config: drop support for GIT_CONFIG_NOGLOBAL

Now that test-lib sets $HOME to protect against pollution from user
settings, GIT_CONFIG_NOGLOBAL is not needed for use by the test
suite any more.  And as luck would have it, a quick code search
reveals no other users in the wild.

This patch does not affect GIT_CONFIG_NOSYSTEM, which is still
needed.

Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/builtin/config.c b/builtin/config.c
index 76be0b7..3e3c528 100644
--- a/builtin/config.c
+++ b/builtin/config.c
@@ -160,7 +160,7 @@
 	if (!local) {
 		const char *home = getenv("HOME");
 		local = repo_config = git_pathdup("config");
-		if (git_config_global() && home)
+		if (home)
 			global = xstrdup(mkpath("%s/.gitconfig", home));
 		if (git_config_system())
 			system_wide = git_etc_gitconfig();
diff --git a/cache.h b/cache.h
index d0bbc91..a8ef37a 100644
--- a/cache.h
+++ b/cache.h
@@ -1020,7 +1020,6 @@
 extern int check_repository_format_version(const char *var, const char *value, void *cb);
 extern int git_env_bool(const char *, int);
 extern int git_config_system(void);
-extern int git_config_global(void);
 extern int config_error_nonbool(const char *);
 extern const char *get_log_output_encoding(void);
 extern const char *get_commit_output_encoding(void);
diff --git a/config.c b/config.c
index b94de8f..217a77d 100644
--- a/config.c
+++ b/config.c
@@ -826,11 +826,6 @@
 	return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
 }
 
-int git_config_global(void)
-{
-	return !git_env_bool("GIT_CONFIG_NOGLOBAL", 0);
-}
-
 int git_config_from_parameters(config_fn_t fn, void *data)
 {
 	static int loaded_environment;
@@ -862,7 +857,7 @@
 	}
 
 	home = getenv("HOME");
-	if (git_config_global() && home) {
+	if (home) {
 		char *user_config = xstrdup(mkpath("%s/.gitconfig", home));
 		if (!access(user_config, R_OK)) {
 			ret += git_config_from_file(fn, user_config, data);
diff --git a/t/t0001-init.sh b/t/t0001-init.sh
index f684993..ce4ba13 100755
--- a/t/t0001-init.sh
+++ b/t/t0001-init.sh
@@ -47,7 +47,7 @@
 
 test_expect_success 'plain through aliased command, outside any git repo' '
 	(
-		sane_unset GIT_DIR GIT_WORK_TREE GIT_CONFIG_NOGLOBAL &&
+		sane_unset GIT_DIR GIT_WORK_TREE &&
 		HOME=$(pwd)/alias-config &&
 		export HOME &&
 		mkdir alias-config &&
@@ -231,7 +231,6 @@
 		git config -f "$test_config"  init.templatedir "${HOME}/templatedir-source" &&
 		mkdir templatedir-set &&
 		cd templatedir-set &&
-		sane_unset GIT_CONFIG_NOGLOBAL &&
 		sane_unset GIT_TEMPLATE_DIR &&
 		NO_SET_GIT_TEMPLATE_DIR=t &&
 		export NO_SET_GIT_TEMPLATE_DIR &&
@@ -243,7 +242,6 @@
 test_expect_success 'init --bare/--shared overrides system/global config' '
 	(
 		test_config="$HOME"/.gitconfig &&
-		sane_unset GIT_CONFIG_NOGLOBAL &&
 		git config -f "$test_config" core.bare false &&
 		git config -f "$test_config" core.sharedRepository 0640 &&
 		mkdir init-bare-shared-override &&
@@ -258,7 +256,6 @@
 test_expect_success 'init honors global core.sharedRepository' '
 	(
 		test_config="$HOME"/.gitconfig &&
-		sane_unset GIT_CONFIG_NOGLOBAL &&
 		git config -f "$test_config" core.sharedRepository 0666 &&
 		mkdir shared-honor-global &&
 		cd shared-honor-global &&
diff --git a/t/t5601-clone.sh b/t/t5601-clone.sh
index 987e0c8..3ca275c 100755
--- a/t/t5601-clone.sh
+++ b/t/t5601-clone.sh
@@ -164,7 +164,6 @@
 test_expect_success 'clone respects global branch.autosetuprebase' '
 	(
 		test_config="$HOME/.gitconfig" &&
-		unset GIT_CONFIG_NOGLOBAL &&
 		git config -f "$test_config" branch.autosetuprebase remote &&
 		rm -fr dst &&
 		git clone src dst &&
diff --git a/t/t9130-git-svn-authors-file.sh b/t/t9130-git-svn-authors-file.sh
index ec0a106..b324c49 100755
--- a/t/t9130-git-svn-authors-file.sh
+++ b/t/t9130-git-svn-authors-file.sh
@@ -96,7 +96,6 @@
 		rm -r "$GIT_DIR" &&
 		test x = x"$(git config svn.authorsfile)" &&
 		test_config="$HOME"/.gitconfig &&
-		unset GIT_CONFIG_NOGLOBAL &&
 		unset GIT_DIR &&
 		unset GIT_CONFIG &&
 		git config --global \
diff --git a/t/test-lib.sh b/t/test-lib.sh
index 00f23fc..8893406 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -947,9 +947,8 @@
 GIT_TEMPLATE_DIR="$GIT_BUILD_DIR"/templates/blt
 unset GIT_CONFIG
 GIT_CONFIG_NOSYSTEM=1
-GIT_CONFIG_NOGLOBAL=1
 GIT_ATTR_NOSYSTEM=1
-export PATH GIT_EXEC_PATH GIT_TEMPLATE_DIR GIT_CONFIG_NOSYSTEM GIT_CONFIG_NOGLOBAL GIT_ATTR_NOSYSTEM
+export PATH GIT_EXEC_PATH GIT_TEMPLATE_DIR GIT_CONFIG_NOSYSTEM GIT_ATTR_NOSYSTEM
 
 . "$GIT_BUILD_DIR"/GIT-BUILD-OPTIONS