Allow custom separator for years in license header

CHANGES.md

@@ -7,6 +7,8 @@ You might be looking for:
 
 ### Version 1.10.0-SNAPSHOT - TBD (javadoc [lib](https://diffplug.github.io/spotless/javadoc/spotless-lib/snapshot/) [lib-extra](https://diffplug.github.io/spotless/javadoc/spotless-lib-extra/snapshot/), [snapshot repo](https://oss.sonatype.org/content/repositories/snapshots/com/diffplug/spotless/))
 
+* LicenseHeaderStep now supports customizing the year range separator in copyright notices. ([#199](https://github.com/diffplug/spotless/pull/199))
+
 ### Version 1.9.0 - February 5th 2018 (javadoc [lib](https://diffplug.github.io/spotless/javadoc/spotless-lib/1.9.0/) [lib-extra](https://diffplug.github.io/spotless/javadoc/spotless-lib-extra/1.9.0/), artifact [lib]([jcenter](https://bintray.com/diffplug/opensource/spotless-lib), [lib-extra]([jcenter](https://bintray.com/diffplug/opensource/spotless-lib-extra)))
 
 * Updated default ktlint from 0.6.1 to 0.14.0

lib/src/main/java/com/diffplug/spotless/generic/LicenseHeaderStep.java

@@ -25,6 +25,8 @@
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
+import javax.annotation.Nullable;
+
 import com.diffplug.spotless.FormatterStep;
 import com.diffplug.spotless.LineEnding;
 
@@ -33,6 +35,7 @@ public final class LicenseHeaderStep implements Serializable {
 	private static final long serialVersionUID = 1L;
 
 	private static final String NAME = "licenseHeader";
+	private static final String DEFAULT_YEAR_DELIMITER = "-";
 
 	private final String licenseHeader;
 	private final Pattern delimiterPattern;
@@ -44,10 +47,15 @@ public final class LicenseHeaderStep implements Serializable {
 
 	/** Creates a FormatterStep which forces the start of each file to match a license header. */
 	public static FormatterStep createFromHeader(String licenseHeader, String delimiter) {
+		return createFromHeader(licenseHeader, delimiter, null);
+	}
+
+	public static FormatterStep createFromHeader(String licenseHeader, String delimiter,
+			@Nullable String yearSeparator) {
 		Objects.requireNonNull(licenseHeader, "licenseHeader");
 		Objects.requireNonNull(delimiter, "delimiter");
 		return FormatterStep.create(LicenseHeaderStep.NAME,
-				new LicenseHeaderStep(licenseHeader, delimiter),
+				new LicenseHeaderStep(licenseHeader, delimiter, yearSeparator),
 				step -> step::format);
 	}
 
@@ -56,20 +64,36 @@ public static FormatterStep createFromHeader(String licenseHeader, String delimi
 	 * contained in the given file.
 	 */
 	public static FormatterStep createFromFile(File licenseHeaderFile, Charset encoding, String delimiter) {
+		return createFromFile(licenseHeaderFile, encoding, delimiter, null);
+	}
+
+	/**
+	 * Creates a FormatterStep which forces the start of each file to match the license header
+	 * contained in the given file.
+	 */
+	public static FormatterStep createFromFile(File licenseHeaderFile, Charset encoding, String delimiter,
+			@Nullable String yearSeparator) {
 		Objects.requireNonNull(licenseHeaderFile, "licenseHeaderFile");
 		Objects.requireNonNull(encoding, "encoding");
 		Objects.requireNonNull(delimiter, "delimiter");
 		return FormatterStep.createLazy(LicenseHeaderStep.NAME,
-				() -> new LicenseHeaderStep(licenseHeaderFile, encoding, delimiter),
+				() -> new LicenseHeaderStep(licenseHeaderFile, encoding, delimiter, yearSeparator),
 				step -> step::format);
 	}
 
 	public static String name() {
 		return NAME;
 	}
 
+	public static String defaultYearDelimiter() {
+		return DEFAULT_YEAR_DELIMITER;
+	}
+
 	/** The license that we'd like enforced. */
-	private LicenseHeaderStep(String licenseHeader, String delimiter) {
+	private LicenseHeaderStep(String licenseHeader, String delimiter, @Nullable String yearSeparator) {
+		if (yearSeparator == null) {
+			yearSeparator = defaultYearDelimiter();
+		}
 		if (delimiter.contains("\n")) {
 			throw new IllegalArgumentException("The delimiter must not contain any newlines.");
 		}
@@ -86,13 +110,13 @@ private LicenseHeaderStep(String licenseHeader, String delimiter) {
 			this.licenseHeaderBeforeYearToken = licenseHeader.substring(0, yearTokenIndex);
 			this.licenseHeaderAfterYearToken = licenseHeader.substring(yearTokenIndex + 5, licenseHeader.length());
 			this.licenseHeaderWithYearTokenReplaced = licenseHeader.replace("$YEAR", String.valueOf(YearMonth.now().getYear()));
-			this.yearMatcherPattern = Pattern.compile("[0-9]{4}(-[0-9]{4})?");
+			this.yearMatcherPattern = Pattern.compile("[0-9]{4}(" + Pattern.quote(yearSeparator) + "[0-9]{4})?");
 		}
 	}
 
