Reworked filtering (#7)

* Reworked filtering

* Fix sonar

Author: ComputerDaddyGuy

CHANGELOG.md

@@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Changed
 - `PathUtils` removed, `PathPredicates` rework
 - Line extension: empty string is permitted
+- Filtering: split into distinct directories and files filters
 
 ---
 ## [0.0.4] - 2025-09-27

README.md

@@ -276,17 +276,23 @@ sorting/
 ## Filtering
 Files and directories can be selectively included or excluded using a custom `Predicate<Path>`.
 
-Filtering is **recursive by default**: directory's contents will always be traversed.
-However, if a directory does not match and none of its children match, the directory itself will not be displayed.
+Filtering is independant for files & directories. Files are filtered only if their parent directory pass the directory filter.
+If none of some directory's children match, the directory is still displayed.
 
 The `PathPredicates` class provides several ready-to-use methods for creating common predicates, as well as a builder for creating more advanced predicates.
 
 ```java
 // Example: Filtering.java
-var hasJavaExtensionPredicate = PathPredicates.builder().hasExtension("java").build();
+Predicate<Path> excludeDirWithNoJavaFiles = dir -> !PathPredicates.hasNameEndingWith(dir, "no_java_file");
+var isJavaFilePredicate = PathPredicates.builder().hasExtension("java").build();
+
 var prettyPrinter = FileTreePrettyPrinter.builder()
-    .customizeOptions(options -> options.filter(hasJavaExtensionPredicate))
-    .build();
+	.customizeOptions(
+		options -> options
+			.filterDirectories(excludeDirWithNoJavaFiles)
+			.filterFiles(hasJavaExtensionPredicate)
+	)
+	.build();
 ```
 ```
 filtering/

src/example/java/io/github/computerdaddyguy/jfiletreeprettyprinter/example/CompleteExample.java

@@ -0,0 +1,68 @@
+package io.github.computerdaddyguy.jfiletreeprettyprinter.example;
+
+import io.github.computerdaddyguy.jfiletreeprettyprinter.ChildLimitBuilder;
+import io.github.computerdaddyguy.jfiletreeprettyprinter.FileTreePrettyPrinter;
+import io.github.computerdaddyguy.jfiletreeprettyprinter.PathPredicates;
+import io.github.computerdaddyguy.jfiletreeprettyprinter.PrettyPrintOptions.Sorts;
+import java.nio.file.Path;
+import java.util.function.Function;
+
+public class CompleteExample {
+
+	public static void main(String[] args) {
+
+		var filterDir = PathPredicates.builder()
+			.pathTest(path -> !PathPredicates.hasName(path, ".git"))
+			.pathTest(path -> !PathPredicates.hasFullPathMatchingGlob(path, "**/.git"))
+			.pathTest(path -> !PathPredicates.hasFullPathMatchingGlob(path, "**/.github"))
+			.pathTest(path -> !PathPredicates.hasFullPathMatchingGlob(path, "**/.settings"))
+			.pathTest(path -> !PathPredicates.hasFullPathMatchingGlob(path, "**/src/example"))
+			.pathTest(path -> !PathPredicates.hasFullPathMatchingGlob(path, "**/src/test"))
+			.pathTest(path -> !PathPredicates.hasFullPathMatchingGlob(path, "**/target"))
+			.build();
+
+		var filterFiles = PathPredicates.builder()
+			.pathTest(path -> !PathPredicates.hasNameStartingWith(path, "."))
+			.pathTest(path -> {
+				if (PathPredicates.hasParentMatching(path, parent -> PathPredicates.hasName(parent, "jfiletreeprettyprinter"))) {
+					return PathPredicates.hasName(path, "FileTreePrettyPrinter.java");
+				}
+				return true;
+			})
+			.build();
+
+		var childLimitFunction = ChildLimitBuilder.builder()
+			.limit(path -> PathPredicates.hasFullPathMatchingGlob(path, "**/io/github/computerdaddyguy/jfiletreeprettyprinter/renderer"), 0)
+			.limit(path -> PathPredicates.hasFullPathMatchingGlob(path, "**/io/github/computerdaddyguy/jfiletreeprettyprinter/scanner"), 0)
+			.build();
+
+		Function<Path, String> lineExtension = path -> {
