On Fri, Apr 14, 2023 at 10:58 AM Philippe Blain via GitGitGadget <gitgitgadget@xxxxxxxxx> wrote: > > From: Philippe Blain <levraiphilippeblain@xxxxxxxxx> > > Since 5291828df8 (merge-ort: write $GIT_DIR/AUTO_MERGE whenever we hit a > conflict, 2021-03-20), when using the 'ort' merge strategy, the special > ref AUTO_MERGE is written when a merge operation results in conflicts. > This ref points to a tree recording the conflicted state of the working > tree and is very useful during conflict resolution. However, this ref is > not documented. > > Add some documentation for AUTO_MERGE in git-diff(1), git-merge(1), > gitrevisions(7) and in the user manual. > > In git-diff(1), mention it at the end of the description section, when > we mention that the command also accepts trees instead of commits, and > also add an invocation to the "Various ways to check your working tree" > example. > > In git-merge(1), add a step to the list of things that happen "when it > is not obvious how to reconcile the changes", under the "True merge" > secion. Also mention AUTO_MERGE in the "How to resolve conflicts" s/secion/section/ > section, when mentioning 'git diff'. > > In gitrevisions(7), add a mention of AUTO_MERGE along with the other > special refs. > > In the user manual, add a paragraph describing AUTO_MERGE to the > "Getting conflict-resolution help during a merge" section, and include > an example of a 'git diff AUTO_MERGE' invocation for the example > conflict used in that section. Note that for uniformity we do not use > backticks around AUTO_MERGE here since the rest of the document does not > typeset special refs differently. > > Closes: https://github.com/gitgitgadget/git/issues/1471 > Signed-off-by: Philippe Blain <levraiphilippeblain@xxxxxxxxx> > --- > Documentation/git-diff.txt | 8 +++++++- > Documentation/git-merge.txt | 9 +++++++-- > Documentation/revisions.txt | 6 +++++- > Documentation/user-manual.txt | 27 +++++++++++++++++++++++++++ > 4 files changed, 46 insertions(+), 4 deletions(-) > > diff --git a/Documentation/git-diff.txt b/Documentation/git-diff.txt > index 52b679256c4..a85cc756ebc 100644 > --- a/Documentation/git-diff.txt > +++ b/Documentation/git-diff.txt > @@ -102,7 +102,11 @@ If --merge-base is given, use the merge base of the two commits for the > Just in case you are doing something exotic, it should be > noted that all of the <commit> in the above description, except > in the `--merge-base` case and in the last two forms that use `..` > -notations, can be any <tree>. > +notations, can be any <tree>. A tree of interest is the one pointed to > +by the special ref `AUTO_MERGE`, which is written by the 'ort' merge > +strategy upon hitting merge conflicts (see linkgit:git-merge[1]). > +Comparing the working tree with `AUTO_MERGE` shows changes you've made > +so far to resolve conflicts (see the examples below). > > For a more complete list of ways to spell <commit>, see > "SPECIFYING REVISIONS" section in linkgit:gitrevisions[7]. > @@ -152,6 +156,7 @@ Various ways to check your working tree:: > $ git diff <1> > $ git diff --cached <2> > $ git diff HEAD <3> > +$ git diff AUTO_MERGE <4> > ------------ > + > <1> Changes in the working tree not yet staged for the next commit. > @@ -159,6 +164,7 @@ $ git diff HEAD <3> > would be committing if you run `git commit` without `-a` option. > <3> Changes in the working tree since your last commit; what you > would be committing if you run `git commit -a` > +<4> Changes in the working tree you've made to resolve conflicts so far. > > Comparing with arbitrary commits:: > + > diff --git a/Documentation/git-merge.txt b/Documentation/git-merge.txt > index 23aefe28851..3f61389c1c2 100644 > --- a/Documentation/git-merge.txt > +++ b/Documentation/git-merge.txt > @@ -196,7 +196,11 @@ happens: > can inspect the stages with `git ls-files -u`). The working > tree files contain the result of the merge operation; i.e. 3-way > merge results with familiar conflict markers `<<<` `===` `>>>`. > -5. No other changes are made. In particular, the local > +5. A special ref `AUTO_MERGE` is written, pointing to a tree corresponding > + to the current content of the working tree (including conflict markers). > + Note that this ref is only