[PATCH v6 2/6] Simplify default branch comparison logic

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

From: Harald Nordgren <haraldnordgren@gmail.com>

This maintains the same functionality while reducing ref resolution calls
from multiple to one, and eliminating unnecessary memory allocations.

Signed-off-by: Harald Nordgren <haraldnordgren@gmail.com>
---
 remote.c | 59 ++++++++++++++++++--------------------------------------
 1 file changed, 19 insertions(+), 40 deletions(-)

diff --git a/remote.c b/remote.c
index b2a1e980b1..f3831ef3be 100644
--- a/remote.c
+++ b/remote.c
@@ -2267,41 +2267,17 @@ static char *get_default_remote_ref(char **full_ref_out)
 	return NULL;
 }
 
-static int is_default_remote_branch(const char *name)
-{
-	char *default_full = NULL;
-	char *default_short;
-	int result = 0;
-
-	default_short = get_default_remote_ref(&default_full);
-	if (!default_short)
-		return 0;
-
-	result = !strcmp(name, default_short);
-
-	free(default_short);
-	free(default_full);
-	return result;
-}
-
 static void format_default_branch_comparison(struct strbuf *sb,
 					     const char *branch_refname,
+					     const char *default_full,
+					     const char *default_short,
 					     enum ahead_behind_flags abf)
 {
 	int default_ours = 0, default_theirs = 0;
-	char *default_full = NULL;
-	char *default_short;
-
-	default_short = get_default_remote_ref(&default_full);
-	if (!default_short)
-		return;
 
 	if (stat_branch_pair(branch_refname, default_full,
-			     &default_ours, &default_theirs, abf) <= 0) {
-		free(default_short);
-		free(default_full);
+			     &default_ours, &default_theirs, abf) <= 0)
 		return;
-	}
 
 	strbuf_addstr(sb, "\n");
 
@@ -2324,9 +2300,6 @@ static void format_default_branch_comparison(struct strbuf *sb,
 			   default_ours + default_theirs),
 			default_short, default_ours + default_theirs);
 	}
-
-	free(default_short);
-	free(default_full);
 }
 
 /*
@@ -2340,7 +2313,8 @@ int format_tracking_info(struct branch *branch, struct strbuf *sb,
 	const char *full_base;
 	char *base;
 	int upstream_is_gone = 0;
-	int show_default_branch_comparison;
+	char *default_full = NULL;
+	char *default_short = NULL;
 
 	sti = stat_tracking_info(branch, &ours, &theirs, &full_base, 0, abf);
 	if (sti < 0) {
@@ -2352,7 +2326,13 @@ int format_tracking_info(struct branch *branch, struct strbuf *sb,
 	base = refs_shorten_unambiguous_ref(get_main_ref_store(the_repository),
 					    full_base, 0);
 
-	show_default_branch_comparison = !is_default_remote_branch(base);
+	default_short = get_default_remote_ref(&default_full);
+	if (default_short && !strcmp(base, default_short)) {
+		free(default_short);
+		free(default_full);
+		default_short = NULL;
+		default_full = NULL;
+	}
 
 	if (upstream_is_gone) {
 		strbuf_addf(sb,
@@ -2365,8 +2345,6 @@ int format_tracking_info(struct branch *branch, struct strbuf *sb,
 		strbuf_addf(sb,
 			_("Your branch is up to date with '%s'.\n"),
 			base);
-		if (show_default_branch_comparison)
-			format_default_branch_comparison(sb, branch->refname, abf);
 	} else if (abf == AHEAD_BEHIND_QUICK) {
 		strbuf_addf(sb,
 			    _("Your branch and '%s' refer to different commits.\n"),
@@ -2383,8 +2361,6 @@ int format_tracking_info(struct branch *branch, struct strbuf *sb,
 		if (advice_enabled(ADVICE_STATUS_HINTS))
 			strbuf_addstr(sb,
 				_("  (use \"git push\" to publish your local commits)\n"));
-		if (show_default_branch_comparison)
-			format_default_branch_comparison(sb, branch->refname, abf);
 	} else if (!ours) {
 		strbuf_addf(sb,
 			Q_("Your branch is behind '%s' by %d commit, "
@@ -2396,8 +2372,6 @@ int format_tracking_info(struct branch *branch, struct strbuf *sb,
 		if (advice_enabled(ADVICE_STATUS_HINTS))
 			strbuf_addstr(sb,
 				_("  (use \"git pull\" to update your local branch)\n"));
-		if (show_default_branch_comparison)
-			format_default_branch_comparison(sb, branch->refname, abf);
 	} else {
 		strbuf_addf(sb,
 			Q_("Your branch and '%s' have diverged,\n"
@@ -2412,10 +2386,15 @@ int format_tracking_info(struct branch *branch, struct strbuf *sb,
 		    advice_enabled(ADVICE_STATUS_HINTS))
 			strbuf_addstr(sb,
 				_("  (use \"git pull\" if you want to integrate the remote branch with yours)\n"));
-		if (show_default_branch_comparison)
-			format_default_branch_comparison(sb, branch->refname, abf);
 	}
+
+	if (default_short && !upstream_is_gone && sti >= 0 && abf != AHEAD_BEHIND_QUICK)
+		format_default_branch_comparison(sb, branch->refname, default_full,
+						 default_short, abf);
+
 	free(base);
+	free(default_short);
+	free(default_full);
 	return 1;
 }
 
-- 
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