 	/** Reads the license file from the given file. */
-	private LicenseHeaderStep(File licenseFile, Charset encoding, String delimiter) throws IOException {
-		this(new String(Files.readAllBytes(licenseFile.toPath()), encoding), delimiter);
+	private LicenseHeaderStep(File licenseFile, Charset encoding, String delimiter, @Nullable String yearSeparator) throws IOException {
+		this(new String(Files.readAllBytes(licenseFile.toPath()), encoding), delimiter, yearSeparator);
 	}
 
 	/** Formats the given string. */

plugin-gradle/CHANGES.md

@@ -2,6 +2,8 @@
 
 ### Version 3.10.0-SNAPSHOT - TBD ([javadoc](https://diffplug.github.io/spotless/javadoc/snapshot/), [snapshot](https://oss.sonatype.org/content/repositories/snapshots/com/diffplug/spotless/spotless-plugin-gradle/))
 
+* LicenseHeaderStep now supports customizing the year range separator in copyright notices. ([#199](https://github.com/diffplug/spotless/pull/199)
+
 ### Version 3.9.0 - February 5th 2018 ([javadoc](https://diffplug.github.io/spotless/javadoc/spotless-plugin-gradle/3.9.0/), [jcenter](https://bintray.com/diffplug/opensource/spotless-plugin-gradle/3.9.0))
 
 * Updated default ktlint from 0.6.1 to 0.14.0

plugin-gradle/README.md

@@ -307,10 +307,22 @@ The `licenseHeader` and `licenseHeaderFile` steps will generate license headers
 * A generated license header will _not_ be updated when
   * a single year is already present, e.g.
   `/* Licensed under Apache-2.0 1990. */`
-  * a hyphen-separated year range is already present, e.g.
+  * a year range is already present, e.g.
   `/* Licensed under Apache-2.0 1990-2003. */`
   * the `$YEAR` token is otherwise missing
 
+The separator for the year range defaults to the hyphen character, e.g `1990-2003`, but can be customized with the `yearSeparator` property.
+
+For instance, the following configuration treats `1990, 2003` as a valid year range.
+
+```gradle
+spotless {
+  format java {
+     licenseHeader(''Licensed under Apache-2.0 $YEAR').yearSeparator(', ')
+  }
+}
+```
+
 
 <a name="custom"></a>
 

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

@@ -345,26 +345,90 @@ public void indentWithTabs() {
 		indentWithTabs(4);
 	}
 
+	abstract class LicenseHeaderConfig {
+
+		String delimiter;
+		String yearSeparator;
+
+		public LicenseHeaderConfig(String delimiter) {
+			this.delimiter = Objects.requireNonNull(delimiter, "delimiter");
+		}
+
+		/**
+		 * @param delimiter
+		 *            Spotless will look for a line that starts with this regular expression pattern to know what the "top" is.
+		 */
+		public LicenseHeaderConfig delimiter(String delimiter) {
+			this.delimiter = Objects.requireNonNull(delimiter, "delimiter");
+			replaceStep(createStep());
+			return this;
+		}
+
+		/**
+		 * @param yearSeparator
+		 *           The characters used to separate the first and last years in multi years patterns.
+		 */
+		public LicenseHeaderConfig yearSeparator(String yearSeparator) {
+			this.yearSeparator = Objects.requireNonNull(yearSeparator, "yearSeparator");
+			replaceStep(createStep());
+			return this;
+		}
+
+		abstract FormatterStep createStep();
+	}
+
+	class LicenseStringHeaderConfig extends LicenseHeaderConfig {
+
+		private String header;
+
+		LicenseStringHeaderConfig(String delimiter, String header) {
+			super(delimiter);
+			this.header = Objects.requireNonNull(header, "header");
+		}
+
+		FormatterStep createStep() {
+			return LicenseHeaderStep.createFromHeader(header, delimiter, yearSeparator);
+		}
+	}
+
+	class LicenseFileHeaderConfig extends LicenseHeaderConfig {
+
+		private Object headerFile;
+
+		LicenseFileHeaderConfig(String delimiter, Object headerFile) {
+			super(delimiter);
+			this.headerFile = Objects.requireNonNull(headerFile, "headerFile");
+		}
+
+		FormatterStep createStep() {
+			return LicenseHeaderStep
+					.createFromFile(getProject().file(headerFile), getEncoding(), delimiter,
+							yearSeparator);
+		}
+	}
+
 	/**
 	 * @param licenseHeader
-	 *            Content that should be at the top of every file
+	 *            Content that should be at the top of every file.
 	 * @param delimiter
-	 *            Spotless will look for a line that starts with this to know what the "top" is.
+	 *            Spotless will look for a line that starts with this regular expression pattern to know what the "top" is.
 	 */
-	public void licenseHeader(String licenseHeader, String delimiter) {
-		addStep(LicenseHeaderStep.createFromHeader(licenseHeader, delimiter));
+	public LicenseHeaderConfig licenseHeader(String licenseHeader, String delimiter) {
+		LicenseHeaderConfig config = new LicenseStringHeaderConfig(delimiter, licenseHeader);
+		addStep(config.createStep());
+		return config;
 	}
 
