+import java.io.Serializable;
+import java.util.Objects;
+
+public class AdocfmtConfig implements Serializable {
+	@Serial
+	private static final long serialVersionUID = 1L;
+
+	public boolean normalizeSetextHeadings = false;
+	public boolean collapseConsecutiveBlankLines = true;
+	public boolean oneSentencePerLine = false;
+	public boolean normalizeBlockDelimiters = true;
+	public boolean removeTrailingHeaderEqualsSign = true;
+	public boolean titleCase = false;
+	public boolean removeTrailingWhitespace = true;
+	public boolean normalizeListBullets = false;
+	public boolean normalizeOrderedListMarkers = false;
+	public boolean ensureHeadingBlankLines = true;
+	public boolean ensureSourceDelimiters = false;
+
+	public AdocfmtConfig() {}
+
+	@Override
+	public boolean equals(Object o) {
+		if (this == o)
+			return true;
+		if (!(o instanceof AdocfmtConfig other))
+			return false;
+		return normalizeSetextHeadings == other.normalizeSetextHeadings
+				&& collapseConsecutiveBlankLines == other.collapseConsecutiveBlankLines
+				&& oneSentencePerLine == other.oneSentencePerLine
+				&& normalizeBlockDelimiters == other.normalizeBlockDelimiters
+				&& removeTrailingHeaderEqualsSign == other.removeTrailingHeaderEqualsSign
+				&& titleCase == other.titleCase
+				&& removeTrailingWhitespace == other.removeTrailingWhitespace
+				&& normalizeListBullets == other.normalizeListBullets
+				&& normalizeOrderedListMarkers == other.normalizeOrderedListMarkers
+				&& ensureHeadingBlankLines == other.ensureHeadingBlankLines
+				&& ensureSourceDelimiters == other.ensureSourceDelimiters;
+	}
+
+	@Override
+	public int hashCode() {
+		return Objects.hash(normalizeSetextHeadings, collapseConsecutiveBlankLines, oneSentencePerLine,
+				normalizeBlockDelimiters, removeTrailingHeaderEqualsSign, titleCase, removeTrailingWhitespace,
+				normalizeListBullets, normalizeOrderedListMarkers, ensureHeadingBlankLines, ensureSourceDelimiters);
+	}
+}

