How to diff changes from a stable version in CLAM

Since the change of SVN for CVS in Clam (a year ago aprox) we do not explicitly tag the releases and that’s fine because SVN revision numbers are global. On the other hand, SVN do can create tags but it is dangerous because a tag is exactly the same thing as a branch. So SVN doesn’t prevent to commit to a tag.

Our tagging approach is very simple and proved useful: just write the revision number of each release in the CHANGES files. This simplifies the release process and also the way to make diffs –since you always use the same syntax.

Now an example: Let’s say we want to see changes in SMSTranspose files from last stable release (1.1.0):

1) Look for the svn revision corresponding to a stable version in the CHANGES file


NetworkEditor$ head CHANGES

2007-??-?? NetworkEditor 1.1.1 SVN $Revision: 10220 $
''
*

2007-06-08 NetworkEditor 1.1.0
'More eye-candy, please'
* SVN Revision: 10216
* Using CLAM 1.1.0
* New examples
* genderChange: fully working now and with an interface


So version 1.1.0 is revision 10216.
By the way, you maybe are curious on this $Revision: 10220 $ part of the first line. This is a SVN variable (or pattern). Each time you commit this CHANGE file the number gets updated to the current revision. That means that we actually never write the revision numbers in CHANGES files, we only have to remove the “$” when we decide to tag the release.

2) Now diff the files of interest on that version and head


NetworkEditor$ svn diff -r 10216:HEAD src/processing/SMSTranspose.*xx
Index: src/processing/SMSTranspose.cxx
===================================================================
--- src/processing/SMSTranspose.cxx (revision 10216)
+++ src/processing/SMSTranspose.cxx (revision 10281)
@@ -20,11 +20,15 @@
*/
#include "SMSTranspose.hxx"
-#include
+#include
#include
...


Last, a quick tip for the gvim users: pipe the diff result to gvim using -R – options:
$ svn diff | gvim -R -
And take advantage of vim syntax highlighting and quick navigation.