merge_file should use more aggressive levels

The default merge_file level was XDL_MERGE_MINIMAL, which will
produce conflicts where there should not be in the case where
both sides were changed identically.  Change the defaults to be
more aggressive (XDL_MERGE_ZEALOUS) which will more aggressively
compress non-conflicts.  This matches git.git's defaults.

Increase testing around reverting a previously reverted commit to
illustrate this problem.

1 files changed, 198 insertions, 1 deletions

diff --git a/tests/revert/workdir.c b/tests/revert/workdir.c
index 9dc72a9a8..bca1ff926 100644
--- a/tests/revert/workdir.c
+++ b/tests/revert/workdir.c
@@ -137,6 +137,203 @@ void test_revert_workdir__orphan(void)
 	git_commit_free(head);
 }
 
+/*
+ * revert the same commit twice (when the first reverts cleanly):
+ *
+ * git revert 2d440f2
+ * git revert 2d440f2
+ */
+void test_revert_workdir__again(void)
+{
+	git_reference *head_ref;
+	git_commit *orig_head;
+	git_tree *reverted_tree;
+	git_oid reverted_tree_oid, reverted_commit_oid;
+	git_signature *signature;
+
+	struct merge_index_entry merge_index_entries[] = {
+		{ 0100644, "7731926a337c4eaba1e2187d90ebfa0a93659382", 0, "file1.txt" },
+		{ 0100644, "0ab09ea6d4c3634bdf6c221626d8b6f7dd890767", 0, "file2.txt" },
+		{ 0100644, "f4e107c230d08a60fb419d19869f1f282b272d9c", 0, "file3.txt" },
+		{ 0100644, "0f5bfcf58c558d865da6be0281d7795993646cee", 0, "file6.txt" },
+	};
+
+	cl_git_pass(git_repository_head(&head_ref, repo));
+	cl_git_pass(git_reference_peel((git_object **)&orig_head, head_ref, GIT_OBJ_COMMIT));
+	cl_git_pass(git_reset(repo, (git_object *)orig_head, GIT_RESET_HARD));
+
+	cl_git_pass(git_revert(repo, orig_head, NULL));
+
+	cl_assert(merge_test_index(repo_index, merge_index_entries, 4));
+
+	cl_git_pass(git_index_write_tree(&reverted_tree_oid, repo_index));
+	cl_git_pass(git_tree_lookup(&reverted_tree, repo, &reverted_tree_oid));
+
+	cl_git_pass(git_signature_new(&signature, "Reverter", "reverter@example.org", time(NULL), 0));
+	cl_git_pass(git_commit_create(&reverted_commit_oid, repo, "HEAD", signature, signature, NULL, "Reverted!", reverted_tree, 1, (const git_commit **)&orig_head));
+
+	cl_git_pass(git_revert(repo, orig_head, NULL));
+	cl_assert(merge_test_index(repo_index, merge_index_entries, 4));
+
+	git_signature_free(signature);
+	git_tree_free(reverted_tree);
+	git_commit_free(orig_head);
+	git_reference_free(head_ref);
+}
+
+/* git reset --hard 72333f47d4e83616630ff3b0ffe4c0faebcc3c45
+ * git revert --no-commit d1d403d22cbe24592d725f442835cf46fe60c8ac */
+void test_revert_workdir__again_after_automerge(void)
+{
+	git_commit *head, *commit;
+	git_tree *reverted_tree;
+	git_oid head_oid, revert_oid, reverted_tree_oid, reverted_commit_oid;
+	git_signature *signature;
+
+	struct merge_index_entry merge_index_entries[] = {
+		{ 0100644, "caf99de3a49827117bb66721010eac461b06a80c", 0, "file1.txt" },
+		{ 0100644, "0ab09ea6d4c3634bdf6c221626d8b6f7dd890767", 0, "file2.txt" },
+		{ 0100644, "f4e107c230d08a60fb419d19869f1f282b272d9c", 0, "file3.txt" },