lib/src/main/java/com/diffplug/spotless/asciidoc/AdocfmtStep.java

@@ -0,0 +1,117 @@
+/*
+ * Copyright 2026 DiffPlug
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.diffplug.spotless.asciidoc;
+
+import java.io.Serial;
+import java.io.Serializable;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.Objects;
+
+import com.diffplug.spotless.FormatterFunc;
+import com.diffplug.spotless.FormatterStep;
+import com.diffplug.spotless.JarState;
+import com.diffplug.spotless.Provisioner;
+import com.diffplug.spotless.ThrowingEx;
+
+public final class AdocfmtStep implements Serializable {
+	@Serial
+	private static final long serialVersionUID = 1L;
+	private static final String DEFAULT_VERSION = "0.2.0";
+	private static final String NAME = "adocfmt";
+	private static final String MAVEN_COORDINATE = "org.drjekyll:adocfmt:";
+
+	private final String version;
+	private final AdocfmtConfig config;
+	private final JarState.Promised jarState;
+
+	private AdocfmtStep(String version, AdocfmtConfig config, JarState.Promised jarState) {
+		this.version = version;
+		this.config = config;
+		this.jarState = jarState;
+	}
+
+	public static FormatterStep create(Provisioner provisioner) {
+		return create(defaultVersion(), provisioner);
+	}
+
+	public static FormatterStep create(String version, Provisioner provisioner) {
+		return create(version, provisioner, new AdocfmtConfig());
+	}
+
+	public static FormatterStep create(String version, Provisioner provisioner, AdocfmtConfig config) {
+		Objects.requireNonNull(version, "version");
+		Objects.requireNonNull(provisioner, "provisioner");
+		Objects.requireNonNull(config, "config");
+		return FormatterStep.create(NAME,
+				new AdocfmtStep(version, config, JarState.promise(() -> JarState.from(MAVEN_COORDINATE + version, provisioner))),
+				AdocfmtStep::equalityState,
+				State::createFormat);
+	}
+
+	public static String defaultVersion() {
+		return DEFAULT_VERSION;
+	}
+
+	private State equalityState() {
+		return new State(version, config, jarState.get());
+	}
+
+	private static final class State implements Serializable {
+		@Serial
+		private static final long serialVersionUID = 1L;
+		private final String version;
+		private final AdocfmtConfig config;
+		private final JarState jarState;
+
+		State(String version, AdocfmtConfig config, JarState jarState) {
+			this.version = version;
+			this.config = config;
+			this.jarState = jarState;
+		}
+
+		FormatterFunc createFormat() throws Exception {
+			final ClassLoader classLoader = jarState.getClassLoader();
+			final Class<?> formatterClass = classLoader.loadClass("org.drjekyll.adocfmt.AsciidocFormatter");
+			final Class<?> configClass = classLoader.loadClass("org.drjekyll.adocfmt.AsciidocFormatterConfig");
+			final Method builderMethod = configClass.getMethod("builder");
+			Object builder = builderMethod.invoke(null);
+			final Class<?> builderClass = builder.getClass();
+			builder = builderClass.getMethod("normalizeSetextHeadings", boolean.class).invoke(builder, config.normalizeSetextHeadings);
+			builder = builderClass.getMethod("collapseConsecutiveBlankLines", boolean.class).invoke(builder, config.collapseConsecutiveBlankLines);
+			builder = builderClass.getMethod("oneSentencePerLine", boolean.class).invoke(builder, config.oneSentencePerLine);
+			builder = builderClass.getMethod("normalizeBlockDelimiters", boolean.class).invoke(builder, config.normalizeBlockDelimiters);
+			builder = builderClass.getMethod("removeTrailingHeaderEqualsSign", boolean.class).invoke(builder, config.removeTrailingHeaderEqualsSign);
+			builder = builderClass.getMethod("titleCase", boolean.class).invoke(builder, config.titleCase);
+			builder = builderClass.getMethod("removeTrailingWhitespace", boolean.class).invoke(builder, config.removeTrailingWhitespace);
+			builder = builderClass.getMethod("normalizeListBullets", boolean.class).invoke(builder, config.normalizeListBullets);
+			builder = builderClass.getMethod("normalizeOrderedListMarkers", boolean.class).invoke(builder, config.normalizeOrderedListMarkers);
+			builder = builderClass.getMethod("ensureHeadingBlankLines", boolean.class).invoke(builder, config.ensureHeadingBlankLines);
+			builder = builderClass.getMethod("ensureSourceDelimiters", boolean.class).invoke(builder, config.ensureSourceDelimiters);
+			final Object adocfmtConfig = builderClass.getMethod("build").invoke(builder);
+
+			final Object formatter = formatterClass.getConstructor(configClass).newInstance(adocfmtConfig);
+			final Method formatMethod = formatterClass.getMethod("format", String.class);
+			return input -> {
+				try {
+					return (String) formatMethod.invoke(formatter, input);
+				} catch (InvocationTargetException e) {
+					throw ThrowingEx.unwrapCause(e);
+				}
+			};
+		}
+	}
+}

plugin-gradle/CHANGES.md

@@ -4,6 +4,8 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 
 ## [Unreleased]
 
+### Added
+- Add support for AsciiDoc formatting via `adocfmt`. ([#2960](https://github.com/diffplug/spotless/pull/2960))
 ### Fixed
 - Prevent build caches from interfering when executing under the `-PspotlessIdeHook` mode. ([#2365](https://github.com/diffplug/spotless/issues/2365))
 ### Changes

