Add support for git config repack.packKeptObjects

Change Ide3445e652 introduced the `--pack-kept-objects` option to GC for
including the objects contained in the locked packfiles during the
repack phase.

Whilst this allowed to explicitly pass a command line argument to the
jgit gc program, it did not allow the option to be read from
configuration.

Allow the pack kept objects option to be configured exactly as C-Git
documents [1], by introducing a new `repack.packKeptObjects`
configuration.

`repack.packKeptObjects` defaults to `true`, when the
`pack.buildBitmaps` is `true` (which is the default case), `false`
otherwise.

[1] https://git-scm.com/docs/git-config#Documentation/git-config.txt-repackpackKeptObjects

Bug: 582292
Change-Id: Ia931667277410d71bc079d27c097a57094299840

7 files changed, 191 insertions, 17 deletions

diff --git a/Documentation/config-options.md b/Documentation/config-options.md
index 5d76483acf..7221cceb35 100644
--- a/Documentation/config-options.md
+++ b/Documentation/config-options.md
@@ -110,3 +110,9 @@ Proxy configuration uses the standard Java mechanisms via class `java.net.ProxyS
 | `pack.waitPreventRacyPack` | `false` | ⃞ | Whether we wait before opening a newly written pack to prevent its lastModified timestamp could be racy. |
 | `pack.window` | `10` | ✅ | Number of objects to try when looking for a delta base per thread searching for deltas. |
 | `pack.windowMemory` | `0` (unlimited) | ✅ | Maximum number of bytes to put into the delta search window. |
+
+## __repack__ options
+
+|  option | default | git option | description |
+|---------|---------|------------|-------------|
+| `repack.packKeptObjects` | `true` when `pack.buildBitmaps` is set, `false` otherwise | ✅ | Include objects in packs locked by a `.keep` file when repacking. |
\ No newline at end of file
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/GcKeepFilesTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/GcKeepFilesTest.java
index 5919192e54..074728b680 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/GcKeepFilesTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/GcKeepFilesTest.java
@@ -10,6 +10,10 @@
 
 package org.eclipse.jgit.internal.storage.file;
 
+import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_BUILD_BITMAPS;
+import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_PACK_KEPT_OBJECTS;
+import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_PACK_SECTION;
+import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_REPACK_SECTION;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotNull;
@@ -20,7 +24,9 @@ import java.util.Iterator;
 import org.eclipse.jgit.internal.storage.file.PackIndex.MutableEntry;
 import org.eclipse.jgit.internal.storage.pack.PackExt;
 import org.eclipse.jgit.junit.TestRepository.BranchBuilder;
+import org.eclipse.jgit.lib.Config;
 import org.eclipse.jgit.lib.ObjectId;
+import org.eclipse.jgit.storage.pack.PackConfig;
 import org.junit.Test;
 
 public class GcKeepFilesTest extends GcTestCase {
@@ -55,6 +61,7 @@ public class GcKeepFilesTest extends GcTestCase {
 		PackFile bitmapFile = singlePack.getPackFile().create(PackExt.BITMAP_INDEX);
 		assertTrue(keepFile.exists());
 		assertTrue(bitmapFile.delete());
+		gc.setPackKeptObjects(false);
 		gc.gc();
 		stats = gc.getStatistics();
 		assertEquals(0, stats.numberOfLooseObjects);
@@ -78,17 +85,91 @@ public class GcKeepFilesTest extends GcTestCase {
 	}
 
