branch: remove config section upon deletion

src/branch.c

@@ -89,6 +89,50 @@ cleanup:
 	return error;
 }
 
+static int delete_config_entries_cb(
+	const char *var_name,
+	const char *value,
+	void *payload)
+{
+	git_config *config;
+
+	GIT_UNUSED(value);
+
+	config = (git_config *)payload;
+
+	return git_config_delete(config, var_name);
+}
+
+static int delete_branch_config_entries(
+	git_repository *repo,
+	const char *branch_name)
+{
+	git_config *config;
+	git_buf pattern = GIT_BUF_INIT;
+	int error = -1;
+
+	git_buf_sets(&pattern, "branch\\.");
+	git_buf_puts_escape_regex(&pattern,  branch_name);
+	git_buf_puts(&pattern, "\\..+");
+	if (git_buf_oom(&pattern))
+		goto cleanup;
+
+	if (git_repository_config__weakptr(&config, repo) < 0)
+		goto cleanup;
+
+	if ((error = git_config_foreach_match(
+			config,
+			git_buf_cstr(&pattern),
+			delete_config_entries_cb, config)) < 0)
+		goto cleanup;
+
+	error = 0;
+
+cleanup:
+	git_buf_free(&pattern);
+	return error;
+}
+
 int git_branch_delete(git_reference *branch)
 {
 	int is_head;
@@ -110,6 +154,11 @@ int git_branch_delete(git_reference *branch)
 		return -1;
 	}
 
+	if (delete_branch_config_entries(
+		git_reference_owner(branch), 
+		git_reference_name(branch) + strlen(GIT_REFS_HEADS_DIR)) < 0)
+			goto on_error;
+
 	return git_reference_delete(branch);
 }
 

tests-clar/config/config_helpers.c

@@ -0,0 +1,22 @@
+#include "clar_libgit2.h"
+#include "config_helpers.h"
+#include "repository.h"
+
+void assert_config_entry_existence(
+	git_repository *repo,
+	const char *name,
+	bool is_supposed_to_exist)
+{
+	git_config *config;
+	const char *out;
+	int result;
+
+	cl_git_pass(git_repository_config__weakptr(&config, repo));
+	
+	result = git_config_get_string(&out, config, name);
+
+	if (is_supposed_to_exist)
+		cl_git_pass(result);
+	else
+		cl_assert_equal_i(GIT_ENOTFOUND, result);
+}

tests-clar/config/config_helpers.h

@@ -0,0 +1,4 @@
+extern void assert_config_entry_existence(
+	git_repository *repo,
+	const char *name,
+	bool is_supposed_to_exist);

tests-clar/refs/branches/delete.c

@@ -1,6 +1,7 @@
 #include "clar_libgit2.h"
 #include "refs.h"
 #include "repo/repo_helpers.h"
+#include "config/config_helpers.h"
 
 static git_repository *repo;
 static git_reference *fake_remote;
@@ -90,3 +91,17 @@ void test_refs_branches_delete__can_delete_a_remote_branch(void)
 	cl_git_pass(git_branch_lookup(&branch, repo, "nulltoken/master", GIT_BRANCH_REMOTE));
 	cl_git_pass(git_branch_delete(branch));
 }
+
+void test_refs_branches_delete__deleting_a_branch_removes_related_configuration_data(void)
+{
+	git_reference *branch;
+
+	assert_config_entry_existence(repo, "branch.track-local.remote", true);
+	assert_config_entry_existence(repo, "branch.track-local.merge", true);
+
+	cl_git_pass(git_branch_lookup(&branch, repo, "track-local", GIT_BRANCH_LOCAL));
+	cl_git_pass(git_branch_delete(branch));
+
+	assert_config_entry_existence(repo, "branch.track-local.remote", false);
+	assert_config_entry_existence(repo, "branch.track-local.merge", false);
+}