+		{ 0100644, "0f5bfcf58c558d865da6be0281d7795993646cee", 0, "file6.txt" },
+	};
+
+	struct merge_index_entry second_revert_entries[] = {
+		{ 0100644, "3a3ef367eaf3fe79effbfb0a56b269c04c2b59fe", 1, "file1.txt" },
+		{ 0100644, "caf99de3a49827117bb66721010eac461b06a80c", 2, "file1.txt" },
+		{ 0100644, "747726e021bc5f44b86de60e3032fd6f9f1b8383", 3, "file1.txt" },
+		{ 0100644, "0ab09ea6d4c3634bdf6c221626d8b6f7dd890767", 0, "file2.txt" },
+		{ 0100644, "f4e107c230d08a60fb419d19869f1f282b272d9c", 0, "file3.txt" },
+		{ 0100644, "0f5bfcf58c558d865da6be0281d7795993646cee", 0, "file6.txt" },
+	};
+
+	git_oid_fromstr(&head_oid, "72333f47d4e83616630ff3b0ffe4c0faebcc3c45");
+	cl_git_pass(git_commit_lookup(&head, repo, &head_oid));
+	cl_git_pass(git_reset(repo, (git_object *)head, GIT_RESET_HARD));
+
+	git_oid_fromstr(&revert_oid, "d1d403d22cbe24592d725f442835cf46fe60c8ac");
+	cl_git_pass(git_commit_lookup(&commit, repo, &revert_oid));
+	cl_git_pass(git_revert(repo, commit, NULL));
+
+	cl_assert(merge_test_index(repo_index, merge_index_entries, 4));
+
+	cl_git_pass(git_index_write_tree(&reverted_tree_oid, repo_index));
+	cl_git_pass(git_tree_lookup(&reverted_tree, repo, &reverted_tree_oid));
+
+	cl_git_pass(git_signature_new(&signature, "Reverter", "reverter@example.org", time(NULL), 0));
+	cl_git_pass(git_commit_create(&reverted_commit_oid, repo, "HEAD", signature, signature, NULL, "Reverted!", reverted_tree, 1, (const git_commit **)&head));
+
+	cl_git_pass(git_revert(repo, commit, NULL));
+	cl_assert(merge_test_index(repo_index, second_revert_entries, 6));
+
+	git_signature_free(signature);
+	git_tree_free(reverted_tree);
+	git_commit_free(commit);
+	git_commit_free(head);
+}
+
+/*
+ * revert the same commit twice (when the first reverts cleanly):
+ *
+ * git revert 2d440f2
+ * git revert 2d440f2
+ */
+void test_revert_workdir__again_after_edit(void)
+{
+	git_reference *head_ref;
+	git_commit *orig_head, *commit;
+	git_tree *reverted_tree;
+	git_oid orig_head_oid, revert_oid, reverted_tree_oid, reverted_commit_oid;
+	git_signature *signature;
+
+	struct merge_index_entry merge_index_entries[] = {
+		{ 0100644, "3721552e06c4bdc7d478e0674e6304888545d5fd", 0, "file1.txt" },
+		{ 0100644, "0ab09ea6d4c3634bdf6c221626d8b6f7dd890767", 0, "file2.txt" },
+		{ 0100644, "f4e107c230d08a60fb419d19869f1f282b272d9c", 0, "file3.txt" },
+		{ 0100644, "0f5bfcf58c558d865da6be0281d7795993646cee", 0, "file6.txt" },
+	};
+
+	cl_git_pass(git_repository_head(&head_ref, repo));
+
+	cl_git_pass(git_oid_fromstr(&orig_head_oid, "399fb3aba3d9d13f7d40a9254ce4402067ef3149"));
+	cl_git_pass(git_commit_lookup(&orig_head, repo, &orig_head_oid));
+	cl_git_pass(git_reset(repo, (git_object *)orig_head, GIT_RESET_HARD));
+
+	cl_git_pass(git_oid_fromstr(&revert_oid, "2d440f2b3147d3dc7ad1085813478d6d869d5a4d"));
+	cl_git_pass(git_commit_lookup(&commit, repo, &revert_oid));
+
+	cl_git_pass(git_revert(repo, commit, NULL));
+
+	cl_assert(merge_test_index(repo_index, merge_index_entries, 4));
+
+	cl_git_pass(git_index_write_tree(&reverted_tree_oid, repo_index));