plugin-gradle/README.md

@@ -60,6 +60,7 @@ Spotless supports all of Gradle's built-in performance features (incremental bui
   - [Groovy](#groovy) ([eclipse groovy](#eclipse-groovy))
   - [Kotlin](#kotlin) ([ktfmt](#ktfmt), [ktlint](#ktlint), [diktat](#diktat), [tabletest-formatter](#tabletest-formatter-1), [prettier](#prettier))
   - [Scala](#scala) ([scalafmt](#scalafmt))
+  - [Asciidoc](#asciidoc) ([adocfmt](#adocfmt))
   - [C/C++](#cc) ([clang-format](#clang-format), [eclipse cdt](#eclipse-cdt))
   - [Protobuf](#protobuf) ([buf](#buf), [clang-format](#clang-format))
   - [Python](#python) ([black](#black))
@@ -830,6 +831,41 @@ spotless {
 antlr4formatter('1.2.1') // version is optional
 ```
 
+## Asciidoc
+
+`com.diffplug.gradle.spotless.AsciidocExtension` [javadoc](https://javadoc.io/doc/com.diffplug.spotless/spotless-plugin-gradle/8.6.0/com/diffplug/gradle/spotless/AsciidocExtension.html), [code](https://github.com/diffplug/spotless/blob/main/plugin-gradle/src/main/java/com/diffplug/gradle/spotless/AsciidocExtension.java)
+
+```gradle
+spotless {
+  asciidoc {
+    target 'src/docs/**/*.adoc' // you have to set the target manually
+
+    adocfmt() // has its own section below
+  }
+}
+```
+
+### adocfmt
+
+[homepage](https://github.com/dheid/adocfmt). [available versions](https://search.maven.org/artifact/org.drjekyll/adocfmt).
+
+```gradle
+adocfmt('0.2.0') // version is optional
+  .normalizeSetextHeadings(false)       // convert === underlines to ATX == (default: false)
+  .collapseConsecutiveBlankLines(true)  // max 1 blank line (default: true)
+  .oneSentencePerLine(false)            // each sentence on its own line (default: false)
+  .normalizeBlockDelimiters(true)       // exactly 4 characters (e.g. ----) (default: true)
+  .removeTrailingHeaderEqualsSign(true) // == Title == -> == Title (default: true)
+  .titleCase(false)                     // Title Case headings (default: false)
+  .removeTrailingWhitespace(true)       // trim end of line (default: true)
+  .normalizeListBullets(false)          // - -> * (default: false)
+  .normalizeOrderedListMarkers(false)   // 1. -> . (default: false)
+  .ensureHeadingBlankLines(true)        // blank line before/after headings (default: true)
+  .ensureSourceDelimiters(false)        // wrap [source] in ---- (default: false)
+```
+
+Options default to `true` or `false` as shown above. This formatter is designed to help you maintain a clean, consistent AsciiDoc structure. Surface-altering options like `oneSentencePerLine` and `normalizeSetextHeadings` default to `false` so that zero-config formatting is conservative; opt in explicitly if you want those transforms.
+
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plugin-gradle/src/main/java/com/diffplug/gradle/spotless/AsciidocExtension.java

@@ -0,0 +1,122 @@
+/*
+ * Copyright 2026 DiffPlug
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.diffplug.gradle.spotless;
+
+import javax.inject.Inject;
+
+import com.diffplug.spotless.asciidoc.AdocfmtConfig;
+import com.diffplug.spotless.asciidoc.AdocfmtStep;
+
+public class AsciidocExtension extends FormatExtension {
+	static final String NAME = "asciidoc";
+
+	@Inject
+	public AsciidocExtension(SpotlessExtension spotless) {
+		super(spotless);
+	}
+
+	public AdocfmtFormatterConfig adocfmt() {
+		return adocfmt(AdocfmtStep.defaultVersion());
+	}
+
+	public AdocfmtFormatterConfig adocfmt(String version) {
+		return new AdocfmtFormatterConfig(version);
+	}
+
+	public class AdocfmtFormatterConfig {
+		private final String version;
+		private final AdocfmtConfig config = new AdocfmtConfig();
