org.eclipse.jgit.blame.BlameGenerator Maven / Gradle / Ivy
/*
* Copyright (C) 2011, Google Inc.
* and other copyright owners as documented in the project's IP log.
*
* This program and the accompanying materials are made available
* under the terms of the Eclipse Distribution License v1.0 which
* accompanies this distribution, is reproduced below, and is
* available at http://www.eclipse.org/org/documents/edl-v10.php
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* - Neither the name of the Eclipse Foundation, Inc. nor the
* names of its contributors may be used to endorse or promote
* products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
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package org.eclipse.jgit.blame;
import static org.eclipse.jgit.lib.Constants.OBJ_BLOB;
import java.io.IOException;
import java.util.Collection;
import java.util.Collections;
import org.eclipse.jgit.blame.Candidate.BlobCandidate;
import org.eclipse.jgit.blame.Candidate.ReverseCandidate;
import org.eclipse.jgit.blame.ReverseWalk.ReverseCommit;
import org.eclipse.jgit.diff.DiffAlgorithm;
import org.eclipse.jgit.diff.DiffEntry;
import org.eclipse.jgit.diff.DiffEntry.ChangeType;
import org.eclipse.jgit.diff.EditList;
import org.eclipse.jgit.diff.HistogramDiff;
import org.eclipse.jgit.diff.RawText;
import org.eclipse.jgit.diff.RawTextComparator;
import org.eclipse.jgit.diff.RenameDetector;
import org.eclipse.jgit.internal.JGitText;
import org.eclipse.jgit.lib.AnyObjectId;
import org.eclipse.jgit.lib.MutableObjectId;
import org.eclipse.jgit.lib.ObjectId;
import org.eclipse.jgit.lib.ObjectLoader;
import org.eclipse.jgit.lib.ObjectReader;
import org.eclipse.jgit.lib.PersonIdent;
import org.eclipse.jgit.lib.Repository;
import org.eclipse.jgit.revwalk.RevCommit;
import org.eclipse.jgit.revwalk.RevFlag;
import org.eclipse.jgit.revwalk.RevWalk;
import org.eclipse.jgit.treewalk.TreeWalk;
import org.eclipse.jgit.treewalk.filter.PathFilter;
import org.eclipse.jgit.treewalk.filter.TreeFilter;
/**
* Generate author information for lines based on a provided file.
*
* Applications that want a simple one-shot computation of blame for a file
* should use {@link #computeBlameResult()} to prepare the entire result in one
* method call. This may block for significant time as the history of the
* repository must be traversed until information is gathered for every line.
*
* Applications that want more incremental update behavior may use either the
* raw {@link #next()} streaming approach supported by this class, or construct
* a {@link BlameResult} using {@link BlameResult#create(BlameGenerator)} and
* incrementally construct the result with {@link BlameResult#computeNext()}.
*
* This class is not thread-safe.
*
* An instance of BlameGenerator can only be used once. To blame multiple files
* the application must create a new BlameGenerator.
*
* During blame processing there are two files involved:
*
* - result - The file whose lines are being examined. This is the revision
* the user is trying to view blame/annotation information alongside of.
* - source - The file that was blamed with supplying one or more lines of
* data into result. The source may be a different file path (due to copy or
* rename). Source line numbers may differ from result line numbers due to lines
* being added/removed in intermediate revisions.
*
*
* The blame algorithm is implemented by initially assigning responsibility for
* all lines of the result to the starting commit. A difference against the
* commit's ancestor is computed, and responsibility is passed to the ancestor
* commit for any lines that are common. The starting commit is blamed only for
* the lines that do not appear in the ancestor, if any. The loop repeats using
* the ancestor, until there are no more lines to acquire information on, or the
* file's creation point is discovered in history.
*/
public class BlameGenerator {
private final Repository repository;
private final PathFilter resultPath;
private final MutableObjectId idBuf;
/** Revision pool used to acquire commits from. */
private RevWalk revPool;
/** Indicates the commit has already been processed. */
private RevFlag SEEN;
private ObjectReader reader;
private TreeWalk treeWalk;
private DiffAlgorithm diffAlgorithm = new HistogramDiff();
private RawTextComparator textComparator = RawTextComparator.DEFAULT;
private RenameDetector renameDetector;
/** Potential candidates, sorted by commit time descending. */
private Candidate queue;
/** Number of lines that still need to be discovered. */
private int remaining;
/** Blame is currently assigned to this source. */
private Candidate currentSource;
/**
* Create a blame generator for the repository and path (relative to
* repository)
*
* @param repository
* repository to access revision data from.
