Support diktat - Kotlin code style analyzer

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
+* Support for diktat ([#789](https://github.com/diffplug/spotless/pull/789))
 
 ## [2.11.0] - 2021-01-04
 ### Added

README.md

@@ -60,6 +60,7 @@ lib('java.RemoveUnusedImportsStep')              +'{{yes}}       | {{yes}}
 extra('java.EclipseJdtFormatterStep')            +'{{yes}}       | {{yes}}      | {{yes}}      | {{no}}  |',
 lib('kotlin.KtLintStep')                         +'{{yes}}       | {{yes}}      | {{yes}}      | {{no}}  |',
 lib('kotlin.KtfmtStep')                          +'{{yes}}       | {{yes}}      | {{no}}       | {{no}}  |',
+lib('kotlin.DiktatStep')                         +'{{yes}}       | {{yes}}      | {{no}}       | {{no}}  |',
 lib('markdown.FreshMarkStep')                    +'{{yes}}       | {{no}}       | {{no}}       | {{no}}  |',
 lib('npm.PrettierFormatterStep')                 +'{{yes}}       | {{yes}}      | {{no}}       | {{no}}  |',
 lib('npm.TsFmtFormatterStep')                    +'{{yes}}       | {{yes}}      | {{no}}       | {{no}}  |',
@@ -95,6 +96,7 @@ extra('wtp.EclipseWtpFormatterStep')             +'{{yes}}       | {{yes}}
 | [`java.EclipseJdtFormatterStep`](lib-extra/src/main/java/com/diffplug/spotless/extra/java/EclipseJdtFormatterStep.java) | :+1:       | :+1:      | :+1:      | :white_large_square:  |
 | [`kotlin.KtLintStep`](lib/src/main/java/com/diffplug/spotless/kotlin/KtLintStep.java) | :+1:       | :+1:      | :+1:      | :white_large_square:  |
 | [`kotlin.KtfmtStep`](lib/src/main/java/com/diffplug/spotless/kotlin/KtfmtStep.java) | :+1:       | :+1:      | :white_large_square:       | :white_large_square:  |
+| [`kotlin.DiktatStep`](lib/src/main/java/com/diffplug/spotless/kotlin/DiktatStep.java) | :+1:       | :+1:      | :white_large_square:       | :white_large_square:  |
 | [`markdown.FreshMarkStep`](lib/src/main/java/com/diffplug/spotless/markdown/FreshMarkStep.java) | :+1:       | :white_large_square:       | :white_large_square:       | :white_large_square:  |
 | [`npm.PrettierFormatterStep`](lib/src/main/java/com/diffplug/spotless/npm/PrettierFormatterStep.java) | :+1:       | :+1:      | :white_large_square:       | :white_large_square:  |
 | [`npm.TsFmtFormatterStep`](lib/src/main/java/com/diffplug/spotless/npm/TsFmtFormatterStep.java) | :+1:       | :+1:      | :white_large_square:       | :white_large_square:  |

