Implemented max lines width changing support for Kotlin ktfmt formatt…

…er for Gradle plugin.
diffplug · Mar 11, 2022 · b679ec9 · b679ec9
1 parent 32210d0
commit b679ec9
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Showing 7 changed files with 172 additions and 31 deletions.
diff --git a/lib/src/main/java/com/diffplug/spotless/kotlin/KtfmtStep.java b/lib/src/main/java/com/diffplug/spotless/kotlin/KtfmtStep.java
@@ -21,9 +21,11 @@
 import java.io.Serializable;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
+import java.util.Arrays;
 import java.util.Objects;
 
 import com.diffplug.spotless.*;
+import javax.annotation.Nullable;
 
 /**
  * Wraps up <a href="https://github.com/facebookincubator/ktfmt">ktfmt</a> as a FormatterStep.
@@ -64,6 +66,14 @@ String getSince() {
 
 	private static final String DROPBOX_STYLE_METHOD = "dropboxStyle";
 
+	private static final String FORMATTING_OPTIONS_METHOD_COPY = "copy";
+	private static final String FORMATTING_OPTIONS_METHOD_GET_STYLE = "getStyle";
+	private static final String FORMATTING_OPTIONS_METHOD_GET_MAX_WIDTH = "getMaxWidth";
+	private static final String FORMATTING_OPTIONS_METHOD_GET_BLOCK_INDENT = "getBlockIndent";
+	private static final String FORMATTING_OPTIONS_METHOD_GET_CONTINUATION_INDENT = "getContinuationIndent";
+	private static final String FORMATTING_OPTIONS_METHOD_GET_REMOVE_UNUSED_IMPORTS = "getRemoveUnusedImports";
+	private static final String FORMATTING_OPTIONS_METHOD_GET_DEBUGGING_PRINT_OPS_AFTER_FORMATTING = "getDebuggingPrintOpsAfterFormatting";
+
 	/**
 	 * The <code>format</code> method is available in the link below.
 	 *
@@ -78,16 +88,16 @@ public static FormatterStep create(Provisioner provisioner) {
 
 	/** Creates a step which formats everything - code, import order, and unused imports. */
 	public static FormatterStep create(String version, Provisioner provisioner) {
-		return create(version, provisioner, DEFAULT);
+		return create(version, provisioner, null, DEFAULT);
 	}
 
 	/** Creates a step which formats everything - code, import order, and unused imports. */
-	public static FormatterStep create(String version, Provisioner provisioner, Style style) {
+	public static FormatterStep create(String version, Provisioner provisioner, @Nullable Integer maxWidth, Style style) {
 		Objects.requireNonNull(version, "version");
 		Objects.requireNonNull(provisioner, "provisioner");
 		Objects.requireNonNull(style, "style");
 		return FormatterStep.createLazy(
-				NAME, () -> new State(version, provisioner, style), State::createFormat);
+				NAME, () -> new State(version, provisioner, maxWidth, style), State::createFormat);
 	}
 
 	public static String defaultVersion() {
@@ -104,16 +114,22 @@ static final class State implements Serializable {
 		private final String version;
 
 		private final String pkg;
+		/**
+		 * Option that allows change line width before breaking
+		 */
+		@Nullable
+		private final Integer maxWidth;
 		/**
 		 * Option that allows to apply formatting options to perform a 4 spaces block and continuation indent.
 		 */
 		private final Style style;
 		/** The jar that contains the formatter. */
 		final JarState jarState;
 