* @param path
* initial path of the file to start scanning (relative to the
* repository).
*/
public BlameGenerator(Repository repository, String path) {
this.repository = repository;
this.resultPath = PathFilter.create(path);
idBuf = new MutableObjectId();
setFollowFileRenames(true);
initRevPool(false);
remaining = -1;
}
private void initRevPool(boolean reverse) {
if (queue != null)
throw new IllegalStateException();
if (revPool != null)
revPool.release();
if (reverse)
revPool = new ReverseWalk(getRepository());
else
revPool = new RevWalk(getRepository());
revPool.setRetainBody(true);
SEEN = revPool.newFlag("SEEN"); //$NON-NLS-1$
reader = revPool.getObjectReader();
treeWalk = new TreeWalk(reader);
treeWalk.setRecursive(true);
}
/** @return repository being scanned for revision history. */
public Repository getRepository() {
return repository;
}
/** @return path file path being processed. */
public String getResultPath() {
return resultPath.getPath();
}
/**
* Difference algorithm to use when comparing revisions.
*
* @param algorithm
* @return {@code this}
*/
public BlameGenerator setDiffAlgorithm(DiffAlgorithm algorithm) {
diffAlgorithm = algorithm;
return this;
}
/**
* Text comparator to use when comparing revisions.
*
* @param comparator
* @return {@code this}
*/
public BlameGenerator setTextComparator(RawTextComparator comparator) {
textComparator = comparator;
return this;
}
/**
* Enable (or disable) following file renames, on by default.
*
* If true renames are followed using the standard FollowFilter behavior
* used by RevWalk (which matches {@code git log --follow} in the C
* implementation). This is not the same as copy/move detection as
* implemented by the C implementation's of {@code git blame -M -C}.
*
* @param follow
* enable following.
* @return {@code this}
*/
public BlameGenerator setFollowFileRenames(boolean follow) {
if (follow)
renameDetector = new RenameDetector(getRepository());
else
renameDetector = null;
return this;
}
/**
* Obtain the RenameDetector if {@code setFollowFileRenames(true)}.
*
* @return the rename detector, allowing the application to configure its
* settings for rename score and breaking behavior.
*/
public RenameDetector getRenameDetector() {
return renameDetector;
}
/**
* Push a candidate blob onto the generator's traversal stack.
*
* Candidates should be pushed in history order from oldest-to-newest.
* Applications should push the starting commit first, then the index
* revision (if the index is interesting), and finally the working tree
* copy (if the working tree is interesting).
*
* @param description
* description of the blob revision, such as "Working Tree".
* @param contents
* contents of the file.
* @return {@code this}
* @throws IOException
* the repository cannot be read.
*/
public BlameGenerator push(String description, byte[] contents)
throws IOException {
return push(description, new RawText(contents));
}
/**
* Push a candidate blob onto the generator's traversal stack.
*
* Candidates should be pushed in history order from oldest-to-newest.
* Applications should push the starting commit first, then the index
* revision (if the index is interesting), and finally the working tree copy
* (if the working tree is interesting).
*
* @param description
* description of the blob revision, such as "Working Tree".
* @param contents
* contents of the file.
* @return {@code this}
* @throws IOException
* the repository cannot be read.
*/
public BlameGenerator push(String description, RawText contents)
throws IOException {
if (description == null)
description = JGitText.get().blameNotCommittedYet;
BlobCandidate c = new BlobCandidate(description, resultPath);
c.sourceText = contents;
c.regionList = new Region(0, 0, contents.size());
remaining = contents.size();
push(c);
return this;
}
/**
* Push a candidate object onto the generator's traversal stack.
*
* Candidates should be pushed in history order from oldest-to-newest.
* Applications should push the starting commit first, then the index
* revision (if the index is interesting), and finally the working tree copy
* (if the working tree is interesting).
*
* @param description
* description of the blob revision, such as "Working Tree".
* @param id
* may be a commit or a blob.
* @return {@code this}
* @throws IOException
* the repository cannot be read.