 	@Test
-	public void testKeptObjectsAreIncluded() throws Exception {
+	public void testKeptObjectsAreIncludedByDefault() throws Exception {
+		testKeptObjectsAreIncluded();
+	}
+
+	@Test
+	public void testKeptObjectsAreIncludedByDefaultWhenBuildBitmapsIsTrue()
+			throws Exception {
+		PackConfig packConfig = new PackConfig();
+		Config repoConfig = repo.getObjectDatabase().getConfig();
+		repoConfig.setBoolean(CONFIG_PACK_SECTION, null,
+				CONFIG_KEY_BUILD_BITMAPS, true);
+		packConfig.fromConfig(repoConfig);
+		gc.setPackConfig(packConfig);
+
+		testKeptObjectsAreIncluded();
+	}
+
+	@Test
+	public void testKeptObjectsAreIncludedWhenPackKeptObjectsIsFalseButOverriddenViaCommandLine()
+			throws Exception {
+		PackConfig packConfig = new PackConfig();
+		packConfig.setPackKeptObjects(false);
+		gc.setPackConfig(packConfig);
+		gc.setPackKeptObjects(true);
+
+		testKeptObjectsAreIncluded();
+	}
+
+	@Test
+	public void testKeptObjectsAreNotIncludedByDefaultWhenBuildBitmapsIsFalse()
+			throws Exception {
+		PackConfig packConfig = new PackConfig();
+		packConfig.setBuildBitmaps(false);
+		gc.setPackConfig(packConfig);
+
+		testKeptObjectsAreNotIncluded();
+	}
+
+	@Test
+	public void testKeptObjectsAreIncludedWhenBuildBitmapsIsFalseButPackKeptObjectsIsTrue()
+			throws Exception {
+		PackConfig packConfig = new PackConfig();
+		Config repoConfig = repo.getObjectDatabase().getConfig();
+		repoConfig.setBoolean(CONFIG_PACK_SECTION, null,
+				CONFIG_KEY_BUILD_BITMAPS, false);
+		repoConfig.setBoolean(CONFIG_REPACK_SECTION, null,
+				CONFIG_KEY_PACK_KEPT_OBJECTS, true);
+		packConfig.fromConfig(repoConfig);
+		gc.setPackConfig(packConfig);
+
+		testKeptObjectsAreIncluded();
+	}
+
+	@Test
+	public void testKeptObjectsAreNotIncludedWhenPackKeptObjectsIsTrueButOverriddenViaCommandLine()
+			throws Exception {
+		PackConfig packConfig = new PackConfig();
+		packConfig.setPackKeptObjects(true);
+		gc.setPackConfig(packConfig);
+		gc.setPackKeptObjects(false);
+
+		testKeptObjectsAreNotIncluded();
+	}
+
+	@Test
+	public void testKeptObjectsAreNotIncludedWhenPackKeptObjectsConfigIsFalse()
+			throws Exception {
+		PackConfig packConfig = new PackConfig();
+		packConfig.setPackKeptObjects(false);
+		gc.setPackConfig(packConfig);
+
+		testKeptObjectsAreNotIncluded();
+	}
+
+	private void testKeptObjectsAreIncluded() throws Exception {
 		BranchBuilder bb = tr.branch("refs/heads/master");
 		ObjectId commitObjectInLockedPack = bb.commit().create().toObjectId();
 		gc.gc();
 		stats = gc.getStatistics();
 		assertEquals(COMMIT_AND_TREE_OBJECTS, stats.numberOfPackedObjects);
 		assertEquals(1, stats.numberOfPackFiles);
-		assertTrue(getSinglePack().getPackFile().create(PackExt.KEEP).createNewFile());
+		assertTrue(getSinglePack().getPackFile().create(PackExt.KEEP)
+				.createNewFile());
 
 		bb.commit().create();
-		gc.setPackKeptObjects(true);
 		gc.gc();
 		stats = gc.getStatistics();
 		assertEquals(2 * COMMIT_AND_TREE_OBJECTS + 1,
@@ -110,15 +191,15 @@ public class GcKeepFilesTest extends GcTestCase {
 		assertTrue(newPackIdx.hasObject(commitObjectInLockedPack));
 	}
 
