Some Eclipse Foundation services are deprecated, or will be soon. Please ensure you've read this important communication.

Bug 322732

Summary:	NPE when opening compare editor from first changeset in synchronize view
Product:	[Technology] EGit	Reporter:	Matthias Sohn <matthias.sohn>
Component:	UI	Assignee:	Dariusz Luksza <dariusz.luksza>
Status:	RESOLVED FIXED	QA Contact:
Severity:	major
Priority:	P3	CC:	caniszczyk, dariusz.luksza, remy.suen, stefan.lay
Version:	unspecified
Target Milestone:	0.9.0-M2
Hardware:	PC
OS:	Mac OS X - Carbon (unsup.)
Whiteboard:
Bug Depends on:	322935
Bug Blocks:

Description Matthias Sohn

2010-08-15 18:57:37 EDT

egit version: 562b88498
jgit version: 8d761febc

eclipse.buildId=I20100608-0911
java.version=1.6.0_20
java.vendor=Apple Inc.
BootLoader constants: OS=macosx, ARCH=x86_64, WS=cocoa, NL=en_US
Framework arguments:  -product org.eclipse.platform.ide
Command-line arguments:  -product org.eclipse.platform.ide -data /Users/d029788/Documents/workspace/egit/../runtime-New_configuration -dev file:/Users/d029788/Documents/workspace/egit/.metadata/.plugins/org.eclipse.pde.core/EGit/dev.properties -os macosx -ws cocoa -arch x86_64 -consoleLog

- clone jgit
- change one jgit source file and commit the change
- Team > Synchronize
- the changeset containing this change is shown properly
- drill down to file which has been changed in Synchronize view
- double click on the changed file in Synchronize view
- NPE is thrown
- do another change and repeat the sequence on this change -> no NPE is thrown

Error
Mon Aug 16 00:43:00 CEST 2010
An internal error occurred during: "Initializing Compare Editor".

java.lang.NullPointerException
	at org.eclipse.jgit.util.RawParseUtils.author(RawParseUtils.java:549)
	at org.eclipse.jgit.revwalk.RevCommit.getAuthorIdent(RevCommit.java:303)
	at org.eclipse.egit.core.internal.storage.CommitFileRevision.<init>(CommitFileRevision.java:59)
	at org.eclipse.egit.core.internal.storage.GitFileRevision.inCommit(GitFileRevision.java:50)
	at org.eclipse.egit.ui.internal.CompareUtils.getFileRevision(CompareUtils.java:110)
	at org.eclipse.egit.ui.internal.CompareUtils.getFileRevisionTypedElement(CompareUtils.java:73)
	at org.eclipse.egit.ui.internal.synchronize.model.GitModelBlob.getRight(GitModelBlob.java:114)
	at org.eclipse.egit.ui.internal.synchronize.model.GitModelBlob.prepareInput(GitModelBlob.java:141)
	at org.eclipse.team.internal.ui.mapping.ModelCompareEditorInput.prepareCompareInput(ModelCompareEditorInput.java:121)
	at org.eclipse.team.ui.synchronize.SaveableCompareEditorInput.prepareInput(SaveableCompareEditorInput.java:235)
	at org.eclipse.compare.CompareEditorInput.run(CompareEditorInput.java:483)
	at org.eclipse.compare.internal.CompareUIPlugin.prepareInput(CompareUIPlugin.java:548)
	at org.eclipse.compare.internal.CompareEditor$2.run(CompareEditor.java:349)
	at org.eclipse.core.internal.jobs.Worker.run(Worker.java:54)

Comment 1 Dariusz Luksza

2010-08-17 03:32:01 EDT

I've investigate it and it appears that this NPE occurs for all files that are associated with oldest commit that is included in change set.

Comment 2 Chris Aniszczyk

2010-08-17 11:58:47 EDT

*** Bug 322920 has been marked as a duplicate of this bug. ***

Comment 3 Dariusz Luksza

2010-08-17 12:33:12 EDT

From my point of view this look like a bug in JGit. For some strange reasons JGit lost some data in RevCommit object. From my investigations appears that sometime:
revCommit.getParrent(0).getAuthorIdent()
throws NPE but calling:
revCommit.getParrent(0).getId()
on same object return commit SHA-1

Quick fix for this seems to be re-parsing revCommit object, so I've add this to GitCommiModel constructor. Check does all baseCommit's has author indent and it appears to be working ... but while calling Compare View NPE still occur. Even that all baseCommit's was re-parsed in GitModelObject constructor.

Finally, the true quick fix for this would be replacing simple getBaseCommit() in GitModelBlob.getRight() with RevWalk.parseCommit(getBaseCommit()). With this approach NPE doesn't occur any more but this is rather workaround then true fix.

Comment 4 Chris Aniszczyk

2010-08-17 12:35:03 EDT

(In reply to comment #3)
> From my point of view this look like a bug in JGit. For some strange reasons
> JGit lost some data in RevCommit object. From my investigations appears that
> sometime:
> revCommit.getParrent(0).getAuthorIdent()
> throws NPE but calling:
> revCommit.getParrent(0).getId()
> on same object return commit SHA-1
> 
> Quick fix for this seems to be re-parsing revCommit object, so I've add this to
> GitCommiModel constructor. Check does all baseCommit's has author indent and it
> appears to be working ... but while calling Compare View NPE still occur. Even
> that all baseCommit's was re-parsed in GitModelObject constructor.
> 
> Finally, the true quick fix for this would be replacing simple getBaseCommit()
> in GitModelBlob.getRight() with RevWalk.parseCommit(getBaseCommit()). With this
> approach NPE doesn't occur any more but this is rather workaround then true
> fix.

Send an email to jgit-dev and file a bug against JGit.

Comment 5 Dariusz Luksza

2010-08-19 10:29:11 EDT

This patch should fix this:

http://egit.eclipse.org/r/1339

Comment 6 Chris Aniszczyk

2010-08-19 10:35:58 EDT

Fixed with ff88637c69af6e114c3d8c722681f655943dfe23

Thanks Dariusz!

Comment 7 Remy Suen

2010-08-20 15:59:36 EDT

*** Bug 322498 has been marked as a duplicate of this bug. ***