Support relative submodule URLs on init/add/sync

Interpret submodule URLs that start with './' or '../' as
relative to either the configured remote for the HEAD branch,
or 'origin', or the parent repository working directory if no
remote URL is configured

Bug: 368536
Change-Id: Id4985824023b75cd45cd64a4dd9d421166391e10

6 files changed, 106 insertions, 4 deletions

diff --git a/org.eclipse.jgit/resources/org/eclipse/jgit/JGitText.properties b/org.eclipse.jgit/resources/org/eclipse/jgit/JGitText.properties
index a80e6bcae5..5b22801342 100644
--- a/org.eclipse.jgit/resources/org/eclipse/jgit/JGitText.properties
+++ b/org.eclipse.jgit/resources/org/eclipse/jgit/JGitText.properties
@@ -423,6 +423,7 @@ staleRevFlagsOn=Stale RevFlags on {0}
 startingReadStageWithoutWrittenRequestDataPendingIsNotSupported=Starting read stage without written request data pending is not supported
 statelessRPCRequiresOptionToBeEnabled=stateless RPC requires {0} to be enabled
 submoduleExists=Submodule ''{0}'' already exists in the index
+submoduleParentRemoteUrlInvalid=Cannot remove segment from remote url ''{0}''
 submodulesNotSupported=Submodules are not supported
 symlinkCannotBeWrittenAsTheLinkTarget=Symlink "{0}" cannot be written as the link target cannot be read from within Java.
 systemConfigFileInvalid=Systen wide config file {0} is invalid {1}
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/JGitText.java b/org.eclipse.jgit/src/org/eclipse/jgit/JGitText.java
index f4de487558..dbc3bcae62 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/JGitText.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/JGitText.java
@@ -484,6 +484,7 @@ public class JGitText extends TranslationBundle {
 	/***/ public String statelessRPCRequiresOptionToBeEnabled;
 	/***/ public String submoduleExists;
 	/***/ public String submodulesNotSupported;
+	/***/ public String submoduleParentRemoteUrlInvalid;
 	/***/ public String symlinkCannotBeWrittenAsTheLinkTarget;
 	/***/ public String systemConfigFileInvalid;
 	/***/ public String tagNameInvalid;
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/api/SubmoduleAddCommand.java b/org.eclipse.jgit/src/org/eclipse/jgit/api/SubmoduleAddCommand.java
index ac81ccb457..e1b293c43d 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/api/SubmoduleAddCommand.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/api/SubmoduleAddCommand.java
@@ -148,12 +148,18 @@ public class SubmoduleAddCommand extends
 			throw new JGitInternalException(e.getMessage(), e);
 		}
 
+		final String resolvedUri;
+		try {
+			resolvedUri = SubmoduleWalk.getSubmoduleRemoteUrl(repo, uri);
+		} catch (IOException e) {
+			throw new JGitInternalException(e.getMessage(), e);
+		}
 		// Clone submodule repository
 		File moduleDirectory = SubmoduleWalk.getSubmoduleDirectory(repo, path);
 		CloneCommand clone = Git.cloneRepository();
 		configure(clone);
 		clone.setDirectory(moduleDirectory);
-		clone.setURI(uri);
+		clone.setURI(resolvedUri);
 		if (monitor != null)
 			clone.setProgressMonitor(monitor);
 		Repository subRepo = clone.call().getRepository();
@@ -161,7 +167,7 @@ public class SubmoduleAddCommand extends
 		// Save submodule URL to parent repository's config
 		StoredConfig config = repo.getConfig();
 		config.setString(ConfigConstants.CONFIG_SUBMODULE_SECTION, path,
-				ConfigConstants.CONFIG_KEY_URL, uri);
+				ConfigConstants.CONFIG_KEY_URL, resolvedUri);
 		try {
 			config.save();
 		} catch (IOException e) {
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/api/SubmoduleInitCommand.java b/org.eclipse.jgit/src/org/eclipse/jgit/api/SubmoduleInitCommand.java
index ad8f02e47f..fef13704ef 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/api/SubmoduleInitCommand.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/api/SubmoduleInitCommand.java
@@ -106,7 +106,7 @@ public class SubmoduleInitCommand extends GitCommand<Collection<String>> {
 				String path = generator.getPath();
 				// Copy 'url' and 'update' fields from .gitmodules to config
 				// file
-				String url = generator.getModulesUrl();
+				String url = generator.getRemoteUrl();
 				String update = generator.getModulesUpdate();
 				if (url != null)
 					config.setString(ConfigConstants.CONFIG_SUBMODULE_SECTION,
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/api/SubmoduleSyncCommand.java b/org.eclipse.jgit/src/org/eclipse/jgit/api/SubmoduleSyncCommand.java
index 43647a0c69..fd8ddc941d 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/api/SubmoduleSyncCommand.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/api/SubmoduleSyncCommand.java
@@ -116,7 +116,7 @@ public class SubmoduleSyncCommand extends GitCommand<Map<String, String>> {
 			Map<String, String> synced = new HashMap<String, String>();
 			StoredConfig config = repo.getConfig();
 			while (generator.next()) {
-				String remoteUrl = generator.getModulesUrl();
+				String remoteUrl = generator.getRemoteUrl();
 				if (remoteUrl == null)
 					continue;
 
