[PATCH v3 0/2] diff --no-index: support symlinks and pipes

[Dennis Kaarsemaker <dennis@kaarsemaker.net>]

git diff <(command1) <(command2) is less useful than it could be, all it outputs is:

diff --git a/dev/fd/63 b/dev/fd/62
index 9e6542b297..9f7b2c291b 120000
--- a/dev/fd/63
+++ b/dev/fd/62
@@ -1 +1 @@
-pipe:[464811685]
\ No newline at end of file
+pipe:[464811687]
\ No newline at end of file

Normal diff provides arguably better output: the diff of the output of the
commands. This series makes it possible for git diff --no-index to follow
symlinks and read from pipes, mimicking the behaviour of normal diff.

v1: http://public-inbox.org/git/20161111201958.2175-1-dennis@kaarsemaker.net/
v2: http://public-inbox.org/git/20170113102021.6054-1-dennis@kaarsemaker.net/

Changes since v2, prompted by feedback from Junio:

- A --derefence option was added and the default is no longer to dereference
  symlinks.
- Instead of looking at what canon_mode returns, use the original mode of 
  files to override behaviour for pipes.
- Turn the !S_ISREG(...) check into a should_mmap_file_contents helper.

Dennis Kaarsemaker (2):
  diff --no-index: optionally follow symlinks
  diff --no-index: support reading from pipes

 Documentation/diff-options.txt |  9 +++++++
 diff-no-index.c                | 16 ++++++++++---
 diff.c                         | 30 +++++++++++++++++++----
 diff.h                         |  2 +-
 t/t4053-diff-no-index.sh       | 54 ++++++++++++++++++++++++++++++++++++++++++
 t/test-lib.sh                  |  4 ++++
 6 files changed, 107 insertions(+), 8 deletions(-)

-- 
2.12.0-437-g0cc2799