t2031: verify that git init can create a long path

This currently fails, with:

	++ p=/123456789abcdef/123456789abcdef/123456789abcdef/123456789abc/ef
	++ p=y/123456789abcdef/123456789abcdef/123456789abcdef/123456789abc/ef/123456789abcdef/123456789abcdef/123456789abcdef/123456789abc/ef/123456789abcdef/123456789abcdef/123456789abcdef/123456789abc/ef/123456789abcdef/123456789abcdef/123456789abcdef/123456789abc/ef
	++ test_config_global core.longpaths true
	++ test_when_finished 'test_unconfig --global '\''core.longpaths'\'''
	++ test 0 = 0
	++ test_cleanup='{ test_unconfig --global '\''core.longpaths'\''
			} && (exit "$eval_ret"); eval_ret=$?; :'
	++ git config --global core.longpaths true
	++ git init y/123456789abcdef/123456789abcdef/123456789abcdef/123456789abc/ef/123456789abcdef/123456789abcdef/123456789abcdef/123456789abc/ef/123456789abcdef/123456789abcdef/123456789abcdef/123456789abc/ef/123456789abcdef/123456789abcdef/123456789abcdef/123456789abc/ef
	fatal: cannot chdir to y/123456789abcdef/123456789abcdef/123456789abcdef/123456789abc/ef/123456789abcdef/123456789abcdef/123456789abcdef/123456789abc/ef/123456789abcdef/123456789abcdef/123456789abcdef/123456789abc/ef/123456789abcdef/123456789abcdef/123456789abcdef/123456789abc/ef: No such file or directory
	error: last command exited with $?=128
	not ok 7 - init with long path

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

t/t2031-checkout-long-paths.sh

@@ -99,4 +99,11 @@ test_expect_success SHORTABSPATH 'clean up path close to MAX_PATH' '
 	test ! -d "$subdir1"
 '
 
+test_expect_success 'init with long path' '
+	p=/123456789abcdef/123456789abcdef/123456789abcdef/123456789abc/ef &&
+	p=y$p$p$p$p &&
+	test_config_global core.longpaths true &&
+	git init $p
+'
+
 test_done