 	/**
 	 * @param licenseHeaderFile
-	 *            Content that should be at the top of every file
+	 *            Content that should be at the top of every file.
 	 * @param delimiter
-	 *            Spotless will look for a line that starts with this to know what the "top" is.
+	 *            Spotless will look for a line that starts with this regular expression pattern to know what the "top" is.
 	 */
-	public void licenseHeaderFile(Object licenseHeaderFile, String delimiter) {
-		Objects.requireNonNull(licenseHeaderFile, "licenseHeaderFile");
-		Objects.requireNonNull(delimiter, "delimiter");
-		addStep(LicenseHeaderStep.createFromFile(getProject().file(licenseHeaderFile), getEncoding(), delimiter));
+	public LicenseHeaderConfig licenseHeaderFile(Object licenseHeaderFile, String delimiter) {
+		LicenseHeaderConfig config = new LicenseFileHeaderConfig(delimiter, licenseHeaderFile);
+		addStep(config.createStep());
+		return config;
 	}
 
 	/** Sets up a format task according to the values in this extension. */

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

@@ -55,12 +55,12 @@ public void excludeJava(boolean excludeJava) {
 		this.excludeJava = excludeJava;
 	}
 
-	public void licenseHeader(String licenseHeader) {
-		licenseHeader(licenseHeader, JavaExtension.LICENSE_HEADER_DELIMITER);
+	public LicenseHeaderConfig licenseHeader(String licenseHeader) {
+		return licenseHeader(licenseHeader, JavaExtension.LICENSE_HEADER_DELIMITER);
 	}
 
-	public void licenseHeaderFile(Object licenseHeaderFile) {
-		licenseHeaderFile(licenseHeaderFile, JavaExtension.LICENSE_HEADER_DELIMITER);
+	public LicenseHeaderConfig licenseHeaderFile(Object licenseHeaderFile) {
+		return licenseHeaderFile(licenseHeaderFile, JavaExtension.LICENSE_HEADER_DELIMITER);
 	}
 
 	/** Method interface has been changed to

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

@@ -46,12 +46,12 @@ public JavaExtension(SpotlessExtension rootExtension) {
 	// testlib/src/test/java/com/diffplug/spotless/generic/LicenseHeaderStepTest.java as well
 	static final String LICENSE_HEADER_DELIMITER = "package ";
 
-	public void licenseHeader(String licenseHeader) {
-		licenseHeader(licenseHeader, LICENSE_HEADER_DELIMITER);
+	public LicenseHeaderConfig licenseHeader(String licenseHeader) {
+		return licenseHeader(licenseHeader, LICENSE_HEADER_DELIMITER);
 	}
 
-	public void licenseHeaderFile(Object licenseHeaderFile) {
-		licenseHeaderFile(licenseHeaderFile, LICENSE_HEADER_DELIMITER);
+	public LicenseHeaderConfig licenseHeaderFile(Object licenseHeaderFile) {
+		return licenseHeaderFile(licenseHeaderFile, LICENSE_HEADER_DELIMITER);
 	}
 
 	/** Method interface has been changed to

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

@@ -33,12 +33,12 @@ public KotlinExtension(SpotlessExtension rootExtension) {
 		super(rootExtension);
 	}
 
