#23 Use filename@REV when using SVN 1.5

[Charles Lechasseur]

This patch detects SVN version in Subversion.pm and if using SVN 1.5, we use

svn cat filename@REV

instead of

svn cat --revision REV filename

This seems to work in all cases and there are cases where the latter doesn't work (particularly in cases where the file's path has been moved/deleted at some later point in the repository's lifetime).

[Charles Lechasseur]

Patch for Subversion.pm to enable filename@REV

[David Sitsky]

Logged In: YES
user_id=208928
Originator: NO

The semantics of using pegged vs operative revisions are actually a little bit different: http://svnbook.red-bean.com/en/1.1/ch07s03.html.

Pegged revisions have been around since 1.1 - 1.5 allowed them for svn:externals properties, but that doesn't affect us here.

To do this right - we really need to just support the user entering in pegged revisions directly into the start and end tag, and making the module argument optional.

This would allow people to create some pretty complicates diffs as a result.

[Charles Lechasseur]

Logged In: YES
user_id=2032979
Originator: YES

I see. But here, the fix is in the "retrieve" method, which is used to pull the content of a file for a specific revision, NOT in the method that generates the diff (which means that the revision passed to "retrieve" comes from the topicfile, not from the start_tag and end_tag entered by the user). In this case, using the pegged revision seems to make more sense. If we ask for the content of file@REV, without specifying an operative revision, we're basically asking for the latest version of file, looking at the given history line, which will return what we want.

Is there a case where "retrieve" would need to work on something other than a pegged revision?

[David Sitsky]

Logged In: YES
user_id=208928
Originator: NO

You probably right... just curious, can you tell me in your situation where not using the pegged version is causing issues with a specific example?

[Charles Lechasseur]

Logged In: YES
user_id=2032979
Originator: YES

We had a topic that pointed to an URL that was later moved in the repository. Trying to fetch the content of a file via "svn cat" with an operative revision gave out an error saying that the path was not found in a later revision. Using a pegged revision worked fine.

[David Sitsky]

Logged In: YES
user_id=208928
Originator: NO

That makes sense. Ok - I'll make sure this gets committed in - thanks for taking the time to explain this.

[David Sitsky]

Logged In: YES
user_id=208928
Originator: NO

I've committed this in. Since pegged versions have been available since Subversion 1.1, I haven't bothered with the version check.