-	@Test
-	public void testKeptObjectsAreNotIncludedByDefault() throws Exception {
+	private void testKeptObjectsAreNotIncluded() throws Exception {
 		BranchBuilder bb = tr.branch("refs/heads/master");
 		ObjectId commitObjectInLockedPack = bb.commit().create().toObjectId();
 		gc.gc();
 		stats = gc.getStatistics();
 		assertEquals(COMMIT_AND_TREE_OBJECTS, stats.numberOfPackedObjects);
 		assertEquals(1, stats.numberOfPackFiles);
-		assertTrue(getSinglePack().getPackFile().create(PackExt.KEEP).createNewFile());
+		assertTrue(getSinglePack().getPackFile().create(PackExt.KEEP)
+				.createNewFile());
 
 		bb.commit().create();
 		gc.gc();
@@ -142,8 +223,7 @@ public class GcKeepFilesTest extends GcTestCase {
 	}
 
 	private Pack getSinglePack() {
-		Iterator<Pack> packIt = repo.getObjectDatabase().getPacks()
-				.iterator();
+		Iterator<Pack> packIt = repo.getObjectDatabase().getPacks().iterator();
 		Pack singlePack = packIt.next();
 		assertFalse(packIt.hasNext());
 		return singlePack;
diff --git a/org.eclipse.jgit/.settings/.api_filters b/org.eclipse.jgit/.settings/.api_filters
index 24c6a3150f..caf331143b 100644
--- a/org.eclipse.jgit/.settings/.api_filters
+++ b/org.eclipse.jgit/.settings/.api_filters
@@ -53,6 +53,18 @@
                 <message_argument value="SHA1_IMPLEMENTATION"/>
             </message_arguments>
         </filter>
+        <filter id="1142947843">
+            <message_arguments>
+                <message_argument value="5.13.3"/>
+                <message_argument value="CONFIG_KEY_PACK_KEPT_OBJECTS"/>
+            </message_arguments>
+        </filter>
+        <filter id="1142947843">
+            <message_arguments>
+                <message_argument value="5.13.3"/>
+                <message_argument value="CONFIG_REPACK_SECTION"/>
+            </message_arguments>
+        </filter>
     </resource>
     <resource path="src/org/eclipse/jgit/lib/Repository.java" type="org.eclipse.jgit.lib.Repository">
         <filter id="1142947843">
@@ -72,6 +84,12 @@
         <filter id="336658481">
             <message_arguments>
                 <message_argument value="org.eclipse.jgit.storage.pack.PackConfig"/>
+                <message_argument value="DEFAULT_PACK_KEPT_OBJECTS"/>
+            </message_arguments>
+        </filter>
+        <filter id="336658481">
+            <message_arguments>
+                <message_argument value="org.eclipse.jgit.storage.pack.PackConfig"/>
                 <message_argument value="DEFAULT_SEARCH_FOR_REUSE_TIMEOUT"/>
             </message_arguments>
         </filter>
@@ -93,6 +111,12 @@
                 <message_argument value="setBitmapExcludedRefsPrefixes(String[])"/>
             </message_arguments>
         </filter>
+        <filter id="1142947843">
+            <message_arguments>
+                <message_argument value="5.13.3"/>
+                <message_argument value="DEFAULT_PACK_KEPT_OBJECTS"/>
+            </message_arguments>
+        </filter>
     </resource>
     <resource path="src/org/eclipse/jgit/transport/BasePackPushConnection.java" type="org.eclipse.jgit.transport.BasePackPushConnection">
         <filter id="338792546">
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/api/GarbageCollectCommand.java b/org.eclipse.jgit/src/org/eclipse/jgit/api/GarbageCollectCommand.java
index 2e09d4a8e3..8b7e3e161f 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/api/GarbageCollectCommand.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/api/GarbageCollectCommand.java
@@ -62,7 +62,7 @@ public class GarbageCollectCommand extends GitCommand<Properties> {
 
 	private PackConfig pconfig;
 
-	private boolean packKeptObjects;
+	private Boolean packKeptObjects;
 