lib/src/main/java/com/diffplug/spotless/kotlin/DiktatStep.java

@@ -0,0 +1,186 @@
+/*
+ * Copyright 2021 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.kotlin;
+
+import java.io.IOException;
+import java.io.Serializable;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.lang.reflect.Proxy;
+import java.util.*;
+
+import com.diffplug.spotless.*;
+
+/** Wraps up [diktat](https://github.com/cqfn/diKTat) as a FormatterStep. */
+public class DiktatStep {
+
+	// prevent direct instantiation
+	private DiktatStep() {}
+
+	private static final String DEFAULT_VERSION = "0.4.0";
+	static final String NAME = "diktat";
+	static final String PACKAGE_DIKTAT = "org.cqfn.diktat";
+	static final String PACKAGE_KTLINT = "com.pinterest.ktlint";
+	static final String MAVEN_COORDINATE = PACKAGE_DIKTAT + ":diktat-rules:";
+
+	public static String defaultVersionDiktat() {
+		return DEFAULT_VERSION;
+	}
+
+	public static FormatterStep create(Provisioner provisioner) {
+		return create(defaultVersionDiktat(), provisioner);
+	}
+
+	public static FormatterStep create(String versionDiktat, Provisioner provisioner) {
+		return create(versionDiktat, provisioner, Collections.emptyMap(), null);
+	}
+
+	public static FormatterStep create(String versionDiktat, Provisioner provisioner, FileSignature config) {
+		return create(versionDiktat, provisioner, Collections.emptyMap(), config);
+	}
+
+	public static FormatterStep create(String versionDiktat, Provisioner provisioner, Map<String, String> userData, FileSignature config) {
+		return create(versionDiktat, provisioner, false, userData, config);
+	}
+
+	public static FormatterStep createForScript(String versionDiktat, Provisioner provisioner, FileSignature config) {
+		return createForScript(versionDiktat, provisioner, Collections.emptyMap(), config);
+	}
+
+	public static FormatterStep createForScript(String versionDiktat, Provisioner provisioner, Map<String, String> userData, FileSignature config) {
+		return create(versionDiktat, provisioner, true, userData, config);
+	}
+
+	public static FormatterStep create(String versionDiktat, Provisioner provisioner, boolean isScript, Map<String, String> userData, FileSignature config) {
+		Objects.requireNonNull(versionDiktat, "versionDiktat");
+		Objects.requireNonNull(provisioner, "provisioner");
+		return FormatterStep.createLazy(NAME,
+				() -> new DiktatStep.State(versionDiktat, provisioner, isScript, userData, config),
+				DiktatStep.State::createFormat);
+	}
+
+	static final class State implements Serializable {
+
+		private static final long serialVersionUID = 1L;
+
+		/** Are the files being linted Kotlin script files. */
+		private final boolean isScript;
+		private final FileSignature config;
+		private final String pkg;
+		private final String pkgKtlint;
+		final JarState jar;
+		private final TreeMap<String, String> userData;
+
+		State(String versionDiktat, Provisioner provisioner, boolean isScript, Map<String, String> userData, FileSignature config) throws IOException {
+
+			HashSet<String> pkgSet = new HashSet<>();
+			pkgSet.add(MAVEN_COORDINATE + versionDiktat);
+
+			this.userData = new TreeMap<>(userData);
+			this.pkg = PACKAGE_DIKTAT;
+			this.pkgKtlint = PACKAGE_KTLINT;
+			this.jar = JarState.from(pkgSet, provisioner);
+			this.isScript = isScript;
+			this.config = config;
+		}
+
+		FormatterFunc createFormat() throws Exception {
+
