Checkout: better directory handling

When checking out a file into the working tree ensure that all parent
directories of the file below the working tree root are actually
directories and do exist before we try to create the file.

When multiple files are to be checked out (or even a whole tree), this
may check the same directories over and over again. Asking the file
system every time for file attributes is a potentially expensive
operation. As a remedy, introduce an in-memory cache of directory
states for a particular check-out operation.

Apply the same fix also in the ResolveMerger, which may also check out
files, and also in the PatchApplier. In PatchApplier, also validate
paths.

Change-Id: Ie12864c54c9f901a2ccee7caddec73027f353111
Signed-off-by: Thomas Wolf <twolf@apache.org>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

2 files changed, 23 insertions, 26 deletions

diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/api/CheckoutCommand.java b/org.eclipse.jgit/src/org/eclipse/jgit/api/CheckoutCommand.java
index 7319ff4b2f..8edae5a580 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/api/CheckoutCommand.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/api/CheckoutCommand.java
@@ -1,6 +1,6 @@
 /*
  * Copyright (C) 2010, Chris Aniszczyk <caniszczyk@gmail.com>
- * Copyright (C) 2011, 2020 Matthias Sohn <matthias.sohn@sap.com> and others
+ * Copyright (C) 2011, 2023 Matthias Sohn <matthias.sohn@sap.com> and others
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Distribution License v. 1.0 which is available at
@@ -28,6 +28,7 @@ import org.eclipse.jgit.api.errors.InvalidRefNameException;
 import org.eclipse.jgit.api.errors.JGitInternalException;
 import org.eclipse.jgit.api.errors.RefAlreadyExistsException;
 import org.eclipse.jgit.api.errors.RefNotFoundException;
+import org.eclipse.jgit.dircache.Checkout;
 import org.eclipse.jgit.dircache.DirCache;
 import org.eclipse.jgit.dircache.DirCacheCheckout;
 import org.eclipse.jgit.dircache.DirCacheCheckout.CheckoutMetadata;
@@ -55,7 +56,6 @@ import org.eclipse.jgit.revwalk.RevCommit;
 import org.eclipse.jgit.revwalk.RevTree;
 import org.eclipse.jgit.revwalk.RevWalk;
 import org.eclipse.jgit.treewalk.TreeWalk;
-import org.eclipse.jgit.treewalk.WorkingTreeOptions;
 import org.eclipse.jgit.treewalk.filter.PathFilterGroup;
 
 /**
@@ -412,8 +412,7 @@ public class CheckoutCommand extends GitCommand<Ref> {
 	protected CheckoutCommand checkoutPaths() throws IOException,
 			RefNotFoundException {
 		actuallyModifiedPaths = new HashSet<>();
-		WorkingTreeOptions options = repo.getConfig()
-				.get(WorkingTreeOptions.KEY);
+		Checkout checkout = new Checkout(repo).setRecursiveDeletion(true);
 		DirCache dc = repo.lockDirCache();
 		try (RevWalk revWalk = new RevWalk(repo);
 				TreeWalk treeWalk = new TreeWalk(repo,
@@ -422,10 +421,10 @@ public class CheckoutCommand extends GitCommand<Ref> {
 			if (!checkoutAllPaths)
 				treeWalk.setFilter(PathFilterGroup.createFromStrings(paths));
 			if (isCheckoutIndex())
-				checkoutPathsFromIndex(treeWalk, dc, options);
+				checkoutPathsFromIndex(treeWalk, dc, checkout);
 			else {
 				RevCommit commit = revWalk.parseCommit(getStartPointObjectId());
-				checkoutPathsFromCommit(treeWalk, dc, commit, options);
+				checkoutPathsFromCommit(treeWalk, dc, commit, checkout);
 			}
 		} finally {
 			try {
@@ -443,7 +442,7 @@ public class CheckoutCommand extends GitCommand<Ref> {
 	}
 
 	private void checkoutPathsFromIndex(TreeWalk treeWalk, DirCache dc,
-			WorkingTreeOptions options)
+			Checkout checkout)
 			throws IOException {
 		DirCacheIterator dci = new DirCacheIterator(dc);
 		treeWalk.addTree(dci);
@@ -469,7 +468,7 @@ public class CheckoutCommand extends GitCommand<Ref> {
 					if (stage > DirCacheEntry.STAGE_0) {
 						if (checkoutStage != null) {
 							if (stage == checkoutStage.number) {
-								checkoutPath(ent, r, options,
+								checkoutPath(ent, r, checkout, path,
 										new CheckoutMetadata(eolStreamType,
 												filterCommand));
 								actuallyModifiedPaths.add(path);
@@ -480,7 +479,7 @@ public class CheckoutCommand extends GitCommand<Ref> {
 							throw new JGitInternalException(e.getMessage(), e);
 						}
 					} else {
-						checkoutPath(ent, r, options,
+						checkoutPath(ent, r, checkout, path,
 								new CheckoutMetadata(eolStreamType,
 										filterCommand));
 						actuallyModifiedPaths.add(path);
@@ -494,7 +493,7 @@ public class CheckoutCommand extends GitCommand<Ref> {
 	}
 
