Add support for gherkin (#1649)

Author: nedtwigg

.editorconfig

@@ -25,3 +25,13 @@ indent_style = space
 [*.{yml,yaml}]
 indent_style = space
 indent_size = 2
+
+# Prevent unexpected automatic indentation when crafting test-cases
+[/testlib/src/main/resources/**]
+charset = unset
+end_of_line = unset
+insert_final_newline = unset
+trim_trailing_whitespace = unset
+indent_style = unset
+indent_size = unset
+ij_formatter_enabled = false

CHANGES.md

@@ -13,6 +13,7 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 ### Added
 * Support configuration of mirrors for P2 repositories in `EquoBasedStepBuilder` ([#1629](https://github.com/diffplug/spotless/issues/1629)).
 * The `style` option in Palantir Java Format ([#1654](https://github.com/diffplug/spotless/pull/1654)).
+* Added formatter for Gherkin feature files ([#1649](https://github.com/diffplug/spotless/issues/1649)).
 ### Changes
 * **POTENTIALLY BREAKING** Converted `googleJavaFormat` to a compile-only dependency and drop support for versions < `1.8`. ([#1630](https://github.com/diffplug/spotless/pull/1630))
 * Bump default `googleJavaFormat` version `1.15.0` -> `1.16.0`. ([#1630](https://github.com/diffplug/spotless/pull/1630))

README.md

@@ -77,6 +77,7 @@ lib('generic.TrimTrailingWhitespaceStep')        +'{{yes}}       | {{yes}}
 lib('antlr4.Antlr4FormatterStep')                +'{{yes}}       | {{yes}}      | {{no}}       | {{no}}  |',
 lib('cpp.ClangFormatStep')                       +'{{yes}}       | {{no}}       | {{no}}       | {{no}}  |',
 extra('cpp.EclipseFormatterStep')                +'{{yes}}       | {{yes}}      | {{yes}}      | {{no}}  |',
+lib('gherkin.GherkinUtilsStep')                  +'{{yes}}       | {{yes}}      | {{no}}       | {{no}}  |',
 extra('groovy.GrEclipseFormatterStep')           +'{{yes}}       | {{yes}}      | {{yes}}      | {{no}}  |',
 lib('java.GoogleJavaFormatStep')                 +'{{yes}}       | {{yes}}      | {{yes}}      | {{no}}  |',
 lib('java.ImportOrderStep')                      +'{{yes}}       | {{yes}}      | {{yes}}      | {{no}}  |',
@@ -125,6 +126,7 @@ lib('yaml.JacksonYamlStep')                      +'{{yes}}       | {{yes}}
 | [`antlr4.Antlr4FormatterStep`](lib/src/main/java/com/diffplug/spotless/antlr4/Antlr4FormatterStep.java) | :+1:       | :+1:      | :white_large_square:       | :white_large_square:  |
 | [`cpp.ClangFormatStep`](lib/src/main/java/com/diffplug/spotless/cpp/ClangFormatStep.java) | :+1:       | :white_large_square:       | :white_large_square:       | :white_large_square:  |
 | [`cpp.EclipseFormatterStep`](lib-extra/src/main/java/com/diffplug/spotless/extra/cpp/EclipseFormatterStep.java) | :+1:       | :+1:      | :+1:      | :white_large_square:  |
+| [`gherkin.GherkinUtilsStep`](lib/src/main/java/com/diffplug/spotless/gherkin/GherkinUtilsStep.java) | :+1:       | :+1:      | :white_large_square:       | :white_large_square:  |
 | [`groovy.GrEclipseFormatterStep`](lib-extra/src/main/java/com/diffplug/spotless/extra/groovy/GrEclipseFormatterStep.java) | :+1:       | :+1:      | :+1:      | :white_large_square:  |
 | [`java.GoogleJavaFormatStep`](lib/src/main/java/com/diffplug/spotless/java/GoogleJavaFormatStep.java) | :+1:       | :+1:      | :+1:      | :white_large_square:  |
 | [`java.ImportOrderStep`](lib/src/main/java/com/diffplug/spotless/java/ImportOrderStep.java) | :+1:       | :+1:      | :+1:      | :white_large_square:  |

