com.diffplug.spotless.extra

Class GitRatchet<Project>

java.lang.Object

com.diffplug.spotless.extra.GitRatchet<Project>

All Implemented Interfaces:

AutoCloseable

public abstract class GitRatchet<Project>
extends Object
implements AutoCloseable

How to use:

• For best performance, you should have one instance of GitRatchet, shared by all projects.
• Use rootTreeShaOf(Object, String) to turn origin/master into the SHA of the tree object at that reference
• Use isClean(Object, ObjectId, File) to see if the given file is “git clean” relative to that tree
• If you have up-to-date checking and want the best possible performance, use subtreeShaOf(Object, ObjectId) to optimize up-to-date checks on a per-project basis.

Constructor Summary

Constructors

Constructor and Description
GitRatchet()

Method Summary

Modifier and Type	Method and Description
void	close()
protected abstract File	getDir(Project project)
protected abstract Project	getParent(Project project)
boolean	isClean(Project project, org.eclipse.jgit.lib.ObjectId treeSha, File file)
boolean	isClean(Project project, org.eclipse.jgit.lib.ObjectId treeSha, String relativePathUnix) This is the highest-level method, which all the others serve.
protected org.eclipse.jgit.lib.Repository	repositoryFor(Project project) The first part of making this fast is finding the appropriate git repository quickly.
org.eclipse.jgit.lib.ObjectId	rootTreeShaOf(Project project, String reference) Fast way to return treeSha of the given ref against the git repository which stores the given project.
org.eclipse.jgit.lib.ObjectId	subtreeShaOf(Project project, org.eclipse.jgit.lib.ObjectId rootTreeSha) Returns the sha of the git subtree which represents the root of the given project, or ObjectId.zeroId() if there is no git subtree at the project root.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

GitRatchet

public GitRatchet()

Method Detail

isClean

public boolean isClean(Project project,
                       org.eclipse.jgit.lib.ObjectId treeSha,
                       File file)
                throws IOException

Throws:

IOException

isClean

public boolean isClean(Project project,
                       org.eclipse.jgit.lib.ObjectId treeSha,
                       String relativePathUnix)
                throws IOException

This is the highest-level method, which all the others serve. Given the sha of a git tree (not a commit!), and the file in question, this method returns true if that file is clean relative to that tree. A naive implementation of this could be verrrry slow, so the rest of this is about speeding this up.

Throws:

IOException

repositoryFor

protected org.eclipse.jgit.lib.Repository repositoryFor(Project project)
                                                 throws IOException

The first part of making this fast is finding the appropriate git repository quickly. Because of composite builds and submodules, it’s quite possible that a single Gradle project will span across multiple git repositories. We cache the Repository for every Project in gitRoots, and use dynamic programming to populate it.

Throws:

IOException

getDir

protected abstract File getDir(Project project)

getParent

@Nullable
protected abstract Project getParent(Project project)

rootTreeShaOf

public org.eclipse.jgit.lib.ObjectId rootTreeShaOf(Project project,
                                                   String reference)

Fast way to return treeSha of the given ref against the git repository which stores the given project. Because of parallel project evaluation, there may be races here, so we synchronize on ourselves. However, this method is the only method which can trigger any changes, and it is only called during project evaluation. That means our state is final/read-only during task execution, so we don’t need any locks during the heavy lifting.

subtreeShaOf

public org.eclipse.jgit.lib.ObjectId subtreeShaOf(Project project,
                                                  org.eclipse.jgit.lib.ObjectId rootTreeSha)

Returns the sha of the git subtree which represents the root of the given project, or ObjectId.zeroId() if there is no git subtree at the project root.

close

public void close()

Specified by:

close in interface AutoCloseable