+
+		AdocfmtFormatterConfig(String version) {
+			this.version = version;
+			addStep(AdocfmtStep.create(version, provisioner(), config));
+		}
+
+		public AdocfmtFormatterConfig normalizeSetextHeadings(boolean normalizeSetextHeadings) {
+			config.normalizeSetextHeadings = normalizeSetextHeadings;
+			replaceStep(AdocfmtStep.create(version, provisioner(), config));
+			return this;
+		}
+
+		public AdocfmtFormatterConfig collapseConsecutiveBlankLines(boolean collapseConsecutiveBlankLines) {
+			config.collapseConsecutiveBlankLines = collapseConsecutiveBlankLines;
+			replaceStep(AdocfmtStep.create(version, provisioner(), config));
+			return this;
+		}
+
+		public AdocfmtFormatterConfig oneSentencePerLine(boolean oneSentencePerLine) {
+			config.oneSentencePerLine = oneSentencePerLine;
+			replaceStep(AdocfmtStep.create(version, provisioner(), config));
+			return this;
+		}
+
+		public AdocfmtFormatterConfig normalizeBlockDelimiters(boolean normalizeBlockDelimiters) {
+			config.normalizeBlockDelimiters = normalizeBlockDelimiters;
+			replaceStep(AdocfmtStep.create(version, provisioner(), config));
+			return this;
+		}
+
+		public AdocfmtFormatterConfig removeTrailingHeaderEqualsSign(boolean removeTrailingHeaderEqualsSign) {
+			config.removeTrailingHeaderEqualsSign = removeTrailingHeaderEqualsSign;
+			replaceStep(AdocfmtStep.create(version, provisioner(), config));
+			return this;
+		}
+
+		public AdocfmtFormatterConfig titleCase(boolean titleCase) {
+			config.titleCase = titleCase;
+			replaceStep(AdocfmtStep.create(version, provisioner(), config));
+			return this;
+		}
+
+		public AdocfmtFormatterConfig removeTrailingWhitespace(boolean removeTrailingWhitespace) {
+			config.removeTrailingWhitespace = removeTrailingWhitespace;
+			replaceStep(AdocfmtStep.create(version, provisioner(), config));
+			return this;
+		}
+
+		public AdocfmtFormatterConfig normalizeListBullets(boolean normalizeListBullets) {
+			config.normalizeListBullets = normalizeListBullets;
+			replaceStep(AdocfmtStep.create(version, provisioner(), config));
+			return this;
+		}
+
+		public AdocfmtFormatterConfig normalizeOrderedListMarkers(boolean normalizeOrderedListMarkers) {
+			config.normalizeOrderedListMarkers = normalizeOrderedListMarkers;
+			replaceStep(AdocfmtStep.create(version, provisioner(), config));
+			return this;
+		}
+
+		public AdocfmtFormatterConfig ensureHeadingBlankLines(boolean ensureHeadingBlankLines) {
+			config.ensureHeadingBlankLines = ensureHeadingBlankLines;
+			replaceStep(AdocfmtStep.create(version, provisioner(), config));
+			return this;
+		}
+
+		public AdocfmtFormatterConfig ensureSourceDelimiters(boolean ensureSourceDelimiters) {
+			config.ensureSourceDelimiters = ensureSourceDelimiters;
+			replaceStep(AdocfmtStep.create(version, provisioner(), config));
+			return this;
+		}
+	}
+
+	@Override
+	protected void setupTask(SpotlessTask task) {
+		if (target == null) {
+			throw noDefaultTargetException();
+		}
+		super.setupTask(task);
+	}
+}

plugin-gradle/src/main/java/com/diffplug/gradle/spotless/SpotlessExtension.java

@@ -234,6 +234,12 @@ public void gherkin(Action<GherkinExtension> closure) {
 		format(GherkinExtension.NAME, GherkinExtension.class, closure);
 	}
 
+	/** Configures the special asciidoc-specific extension. */
+	public void asciidoc(Action<AsciidocExtension> closure) {
+		requireNonNull(closure);
+		format(AsciidocExtension.NAME, AsciidocExtension.class, closure);
+	}
+
 	public void toml(Action<TomlExtension> closure) {
 		requireNonNull(closure);
 		format(TomlExtension.NAME, TomlExtension.class, closure);