lib/build.gradle

@@ -18,7 +18,8 @@ def NEEDS_GLUE = [
 	'scalafmt',
 	'jackson',
 	'gson',
-	'cleanthat'
+	'cleanthat',
+	'gherkin'
 ]
 for (glue in NEEDS_GLUE) {
 	sourceSets.register(glue) {
@@ -115,6 +116,9 @@ dependencies {
 
 	cleanthatCompileOnly 'io.github.solven-eu.cleanthat:java:2.6'
 	compatCleanthat2Dot1CompileAndTestOnly 'io.github.solven-eu.cleanthat:java:2.6'
+
+	gherkinCompileOnly 'io.cucumber:gherkin-utils:8.0.2'
+	gherkinCompileOnly 'org.slf4j:slf4j-api:2.0.0'
 }
 
 // we'll hold the core lib to a high standard

lib/src/gherkin/java/com/diffplug/spotless/glue/gherkin/GherkinUtilsFormatterFunc.java

@@ -0,0 +1,60 @@
+/*
+ * Copyright 2023 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.glue.gherkin;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.diffplug.spotless.FormatterFunc;
+import com.diffplug.spotless.gherkin.GherkinUtilsConfig;
+
+import io.cucumber.gherkin.GherkinParser;
+import io.cucumber.gherkin.utils.pretty.Pretty;
+import io.cucumber.gherkin.utils.pretty.Syntax;
+import io.cucumber.messages.types.Envelope;
+import io.cucumber.messages.types.GherkinDocument;
+import io.cucumber.messages.types.Source;
+import io.cucumber.messages.types.SourceMediaType;
+
+public class GherkinUtilsFormatterFunc implements FormatterFunc {
+	private static final Logger LOGGER = LoggerFactory.getLogger(GherkinUtilsFormatterFunc.class);
+
+	private final GherkinUtilsConfig gherkinSimpleConfig;
+
+	public GherkinUtilsFormatterFunc(GherkinUtilsConfig gherkinSimpleConfig) {
+		this.gherkinSimpleConfig = gherkinSimpleConfig;
+	}
+
+	// Follows https://github.com/cucumber/gherkin-utils/blob/main/java/src/test/java/io/cucumber/gherkin/utils/pretty/PrettyTest.java
+	private GherkinDocument parse(String gherkin) {
+		GherkinParser parser = GherkinParser
+				.builder()
+				.includeSource(false)
+				.build();
+		return parser.parse(Envelope.of(new Source("test.feature", gherkin, SourceMediaType.TEXT_X_CUCUMBER_GHERKIN_PLAIN)))
+				.findFirst()
+				.orElseThrow(() -> new IllegalArgumentException("No envelope"))
+				.getGherkinDocument()
+				.orElseThrow(() -> new IllegalArgumentException("No gherkin document"));
+	}
+
+	@Override
+	public String apply(String inputString) {
+		GherkinDocument gherkinDocument = parse(inputString);
+
+		return Pretty.prettyPrint(gherkinDocument, Syntax.gherkin);
+	}
+}

lib/src/main/java/com/diffplug/spotless/gherkin/GherkinUtilsConfig.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2023 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.gherkin;
+
+import java.io.Serializable;
+
+public class GherkinUtilsConfig implements Serializable {
+	private static final long serialVersionUID = 1L;
+
+	public static int defaultIndentSpaces() {
+		// https://cucumber.io/docs/gherkin/reference/
+		// Recommended indentation is 2 spaces
+		return 2;
+	}
+
+	final int indentSpaces;
+
+	public GherkinUtilsConfig(int indentSpaces) {
+		this.indentSpaces = indentSpaces;
+	}
+
+	public int getIndentSpaces() {
+		return indentSpaces;
+	}
+}