*/
public BlameGenerator push(String description, AnyObjectId id)
throws IOException {
ObjectLoader ldr = reader.open(id);
if (ldr.getType() == OBJ_BLOB) {
if (description == null)
description = JGitText.get().blameNotCommittedYet;
BlobCandidate c = new BlobCandidate(description, resultPath);
c.sourceBlob = id.toObjectId();
c.sourceText = new RawText(ldr.getCachedBytes(Integer.MAX_VALUE));
c.regionList = new Region(0, 0, c.sourceText.size());
remaining = c.sourceText.size();
push(c);
return this;
}
RevCommit commit = revPool.parseCommit(id);
if (!find(commit, resultPath))
return this;
Candidate c = new Candidate(commit, resultPath);
c.sourceBlob = idBuf.toObjectId();
c.loadText(reader);
c.regionList = new Region(0, 0, c.sourceText.size());
remaining = c.sourceText.size();
push(c);
return this;
}
/**
* Configure the generator to compute reverse blame (history of deletes).
*
* This method is expensive as it immediately runs a RevWalk over the
* history spanning the expression {@code start..end} (end being more recent
* than start) and then performs the equivalent operation as
* {@link #push(String, AnyObjectId)} to begin blame traversal from the
* commit named by {@code start} walking forwards through history until
* {@code end} blaming line deletions.
*
* A reverse blame may produce multiple sources for the same result line,
* each of these is a descendant commit that removed the line, typically
* this occurs when the same deletion appears in multiple side branches such
* as due to a cherry-pick. Applications relying on reverse should use
* {@link BlameResult} as it filters these duplicate sources and only
* remembers the first (oldest) deletion.
*
* @param start
* oldest commit to traverse from. The result file will be loaded
* from this commit's tree.
* @param end
* most recent commit to stop traversal at. Usually an active
* branch tip, tag, or HEAD.
* @return {@code this}
* @throws IOException
* the repository cannot be read.
*/
public BlameGenerator reverse(AnyObjectId start, AnyObjectId end)
throws IOException {
return reverse(start, Collections.singleton(end.toObjectId()));
}
/**
* Configure the generator to compute reverse blame (history of deletes).
*
* This method is expensive as it immediately runs a RevWalk over the
* history spanning the expression {@code start..end} (end being more recent
* than start) and then performs the equivalent operation as
* {@link #push(String, AnyObjectId)} to begin blame traversal from the
* commit named by {@code start} walking forwards through history until
* {@code end} blaming line deletions.
*
* A reverse blame may produce multiple sources for the same result line,
* each of these is a descendant commit that removed the line, typically
* this occurs when the same deletion appears in multiple side branches such
* as due to a cherry-pick. Applications relying on reverse should use
* {@link BlameResult} as it filters these duplicate sources and only
* remembers the first (oldest) deletion.
*
* @param start
* oldest commit to traverse from. The result file will be loaded
* from this commit's tree.
* @param end
* most recent commits to stop traversal at. Usually an active
* branch tip, tag, or HEAD.
* @return {@code this}
* @throws IOException
* the repository cannot be read.
*/
public BlameGenerator reverse(AnyObjectId start,
Collection end) throws IOException {
initRevPool(true);
ReverseCommit result = (ReverseCommit) revPool.parseCommit(start);
if (!find(result, resultPath))
return this;
revPool.markUninteresting(result);
for (ObjectId id : end)
revPool.markStart(revPool.parseCommit(id));
while (revPool.next() != null) {
// just pump the queue
}
ReverseCandidate c = new ReverseCandidate(result, resultPath);
c.sourceBlob = idBuf.toObjectId();
c.loadText(reader);
c.regionList = new Region(0, 0, c.sourceText.size());
remaining = c.sourceText.size();
push(c);
return this;
}
/**
* Execute the generator in a blocking fashion until all data is ready.
*
* @return the complete result. Null if no file exists for the given path.
* @throws IOException
* the repository cannot be read.
*/
public BlameResult computeBlameResult() throws IOException {
try {
BlameResult r = BlameResult.create(this);
if (r != null)
r.computeAll();
return r;
} finally {
release();
}
}
/**
* Step the blame algorithm one iteration.
*
* @return true if the generator has found a region's source. The getSource*
* and {@link #getResultStart()}, {@link #getResultEnd()} methods
* can be used to inspect the region found. False if there are no
* more regions to describe.
* @throws IOException
* repository cannot be read.
