svn diff URL URL won't work when URLs are files

The svn will produce a bogus diff when targets are urls to file. 
 
### start of script 
 
svnadmin create repo 
svn mkdir -m '' file://`pwd`/repo/trunk 
svn mkdir -m '' file://`pwd`/repo/tags 
svn co  file://`pwd`/repo/trunk repo-wc 
 
cat <<EOF > repo-wc/f.txt 
foo 
bar 
snafu 
EOF 
 
svn add repo-wc/f.txt 
svn ci -m '' repo-wc/f.txt 
svn cp -m '' repo-wc/f.txt file://`pwd`/repo/tags/f-1.txt 
 
# 'edit' the file, remove a line, add fews 
cat <<EOF > repo-wc/f.txt 
foo 
snafu 
abcdefgh 
opqrstuw 
EOF 
 
svn ci -m '' repo-wc/f.txt 
svn cp -m '' repo-wc/f.txt file://`pwd`/repo/tags/f-2.txt 
 
svn diff file://`pwd`/repo/tags/f-1.txt file://`pwd`/repo/tags/f-2.txt 
 
svn co  file://`pwd`/repo/tags repo-tags 
diff -u repo-tags/f-1.txt repo-tags/f-2.txt 
 
### end of script 
 
The result will be: 
### svn diff file://`pwd`/repo/tags/f-1.txtfile://`pwd`/repo/tags/f-2.txt 
Index: f-2.txt 
=================================================================== 
--- f-2.txt (.../1.txt) (revision 6) 
+++ f-2.txt (.../2.txt) (revision 6) 
@@ -1,4 +1,4 @@ 
 foo 
-snafu 
-abcdefgh 
+u 
+abcdabcdefgh 
 opqrstuw 
 
 
When it should be something like: 
### diff -u repo-tags/f-1.txt repo-tags/f-2.txt 
--- repo-tags/f-1.txt   2003-05-12 17:22:53.000000000 +0300 
+++ repo-tags/f-2.txt   2003-05-12 17:22:53.000000000 +0300 
@@ -1,3 +1,4 @@ 
 foo 
-bar 
 snafu 
+abcdefgh 
+opqrstuw 
 
On 12 May 2003, Philip Martin wrote: 
 
> I get the same result using HEAD.  If I reverse the order of the 
> arguments I get 
> 
> $ svn diff file://`pwd`/repo/tags/f-2.txt file://`pwd`/repo/tags/f-1.txt 
> ../svn/subversion/libsvn_delta/text_delta.c:461: (apr_err=200003) 
> svn: Incomplete data 
> svn: Delta source ended unexpectedly 
> 
> I suspect the delta is being applied to the wrong source.

http://www.contactor.se/~dast/svn/archive-2003-07/1041.shtml

Original issue reported by jaa