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/submodule/SubmoduleWalk.java b/org.eclipse.jgit/src/org/eclipse/jgit/submodule/SubmoduleWalk.java
index ebe994826e..78896f8a54 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/submodule/SubmoduleWalk.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/submodule/SubmoduleWalk.java
@@ -44,7 +44,9 @@ package org.eclipse.jgit.submodule;
 
 import java.io.File;
 import java.io.IOException;
+import java.text.MessageFormat;
 
+import org.eclipse.jgit.JGitText;
 import org.eclipse.jgit.dircache.DirCacheIterator;
 import org.eclipse.jgit.errors.ConfigInvalidException;
 import org.eclipse.jgit.errors.CorruptObjectException;
@@ -176,6 +178,83 @@ public class SubmoduleWalk {
 		return new File(getSubmoduleDirectory(parent, path), Constants.DOT_GIT);
 	}
 
+	/**
+	 * Resolve submodule repository URL.
+	 * <p>
+	 * This handles relative URLs that are typically specified in the
+	 * '.gitmodules' file by resolving them against the remote URL of the parent
+	 * repository.
+	 * <p>
+	 * Relative URLs will be resolved against the parent repository's working
+	 * directory if the parent repository has no configured remote URL.
+	 *
+	 * @param parent
+	 *            parent repository
+	 * @param url
+	 *            absolute or relative URL of the submodule repository
+	 * @return resolved URL
+	 * @throws IOException
+	 */
+	public static String getSubmoduleRemoteUrl(final Repository parent,
+			final String url) throws IOException {
+		if (!url.startsWith("./") && !url.startsWith("../"))
+			return url;
+
+		String remoteName = null;
+		// Look up remote URL associated wit HEAD ref
+		Ref ref = parent.getRef(Constants.HEAD);
+		if (ref != null) {
+			if (ref.isSymbolic())
+				ref = ref.getLeaf();
+			remoteName = parent.getConfig().getString(
+					ConfigConstants.CONFIG_BRANCH_SECTION,
+					Repository.shortenRefName(ref.getName()),
+					ConfigConstants.CONFIG_KEY_REMOTE);
+		}
+
+		// Fall back to 'origin' if current HEAD ref has no remote URL
+		if (remoteName == null)
+			remoteName = Constants.DEFAULT_REMOTE_NAME;
+
+		String remoteUrl = parent.getConfig().getString(
+				ConfigConstants.CONFIG_REMOTE_SECTION, remoteName,
+				ConfigConstants.CONFIG_KEY_URL);
+
+		// Fall back to parent repository's working directory if no remote URL
+		if (remoteUrl == null) {
+			remoteUrl = parent.getWorkTree().getAbsolutePath();
+			// Normalize slashes to '/'
+			if ('\\' == File.separatorChar)
+				remoteUrl = remoteUrl.replace('\\', '/');
+		}
+
+		// Remove trailing '/'
+		if (remoteUrl.charAt(remoteUrl.length() - 1) == '/')
+			remoteUrl = remoteUrl.substring(0, remoteUrl.length() - 1);
+
+		char separator = '/';
+		String submoduleUrl = url;
+		while (submoduleUrl.length() > 0) {
+			if (submoduleUrl.startsWith("./"))
+				submoduleUrl = submoduleUrl.substring(2);
+			else if (submoduleUrl.startsWith("../")) {
+				int lastSeparator = remoteUrl.lastIndexOf('/');
+				if (lastSeparator < 1) {
+					lastSeparator = remoteUrl.lastIndexOf(':');
+					separator = ':';
+				}
+				if (lastSeparator < 1)
+					throw new IOException(MessageFormat.format(
+							JGitText.get().submoduleParentRemoteUrlInvalid,
+							remoteUrl));
+				remoteUrl = remoteUrl.substring(0, lastSeparator);
+				submoduleUrl = submoduleUrl.substring(3);
+			} else
+				break;
+		}
+		return remoteUrl + separator + submoduleUrl;
+	}
+
 	private final Repository repository;
 
 	private final TreeWalk walk;
@@ -432,4 +511,19 @@ public class SubmoduleWalk {
 		Ref head = subRepo.getRef(Constants.HEAD);
 		return head != null ? head.getLeaf().getName() : null;
 	}
+
+	/**
+	 * Get the resolved remote URL for the current submodule.
+	 * <p>
+	 * This method resolves the value of {@link #getModulesUrl()} to an absolute
+	 * URL
+	 *
+	 * @return resolved remote URL
+	 * @throws IOException
+	 * @throws ConfigInvalidException
+	 */
+	public String getRemoteUrl() throws IOException, ConfigInvalidException {
+		String url = getModulesUrl();
+		return url != null ? getSubmoduleRemoteUrl(repository, url) : null;
+	}
 }