 	/**
 	 * Constructor for GarbageCollectCommand.
@@ -141,7 +141,7 @@ public class GarbageCollectCommand extends GitCommand<Properties> {
 	 * @since 5.13.3
 	 */
 	public GarbageCollectCommand setPackKeptObjects(boolean packKeptObjects) {
-		this.packKeptObjects = packKeptObjects;
+		this.packKeptObjects = Boolean.valueOf(packKeptObjects);
 		return this;
 	}
 
@@ -189,8 +189,9 @@ public class GarbageCollectCommand extends GitCommand<Properties> {
 				gc.setProgressMonitor(monitor);
 				if (this.expire != null)
 					gc.setExpire(expire);
-				gc.setPackKeptObjects(packKeptObjects);
-
+				if (this.packKeptObjects != null) {
+					gc.setPackKeptObjects(packKeptObjects.booleanValue());
+				}
 				try {
 					gc.gc();
 					return toProperties(gc.getStatistics());
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/GC.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/GC.java
index 63edfa64b9..c8dd71ca33 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/GC.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/GC.java
@@ -158,7 +158,7 @@ public class GC {
 
 	private Date packExpire;
 
-	private boolean packKeptObjects;
+	private Boolean packKeptObjects;
 
 	private PackConfig pconfig;
 
@@ -841,7 +841,7 @@ public class GC {
 		List<ObjectIdSet> excluded = new LinkedList<>();
 		for (Pack p : repo.getObjectDatabase().getPacks()) {
 			checkCancelled();
-			if (!packKeptObjects && p.shouldBeKept()) {
+			if (!shouldPackKeptObjects() && p.shouldBeKept()) {
 				excluded.add(p.getIndex());
 			}
 		}
@@ -1316,7 +1316,13 @@ public class GC {
 	 * @param packKeptObjects Whether to include objects in `.keep` files when repacking.
 	 */
 	public void setPackKeptObjects(boolean packKeptObjects) {
-		this.packKeptObjects = packKeptObjects;
+		this.packKeptObjects = Boolean.valueOf(packKeptObjects);
+	}
+
+	@SuppressWarnings("boxing")
+	private boolean shouldPackKeptObjects() {
+		return Optional.ofNullable(packKeptObjects)
+				.orElse(pconfig.isPackKeptObjects());
 	}
 
 	/**
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/lib/ConfigConstants.java b/org.eclipse.jgit/src/org/eclipse/jgit/lib/ConfigConstants.java
index 634e3f7f86..605b44bee8 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/lib/ConfigConstants.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/lib/ConfigConstants.java
@@ -59,6 +59,12 @@ public final class ConfigConstants {
 	/** The "gc" section */
 	public static final String CONFIG_GC_SECTION = "gc";
 
+	/**
+	 * The "repack" section
+	 * @since 5.13.3
+	 */
+	public static final String CONFIG_REPACK_SECTION = "repack";
+
 	/** The "pack" section */
 	public static final String CONFIG_PACK_SECTION = "pack";
 
@@ -729,6 +735,13 @@ public final class ConfigConstants {
 	public static final String CONFIG_KEY_WINDOW_MEMORY = "windowmemory";
 
 	/**
+	 * The "repack.packKeptObjects" key
+	 *
+	 * @since 5.13.3
+	 */
+	public static final String CONFIG_KEY_PACK_KEPT_OBJECTS = "packkeptobjects";
+
+	/**
 	 * The "feature" section
 	 *
 	 * @since 5.9
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/storage/pack/PackConfig.java b/org.eclipse.jgit/src/org/eclipse/jgit/storage/pack/PackConfig.java
index 163e475887..47ea733faf 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/storage/pack/PackConfig.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/storage/pack/PackConfig.java
@@ -37,8 +37,10 @@ import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_WAIT_PREVENT_RACYP
 import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_WINDOW;
 import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_WINDOW_MEMORY;
 import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_PACK_SECTION;
+import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_PACK_KEPT_OBJECTS;
 import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_PRESERVE_OLD_PACKS;
 import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_PRUNE_PRESERVED;
+import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_REPACK_SECTION;
 
 import java.time.Duration;
 import java.util.concurrent.Executor;
@@ -168,6 +170,16 @@ public class PackConfig {
 	 */
 	public static final boolean DEFAULT_BUILD_BITMAPS = true;
 