*/
public boolean next() throws IOException {
// If there is a source still pending, produce the next region.
if (currentSource != null) {
Region r = currentSource.regionList;
Region n = r.next;
remaining -= r.length;
if (n != null) {
currentSource.regionList = n;
return true;
}
if (currentSource.queueNext != null)
return result(currentSource.queueNext);
currentSource = null;
}
// If there are no lines remaining, the entire result is done,
// even if there are revisions still available for the path.
if (remaining == 0)
return done();
for (;;) {
Candidate n = pop();
if (n == null)
return done();
int pCnt = n.getParentCount();
if (pCnt == 1) {
if (processOne(n))
return true;
} else if (1 < pCnt) {
if (processMerge(n))
return true;
} else if (n instanceof ReverseCandidate) {
// Do not generate a tip of a reverse. The region
// survives and should not appear to be deleted.
} else /* if (pCnt == 0) */{
// Root commit, with at least one surviving region.
// Assign the remaining blame here.
return result(n);
}
}
}
private boolean done() {
release();
return false;
}
private boolean result(Candidate n) throws IOException {
if (n.sourceCommit != null)
revPool.parseBody(n.sourceCommit);
currentSource = n;
return true;
}
private boolean reverseResult(Candidate parent, Candidate source)
throws IOException {
// On a reverse blame present the application the parent
// (as this is what did the removals), however the region
// list to enumerate is the source's surviving list.
Candidate res = parent.copy(parent.sourceCommit);
res.regionList = source.regionList;
return result(res);
}
private Candidate pop() {
Candidate n = queue;
if (n != null) {
queue = n.queueNext;
n.queueNext = null;
}
return n;
}
private void push(BlobCandidate toInsert) {
Candidate c = queue;
if (c != null) {
c.regionList = null;
toInsert.parent = c;
}
queue = toInsert;
}
private void push(Candidate toInsert) {
// Mark sources to ensure they get discarded (above) if
// another path to the same commit.
toInsert.add(SEEN);
// Insert into the queue using descending commit time, so
// the most recent commit will pop next.
int time = toInsert.getTime();
Candidate n = queue;
if (n == null || time >= n.getTime()) {
toInsert.queueNext = n;
queue = toInsert;
return;
}
for (Candidate p = n;; p = n) {
n = p.queueNext;
if (n == null || time >= n.getTime()) {
toInsert.queueNext = n;
p.queueNext = toInsert;
return;
}
}
}
private boolean processOne(Candidate n) throws IOException {
RevCommit parent = n.getParent(0);
if (parent == null)
return split(n.getNextCandidate(0), n);
if (parent.has(SEEN))
return false;
revPool.parseHeaders(parent);
if (find(parent, n.sourcePath)) {
if (idBuf.equals(n.sourceBlob)) {
// The common case of the file not being modified in
// a simple string-of-pearls history. Blame parent.
n.sourceCommit = parent;
push(n);
return false;
}
Candidate next = n.create(parent, n.sourcePath);
next.sourceBlob = idBuf.toObjectId();
next.loadText(reader);
return split(next, n);
}
if (n.sourceCommit == null)
return result(n);
DiffEntry r = findRename(parent, n.sourceCommit, n.sourcePath);
if (r == null)
return result(n);
if (0 == r.getOldId().prefixCompare(n.sourceBlob)) {
// A 100% rename without any content change can also
// skip directly to the parent.
n.sourceCommit = parent;
n.sourcePath = PathFilter.create(r.getOldPath());
push(n);
return false;
}
Candidate next = n.create(parent, PathFilter.create(r.getOldPath()));
next.sourceBlob = r.getOldId().toObjectId();
next.renameScore = r.getScore();
next.loadText(reader);
return split(next, n);
}
private boolean split(Candidate parent, Candidate source)
throws IOException {
EditList editList = diffAlgorithm.diff(textComparator,
parent.sourceText, source.sourceText);
if (editList.isEmpty()) {
// Ignoring whitespace (or some other special comparator) can
// cause non-identical blobs to have an empty edit list. In
// a case like this push the parent alone.
parent.regionList = source.regionList;
push(parent);
return false;
}
parent.takeBlame(editList, source);
if (parent.regionList != null)
push(parent);
if (source.regionList != null) {
if (source instanceof ReverseCandidate)
return reverseResult(parent, source);
return result(source);
}
return false;
}
private boolean processMerge(Candidate n) throws IOException {
int pCnt = n.getParentCount();
for (int pIdx = 0; pIdx < pCnt; pIdx++) {
RevCommit parent = n.getParent(pIdx);
if (parent.has(SEEN))
continue;
revPool.parseHeaders(parent);
}
// If any single parent exactly matches the merge, follow only
// that one parent through history.