+			ClassLoader classLoader = jar.getClassLoader();
+
+			// first, we get the diktat rules
+			if (config != null) {
+				System.setProperty("diktat.config.path", config.getOnlyFile().getAbsolutePath());
+			}
+
+			Class<?> ruleSetProviderClass = classLoader.loadClass(pkg + ".ruleset.rules.DiktatRuleSetProvider");
+			Object diktatRuleSet = ruleSetProviderClass.getMethod("get").invoke(ruleSetProviderClass.newInstance());
+			Iterable<?> ruleSets = Collections.singletonList(diktatRuleSet);
+
+			// next, we create an error callback which throws an assertion error when the format is bad
+			Class<?> function2Interface = classLoader.loadClass("kotlin.jvm.functions.Function2");
+			Class<?> lintErrorClass = classLoader.loadClass(pkgKtlint + ".core.LintError");
+			Method detailGetter = lintErrorClass.getMethod("getDetail");
+			Method lineGetter = lintErrorClass.getMethod("getLine");
+			Method colGetter = lintErrorClass.getMethod("getCol");
+
+			// grab the KtLint singleton
+			Class<?> ktlintClass = classLoader.loadClass(pkgKtlint + ".core.KtLint");
+			Object ktlint = ktlintClass.getDeclaredField("INSTANCE").get(null);
+
+			Class<?> paramsClass = classLoader.loadClass(pkgKtlint + ".core.KtLint$Params");
+			// and its constructor
+			Constructor<?> constructor = paramsClass.getConstructor(
+					/* fileName, nullable */ String.class,
+					/* text */ String.class,
+					/* ruleSets */ Iterable.class,
+					/* userData */ Map.class,
+					/* callback */ function2Interface,
+					/* script */ boolean.class,
+					/* editorConfigPath, nullable */ String.class,
+					/* debug */ boolean.class);
+			Method formatterMethod = ktlintClass.getMethod("format", paramsClass);
+			FormatterFunc.NeedsFile formatterFunc = (input, file) -> {
+				ArrayList<Object> errors = new ArrayList<>();
+
+				Object formatterCallback = Proxy.newProxyInstance(classLoader, new Class[]{function2Interface},
+						(proxy, method, args) -> {
+							Object lintError = args[0]; //ktlint.core.LintError
+							boolean corrected = (Boolean) args[1];
+							if (!corrected) {
+								errors.add(lintError);
+							}
+							return null;
+						});
+
+				userData.put("file_path", file.getAbsolutePath());
+				try {
+					Object params = constructor.newInstance(
+							/* fileName, nullable */ file.getName(),
+							/* text */ input,
+							/* ruleSets */ ruleSets,
+							/* userData */ userData,
+							/* callback */ formatterCallback,
+							/* script */ isScript,
+							/* editorConfigPath, nullable */ null,
+							/* debug */ false);
+					String result = (String) formatterMethod.invoke(ktlint, params);
+					if (!errors.isEmpty()) {
+						StringBuilder error = new StringBuilder("");
+						error.append("There are ").append(errors.size()).append(" unfixed errors:");
+						for (Object er : errors) {
+							String detail = (String) detailGetter.invoke(er);
+							int line = (Integer) lineGetter.invoke(er);
+							int col = (Integer) colGetter.invoke(er);
+
+							error.append(System.lineSeparator()).append("Error on line: ").append(line).append(", column: ").append(col).append(" cannot be fixed automatically")
+									.append(System.lineSeparator()).append(detail);
+						}
+						throw new AssertionError(error);
+					}
+					return result;
+				} catch (InvocationTargetException e) {
+					throw ThrowingEx.unwrapCause(e);
+				}
+			};
+
+			return formatterFunc;
+		}
+
+	}
+
+}