 	private void checkoutPathsFromCommit(TreeWalk treeWalk, DirCache dc,
-			RevCommit commit, WorkingTreeOptions options) throws IOException {
+			RevCommit commit, Checkout checkout) throws IOException {
 		treeWalk.addTree(commit.getTree());
 		final ObjectReader r = treeWalk.getObjectReader();
 		DirCacheEditor editor = dc.editor();
@@ -516,7 +515,7 @@ public class CheckoutCommand extends GitCommand<Ref> {
 					}
 					ent.setObjectId(blobId);
 					ent.setFileMode(mode);
-					checkoutPath(ent, r, options,
+					checkoutPath(ent, r, checkout, path,
 							new CheckoutMetadata(eolStreamType, filterCommand));
 					actuallyModifiedPaths.add(path);
 				}
@@ -526,10 +525,9 @@ public class CheckoutCommand extends GitCommand<Ref> {
 	}
 
 	private void checkoutPath(DirCacheEntry entry, ObjectReader reader,
-			WorkingTreeOptions options, CheckoutMetadata checkoutMetadata) {
+			Checkout checkout, String path, CheckoutMetadata checkoutMetadata) {
 		try {
-			DirCacheCheckout.checkoutEntry(repo, entry, reader, true,
-					checkoutMetadata, options);
+			checkout.checkout(entry, checkoutMetadata, reader, path);
 		} catch (IOException e) {
 			throw new JGitInternalException(MessageFormat.format(
 					JGitText.get().checkoutConflictWithFile,
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/api/StashApplyCommand.java b/org.eclipse.jgit/src/org/eclipse/jgit/api/StashApplyCommand.java
index 17036a9cd3..e4157286f1 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/api/StashApplyCommand.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/api/StashApplyCommand.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2012, 2021 GitHub Inc. and others
+ * Copyright (C) 2012, 2023 GitHub Inc. and others
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Distribution License v. 1.0 which is available at
@@ -23,6 +23,7 @@ import org.eclipse.jgit.api.errors.JGitInternalException;
 import org.eclipse.jgit.api.errors.NoHeadException;
 import org.eclipse.jgit.api.errors.StashApplyFailureException;
 import org.eclipse.jgit.api.errors.WrongRepositoryStateException;
+import org.eclipse.jgit.dircache.Checkout;
 import org.eclipse.jgit.dircache.DirCache;
 import org.eclipse.jgit.dircache.DirCacheBuilder;
 import org.eclipse.jgit.dircache.DirCacheCheckout;
@@ -48,7 +49,6 @@ import org.eclipse.jgit.revwalk.RevWalk;
 import org.eclipse.jgit.treewalk.AbstractTreeIterator;
 import org.eclipse.jgit.treewalk.FileTreeIterator;
 import org.eclipse.jgit.treewalk.TreeWalk;
-import org.eclipse.jgit.treewalk.WorkingTreeOptions;
 
 /**
  * Command class to apply a stashed commit.
@@ -383,8 +383,7 @@ public class StashApplyCommand extends GitCommand<ObjectId> {
 	private void resetUntracked(RevTree tree) throws CheckoutConflictException,
 			IOException {
 		Set<String> actuallyModifiedPaths = new HashSet<>();
-		WorkingTreeOptions options = repo.getConfig()
-				.get(WorkingTreeOptions.KEY);
+		Checkout checkout = new Checkout(repo).setRecursiveDeletion(true);
 		// TODO maybe NameConflictTreeWalk ?
 		try (TreeWalk walk = new TreeWalk(repo)) {
 			walk.addTree(tree);
@@ -408,17 +407,17 @@ public class StashApplyCommand extends GitCommand<ObjectId> {
 
 				FileTreeIterator fIter = walk
 						.getTree(1, FileTreeIterator.class);
+				String gitPath = entry.getPathString();
 				if (fIter != null) {
 					if (fIter.isModified(entry, true, reader)) {
 						// file exists and is dirty
-						throw new CheckoutConflictException(
-								entry.getPathString());
+						throw new CheckoutConflictException(gitPath);
 					}
 				}
 
-				checkoutPath(entry, reader, options,
+				checkoutPath(entry, gitPath, reader, checkout,
 						new CheckoutMetadata(eolStreamType, null));
-				actuallyModifiedPaths.add(entry.getPathString());
+				actuallyModifiedPaths.add(gitPath);
 			}
 		} finally {
 			if (!actuallyModifiedPaths.isEmpty()) {
@@ -428,11 +427,11 @@ public class StashApplyCommand extends GitCommand<ObjectId> {
 		}
 	}
 
-	private void checkoutPath(DirCacheEntry entry, ObjectReader reader,
-			WorkingTreeOptions options, CheckoutMetadata checkoutMetadata) {
+	private void checkoutPath(DirCacheEntry entry, String gitPath,
+			ObjectReader reader,
+			Checkout checkout, CheckoutMetadata checkoutMetadata) {
 		try {
-			DirCacheCheckout.checkoutEntry(repo, entry, reader, true,
-					checkoutMetadata, options);
+			checkout.checkout(entry, checkoutMetadata, reader, gitPath);
 		} catch (IOException e) {
 			throw new JGitInternalException(MessageFormat.format(
 					JGitText.get().checkoutConflictWithFile,