Extension of FormatterFunc accepting source file as parameter.

CHANGES.md

@@ -7,6 +7,7 @@ You might be looking for:
 
 ### Version 1.15.0-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/))
 
+* Integrated Eclipse WTP formatter ([#290](https://github.com/diffplug/spotless/pull/290))
 * Updated JSR305 annotation from 3.0.0 to 3.0.2 ([#274](https://github.com/diffplug/spotless/pull/274))
 * Migrated from FindBugs annotations 3.0.0 to SpotBugs annotations 3.1.6 ([#274](https://github.com/diffplug/spotless/pull/274))
 * `Formatter` now implements `AutoCloseable`.  This means that users of `Formatter` are expected to use the try-with-resources pattern.  The reason for this change is so that `FormatterFunc.Closeable` actually works. ([#284](https://github.com/diffplug/spotless/pull/284))

lib-extra/src/main/java/com/diffplug/spotless/extra/wtp/WtpEclipseFormatterStep.java

@@ -15,6 +15,7 @@
  */
 package com.diffplug.spotless.extra.wtp;
 
+import java.io.File;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.util.Properties;
@@ -39,30 +40,30 @@ public static String defaultVersion() {
 
 	/** Provides default configuration for CSSformatter */
 	public static EclipseBasedStepBuilder createCssBuilder(Provisioner provisioner) {
-		return new EclipseBasedStepBuilder(NAME, " - css", provisioner, state -> apply("EclipseCssFormatterStepImpl", state));
+		return new EclipseBasedStepBuilder(NAME, " - css", provisioner, state -> applyWithoutFile("EclipseCssFormatterStepImpl", state));
 	}
 
 	/** Provides default configuration for HTML formatter */
 	public static EclipseBasedStepBuilder createHtmlBuilder(Provisioner provisioner) {
-		return new EclipseBasedStepBuilder(NAME, " - html", provisioner, state -> apply("EclipseHtmlFormatterStepImpl", state));
+		return new EclipseBasedStepBuilder(NAME, " - html", provisioner, state -> applyWithoutFile("EclipseHtmlFormatterStepImpl", state));
 	}
 
 	/** Provides default configuration for Java Script formatter */
 	public static EclipseBasedStepBuilder createJsBuilder(Provisioner provisioner) {
-		return new EclipseBasedStepBuilder(NAME, " - js", provisioner, state -> apply("EclipseJsFormatterStepImpl", state));
+		return new EclipseBasedStepBuilder(NAME, " - js", provisioner, state -> applyWithoutFile("EclipseJsFormatterStepImpl", state));
 	}
 
 	/** Provides default configuration for JSON formatter */
 	public static EclipseBasedStepBuilder createJsonBuilder(Provisioner provisioner) {
-		return new EclipseBasedStepBuilder(NAME, " - json", provisioner, state -> apply("EclipseJsonFormatterStepImpl", state));
+		return new EclipseBasedStepBuilder(NAME, " - json", provisioner, state -> applyWithoutFile("EclipseJsonFormatterStepImpl", state));
 	}
 
 	/** Provides default configuration for XML formatter */
 	public static EclipseBasedStepBuilder createXmlBuilder(Provisioner provisioner) {
-		return new EclipseBasedStepBuilder(NAME, " - xml", provisioner, state -> apply("EclipseXmlFormatterStepImpl", state));
+		return new EclipseBasedStepBuilder(NAME, " - xml", provisioner, state -> applyWithFile("EclipseXmlFormatterStepImpl", state));
 	}
 
-	private static FormatterFunc apply(String className, EclipseBasedStepBuilder.State state) throws Exception {
+	private static FormatterFunc applyWithoutFile(String className, EclipseBasedStepBuilder.State state) throws Exception {
 		Class<?> formatterClazz = state.loadClass(FORMATTER_PACKAGE + className);
 		Object formatter = formatterClazz.getConstructor(Properties.class).newInstance(state.getPreferences());
 		Method method = formatterClazz.getMethod(FORMATTER_METHOD, String.class);
@@ -77,4 +78,27 @@ private static FormatterFunc apply(String className, EclipseBasedStepBuilder.Sta
 		};
 	}
 