plugin-gradle/CHANGES.md

@@ -3,6 +3,8 @@
 We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (starting after version `3.27.0`).
 
 ## [Unreleased]
+### Added
+* Support for diktat in KotlinGradleExtension ([#789](https://github.com/diffplug/spotless/pull/789))
 
 ## [5.9.0] - 2021-01-04
 ### Added

plugin-gradle/README.md

@@ -60,7 +60,7 @@ Spotless supports all of Gradle's built-in performance features (incremental bui
 - **Languages**
   - [Java](#java) ([google-java-format](#google-java-format), [eclipse jdt](#eclipse-jdt), [clang-format](#clang-format), [prettier](#prettier))
   - [Groovy](#groovy) ([eclipse groovy](#eclipse-groovy))
-  - [Kotlin](#kotlin) ([ktlint](#ktlint), [ktfmt](#ktfmt), [prettier](#prettier))
+  - [Kotlin](#kotlin) ([ktlint](#ktlint), [ktfmt](#ktfmt), [prettier](#prettier), [diktat](#diktat))
   - [Scala](#scala) ([scalafmt](#scalafmt))
   - [C/C++](#cc) ([clang-format](#clang-format), [eclipse cdt](#eclipse-cdt))
   - [Python](#python) ([black](#black))
@@ -253,6 +253,7 @@ spotless { // if you are using build.gradle.kts, instead of 'spotless {' use:
     // by default the target is every '.kt' and '.kts` file in the java sourcesets
     ktlint()   // has its own section below
     ktfmt()    // has its own section below
+    diktat()   // has its own section below
     prettier() // has its own section below
     licenseHeader '/* (C)$YEAR */' // or licenseHeaderFile
   }
@@ -288,6 +289,19 @@ spotless {
     ktfmt('0.15').dropboxStyle() // version and dropbox style are optional
 ```
 
+<a name="applying-diktat-to-kotlin-files"></a>
+
+### diktat
+
+[homepage](https://github.com/cqfn/diKTat). [changelog](https://github.com/cqfn/diKTat/releases).  You can provide configuration path manually as `configPath`.
+
+```kotlin
+spotless {
+  kotlin {
+    // version and configPath are both optional
+    diktat('0.4.0').configPath("full/path/to/diktat-analysis.yml")
+```
+
 <a name="applying-scalafmt-to-scala-files"></a>
 
 ## Scala

plugin-gradle/build.gradle

@@ -69,6 +69,7 @@ if (version.endsWith('-SNAPSHOT')) {
 			'eclipse',
 			'ktlint',
 			'ktfmt',
+			'diktat',
 			'tsfmt',
 			'prettier',
 			'scalafmt',

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

@@ -15,8 +15,11 @@
  */
 package com.diffplug.gradle.spotless;
 
+import static com.diffplug.spotless.FileSignature.signAsList;
 import static com.diffplug.spotless.kotlin.KotlinConstants.LICENSE_HEADER_DELIMITER;
 
+import java.io.File;
+import java.io.IOException;
 import java.util.Collections;
 import java.util.Map;
 import java.util.Objects;
@@ -28,7 +31,9 @@
 import org.gradle.api.plugins.JavaPluginConvention;
 import org.gradle.api.tasks.SourceSet;
 
+import com.diffplug.spotless.FileSignature;
 import com.diffplug.spotless.FormatterStep;
+import com.diffplug.spotless.kotlin.DiktatStep;
 import com.diffplug.spotless.kotlin.KtLintStep;
 import com.diffplug.spotless.kotlin.KtfmtStep;
 import com.diffplug.spotless.kotlin.KtfmtStep.Style;
@@ -122,6 +127,38 @@ private FormatterStep createStep() {
 		}
 	}
 
+	/** Adds the specified version of [diktat](https://github.com/cqfn/diKTat). */
+	public DiktatFormatExtension diktat(String version) {
+		Objects.requireNonNull(version);
+		return new DiktatFormatExtension(version, null);
+	}
+
+	public DiktatFormatExtension diktat() {
+		return diktat(DiktatStep.defaultVersionDiktat());
+	}
+
+	public class DiktatFormatExtension {
+
+		private final String version;
+		private FileSignature config;
+
+		DiktatFormatExtension(String version, FileSignature config) {
+			this.version = version;
+			this.config = config;
+			addStep(createStep());
+		}
+
+		public void withConfig(String path) throws IOException {
+			// Specify the path to the configuration file
+			this.config = signAsList(new File(path));
+			replaceStep(createStep());
+		}
+
+		private FormatterStep createStep() {
+			return DiktatStep.create(version, provisioner(), config);
+		}
+	}
+
 	/** If the user hasn't specified the files yet, we'll assume he/she means all of the kotlin files. */
 	@Override
 	protected void setupTask(SpotlessTask task) {

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2020 DiffPlug
+ * Copyright 2016-2021 DiffPlug
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,14 +15,20 @@
  */
 package com.diffplug.gradle.spotless;
 
+import static com.diffplug.spotless.FileSignature.signAsList;
+
+import java.io.File;
+import java.io.IOException;
 import java.util.Collections;
 import java.util.Map;
 import java.util.Objects;
 
 import javax.inject.Inject;
 
 import com.diffplug.common.collect.ImmutableSortedMap;
+import com.diffplug.spotless.FileSignature;
 import com.diffplug.spotless.FormatterStep;
+import com.diffplug.spotless.kotlin.DiktatStep;
 import com.diffplug.spotless.kotlin.KtLintStep;
 import com.diffplug.spotless.kotlin.KtfmtStep;
 import com.diffplug.spotless.kotlin.KtfmtStep.Style;
@@ -104,6 +110,38 @@ private FormatterStep createStep() {
 		}
 	}
 
+	/** Adds the specified version of [diktat](https://github.com/cqfn/diKTat). */
+	public DiktatFormatExtension diktat(String version) {
+		Objects.requireNonNull(version, "version");
+		return new DiktatFormatExtension(version, null);
+	}
+
+	public DiktatFormatExtension diktat() {
+		return diktat(DiktatStep.defaultVersionDiktat());
+	}
+
+	public class DiktatFormatExtension {
+
+		private final String version;
+		private FileSignature config;
+
+		DiktatFormatExtension(String version, FileSignature config) {
+			this.version = version;
+			this.config = config;
+			addStep(createStep());
+		}
+
+		public void withConfig(String path) throws IOException {
+			// Specify the path to the configuration file
+			this.config = signAsList(new File(path));
+			replaceStep(createStep());
+		}
+
+		private FormatterStep createStep() {
+			return DiktatStep.createForScript(version, provisioner(), config);
+		}
+	}
+
 	@Override
 	protected void setupTask(SpotlessTask task) {
 		if (target == null) {