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Bug 354919

Summary:

DiffFormatter#format(List<DiffEntry>) fails unless #scan(ATI, ATI) is called first

Product:

[Technology] JGit

Reporter:

Tomasz Zarna <tomasz.zarna>

Component:

JGit

Assignee:

Robin Rosenberg <robin.rosenberg>

Status:

RESOLVED FIXED

QA Contact:

Severity:

normal

Priority:

CC:

caniszczyk, christian.halstrick, Szymon.Brandys

Version:

1.1

Target Milestone:

---

Hardware:

OS:

All

URL:

http://egit.eclipse.org/r/4036

Whiteboard:

Bug Depends on:

Bug Blocks:

338205

Attachments:

Description	Flags
mylyn/context/zip	none

Description Tomasz Zarna

2011-08-17 05:09:17 EDT

With bug 334766 fixed I wanted to start using the new command by taking the returned list of DiffEntries and passing it to DiffFormatter#format(List <? extends DiffEntry>)[1]. To my surprise, in some cases it failed with a MissingObjectException. After a quick investigation it turned out that DiffFormatter#format(List<DiffEntry>) cannot be used if #scan(AbstractTreeIterator, AbstractTreeIterator)[2] hasn't been called first. The reason for this is simple, the #scan method updates the pair of sources used access the old and new sides of a DiffEntry[3]. It doesn't happen if you create a DiffFormatter from the scratch, init it properly and then try to call the #format(List<DiffEntry>) method with a list returned by the DiffCommand.

I can think of two solutions here:
* fix the formatter so the #format method can be called in isolation
* hide the method and enhance the DiffCommand so it returns formatted diffs

[1] org.eclipse.jgit.diff.DiffFormatter.format(List<? extends DiffEntry>)
[2] org.eclipse.jgit.diff.DiffFormatter.scan(AbstractTreeIterator, AbstractTreeIterator)
[1] org.eclipse.jgit.diff.DiffFormatter.source

Comment 1 Tomasz Zarna

2011-08-18 07:29:56 EDT

Created attachment 201707 [details]
mylyn/context/zip

Comment 2 Tomasz Zarna

2011-08-18 07:47:33 EDT

Implemented a third solution here: http://egit.eclipse.org/r/4036. The DiffCommand now accepts OutputStream to write line data, so DiffFormat#format(List<DiffEntry>) is no longer called in the command explicitly. The method has been also annotated with a warning that #scan should be called first.

Comment 3 Szymon Brandys

2011-11-03 06:41:59 EDT

Ping.

Comment 4 Tomasz Zarna

2011-12-27 09:24:30 EST

This has been fixed with acd8aee98ac851b0c091bc5c5ea53cb2eaabbad0 Available in JGit 1.3