-		State(String version, Provisioner provisioner, Style style) throws IOException {
+		State(String version, Provisioner provisioner, @Nullable Integer maxWidth, Style style) throws IOException {
 			this.version = version;
 			this.pkg = PACKAGE;
+			this.maxWidth = maxWidth;
 			this.style = style;
 			this.jarState = JarState.from(MAVEN_COORDINATE + version, provisioner);
 		}
@@ -122,29 +138,55 @@ FormatterFunc createFormat() throws Exception {
 			ClassLoader classLoader = jarState.getClassLoader();
 			return input -> {
 				try {
-					if (style == DEFAULT) {
-						Method formatterMethod = getFormatterClazz(classLoader).getMethod(FORMATTER_METHOD, String.class);
-						return (String) formatterMethod.invoke(getFormatterClazz(classLoader), input);
-					} else {
-						Method formatterMethod = getFormatterClazz(classLoader).getMethod(FORMATTER_METHOD, getFormattingOptionsClazz(classLoader),
-								String.class);
-						Object formattingOptions = getCustomFormattingOptions(classLoader, style);
-						return (String) formatterMethod.invoke(getFormatterClazz(classLoader), formattingOptions, input);
-					}
+					Method formatterMethod = getFormatterClazz(classLoader).getMethod(FORMATTER_METHOD, getFormattingOptionsClazz(classLoader),
+							String.class);
+					Object formattingOptions = getCustomFormattingOptions(classLoader, maxWidth, style);
+					return (String) formatterMethod.invoke(getFormatterClazz(classLoader), formattingOptions, input);
 				} catch (InvocationTargetException e) {
 					throw ThrowingEx.unwrapCause(e);
 				}
 			};
 		}
 
-		private Object getCustomFormattingOptions(ClassLoader classLoader, Style style) throws Exception {
+		private Object getCustomFormattingOptions(ClassLoader classLoader, @Nullable Integer maxWidth, Style style) throws Exception {
 			if (BadSemver.version(version) < BadSemver.version(style.since)) {
 				throw new IllegalStateException(String.format("The style %s is available from version %s (current version: %s)", style.name(), style.since, version));
 			}
 
 			try {
 				// ktfmt v0.19 and later
-				return getFormatterClazz(classLoader).getField(style.getFormat()).get(null);
+				Object formattingOptionVariable;
+				if (style == DEFAULT) {
+					formattingOptionVariable = getFormattingOptionsClazz(classLoader).getDeclaredConstructor().newInstance();
+				} else {
+					formattingOptionVariable = getFormatterClazz(classLoader).getField(style.getFormat()).get(null);
+				}
+
+				if (maxWidth != null) {
+					if (BadSemver.version(version) < BadSemver.version(0, 31)) {
+						throw new IllegalStateException("Max width configuration supported only for ktfmt 0.31 and later");
+					}
+
+					Class<?> formattingOptionsClass = getFormattingOptionsClazz(classLoader);
+					Object styleValue = formattingOptionsClass.getMethod(FORMATTING_OPTIONS_METHOD_GET_STYLE).invoke(formattingOptionVariable);
+					Object maxWidthValue = formattingOptionsClass.getMethod(FORMATTING_OPTIONS_METHOD_GET_MAX_WIDTH).invoke(formattingOptionVariable);
+					Object blockIndentValue = formattingOptionsClass.getMethod(FORMATTING_OPTIONS_METHOD_GET_BLOCK_INDENT).invoke(formattingOptionVariable);
+					Object continuationIndentValue = formattingOptionsClass.getMethod(FORMATTING_OPTIONS_METHOD_GET_CONTINUATION_INDENT).invoke(formattingOptionVariable);
+					Object removeUnusedImportsValue = formattingOptionsClass.getMethod(FORMATTING_OPTIONS_METHOD_GET_REMOVE_UNUSED_IMPORTS).invoke(formattingOptionVariable);
+					Object debuggingPrintOpsAfterFormattingValue = formattingOptionsClass.getMethod(FORMATTING_OPTIONS_METHOD_GET_DEBUGGING_PRINT_OPS_AFTER_FORMATTING).invoke(formattingOptionVariable);
+
+					Method copyFormattingOption = Arrays.stream(formattingOptionsClass.getDeclaredMethods())
+							.filter(method -> FORMATTING_OPTIONS_METHOD_COPY.equals(method.getName())).findFirst().get();
+					formattingOptionVariable = copyFormattingOption.invoke(formattingOptionVariable,
+							styleValue,
+							maxWidth > 0 ? maxWidth : maxWidthValue,
+							blockIndentValue,
+							continuationIndentValue,
+							removeUnusedImportsValue,
+							debuggingPrintOpsAfterFormattingValue);
+				}
+
+				return formattingOptionVariable;
 			} catch (NoSuchFieldException ignored) {}
 
