Merge branch 'jk/diff-convfilter-test-fix'

* jk/diff-convfilter-test-fix:
  Avoid using non-portable `echo -n` in tests.
  add userdiff textconv tests
  document the diff driver textconv feature
  diff: add missing static declaration

Conflicts:
	Documentation/gitattributes.txt

diff --cc Documentation/gitattributes.txt
index eb648418eedba4f131aec1f18ccba3bd62f53dc2,314e2d32e547308c12b28fe075e4c93aa2481533..a172baf993e5171932533ad713a5d0b34cb6850b
--- 1/Documentation/gitattributes.txt
--- 2/Documentation/gitattributes.txt
+++ b/Documentation/gitattributes.txt
@@@ -213,13 -213,12 +213,15 @@@ with `crlf`, and then `ident` and fed t
  Generating diff text
  ~~~~~~~~~~~~~~~~~~~~
  
- The attribute `diff` affects if 'git-diff' generates textual
- patch for the path or just says `Binary files differ`.  It also
- can affect what line is shown on the hunk header `@@ -k,l +n,m @@`
- line.
 +`diff`
 +^^^^^^
 +
+ The attribute `diff` affects how 'git' generates diffs for particular
+ files. It can tell git whether to generate a textual patch for the path
+ or to treat the path as a binary file.  It can also affect what line is
+ shown on the hunk header `@@ -k,l +n,m @@` line, tell git to use an
+ external command to generate the diff, or ask git to convert binary
+ files to a text format before generating the diff.
  
  Set::
  

diff --cc diff.c
Simple merge