lib/src/main/java/com/diffplug/spotless/gherkin/GherkinUtilsStep.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright 2021-2023 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.gherkin;
+
+import java.io.IOException;
+import java.io.Serializable;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.InvocationTargetException;
+import java.util.Objects;
+
+import com.diffplug.spotless.FormatterFunc;
+import com.diffplug.spotless.FormatterStep;
+import com.diffplug.spotless.JarState;
+import com.diffplug.spotless.Provisioner;
+
+public class GherkinUtilsStep {
+	private static final String MAVEN_COORDINATE = "io.cucumber:gherkin-utils:";
+	private static final String DEFAULT_VERSION = "8.0.2";
+
+	public static String defaultVersion() {
+		return DEFAULT_VERSION;
+	}
+
+	public static FormatterStep create(GherkinUtilsConfig gherkinSimpleConfig,
+			String formatterVersion, Provisioner provisioner) {
+		Objects.requireNonNull(provisioner, "provisioner cannot be null");
+		return FormatterStep.createLazy("gherkin", () -> new GherkinUtilsStep.State(gherkinSimpleConfig, formatterVersion, provisioner), GherkinUtilsStep.State::toFormatter);
+	}
+
+	private static final class State implements Serializable {
+		private static final long serialVersionUID = 1L;
+
+		private final GherkinUtilsConfig gherkinSimpleConfig;
+		private final JarState jarState;
+
+		private State(GherkinUtilsConfig gherkinSimpleConfig, String formatterVersion, Provisioner provisioner) throws IOException {
+			this.gherkinSimpleConfig = gherkinSimpleConfig;
+			this.jarState = JarState.from(MAVEN_COORDINATE + formatterVersion, provisioner);
+		}
+
+		FormatterFunc toFormatter() throws ClassNotFoundException, NoSuchMethodException, InvocationTargetException,
+				InstantiationException, IllegalAccessException {
+			Class<?> formatterFunc = jarState.getClassLoader().loadClass("com.diffplug.spotless.glue.gherkin.GherkinUtilsFormatterFunc");
+			Constructor<?> constructor = formatterFunc.getConstructor(GherkinUtilsConfig.class);
+			return (FormatterFunc) constructor.newInstance(gherkinSimpleConfig);
+		}
+	}
+
+	private GherkinUtilsStep() {
+		// cannot be directly instantiated
+	}
+}

plugin-gradle/CHANGES.md

@@ -15,6 +15,7 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
   Mirrors are selected by prefix match, for example `https://download.eclipse.org/eclipse/updates/4.26/` will be redirected to `https://some.internal.mirror/eclipse/eclipse/updates/4.26/`.
   The same configuration exists for `greclipse` and `eclipseCdt`.
 * The `style` option in Palantir Java Format ([#1654](https://github.com/diffplug/spotless/pull/1654)).
+* Added support for Gherkin feature files ([#1649](https://github.com/diffplug/spotless/issues/1649)).
 ### Changes
 * **POTENTIALLY BREAKING** Drop support for `googleJavaFormat` versions < `1.8`. ([#1630](https://github.com/diffplug/spotless/pull/1630))
 * Bump default `googleJavaFormat` version `1.15.0` -> `1.16.0`. ([#1630](https://github.com/diffplug/spotless/pull/1630))