 			// fallback to old, pre-0.19 ktfmt interface.

diff --git a/plugin-gradle/src/main/java/com/diffplug/gradle/spotless/KotlinExtension.java b/plugin-gradle/src/main/java/com/diffplug/gradle/spotless/KotlinExtension.java
@@ -103,6 +103,7 @@ public KtfmtConfig ktfmt(String version) {
 
 	public class KtfmtConfig {
 		final String version;
+		Integer maxWidth;
 		Style style;
 
 		KtfmtConfig(String version) {
@@ -111,25 +112,35 @@ public class KtfmtConfig {
 			addStep(createStep());
 		}
 
-		public void dropboxStyle() {
-			style(Style.DROPBOX);
+		public KtfmtConfig maxWidth(int maxWidth) {
+			if (maxWidth <= 0) {
+				throw new IllegalArgumentException("Passed maxWidth parameter must be positive value");
+			}
+			this.maxWidth = maxWidth;
+			replaceStep(createStep());
+			return this;
 		}
 
-		public void googleStyle() {
-			style(Style.GOOGLE);
+		public KtfmtConfig dropboxStyle() {
+			return style(Style.DROPBOX);
 		}
 
-		public void kotlinlangStyle() {
-			style(Style.KOTLINLANG);
+		public KtfmtConfig googleStyle() {
+			return style(Style.GOOGLE);
 		}
 
-		public void style(Style style) {
+		public KtfmtConfig kotlinlangStyle() {
+			return style(Style.KOTLINLANG);
+		}
+
+		public KtfmtConfig style(Style style) {
 			this.style = style;
 			replaceStep(createStep());
+			return this;
 		}
 
 		private FormatterStep createStep() {
-			return KtfmtStep.create(version, provisioner(), style);
+			return KtfmtStep.create(version, provisioner(), maxWidth, style);
 		}
 	}
 

diff --git a/plugin-gradle/src/main/java/com/diffplug/gradle/spotless/KotlinGradleExtension.java b/plugin-gradle/src/main/java/com/diffplug/gradle/spotless/KotlinGradleExtension.java
@@ -89,33 +89,45 @@ public KtfmtConfig ktfmt(String version) {
 
 	public class KtfmtConfig {
 		final String version;
+		Integer maxWidth;
 		Style style;
 
 		KtfmtConfig(String version) {
 			this.version = Objects.requireNonNull(version);
+			this.maxWidth = null;
 			this.style = Style.DEFAULT;
 			addStep(createStep());
 		}
 
-		public void style(Style style) {
+		public KtfmtConfig maxWidth(int maxWidth) {
+			if (maxWidth <= 0) {
+				throw new IllegalArgumentException("Passed maxWidth parameter must be positive value");
+			}
+			this.maxWidth = maxWidth;
+			replaceStep(createStep());
+			return this;
+		}
+
+		public KtfmtConfig style(Style style) {
 			this.style = style;
 			replaceStep(createStep());
+			return this;
 		}
 
-		public void dropboxStyle() {
-			style(Style.DROPBOX);
+		public KtfmtConfig dropboxStyle() {
+			return style(Style.DROPBOX);
 		}
 
-		public void googleStyle() {
-			style(Style.GOOGLE);
+		public KtfmtConfig googleStyle() {
+			return style(Style.GOOGLE);
 		}
 
-		public void kotlinlangStyle() {
-			style(Style.KOTLINLANG);
+		public KtfmtConfig kotlinlangStyle() {
+			return style(Style.KOTLINLANG);
 		}
 
 		private FormatterStep createStep() {
-			return KtfmtStep.create(version, provisioner(), style);
+			return KtfmtStep.create(version, provisioner(), maxWidth, style);
 		}
 	}
 

