[PATCH v8 2/5] branch: let delete_branches warn instead of error on bulk refusal

["Harald Nordgren via GitGitGadget" <gitgitgadget@gmail.com>]

From: Harald Nordgren <haraldnordgren@gmail.com>

Add two new parameters to delete_branches() and the helper
check_branch_commit():

* warn_only switches the per-branch refusal from a hard error
  ("error: the branch 'X' is not fully merged" plus a four-line
  hint about 'git branch -D X') to a one-line warning, and
  causes the function to skip those branches without setting its
  exit code. Each refused branch is still skipped from deletion.
* n_not_merged, when non-NULL, is incremented for each branch
  refused on the not-merged path, so a bulk caller can summarize
  rather than print per-branch advice.

All existing call sites pass 0 / NULL and so are unaffected. Both
parameters are wired up so a bulk-deletion caller can suppress
the noise normally appropriate for a one-shot 'git branch -d'.

Signed-off-by: Harald Nordgren <haraldnordgren@gmail.com>
---
 builtin/branch.c | 29 ++++++++++++++++++++---------
 1 file changed, 20 insertions(+), 9 deletions(-)

diff --git a/builtin/branch.c b/builtin/branch.c
index b3289a8875..1941f8a9ad 100644
--- a/builtin/branch.c
+++ b/builtin/branch.c
@@ -192,7 +192,8 @@ static int branch_merged(int kind, const char *name,
 
 static int check_branch_commit(const char *branchname, const char *refname,
 			       const struct object_id *oid, struct commit *head_rev,
-			       int kinds, int force)
+			       int kinds, int force, int warn_only,
+			       int *n_not_merged)
 {
 	struct commit *rev = lookup_commit_reference(the_repository, oid);
 	if (!force && !rev) {
@@ -200,10 +201,18 @@ static int check_branch_commit(const char *branchname, const char *refname,
 		return -1;
 	}
 	if (!force && !branch_merged(kinds, branchname, rev, head_rev)) {
-		error(_("the branch '%s' is not fully merged"), branchname);
-		advise_if_enabled(ADVICE_FORCE_DELETE_BRANCH,
-				  _("If you are sure you want to delete it, "
-				  "run 'git branch -D %s'"), branchname);
+		if (warn_only) {
+			warning(_("the branch '%s' is not fully merged"),
+				branchname);
+		} else {
+			error(_("the branch '%s' is not fully merged"),
+			      branchname);
+			advise_if_enabled(ADVICE_FORCE_DELETE_BRANCH,
+					  _("If you are sure you want to delete it, "
+					  "run 'git branch -D %s'"), branchname);
+		}
+		if (n_not_merged)
+			(*n_not_merged)++;
 		return -1;
 	}
 	return 0;
@@ -219,7 +228,7 @@ static void delete_branch_config(const char *branchname)
 }
 
 static int delete_branches(int argc, const char **argv, int force, int kinds,
-			   int quiet)
+			   int quiet, int warn_only, int *n_not_merged)
 {
 	struct commit *head_rev = NULL;
 	struct object_id oid;
@@ -309,8 +318,9 @@ static int delete_branches(int argc, const char **argv, int force, int kinds,
 
 		if (!(flags & (REF_ISSYMREF|REF_ISBROKEN)) &&
 		    check_branch_commit(bname.buf, name, &oid, head_rev, kinds,
-					force)) {
-			ret = 1;
+					force, warn_only, n_not_merged)) {
+			if (!warn_only)
+				ret = 1;
 			goto next;
 		}
 
@@ -961,7 +971,8 @@ int cmd_branch(int argc,
 	if (delete) {
 		if (!argc)
 			die(_("branch name required"));
-		ret = delete_branches(argc, argv, delete > 1, filter.kind, quiet);
+		ret = delete_branches(argc, argv, delete > 1, filter.kind,
+				      quiet, 0, NULL);
 		goto out;
 	} else if (forked) {
 		ret = list_forked_branches(argc, argv);
-- 
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