+			if (PathPredicates.hasName(path, "JfileTreePrettyPrinter-structure.png")) {
+				return "\t// This image";
+			} else if (PathPredicates.hasName(path, "FileTreePrettyPrinter.java")) {
+				return "\t// Main entry point";
+			} else if (PathPredicates.hasName(path, "README.md")) {
+				return "\t\t// You're reading at this!";
+			} else if (PathPredicates.hasName(path, "java")) {
+				return "";
+			}
+			return null;
+		};
+
+		var prettyPrinter = FileTreePrettyPrinter.builder()
+			.customizeOptions(
+				options -> options
+					.withEmojis(true)
+					.withCompactDirectories(true)
+					.filterDirectories(filterDir)
+					.filterFiles(filterFiles)
+					.withChildLimit(childLimitFunction)
+					.withLineExtension(lineExtension)
+					.sort(Sorts.DIRECTORY_FIRST)
+			)
+			.build();
+		var tree = prettyPrinter.prettyPrint(".");
+		System.out.println(tree);
+	}
+
+}

src/example/java/io/github/computerdaddyguy/jfiletreeprettyprinter/example/Filtering.java

@@ -2,13 +2,21 @@
 
 import io.github.computerdaddyguy.jfiletreeprettyprinter.FileTreePrettyPrinter;
 import io.github.computerdaddyguy.jfiletreeprettyprinter.PathPredicates;
+import java.nio.file.Path;
+import java.util.function.Predicate;
 
 public class Filtering {
 
 	public static void main(String[] args) {
+		Predicate<Path> excludeDirWithNoJavaFiles = dir -> !PathPredicates.hasNameEndingWith(dir, "no_java_file");
 		var hasJavaExtensionPredicate = PathPredicates.builder().hasExtension("java").build();
+
 		var prettyPrinter = FileTreePrettyPrinter.builder()
-			.customizeOptions(options -> options.filter(hasJavaExtensionPredicate))
+			.customizeOptions(
+				options -> options
+					.filterDirectories(excludeDirWithNoJavaFiles)
+					.filterFiles(hasJavaExtensionPredicate)
+			)
 			.build();
 
 		var tree = prettyPrinter.prettyPrint("src/example/resources/filtering");

src/main/java/io/github/computerdaddyguy/jfiletreeprettyprinter/PrettyPrintOptions.java

@@ -297,25 +297,37 @@ public PrettyPrintOptions sort(Comparator<Path> pathComparator) {
 
 	// ---------- Filtering ----------
 
-	@Nullable
-	private Predicate<Path> pathFilter = null;
+	private Predicate<Path> dirFilter = dir -> true;
+	private Predicate<Path> fileFilter = dir -> true;
 
 	@Override
-	@Nullable
 	public Predicate<Path> pathFilter() {
-		return pathFilter;
+		return path -> PathPredicates.isDirectory(path)
+			? dirFilter.test(path)
+			: fileFilter.test(path);
+	}
+
+	/**
+	 * Use a custom filter for retain only some directories.
+	 * 
+	 * Directories that do not pass this filter will not be displayed.
+	 * 
+	 * @param filter	The filter to apply on directories, cannot be <code>null</code>
+	 */
+	public PrettyPrintOptions filterDirectories(@Nullable Predicate<Path> filter) {
+		this.dirFilter = Objects.requireNonNull(filter, "filter is null");
+		return this;
 	}
 
 	/**
-	 * Use a custom filter for retain only some files and/or directories.
+	 * Use a custom filter for retain only some files.
+	 * 
+	 * Files that do not pass this filter will not be displayed.
 	 * 
-	 * Filtering is recursive by default: directory's contents will always be traversed.
-	 * However, if a directory does not match and none of its children match, the directory itself will not be displayed.
-	
-	 * @param filter	The filter, <code>null</code> to disable filtering
+	 * @param filter	The filter to apply on files, cannot be <code>null</code>
 	 */
-	public PrettyPrintOptions filter(@Nullable Predicate<Path> filter) {
-		this.pathFilter = filter;
+	public PrettyPrintOptions filterFiles(@Nullable Predicate<Path> filter) {
+		this.fileFilter = Objects.requireNonNull(filter, "filter is null");
 		return this;
 	}
 

src/main/java/io/github/computerdaddyguy/jfiletreeprettyprinter/renderer/DefaultTreeEntryRenderer.java

