diff --git a/builtin/clean.c b/builtin/clean.c
index df53def63..d7acb94a9 100644
--- a/builtin/clean.c
+++ b/builtin/clean.c
@@ -159,8 +159,7 @@ static int is_git_repository(struct strbuf *path)
 	int gitfile_error;
 	size_t orig_path_len = path->len;
 	assert(orig_path_len != 0);
-	if (path->buf[orig_path_len - 1] != '/')
-		strbuf_addch(path, '/');
+	strbuf_complete(path, '/');
 	strbuf_addstr(path, ".git");
 	if (read_gitfile_gently(path->buf, &gitfile_error) || is_git_directory(path->buf))
 		ret = 1;
@@ -206,8 +205,7 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
 		return res;
 	}
 
-	if (path->buf[original_len - 1] != '/')
-		strbuf_addch(path, '/');
+	strbuf_complete(path, '/');
 
 	len = path->len;
 	while ((e = readdir(dir)) != NULL) {
diff --git a/builtin/log.c b/builtin/log.c
index a491d3dea..dda671d97 100644
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -796,8 +796,7 @@ static int reopen_stdout(struct commit *commit, const char *subject,
 		if (filename.len >=
 		    PATH_MAX - FORMAT_PATCH_NAME_MAX - suffix_len)
 			return error(_("name of output directory is too long"));
-		if (filename.buf[filename.len - 1] != '/')
-			strbuf_addch(&filename, '/');
+		strbuf_complete(&filename, '/');
 	}
 
 	if (rev->numbered_files)
diff --git a/diff-no-index.c b/diff-no-index.c
index 0320605a8..8e0fd270b 100644
--- a/diff-no-index.c
+++ b/diff-no-index.c
@@ -136,15 +136,13 @@ static int queue_diff(struct diff_options *o,
 
 		if (name1) {
 			strbuf_addstr(&buffer1, name1);
-			if (buffer1.len && buffer1.buf[buffer1.len - 1] != '/')
-				strbuf_addch(&buffer1, '/');
+			strbuf_complete(&buffer1, '/');
 			len1 = buffer1.len;
 		}
 
 		if (name2) {
 			strbuf_addstr(&buffer2, name2);
-			if (buffer2.len && buffer2.buf[buffer2.len - 1] != '/')
-				strbuf_addch(&buffer2, '/');
+			strbuf_complete(&buffer2, '/');
 			len2 = buffer2.len;
 		}
 
diff --git a/dir.c b/dir.c
index 7b2563483..79fdad842 100644
--- a/dir.c
+++ b/dir.c
@@ -1519,8 +1519,7 @@ static enum path_treatment treat_path_fast(struct dir_struct *dir,
 	}
 	strbuf_addstr(path, cdir->ucd->name);
 	/* treat_one_path() does this before it calls treat_directory() */
-	if (path->buf[path->len - 1] != '/')
-		strbuf_addch(path, '/');
+	strbuf_complete(path, '/');
 	if (cdir->ucd->check_only)
 		/*
 		 * check_only is set as a result of treat_directory() getting
@@ -2126,8 +2125,7 @@ static int remove_dir_recurse(struct strbuf *path, int flag, int *kept_up)
 		else
 			return -1;
 	}
-	if (path->buf[original_len - 1] != '/')
-		strbuf_addch(path, '/');
+	strbuf_complete(path, '/');
 
 	len = path->len;
 	while ((e = readdir(dir)) != NULL) {
diff --git a/path.c b/path.c
index c597473e6..c105a9e08 100644
--- a/path.c
+++ b/path.c
@@ -240,8 +240,7 @@ static void do_submodule_path(struct strbuf *buf, const char *path,
 	const char *git_dir;
 
 	strbuf_addstr(buf, path);
-	if (buf->len && buf->buf[buf->len - 1] != '/')
-		strbuf_addch(buf, '/');
+	strbuf_complete(buf, '/');
 	strbuf_addstr(buf, ".git");
 
 	git_dir = read_gitfile(buf->buf);
diff --git a/refs.c b/refs.c
index 9937a4048..b2a922945 100644
--- a/refs.c
+++ b/refs.c
@@ -2193,8 +2193,7 @@ int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
 
 	if (!has_glob_specials(pattern)) {
 		/* Append implied '/' '*' if not present. */
-		if (real_pattern.buf[real_pattern.len - 1] != '/')
-			strbuf_addch(&real_pattern, '/');
+		strbuf_complete(&real_pattern, '/');
 		/* No need to check for '*', there is none. */
 		strbuf_addch(&real_pattern, '*');
 	}
diff --git a/url.c b/url.c
index 7ca2a69e1..2d89ad190 100644
--- a/url.c
+++ b/url.c
@@ -120,8 +120,7 @@ char *url_decode_parameter_value(const char **query)
 void end_url_with_slash(struct strbuf *buf, const char *url)
 {
 	strbuf_addstr(buf, url);
-	if (buf->len && buf->buf[buf->len - 1] != '/')
-		strbuf_addch(buf, '/');
+	strbuf_complete(buf, '/');
 }
 
 void str_end_url_with_slash(const char *url, char **dest) {