diff --git a/plugin-gradle/src/test/java/com/diffplug/gradle/spotless/KotlinExtensionTest.java b/plugin-gradle/src/test/java/com/diffplug/gradle/spotless/KotlinExtensionTest.java
@@ -269,4 +269,44 @@ void testWithNonStandardYearSeparatorKtfmt() throws IOException {
 			matcher.startsWith("// License Header 2012, 2014");
 		});
 	}
+
+	@Test
+	@EnabledForJreRange(min = JAVA_11) // ktfmt's dependency, google-java-format 1.8 requires a minimum of JRE 11+.
+	void testWithCustomMaxWidthDefaultStyleKtfmt() throws IOException {
+		setFile("build.gradle").toLines(
+				"plugins {",
+				"    id 'org.jetbrains.kotlin.jvm' version '1.5.31'",
+				"    id 'com.diffplug.spotless'",
+				"}",
+				"repositories { mavenCentral() }",
+				"spotless {",
+				"    kotlin {",
+				"        ktfmt().maxWidth(120)",
+				"    }",
+				"}");
+
+		setFile("src/main/kotlin/max-width.kt").toResource("kotlin/ktfmt/max-width.dirty");
+		gradleRunner().withArguments("spotlessApply").build();
+		assertFile("src/main/kotlin/max-width.kt").sameAsResource("kotlin/ktfmt/max-width.clean");
+	}
+
+	@Test
+	@EnabledForJreRange(min = JAVA_11) // ktfmt's dependency, google-java-format 1.8 requires a minimum of JRE 11+.
+	void testWithCustomMaxWidthDropboxStyleKtfmt() throws IOException {
+		setFile("build.gradle").toLines(
+				"plugins {",
+				"    id 'org.jetbrains.kotlin.jvm' version '1.5.31'",
+				"    id 'com.diffplug.spotless'",
+				"}",
+				"repositories { mavenCentral() }",
+				"spotless {",
+				"    kotlin {",
+				"        ktfmt().dropboxStyle().maxWidth(120)",
+				"    }",
+				"}");
+
+		setFile("src/main/kotlin/max-width.kt").toResource("kotlin/ktfmt/max-width.dirty");
+		gradleRunner().withArguments("spotlessApply").build();
+		assertFile("src/main/kotlin/max-width.kt").sameAsResource("kotlin/ktfmt/max-width-dropbox.clean");
+	}
 }
diff --git a/testlib/src/main/resources/kotlin/ktfmt/max-width-dropbox.clean b/testlib/src/main/resources/kotlin/ktfmt/max-width-dropbox.clean
@@ -0,0 +1,12 @@
+import a.*
+import a.b
+import a.b.c.*
+import kotlinx.android.synthetic.main.layout_name.*
+
+fun main() {}
+
+fun foo(param1: Any, param2: Any, param3: Any, param4: Any, param5: Any, param6: Any, param7: Any, param8: Any) {
+    a()
+    functionNameWithAlmost120SymbolsToValidateThatKtfmtNotBreakLineAtDefault100(param1, param2, param3, param4, param5)
+    return b
+}
diff --git a/testlib/src/main/resources/kotlin/ktfmt/max-width.clean b/testlib/src/main/resources/kotlin/ktfmt/max-width.clean
@@ -0,0 +1,12 @@
+import a.*
+import a.b
+import a.b.c.*
+import kotlinx.android.synthetic.main.layout_name.*
+
+fun main() {}
+
+fun foo(param1: Any, param2: Any, param3: Any, param4: Any, param5: Any, param6: Any, param7: Any, param8: Any) {
+  a()
+  functionNameWithAlmost120SymbolsToValidateThatKtfmtNotBreakLineAtDefault100(param1, param2, param3, param4, param5)
+  return b
+}
diff --git a/testlib/src/main/resources/kotlin/ktfmt/max-width.dirty b/testlib/src/main/resources/kotlin/ktfmt/max-width.dirty
@@ -0,0 +1,12 @@
+import a.*
+
+import kotlinx.android.synthetic.main.layout_name.*
+
+import a.b.c.*
+import a.b
+
+fun main() {}
+fun foo(param1: Any, param2: Any, param3: Any, param4: Any, param5: Any, param6: Any, param7: Any, param8: Any) {
+  a(); functionNameWithAlmost120SymbolsToValidateThatKtfmtNotBreakLineAtDefault100(param1, param2, param3, param4, param5)
+  return b
+}