@@ -13,6 +13,7 @@
 import java.util.Objects;
 import java.util.Optional;
 import org.jspecify.annotations.NullMarked;
+import org.jspecify.annotations.Nullable;
 
 @NullMarked
 class DefaultTreeEntryRenderer implements TreeEntryRenderer {
@@ -41,25 +42,28 @@ private String renderTree(TreeEntry entry, Depth depth) {
 
 	private String renderDirectory(Depth depth, DirectoryEntry dirEntry, List<Path> compactPaths) {
 
-		Optional<String> extension = null;
+		boolean extensionEvaluated = false;
+		String extension = null;
+
 		if (options.areCompactDirectoriesUsed()
 			&& !depth.isRoot()
 			&& dirEntry.getEntries().size() == 1
 			&& dirEntry.getEntries().get(0) instanceof DirectoryEntry childDirEntry) {
 
 			extension = computeLineExtension(dirEntry.getDir());
-			if (extension.isEmpty()) {
+			extensionEvaluated = true;
+			if (extension == null) {
 				var newCompactPaths = new ArrayList<>(compactPaths);
 				newCompactPaths.add(childDirEntry.getDir());
 				return renderDirectory(depth, childDirEntry, newCompactPaths);
 			}
 		}
 
 		var line = lineRenderer.renderDirectoryBegin(depth, dirEntry, compactPaths);
-		if (extension == null) {
+		if (!extensionEvaluated) {
 			extension = computeLineExtension(dirEntry.getDir());
 		}
-		line += extension.orElse("");
+		line += Optional.ofNullable(extension).orElse("");
 
 		var childIt = dirEntry.getEntries().iterator();
 
@@ -81,16 +85,17 @@ private String renderDirectory(Depth depth, DirectoryEntry dirEntry, List<Path>
 		return line + childLines.toString();
 	}
 
-	private Optional<String> computeLineExtension(Path path) {
+	@Nullable
+	private String computeLineExtension(Path path) {
 		if (options.getLineExtension() == null) {
-			return Optional.empty();
+			return null;
 		}
-		return Optional.ofNullable(options.getLineExtension().apply(path));
+		return options.getLineExtension().apply(path);
 	}
 
 	private String renderFile(Depth depth, FileEntry fileEntry) {
 		var line = lineRenderer.renderFile(depth, fileEntry);
-		line += computeLineExtension(fileEntry.getFile()).orElse("");
+		line += Optional.ofNullable(computeLineExtension(fileEntry.getFile())).orElse("");
 		return line;
 	}
 

src/main/java/io/github/computerdaddyguy/jfiletreeprettyprinter/scanner/DefaultPathToTreeScanner.java

@@ -1,6 +1,5 @@
 package io.github.computerdaddyguy.jfiletreeprettyprinter.scanner;
 
-import io.github.computerdaddyguy.jfiletreeprettyprinter.PathPredicates;
 import io.github.computerdaddyguy.jfiletreeprettyprinter.scanner.TreeEntry.DirectoryEntry;
 import io.github.computerdaddyguy.jfiletreeprettyprinter.scanner.TreeEntry.FileEntry;
 import io.github.computerdaddyguy.jfiletreeprettyprinter.scanner.TreeEntry.MaxDepthReachEntry;
@@ -35,14 +34,14 @@ public TreeEntry scan(Path fileOrDir) {
 	}
 
 	@Nullable
-	private TreeEntry handle(int depth, Path fileOrDir, @Nullable Predicate<Path> filter) {
+	private TreeEntry handle(int depth, Path fileOrDir, Predicate<Path> filter) {
 		return fileOrDir.toFile().isDirectory()
 			? handleDirectory(depth, fileOrDir, filter)
 			: handleFile(fileOrDir);
 	}
 
 	@Nullable
-	private TreeEntry handleDirectory(int depth, Path dir, @Nullable Predicate<Path> filter) {
+	private TreeEntry handleDirectory(int depth, Path dir, Predicate<Path> filter) {
 
 		if (depth >= options.getMaxDepth()) {
 			var maxDepthEntry = new MaxDepthReachEntry(depth);
@@ -58,15 +57,10 @@ private TreeEntry handleDirectory(int depth, Path dir, @Nullable Predicate<Path>
 			throw new UncheckedIOException("Unable to list files for directory: " + dir, e);
 		}
 
-		// Filter is active and no children match
-		if (depth > 0 && filter != null && childEntries.isEmpty() && !filter.test(dir)) {
-			return null; // Do no show this directory at all
