Implement review suggestions

Author: Erik

lib-extra/src/main/java/com/diffplug/spotless/extra/GitRatchet.java

@@ -69,7 +69,7 @@ public boolean isClean(Project project, ObjectId treeSha, File file) throws IOEx
 	 * true if that file is clean relative to that tree.  A naive implementation of this
 	 * could be verrrry slow, so the rest of this is about speeding this up.
 	 */
-	public boolean isClean(Project project, ObjectId treeSha, String relativePath) throws IOException {
+	public boolean isClean(Project project, ObjectId treeSha, String relativePathUnix) throws IOException {
 		Repository repo = repositoryFor(project);
 
 		// TODO: should be cached-per-repo if it is thread-safe, or per-repo-per-thread if it is not
@@ -81,7 +81,7 @@ public boolean isClean(Project project, ObjectId treeSha, String relativePath) t
 			treeWalk.addTree(new DirCacheIterator(dirCache));
 			treeWalk.addTree(new FileTreeIterator(repo));
 			treeWalk.setFilter(AndTreeFilter.create(
-					PathFilter.create(relativePath),
+					PathFilter.create(relativePathUnix),
 					new IndexDiffFilter(INDEX, WORKDIR)));
 
 			if (!treeWalk.next()) {
@@ -108,7 +108,7 @@ public boolean isClean(Project project, ObjectId treeSha, String relativePath) t
 						} else if (treeEqualsIndex) {
 							// this means they are all equal to each other, which should never happen
 							// the IndexDiffFilter should keep those out of the TreeWalk entirely
-							throw new IllegalStateException("Index status for " + relativePath + " against treeSha " + treeSha + " is invalid.");
+							throw new IllegalStateException("Index status for " + relativePathUnix + " against treeSha " + treeSha + " is invalid.");
 						} else {
 							// they are all unique
 							// we have to check manually

plugin-maven/src/main/java/com/diffplug/spotless/maven/AbstractSpotlessMojo.java

@@ -195,7 +195,7 @@ private List<File> collectFilesFromGit(FormatterFactory formatterFactory, String
 		for (String file : withNormalizedFileSeparators(dirtyFiles)) {
 			if (includePatterns.matches(file, true)) {
 				if (!excludePatterns.matches(file, true)) {
-					result.add(Paths.get(baseDir.getPath(), file).toFile());
+					result.add(new File(baseDir.getPath(), file));
 				}
 			}
 		}