Re: Misleading documentation for git-diff-files (diff-filter)
Thanks for the clarification! I also didn't realize that diff-files -R will show added files. You learn something new everyday ;) On Thu, Jan 4, 2018 at 11:09 AM, Junio C Hamano wrote: > Jeff King writes: > >> diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt >> index 9d1586b956..743af97b06 100644 >> --- a/Documentation/diff-options.txt >> +++ b/Documentation/diff-options.txt >> @@ -469,6 +469,12 @@ ifndef::git-format-patch[] >> + >> Also, these upper-case letters can be downcased to exclude. E.g. >> `--diff-filter=ad` excludes added and deleted paths. >> ++ >> +Note that not all diffs can feature all types. For instance, diffs >> +from the index to the working tree can never have Added entries >> +(because the set of paths included in the diff is limited by what is in >> +the index). Similarly, copied and renamed entries cannot appear if >> +detection for those types is disabled. > > Makes sense; thanks. -- --- John L Cheng
Re: Misleading documentation for git-diff-files (diff-filter)
Jeff King writes: > diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt > index 9d1586b956..743af97b06 100644 > --- a/Documentation/diff-options.txt > +++ b/Documentation/diff-options.txt > @@ -469,6 +469,12 @@ ifndef::git-format-patch[] > + > Also, these upper-case letters can be downcased to exclude. E.g. > `--diff-filter=ad` excludes added and deleted paths. > ++ > +Note that not all diffs can feature all types. For instance, diffs > +from the index to the working tree can never have Added entries > +(because the set of paths included in the diff is limited by what is in > +the index). Similarly, copied and renamed entries cannot appear if > +detection for those types is disabled. Makes sense; thanks.
Re: Misleading documentation for git-diff-files (diff-filter)
On Thu, Jan 04, 2018 at 07:53:53AM -0800, John Cheng wrote: > To be clear, I don't mean to imply that diff-files should include > files that are not the index. I was trying to say that as a user, the > documentation gave me a different impression. > > For background, my intent was to have a script to look for local git > repos that with unstaged changes. After some trial and error, I found > that git-ls-files gave me what I needed. However, I wanted to point > out why I initially believed git-diff-files with show "added files". I took your original mail to be a suggestion that the documentation could be more clear. :) So maybe something like the patch below? It actually would be an interesting feature for a diff from the index to the working tree to include untracked files as new entries. I don't think we'd want to do that by default (since the actions a user needs to take are quite different between a modified file, one marked intent-to-add, and an untracked one). But I could see it being useful for a caller to want to consider the whole tree as a single diff. -- >8 -- Subject: [PATCH] docs/diff-options: clarify scope of diff-filter types The same document for "--diff-filter" is included by many programs in the diff family. Because it mentions all possible types (added, removed, etc), this may imply to the reader that all types can be generated by a particular command. But this isn't necessarily the case; "diff-files" cannot generally produce an "Added" entry, since the diff is limited to what is already in the index. Let's make it clear that the list here is the full one, and does not imply anything about what a particular invocation may produce. Note that conditionally including items (e.g., omitting "Added" in the git-diff-files manpage) isn't the right solution here for two reasons: - The problem isn't diff-files, but doing an index to working tree diff. "git diff" can do the same diff, but also has other modes where "Added" does show up. - The direction of the diff matters. Doing "diff-files -R" can get you Added entries (but not Deleted ones). So it's best just to explain that the set of available types depends on the specific diff invocation. Reported-by: John Cheng Signed-off-by: Jeff King --- Documentation/diff-options.txt | 6 ++ 1 file changed, 6 insertions(+) diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt index 9d1586b956..743af97b06 100644 --- a/Documentation/diff-options.txt +++ b/Documentation/diff-options.txt @@ -469,6 +469,12 @@ ifndef::git-format-patch[] + Also, these upper-case letters can be downcased to exclude. E.g. `--diff-filter=ad` excludes added and deleted paths. ++ +Note that not all diffs can feature all types. For instance, diffs +from the index to the working tree can never have Added entries +(because the set of paths included in the diff is limited by what is in +the index). Similarly, copied and renamed entries cannot appear if +detection for those types is disabled. -S:: Look for differences that change the number of occurrences of -- 2.16.0.rc0.391.gbd38408415
Re: Misleading documentation for git-diff-files (diff-filter)
To be clear, I don't mean to imply that diff-files should include files that are not the index. I was trying to say that as a user, the documentation gave me a different impression. For background, my intent was to have a script to look for local git repos that with unstaged changes. After some trial and error, I found that git-ls-files gave me what I needed. However, I wanted to point out why I initially believed git-diff-files with show "added files". Think of this more as user feedback. On Wed, Jan 3, 2018 at 3:53 PM, Junio C Hamano wrote: > John Cheng writes: > >> I wanted to know if git diff-files shows files that are not in the >> index but are in the working tree. > > At least in the original design of Git, that would fundamentally be > impossible, as Git _only_ cares about paths that are in the index, > so a new file won't be in the picture until it is added. Because a > change is shown as "A"dded by the diff family of commands only when > the old side lacks a path that appears in the new side, there is no > way "diff-files" that compares the index and the working tree would > see a path that is missing from the old (i.e. the index) side. -- --- John L Cheng
Re: Misleading documentation for git-diff-files (diff-filter)
John Cheng writes: > I wanted to know if git diff-files shows files that are not in the > index but are in the working tree. At least in the original design of Git, that would fundamentally be impossible, as Git _only_ cares about paths that are in the index, so a new file won't be in the picture until it is added. Because a change is shown as "A"dded by the diff family of commands only when the old side lacks a path that appears in the new side, there is no way "diff-files" that compares the index and the working tree would see a path that is missing from the old (i.e. the index) side.
Misleading documentation for git-diff-files (diff-filter)
I originally asked this question on stackoverflow (https://stackoverflow.com/q/48039277). I wanted to know if git diff-files shows files that are not in the index but are in the working tree. The documentation says you can supply --diff-filter=A, which will select file "that are added". However, git-diff-files (appears) to never show any files with the status of "A". It seems like the cause is that git diff-files includes diff-options.txt which uses a standard template for --diff-filter which includes the "A" option. Perhaps a clarification can be added? Compares the files in the working tree and the index. When paths are specified, compares only those named paths. Otherwise all entries in the index are compared. The output format is the same as for 'git diff-index' and 'git diff-tree'. Files not in the index are not compared. -- --- John L Cheng