Teach the builtin rebase about the builtin interactive rebase

The builtin rebase and the builtin interactive rebase have been developed independently, on purpose: Google Summer of Code rules specifically state that students have to work on independent projects, they cannot collaborate on the same project.

The reason is probably the very fine tradition in academia to prohibit teamwork, which makes grading easier (at the expense of not exactly preparing the students for the real world, unless they want to stay in academia).

One fallout is that the rebase-in-c and rebase-i-in-c patches cause no merge conflicts but a royal number of tests in the test suite to fail.

It is easy to explain why: rebase-in-c was developed under the assumption that all rebase backends are implemented in Unix shell script and can be sourced via . git-rebase--<backend>, which is no longer true with rebase-i-in-c, where git-rebase--interactive is a hard-linked builtin.

This patch fixes that.

Note: while this patch targets pk/rebase-in-c-6-final, it will not work correctly without ag/rebase-i-in-c. So my suggestion is to rewrite the pk/rebas-in-c-6-final branch by first merging ag/rebase-i-in-c, then applying this here patch, and only then cherry-pick "rebase: default to using the builtin rebase".

Changes since v2:

* Prepare for the break command, by skipping the call to finish_rebase() for interactive rebases altogether (the built-in interactive rebase already takes care of that).
* Remove a no-longer-used case arm (skipped by the newly-introduced code).

Changes since v1:

* replaced the too-terse commit message by a copy-edited version of this cover letter (leaving out only the rant about disallowing teamwork).

Johannes Schindelin (1):
builtin rebase: prepare for builtin rebase -i

 builtin/rebase.c | 87 +++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 83 insertions(+), 4 deletions(-)

base-commit: 67e0df2f391ec4177942a4d8b70e530aa5653c0d
Published-As: https://github.com/gitgitgadget/git/releases/tags/pr-23%2Fdscho%2Frebase-in-c-6-final-v3
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-23/dscho/rebase-in-c-6-final-v3
Pull-Request: https://github.com/gitgitgadget/git/pull/23

Range-diff vs v2:

1: 5403014be7 ! 1: db1652ef3e builtin rebase: prepare for builtin rebase -i
@@ -18,6 +18,15 @@

This patch fixes that.

+ Please note that we also skip the finish_rebase() call for interactive
+ rebases because the built-in interactive rebase already takes care of
+ that. This is needed to support the upcoming break command that wants
+ to interrupt the rebase with exit code 0 (and naturally wants to keep
+ the state directory intact when doing so).
+
+ While at it, remove the case arm for the interactive rebase that is
+ now skipped in favor of the short-cut to the built-in rebase.
+

diff --git a/builtin/rebase.c b/builtin/rebase.c
@@ -117,6 +126,17 @@
add_var(&script_snippet, "GIT_DIR", absolute_path(get_git_dir())); add_var(&script_snippet, "state_dir", opts->state_dir);

+@@
+ backend = "git-rebase--am";
+ backend_func = "git_rebase__am";
+ break;
+- case REBASE_INTERACTIVE:
+- backend = "git-rebase--interactive";
+- backend_func = "git_rebase__interactive";
+- break;
+ case REBASE_MERGE:
+ backend = "git-rebase--merge";
+ backend_func = "git_rebase__merge";
@@
argv[0] = script_snippet.buf;

@@ -124,4 +144,8 @@
+finished_rebase:
if (opts->dont_finish_rebase)
; /* do nothing */
++ else if (opts->type == REBASE_INTERACTIVE)
++ ; /* interactive rebase cleans up after itself */
else if (status == 0) {
+ if (!file_exists(state_dir_path("stopped-sha", opts)))
+ finish_rebase(opts);

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