-		}
-
 		return new DirectoryEntry(dir, childEntries);
 	}
 
-	private List<TreeEntry> handleDirectoryChildren(int depth, Path dir, Iterator<Path> pathIterator, @Nullable Predicate<Path> filter) {
+	private List<TreeEntry> handleDirectoryChildren(int depth, Path dir, Iterator<Path> pathIterator, Predicate<Path> filter) {
 
 		var childEntries = new ArrayList<TreeEntry>();
 		int maxChildEntries = options.getChildLimit().applyAsInt(dir);
@@ -95,39 +89,29 @@ private List<TreeEntry> handleDirectoryChildren(int depth, Path dir, Iterator<Pa
 		return childEntries;
 	}
 
-	private List<TreeEntry> handleLeftOverChildren(int depth, Iterator<Path> pathIterator, @Nullable Predicate<Path> filter) {
+	private List<TreeEntry> handleLeftOverChildren(int depth, Iterator<Path> pathIterator, Predicate<Path> filter) {
 		var childEntries = new ArrayList<TreeEntry>();
 
-		if (filter == null) {
-			var skippedChildren = new ArrayList<Path>();
-			pathIterator.forEachRemaining(skippedChildren::add);
+		var skippedChildren = new ArrayList<Path>();
+		while (pathIterator.hasNext()) {
+			var child = pathIterator.next();
+			var childEntry = handle(depth + 1, child, filter);
+			if (childEntry != null) { // Is null if no children file is retained by filter
+				skippedChildren.add(child);
+			}
+		}
+		if (!skippedChildren.isEmpty()) {
 			var childrenSkippedEntry = new SkippedChildrenEntry(skippedChildren);
 			childEntries.add(childrenSkippedEntry);
-		} else {
-			var skippedChildren = new ArrayList<Path>();
-			while (pathIterator.hasNext()) {
-				var child = pathIterator.next();
-				var childEntry = handle(depth + 1, child, filter);
-				if (childEntry != null) { // Is null if no children file is retained by filter
-					skippedChildren.add(child);
-				}
-			}
-			if (!skippedChildren.isEmpty()) {
-				var childrenSkippedEntry = new SkippedChildrenEntry(skippedChildren);
-				childEntries.add(childrenSkippedEntry);
-			}
 		}
 
 		return childEntries;
 	}
 
-	private Iterator<Path> directoryStreamToIterator(DirectoryStream<Path> childrenStream, @Nullable Predicate<Path> filter) {
-		var stream = StreamSupport.stream(childrenStream.spliterator(), false);
-		if (filter != null) {
-			var recursiveFilter = PathPredicates.builder().isDirectory().build().or(filter);
-			stream = stream.filter(recursiveFilter);
-		}
-		return stream
+	private Iterator<Path> directoryStreamToIterator(DirectoryStream<Path> childrenStream, Predicate<Path> filter) {
+		return StreamSupport
+			.stream(childrenStream.spliterator(), false)
+			.filter(filter)
 			.sorted(options.pathComparator())
 			.iterator();
 	}

src/main/java/io/github/computerdaddyguy/jfiletreeprettyprinter/scanner/ScanningOptions.java

@@ -5,7 +5,6 @@
 import java.util.function.Predicate;
 import java.util.function.ToIntFunction;
 import org.jspecify.annotations.NullMarked;
-import org.jspecify.annotations.Nullable;
 
 @NullMarked
 public interface ScanningOptions {
@@ -16,7 +15,6 @@ public interface ScanningOptions {
 
 	Comparator<Path> pathComparator();
 
-	@Nullable
 	Predicate<Path> pathFilter();
 
 }

src/test/java/io/github/computerdaddyguy/jfiletreeprettyprinter/FileTreePrettyPrinterTest.java

@@ -21,15 +21,4 @@ void prettyPrint_by_path_and_string_are_same() {
 		assertThat(printer.prettyPrint(path)).isEqualTo(printer.prettyPrint(path.toString()));
 	}
 
-	@Test
-	void prettyPrintWithFilter_by_path_and_string_are_same() {
-		var path = FileStructures.simpleDirectoryWithFilesAndFolders(root, 3, 3);
-
-		FileTreePrettyPrinter printer = FileTreePrettyPrinter.builder()
-			.customizeOptions(options -> options.filter(PathPredicates::isFile))
-			.build();
-
-		assertThat(printer.prettyPrint(path)).isEqualTo(printer.prettyPrint(path.toString()));
-	}
-
 }