ObjectId[] ids = null;
for (int pIdx = 0; pIdx < pCnt; pIdx++) {
RevCommit parent = n.getParent(pIdx);
if (parent.has(SEEN))
continue;
if (!find(parent, n.sourcePath))
continue;
if (!(n instanceof ReverseCandidate) && idBuf.equals(n.sourceBlob)) {
n.sourceCommit = parent;
push(n);
return false;
}
if (ids == null)
ids = new ObjectId[pCnt];
ids[pIdx] = idBuf.toObjectId();
}
// If rename detection is enabled, search for any relevant names.
DiffEntry[] renames = null;
if (renameDetector != null) {
renames = new DiffEntry[pCnt];
for (int pIdx = 0; pIdx < pCnt; pIdx++) {
RevCommit parent = n.getParent(pIdx);
if (parent.has(SEEN))
continue;
if (ids != null && ids[pIdx] != null)
continue;
DiffEntry r = findRename(parent, n.sourceCommit, n.sourcePath);
if (r == null)
continue;
if (n instanceof ReverseCandidate) {
if (ids == null)
ids = new ObjectId[pCnt];
ids[pCnt] = r.getOldId().toObjectId();
} else if (0 == r.getOldId().prefixCompare(n.sourceBlob)) {
// A 100% rename without any content change can also
// skip directly to the parent. Note this bypasses an
// earlier parent that had the path (above) but did not
// have an exact content match. For performance reasons
// we choose to follow the one parent over trying to do
// possibly both parents.
n.sourceCommit = parent;
n.sourcePath = PathFilter.create(r.getOldPath());
push(n);
return false;
}
renames[pIdx] = r;
}
}
// Construct the candidate for each parent.
Candidate[] parents = new Candidate[pCnt];
for (int pIdx = 0; pIdx < pCnt; pIdx++) {
RevCommit parent = n.getParent(pIdx);
if (parent.has(SEEN))
continue;
Candidate p;
if (renames != null && renames[pIdx] != null) {
p = n.create(parent,
PathFilter.create(renames[pIdx].getOldPath()));
p.renameScore = renames[pIdx].getScore();
p.sourceBlob = renames[pIdx].getOldId().toObjectId();
} else if (ids != null && ids[pIdx] != null) {
p = n.create(parent, n.sourcePath);
p.sourceBlob = ids[pIdx];
} else {
continue;
}
EditList editList;
if (n instanceof ReverseCandidate
&& p.sourceBlob.equals(n.sourceBlob)) {
// This special case happens on ReverseCandidate forks.
p.sourceText = n.sourceText;
editList = new EditList(0);
} else {
p.loadText(reader);
editList = diffAlgorithm.diff(textComparator,
p.sourceText, n.sourceText);
}
if (editList.isEmpty()) {
// Ignoring whitespace (or some other special comparator) can
// cause non-identical blobs to have an empty edit list. In
// a case like this push the parent alone.
if (n instanceof ReverseCandidate) {
parents[pIdx] = p;
continue;
}
p.regionList = n.regionList;
push(p);
return false;
}
p.takeBlame(editList, n);
// Only remember this parent candidate if there is at least
// one region that was blamed on the parent.
if (p.regionList != null) {
// Reverse blame requires inverting the regions. This puts
// the regions the parent deleted from us into the parent,
// and retains the common regions to look at other parents
// for deletions.
if (n instanceof ReverseCandidate) {
Region r = p.regionList;
p.regionList = n.regionList;
n.regionList = r;
}
parents[pIdx] = p;
}
}
if (n instanceof ReverseCandidate) {
// On a reverse blame report all deletions found in the children,
// and pass on to them a copy of our region list.
Candidate resultHead = null;
Candidate resultTail = null;
for (int pIdx = 0; pIdx < pCnt; pIdx++) {
Candidate p = parents[pIdx];
if (p == null)
continue;
if (p.regionList != null) {
Candidate r = p.copy(p.sourceCommit);
if (resultTail != null) {
resultTail.queueNext = r;
resultTail = r;
} else {
resultHead = r;
resultTail = r;
}
}
if (n.regionList != null) {
p.regionList = n.regionList.deepCopy();
push(p);
}
}
if (resultHead != null)
return result(resultHead);
return false;
}
// Push any parents that are still candidates.
for (int pIdx = 0; pIdx < pCnt; pIdx++) {
if (parents[pIdx] != null)
push(parents[pIdx]);
}
if (n.regionList != null)
return result(n);
return false;
}
/**
* Get the revision blamed for the current region.