+
+	/**
+	 * Default value for including objects in packs locked by .keep file when
+	 * repacking: {@value}
+	 *
+	 * @see #setPackKeptObjects(boolean)
+	 * @since 5.13.3
+	 */
+	public static final boolean DEFAULT_PACK_KEPT_OBJECTS = false;
+
 	/**
 	 * Default count of most recent commits to select for bitmaps. Only applies
 	 * when bitmaps are enabled: {@value}
@@ -284,6 +296,8 @@ public class PackConfig {
 
 	private boolean buildBitmaps = DEFAULT_BUILD_BITMAPS;
 
+	private boolean packKeptObjects = DEFAULT_PACK_KEPT_OBJECTS;
+
 	private int bitmapContiguousCommitCount = DEFAULT_BITMAP_CONTIGUOUS_COMMIT_COUNT;
 
 	private int bitmapRecentCommitCount = DEFAULT_BITMAP_RECENT_COMMIT_COUNT;
@@ -362,6 +376,7 @@ public class PackConfig {
 		this.executor = cfg.executor;
 		this.indexVersion = cfg.indexVersion;
 		this.buildBitmaps = cfg.buildBitmaps;
+		this.packKeptObjects = cfg.packKeptObjects;
 		this.bitmapContiguousCommitCount = cfg.bitmapContiguousCommitCount;
 		this.bitmapRecentCommitCount = cfg.bitmapRecentCommitCount;
 		this.bitmapRecentCommitSpan = cfg.bitmapRecentCommitSpan;
@@ -990,6 +1005,31 @@ public class PackConfig {
 	}
 
 	/**
+	 * Set whether to include objects in `.keep` files when repacking.
+	 *
+	 * <p>Default setting: {@value #DEFAULT_PACK_KEPT_OBJECTS}
+	 *
+	 * @param packKeptObjects boolean indicating whether to include objects in
+	 *     `.keep` files when repacking.
+	 * @since 5.13
+	 */
+	public void setPackKeptObjects(boolean packKeptObjects) {
+		this.packKeptObjects = packKeptObjects;
+	}
+
+	/**
+	 * True if objects in `.keep` files should be included when repacking.
+	 *
+	 * Default setting: {@value #DEFAULT_PACK_KEPT_OBJECTS}
+	 *
+	 * @return True if objects in `.keep` files should be included when repacking.
+	 * @since 5.13
+	 */
+	public boolean isPackKeptObjects() {
+		return packKeptObjects;
+	}
+
+	/**
 	 * Get the count of most recent commits for which to build bitmaps.
 	 *
 	 * Default setting: {@value #DEFAULT_BITMAP_CONTIGUOUS_COMMIT_COUNT}
@@ -1234,8 +1274,12 @@ public class PackConfig {
 		setSinglePack(rc.getBoolean(CONFIG_PACK_SECTION,
 				CONFIG_KEY_SINGLE_PACK,
 				getSinglePack()));
-		setBuildBitmaps(rc.getBoolean(CONFIG_PACK_SECTION,
-				CONFIG_KEY_BUILD_BITMAPS, isBuildBitmaps()));
+		boolean buildBitmapsFromConfig = rc.getBoolean(CONFIG_PACK_SECTION,
+				CONFIG_KEY_BUILD_BITMAPS, isBuildBitmaps());
+		setBuildBitmaps(buildBitmapsFromConfig);
+		setPackKeptObjects(rc.getBoolean(CONFIG_REPACK_SECTION,
+				CONFIG_KEY_PACK_KEPT_OBJECTS,
+				buildBitmapsFromConfig || isPackKeptObjects()));
 		setBitmapContiguousCommitCount(rc.getInt(CONFIG_PACK_SECTION,
 				CONFIG_KEY_BITMAP_CONTIGUOUS_COMMIT_COUNT,
 				getBitmapContiguousCommitCount()));