We already talk about how to use each one and how they work, but it is a reasonable question to wonder why one might use one over the other. Signed-off-by: Jeff King <peff@xxxxxxxx> --- This can probably go with Jay's --textconv documentation topic. Documentation/gitattributes.txt | 31 +++++++++++++++++++++++++++++++ 1 files changed, 31 insertions(+), 0 deletions(-) diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt index 15aebc6..412c55b 100644 --- a/Documentation/gitattributes.txt +++ b/Documentation/gitattributes.txt @@ -593,6 +593,37 @@ and now produces better output), you can remove the cache manually with `git update-ref -d refs/notes/textconv/jpg` (where "jpg" is the name of the diff driver, as in the example above). +Choosing textconv versus external diff +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +If you want to show differences between binary or specially-formatted +blobs in your repository, you can choose to use either an external diff +command, or to use textconv to convert them to a diff-able text format. +Which method you choose depends on your exact situation. + +The advantage of using an external diff command is flexibility. You are +not bound to find line-oriented changes, nor is it necessary for the +output to resemble unified diff. You are free to locate and report +changes in the most appropriate way for your data format. + +A textconv, by comparison, is much more limiting. You provide a +transformation of the data into a line-oriented text format, and git +uses its regular diff tools to generate the output. There are several +advantages to choosing this method: + +1. Ease of use. It is often much simpler to write a binary to text + transformation than it is to perform your own diff. In many cases, + existing programs can be used as textconv filters (e.g., exif, + odt2txt). + +2. Git diff features. By performing only the transformation step + yourself, you can still utilize many of git's diff features, + including colorization, word-diff, and combined diffs for merges. + +3. Caching. Textconv caching can speed up repeated diffs, such as those + you might trigger by running `git log -p`. + + Marking files as binary ^^^^^^^^^^^^^^^^^^^^^^^ -- 1.7.4.5.7.g2e01 -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html