*
* The source commit may be null if the line was blamed to an uncommitted
* revision, such as the working tree copy, or during a reverse blame if the
* line survives to the end revision (e.g. the branch tip).
*
* @return current revision being blamed.
*/
public RevCommit getSourceCommit() {
return currentSource.sourceCommit;
}
/** @return current author being blamed. */
public PersonIdent getSourceAuthor() {
return currentSource.getAuthor();
}
/** @return current committer being blamed. */
public PersonIdent getSourceCommitter() {
RevCommit c = getSourceCommit();
return c != null ? c.getCommitterIdent() : null;
}
/** @return path of the file being blamed. */
public String getSourcePath() {
return currentSource.sourcePath.getPath();
}
/** @return rename score if a rename occurred in {@link #getSourceCommit}. */
public int getRenameScore() {
return currentSource.renameScore;
}
/**
* @return first line of the source data that has been blamed for the
* current region. This is line number of where the region was added
* during {@link #getSourceCommit()} in file
* {@link #getSourcePath()}.
*/
public int getSourceStart() {
return currentSource.regionList.sourceStart;
}
/**
* @return one past the range of the source data that has been blamed for
* the current region. This is line number of where the region was
* added during {@link #getSourceCommit()} in file
* {@link #getSourcePath()}.
*/
public int getSourceEnd() {
Region r = currentSource.regionList;
return r.sourceStart + r.length;
}
/**
* @return first line of the result that {@link #getSourceCommit()} has been
* blamed for providing. Line numbers use 0 based indexing.
*/
public int getResultStart() {
return currentSource.regionList.resultStart;
}
/**
* @return one past the range of the result that {@link #getSourceCommit()}
* has been blamed for providing. Line numbers use 0 based indexing.
* Because a source cannot be blamed for an empty region of the
* result, {@link #getResultEnd()} is always at least one larger
* than {@link #getResultStart()}.
*/
public int getResultEnd() {
Region r = currentSource.regionList;
return r.resultStart + r.length;
}
/**
* @return number of lines in the current region being blamed to
* {@link #getSourceCommit()}. This is always the value of the
* expression {@code getResultEnd() - getResultStart()}, but also
* {@code getSourceEnd() - getSourceStart()}.
*/
public int getRegionLength() {
return currentSource.regionList.length;
}
/**
* @return complete contents of the source file blamed for the current
* output region. This is the contents of {@link #getSourcePath()}
* within {@link #getSourceCommit()}. The source contents is
* temporarily available as an artifact of the blame algorithm. Most
* applications will want the result contents for display to users.
*/
public RawText getSourceContents() {
return currentSource.sourceText;
}
/**
* @return complete file contents of the result file blame is annotating.
* This value is accessible only after being configured and only
* immediately before the first call to {@link #next()}. Returns
* null if the path does not exist.
* @throws IOException
* repository cannot be read.
* @throws IllegalStateException
* {@link #next()} has already been invoked.
*/
public RawText getResultContents() throws IOException {
return queue != null ? queue.sourceText : null;
}
/** Release the current blame session. */
public void release() {
revPool.release();
queue = null;
currentSource = null;
}
private boolean find(RevCommit commit, PathFilter path) throws IOException {
treeWalk.setFilter(path);
treeWalk.reset(commit.getTree());
while (treeWalk.next()) {
if (path.isDone(treeWalk)) {
if (treeWalk.getFileMode(0).getObjectType() != OBJ_BLOB)
return false;
treeWalk.getObjectId(idBuf, 0);
return true;
}
if (treeWalk.isSubtree())
treeWalk.enterSubtree();
}
return false;
}
private DiffEntry findRename(RevCommit parent, RevCommit commit,
PathFilter path) throws IOException {
if (renameDetector == null)
return null;
treeWalk.setFilter(TreeFilter.ANY_DIFF);
treeWalk.reset(parent.getTree(), commit.getTree());
renameDetector.reset();
renameDetector.addAll(DiffEntry.scan(treeWalk));
for (DiffEntry ent : renameDetector.compute()) {
if (isRename(ent) && ent.getNewPath().equals(path.getPath()))
return ent;
}
return null;
}
private static boolean isRename(DiffEntry ent) {
return ent.getChangeType() == ChangeType.RENAME
|| ent.getChangeType() == ChangeType.COPY;
}
}