Default for global (user) git ignore file

C git has a default for git config core.excludesfile: "Its default
value is $XDG_CONFIG_HOME/git/ignore. If $XDG_CONFIG_HOME is either
not set or empty, $HOME/.config/git/ignore is used instead." [1]

Implement this in the WorkingTreeIterator$RootIgnoreNode.

To make this testable, mock the "user.home" directory for all JGit
tests, otherwise tests might pick up a real user's git ignore file.
Also ensure that JGit code always reads "user.home" via the
SystemReader.

Add tests for both locations.

[1] https://git-scm.com/docs/gitignore#_description

Bug: 436127
Change-Id: Ie510259320286c3c13a6464a37da1bd9ca1e373a
Signed-off-by: Thomas Wolf <twolf@apache.org>

1 files changed, 19 insertions, 5 deletions

diff --git a/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/LocalDiskRepositoryTestCase.java b/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/LocalDiskRepositoryTestCase.java
index 0945327ab3..f816158b10 100644
--- a/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/LocalDiskRepositoryTestCase.java
+++ b/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/LocalDiskRepositoryTestCase.java
@@ -85,6 +85,8 @@ public abstract class LocalDiskRepositoryTestCase {
 	private final Set<Repository> toClose = new HashSet<>();
 	private File tmp;
 
+	private File homeDir;
+
 	/**
 	 * The current test name.
 	 *
@@ -119,6 +121,14 @@ public abstract class LocalDiskRepositoryTestCase {
 		mockSystemReader = new MockSystemReader();
 		SystemReader.setInstance(mockSystemReader);
 
+		// Mock the home directory. We don't want to pick up the real user's git
+		// config, or global git ignore.
+		// XDG_CONFIG_HOME isn't set in the MockSystemReader.
+		mockSystemReader.setProperty("user.home", tmp.getAbsolutePath());
+		mockSystemReader.setProperty("HOME", tmp.getAbsolutePath());
+		homeDir = FS.DETECTED.userHome();
+		FS.DETECTED.setUserHome(tmp.getAbsoluteFile());
+
 		// Measure timer resolution before the test to avoid time critical tests
 		// are affected by time needed for measurement.
 		// The MockSystemReader must be configured first since we need to use
@@ -195,21 +205,25 @@ public abstract class LocalDiskRepositoryTestCase {
 	@After
 	public void tearDown() throws Exception {
 		RepositoryCache.clear();
-		for (Repository r : toClose)
+		for (Repository r : toClose) {
 			r.close();
+		}
 		toClose.clear();
 
 		// Since memory mapping is controlled by the GC we need to
 		// tell it this is a good time to clean up and unlock
 		// memory mapped files.
 		//
-		if (useMMAP)
+		if (useMMAP) {
 			System.gc();
-		if (tmp != null)
+		}
+		FS.DETECTED.setUserHome(homeDir);
+		if (tmp != null) {
 			recursiveDelete(tmp, false, true);
-		if (tmp != null && !tmp.exists())
+		}
+		if (tmp != null && !tmp.exists()) {
 			CleanupThread.removed(tmp);
-
+		}
 		SystemReader.setInstance(null);
 	}