written when the 'ort' merge strategy > + is used (the default). > +6. No other changes are made. In particular, the local > modifications you had before you started merge will stay the > same and the index entries for them stay as they were, > i.e. matching `HEAD`. > @@ -336,7 +340,8 @@ You can work through the conflict with a number of tools: > > * Look at the diffs. `git diff` will show a three-way diff, > highlighting changes from both the `HEAD` and `MERGE_HEAD` > - versions. > + versions. `git diff AUTO_MERGE` will show what changes you've > + made so far to resolve conlicts. s/conlicts/conflicts/ > > * Look at the diffs from each branch. `git log --merge -p <path>` > will show diffs first for the `HEAD` version and then the > diff --git a/Documentation/revisions.txt b/Documentation/revisions.txt > index 98b8f89bc8d..b42a2bb30a5 100644 > --- a/Documentation/revisions.txt > +++ b/Documentation/revisions.txt > @@ -33,7 +33,8 @@ characters and to avoid word splitting. > > . If '$GIT_DIR/<refname>' exists, that is what you mean (this is usually > useful only for `HEAD`, `FETCH_HEAD`, `ORIG_HEAD`, `MERGE_HEAD`, > - `REBASE_HEAD`, `REVERT_HEAD`, `CHERRY_PICK_HEAD` and `BISECT_HEAD`); > + `REBASE_HEAD`, `REVERT_HEAD`, `CHERRY_PICK_HEAD`, `BISECT_HEAD` > + and `AUTO_MERGE`); > > . otherwise, 'refs/<refname>' if it exists; > > @@ -64,6 +65,9 @@ run `git revert`. > when you run `git cherry-pick`. > `BISECT_HEAD` records the current commit to be tested when you > run `git bisect --no-checkout`. > +`AUTO_MERGE` records a tree object corresponding to the state the > +'ort' merge strategy wrote to the working tree when a merge operation > +resulted in conflicts. > + > Note that any of the 'refs/*' cases above may come either from > the `$GIT_DIR/refs` directory or from the `$GIT_DIR/packed-refs` file. > diff --git a/Documentation/user-manual.txt b/Documentation/user-manual.txt > index dc9c6a663a9..99e5f652e92 100644 > --- a/Documentation/user-manual.txt > +++ b/Documentation/user-manual.txt > @@ -1343,6 +1343,33 @@ $ git diff -3 file.txt # diff against stage 3 > $ git diff --theirs file.txt # same as the above. > ------------------------------------------------- > > +When using the 'ort' merge strategy (the default), before updating the working > +tree with the result of the merge, Git writes a special ref named AUTO_MERGE > +reflecting the state of the tree it is about to write. Conflicted paths that > +could not be automatically merged are written to this tree with conflict > +markers, just as in the working tree. AUTO_MERGE can thus be used with > +linkgit:git-diff[1] to show the changes you've made so far to resolve > +conflicts. Using the same example as above, after resolving the conflict we > +get: Mostly... To clarify, conflicted paths *with a textual conflict* are written with conflict markers. Conflicted paths with non-textual conflicts are not. There are several conflict types that fall into the non-textual conflict umbrella: binary files, file/directory, symlink/directory, symlink/file, modify/delete, rename/add, rename/delete, rename/rename (1to2), and various submodule and directory rename conflict types as well. The AUTO_MERGE stuff will only help with seeing how textual conflicts were resolved, it's not much help with the non-textual conflicts. (By contrast, the closely related --remerge-diff option to `git log` or `git show` does help see the resolution of *both* the textual and non-textual conflicts, but of course one can't use that option on the current merge until after first commiting the existing changes.) > + > +------------------------------------------------- > +$ git diff AUTO_MERGE > +diff --git a/file.txt b/file.txt > +index cd10406..8bf5ae7 100644 > +--- a/file.txt > ++++ b/file.txt > +@@ -1,5 +1 @@ > +-<<<<<<< HEAD:file.txt > +-Hello world > +-======= > +-Goodbye > +->>>>>>> 77976da35a11db4580b80ae27e8d65caf5208086:file.txt > ++Goodbye world > +------------------------------------------------- > + > +Notice that the diff shows we deleted the conflict markers and both versions, > +and wrote "Goodbye world" instead. > + > The linkgit:git-log[1] and linkgit:gitk[1] commands also provide special help > for merges: > > -- > gitgitgadget >