-	public void licenseHeader(String licenseHeader) {
-		licenseHeader(licenseHeader, LICENSE_HEADER_DELIMITER);
+	public LicenseHeaderConfig licenseHeader(String licenseHeader) {
+		return licenseHeader(licenseHeader, LICENSE_HEADER_DELIMITER);
 	}
 
-	public void licenseHeaderFile(Object licenseHeaderFile) {
-		licenseHeaderFile(licenseHeaderFile, LICENSE_HEADER_DELIMITER);
+	public LicenseHeaderConfig licenseHeaderFile(Object licenseHeaderFile) {
+		return licenseHeaderFile(licenseHeaderFile, LICENSE_HEADER_DELIMITER);
 	}
 
 	/** Adds the specified version of [ktlint](https://github.com/shyiko/ktlint). */

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

@@ -17,13 +17,15 @@
 
 import java.io.File;
 import java.io.IOException;
+import java.time.YearMonth;
 
 import org.assertj.core.api.Assertions;
 import org.junit.Assert;
 import org.junit.Test;
 
 public class KotlinExtensionTest extends GradleIntegrationTest {
 	private static final String HEADER = "// License Header";
+	private static final String HEADER_WITH_YEAR = "// License Header $YEAR";
 
 	@Test
 	public void integration() throws IOException {
@@ -72,4 +74,66 @@ public void testWithHeader() throws IOException {
 				// Make sure that no additional stuff got added to the file.
 				.contains(HEADER + '\n' + original);
 	}
+
+	@Test
+	public void testWithCustomHeaderSeparator() throws IOException {
+		write("build.gradle",
+				"plugins {",
+				"    id 'nebula.kotlin' version '1.0.6'",
+				"    id 'com.diffplug.gradle.spotless'",
+				"}",
+				"repositories { mavenCentral() }",
+				"spotless {",
+				"    kotlin {",
+				"        licenseHeader ('" + HEADER + "', '@file')",
+				"        ktlint()",
+				"    }",
+				"}");
+		final File testFile = write("src/main/kotlin/test.kt", getTestResource("kotlin/licenseheader/KotlinCodeWithoutHeader.test"));
+		final String original = read(testFile.toPath());
+		gradleRunner().withArguments("spotlessApply").build();
+		final String result = read(testFile.toPath());
+		Assertions
+				.assertThat(result)
+				// Make sure the header gets added.
+				.startsWith(HEADER)
+				// Make sure that the rest of the file is still there with nothing removed.
+				.endsWith(original)
+				// Make sure that no additional stuff got added to the file.
+				.contains(HEADER + '\n' + original);
+	}
+
+	@Test
+	public void testWithNonStandardYearSeparator() throws IOException {
+		write("build.gradle",
+				"plugins {",
+				"    id 'nebula.kotlin' version '1.0.6'",
+				"    id 'com.diffplug.gradle.spotless'",
+				"}",
+				"repositories { mavenCentral() }",
+				"spotless {",
+				"    kotlin {",
+				"        licenseHeader('" + HEADER_WITH_YEAR + "').yearSeparator(', ')",
+				"        ktlint()",
+				"    }",
+				"}");
+
+		final File testFile = write("src/main/kotlin/test.kt", getTestResource("kotlin/licenseheader/KotlinCodeWithMultiYearHeader.test"));
+		final String original = read(testFile.toPath());
+		final File testFile2 = write("src/main/kotlin/test2.kt", getTestResource("kotlin/licenseheader/KotlinCodeWithMultiYearHeader2.test"));
+		final String original2 = read(testFile.toPath());
+		gradleRunner().withArguments("spotlessApply").build();
+		final String result = read(testFile.toPath());
+		final String result2 = read(testFile2.toPath());
+
+		Assertions
+				.assertThat(result)
+				// Make sure the a "valid" header isn't changed
+				.contains("// License Header 2012, 2014");
+
+		Assertions
+				.assertThat(result2)
+				// Make sure that an "invalid" header is rewritten
+				.startsWith(HEADER_WITH_YEAR.replace("$YEAR", String.valueOf(YearMonth.now().getYear())));
+	}
 }

plugin-gradle/src/test/resources/kotlin/licenseheader/KotlinCodeWithMultiYearHeader.test

@@ -0,0 +1,5 @@
+// License Header 2012, 2014
+@file:JvmName("SomeFileName")
+package my.test
+
+object AnObject

plugin-gradle/src/test/resources/kotlin/licenseheader/KotlinCodeWithMultiYearHeader2.test

@@ -0,0 +1,5 @@
+// License Header 2012-2014
+@file:JvmName("SomeFileName")
+package my.test
+
+object AnObject