+	cl_git_pass(git_tree_lookup(&reverted_tree, repo, &reverted_tree_oid));
+
+	cl_git_pass(git_signature_new(&signature, "Reverter", "reverter@example.org", time(NULL), 0));
+	cl_git_pass(git_commit_create(&reverted_commit_oid, repo, "HEAD", signature, signature, NULL, "Reverted!", reverted_tree, 1, (const git_commit **)&orig_head));
+
+	cl_git_pass(git_revert(repo, commit, NULL));
+	cl_assert(merge_test_index(repo_index, merge_index_entries, 4));
+
+	git_signature_free(signature);
+	git_tree_free(reverted_tree);
+	git_commit_free(commit);
+	git_commit_free(orig_head);
+	git_reference_free(head_ref);
+}
+
+/*
+ * revert the same commit twice (when the first reverts cleanly):
+ *
+ * git reset --hard e34ef1a
+ * git revert 71eb9c2
+ */
+void test_revert_workdir__again_after_edit_two(void)
+{
+	git_buf diff_buf = GIT_BUF_INIT;
+	git_config *config;
+	git_oid head_commit_oid, revert_commit_oid;
+	git_commit *head_commit, *revert_commit;
+
+	struct merge_index_entry merge_index_entries[] = {
+		{ 0100644, "1ff0c423042b46cb1d617b81efb715defbe8054d", 0, ".gitattributes" },
+		{ 0100644, "1bc915c5cb7185a9438de28a7b1a7dfe8c01ee7f", 0, ".gitignore" },
+		{ 0100644, "a8c86221b400b836010567cc3593db6e96c1a83a", 1, "file.txt" },
+		{ 0100644, "46ff0854663aeb2182b9838c8da68e33ac23bc1e", 2, "file.txt" },
+		{ 0100644, "21a96a98ed84d45866e1de6e266fd3a61a4ae9dc", 3, "file.txt" },
+	};
+
+	cl_git_pass(git_repository_config(&config, repo));
+	cl_git_pass(git_config_set_bool(config, "core.autocrlf", 0));
+
+	cl_git_pass(git_oid_fromstr(&head_commit_oid, "e34ef1afe54eb526fd92eec66084125f340f1d65"));
+	cl_git_pass(git_commit_lookup(&head_commit, repo, &head_commit_oid));
+	cl_git_pass(git_reset(repo, (git_object *)head_commit, GIT_RESET_HARD));
+
+	cl_git_pass(git_oid_fromstr(&revert_commit_oid, "71eb9c2b53dbbf3c45fb28b27c850db4b7fb8011"));
+	cl_git_pass(git_commit_lookup(&revert_commit, repo, &revert_commit_oid));
+
+	cl_git_pass(git_revert(repo, revert_commit, NULL));
+
+	cl_assert(merge_test_index(repo_index, merge_index_entries, 5));
+
+	cl_git_pass(git_futils_readbuffer(&diff_buf, "revert/file.txt"));
+	cl_assert(strcmp(diff_buf.ptr,	"a\n" \
+		"<<<<<<< HEAD\n" \
+		"=======\n" \
+		"a\n" \
+		">>>>>>> parent of 71eb9c2... revert me\n" \
+		"a\n" \
+		"a\n" \
+		"a\n" \
+		"a\n" \
+		"ab\n") == 0);
+
+	git_commit_free(revert_commit);
+	git_commit_free(head_commit);
+	git_config_free(config);
+	git_buf_free(&diff_buf);
+}
+
 /* git reset --hard 72333f47d4e83616630ff3b0ffe4c0faebcc3c45
  * git revert --no-commit d1d403d22cbe24592d725f442835cf46fe60c8ac */
 void test_revert_workdir__conflict_use_ours(void)
@@ -161,7 +358,7 @@ void test_revert_workdir__conflict_use_ours(void)
 		{ 0100644, "0f5bfcf58c558d865da6be0281d7795993646cee", 0, "file6.txt" },
 	};
 
-	opts.merge_tree_opts.automerge_flags = GIT_MERGE_AUTOMERGE_NONE;
+	opts.merge_tree_opts.file_favor = GIT_MERGE_FILE_FAVOR_NO_MERGE;
 	opts.checkout_opts.checkout_strategy = GIT_CHECKOUT_SAFE | GIT_CHECKOUT_USE_OURS;
 
 	git_oid_fromstr(&head_oid, "72333f47d4e83616630ff3b0ffe4c0faebcc3c45");