+	private static FormatterFuncWithFile applyWithFile(String className, EclipseBasedStepBuilder.State state) throws Exception {
+		Class<?> formatterClazz = state.loadClass(FORMATTER_PACKAGE + className);
+		Object formatter = formatterClazz.getConstructor(Properties.class).newInstance(state.getPreferences());
+		Method method = formatterClazz.getMethod(FORMATTER_METHOD, String.class, String.class);
+		return (input, source) -> {
+			try {
+				return (String) method.invoke(formatter, input, source.getAbsolutePath());
+			} catch (InvocationTargetException exceptionWrapper) {
+				Throwable throwable = exceptionWrapper.getTargetException();
+				Exception exception = (throwable instanceof Exception) ? (Exception) throwable : null;
+				throw (null == exception) ? exceptionWrapper : exception;
+			}
+		};
+	}
+
+	private static interface FormatterFuncWithFile extends FormatterFunc {
+		@Override
+		default String apply(String input) throws Exception {
+			throw new UnsupportedOperationException("Formatter requires file path of source.");
+		}
+
+		public String apply(String input, File source) throws Exception;
+	}
 }

lib-extra/src/test/java/com/diffplug/spotless/extra/wtp/EclipseWtpFormatterStepTest.java

@@ -25,7 +25,6 @@
 import java.util.Properties;
 import java.util.function.Consumer;
 import java.util.function.Function;
-import java.util.stream.Collectors;
 
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -73,8 +72,7 @@ private WTP(String input, final String expectation, Function<Provisioner, Eclips
 
 	@Parameters(name = "{0}")
 	public static Iterable<WTP> data() {
-		//TODO: XML is excluded. How to provide base location will be addressed by separate PR.
-		return Arrays.asList(WTP.values()).stream().filter(e -> e != WTP.XML).collect(Collectors.toList());
+		return Arrays.asList(WTP.values());
 	}
 
 	@Parameter(0)

lib/src/main/java/com/diffplug/spotless/FormatterFunc.java

@@ -15,11 +15,26 @@
  */
 package com.diffplug.spotless;
 
+import java.io.File;
 import java.util.Objects;
 
-/** A `Function<String, String>` which can throw an exception. */
-public interface FormatterFunc extends ThrowingEx.Function<String, String> {
-	/** A `Function<String, String>` whose implementation requires a resource which should be released when the function is no longer needed. */
+/**
+ * A `Function<String, String>` which can throw an exception.
+ * Also the `BiFunction<String, File, String>` is supported, whereas the default
+ * implementation only requires the `Function<String, String>` implementation.
+ */
+public interface FormatterFunc
+		extends ThrowingEx.Function<String, String>, ThrowingEx.BiFunction<String, File, String> {
+
+	@Override
+	default String apply(String input, File source) throws Exception {
+		return apply(input);
+	}
+
+	/**
+	 * `Function<String, String>` and `BiFunction<String, File, String>` whose implementation
+	 * requires a resource which should be released when the function is no longer needed.
+	 */
 	interface Closeable extends FormatterFunc, AutoCloseable {
 		@Override
 		void close();
@@ -34,11 +49,17 @@ public void close() {
 					ThrowingEx.run(closeable::close);
 				}
 
+				@Override
+				public String apply(String input, File source) throws Exception {
+					return function.apply(Objects.requireNonNull(input), Objects.requireNonNull(source));
+				}
+
 				@Override
 				public String apply(String input) throws Exception {
 					return function.apply(Objects.requireNonNull(input));
 				}
 			};
 		}
 	}
+
 }

lib/src/main/java/com/diffplug/spotless/FormatterStepImpl.java

@@ -75,7 +75,7 @@ protected String format(State state, String rawUnix, File file) throws Exception
 			if (formatter == null) {
 				formatter = stateToFormatter.apply(state());
 			}
-			return formatter.apply(rawUnix);
+			return formatter.apply(rawUnix, file);
 		}
 
 		void cleanupFormatterFunc() {
@@ -107,7 +107,7 @@ protected String format(Integer state, String rawUnix, File file) throws Excepti
 					throw new AssertionError("NeverUpToDate does not support FormatterFunc.Closeable.  See https://github.com/diffplug/spotless/pull/284");
 				}
 			}
-			return formatter.apply(rawUnix);
+			return formatter.apply(rawUnix, file);
 		}
 	}
 }

lib/src/main/java/com/diffplug/spotless/ThrowingEx.java

@@ -31,6 +31,12 @@ public interface Function<T, R> {
 		R apply(T input) throws Exception;
 	}
 
+	/** A bi-function that can throw any exception. */
+	@FunctionalInterface
+	public interface BiFunction<T1, T2, R> {
+		R apply(T1 input1, T2 input2) throws Exception;
+	}
+
 	/** A supplier that can throw any exception. */
 	@FunctionalInterface
 	public interface Supplier<T> {