plugin-gradle/README.md

@@ -66,6 +66,8 @@ Spotless supports all of Gradle's built-in performance features (incremental bui
   - [Typescript](#typescript) ([tsfmt](#tsfmt), [prettier](#prettier), [ESLint](#eslint-typescript))
   - [Javascript](#javascript) ([prettier](#prettier), [ESLint](#eslint-javascript))
   - [JSON](#json)
+  - [YAML](#yaml)
+  - [Gherkin](#gherkin)
   - Multiple languages
     - [Prettier](#prettier) ([plugins](#prettier-plugins), [npm detection](#npm-detection), [`.npmrc` detection](#npmrc-detection), [caching `npm install` results](#caching-results-of-npm-install))
       - javascript, jsx, angular, vue, flow, typescript, css, less, scss, html, json, graphql, markdown, ymaml
@@ -850,7 +852,34 @@ spotless {
 }
 ```
 
-<a name="applying-prettier-to-javascript--flow--typescript--css--scss--less--jsx--graphql--yaml--etc"></a>
+## Gherkin
+
+- `com.diffplug.gradle.spotless.GherkinExtension` [javadoc](https://javadoc.io/doc/com.diffplug.spotless/spotless-plugin-gradle/6.17.0/com/diffplug/gradle/spotless/GherkinExtension.html), [code](https://github.com/diffplug/spotless/blob/main/plugin-gradle/src/main/java/com/diffplug/gradle/spotless/GherkinExtension.java)
+
+```gradle
+spotless {
+  gherkin {
+    target 'src/**/*.feature' // you have to set the target manually
+    gherkinUtils() // has its own section below
+  }
+}
+```
+
+### gherkinUtils
+
+[homepage](https://github.com/cucumber/gherkin-utils). [changelog](https://github.com/cucumber/gherkin-utils/blob/main/CHANGELOG.md).
+
+Uses a Gherkin pretty-printer that optionally allows configuring the number of spaces that are used to pretty print objects:
+
+```gradle
+spotless {
+  gherkin {
+    target 'src/**/*.feature'     // required to be set explicitly
+    gherkinUtils()
+      .version('8.0.2')           // optional: custom version of 'io.cucumber:gherkin-utils'
+  }
+}
+```
 
 ## Prettier
 

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

@@ -0,0 +1,63 @@
+/*
+ * Copyright 2016-2023 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.FormatterStep;
+import com.diffplug.spotless.gherkin.GherkinUtilsStep;
+
+public class GherkinExtension extends FormatExtension {
+	static final String NAME = "gherkin";
+
+	@Inject
+	public GherkinExtension(SpotlessExtension spotless) {
+		super(spotless);
+	}
+
+	@Override
+	protected void setupTask(SpotlessTask task) {
+		if (target == null) {
+			throw noDefaultTargetException();
+		}
+		super.setupTask(task);
+	}
+
+	public GherkinUtilsConfig gherkinUtils() {
+		return new GherkinUtilsConfig();
+	}
+
+	public class GherkinUtilsConfig {
+		private String version;
+		private int indent;
+
+		public GherkinUtilsConfig() {
+			this.version = GherkinUtilsStep.defaultVersion();
+			this.indent = com.diffplug.spotless.gherkin.GherkinUtilsConfig.defaultIndentSpaces();
+			addStep(createStep());
+		}
+
+		public void version(String version) {
+			this.version = version;
+			replaceStep(createStep());
+		}
+
+		private FormatterStep createStep() {
+			return GherkinUtilsStep.create(new com.diffplug.spotless.gherkin.GherkinUtilsConfig(indent), version, provisioner());
+		}
+	}
+
+}

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

@@ -199,6 +199,12 @@ public void yaml(Action<YamlExtension> closure) {
 		format(YamlExtension.NAME, YamlExtension.class, closure);
 	}
 
+	/** Configures the special Gherkin-specific extension. */
+	public void gherkin(Action<GherkinExtension> closure) {
+		requireNonNull(closure);
+		format(GherkinExtension.NAME, GherkinExtension.class, closure);
+	}
+
 	/** Configures a custom extension. */
 	public void format(String name, Action<FormatExtension> closure) {
 		requireNonNull(name, "name");

plugin-gradle/src/test/java/com/diffplug/gradle/spotless/GherkinExtensionTest.java

@@ -0,0 +1,44 @@
+/*
+ * Copyright 2021-2023 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 java.io.IOException;
+
+import org.junit.jupiter.api.Test;
+
+public class GherkinExtensionTest extends GradleIntegrationHarness {
+	@Test
+	public void defaultFormatting() throws IOException {
+		setFile("build.gradle").toLines(
+				"plugins {",
+				"    id 'java'",
+				"    id 'com.diffplug.spotless'",
+				"}",
+				"repositories { mavenCentral() }",
+				"spotless {",
+				"  gherkin {",
+				"    target 'examples/**/*.feature'",
+				"    gherkinUtils()",
+				"  }",
+				"}");
+		setFile("src/main/resources/example.feature").toResource("gherkin/minimalBefore.feature");
+		setFile("examples/main/resources/example.feature").toResource("gherkin/minimalBefore.feature");
+		gradleRunner().withArguments("spotlessApply").build();
+		assertFile("src/main/resources/example.feature").sameAsResource("gherkin/minimalBefore.feature");
+		assertFile("examples/main/resources/example.feature").sameAsResource("gherkin/minimalAfter.feature");
+	}
+
+}