t1300: create custom config file without special characters

Tests that required a custom configuration file to be created previously
used a file with non-alphanumeric characters including escaped double
quotes.  This is not really necessary for the majority of tests
involving custom config files, and decreases test coverage on systems
that dissallow such filenames (Windows, etc.).

Create two files, one appropriate for testing quoting and one
appropriate for general use.

Signed-off-by: Matthew Rogers <mattr94@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t1300-config.sh

@@ -1710,18 +1710,23 @@ test_expect_success '--show-origin getting a single key' '
 '
 
 test_expect_success 'set up custom config file' '
-	CUSTOM_CONFIG_FILE="file\" (dq) and spaces.conf" &&
+	CUSTOM_CONFIG_FILE="custom.conf" &&
 	cat >"$CUSTOM_CONFIG_FILE" <<-\EOF
 	[user]
 		custom = true
 	EOF
 '
 
+test_expect_success !MINGW 'set up custom config file with special name characters' '
+	WEIRDLY_NAMED_FILE="file\" (dq) and spaces.conf" &&
+	cp "$CUSTOM_CONFIG_FILE" "$WEIRDLY_NAMED_FILE"
+'
+
 test_expect_success !MINGW '--show-origin escape special file name characters' '
 	cat >expect <<-\EOF &&
 	file:"file\" (dq) and spaces.conf"	user.custom=true
 	EOF
-	git config --file "$CUSTOM_CONFIG_FILE" --show-origin --list >output &&
+	git config --file "$WEIRDLY_NAMED_FILE" --show-origin --list >output &&
 	test_cmp expect output
 '
 
@@ -1747,7 +1752,7 @@ test_expect_success '--show-origin stdin with file include' '
 	test_cmp expect output
 '
 
-test_expect_success !MINGW '--show-origin blob' '
+test_expect_success '--show-origin blob' '
 	blob=$(git hash-object -w "$CUSTOM_CONFIG_FILE") &&
 	cat >expect <<-EOF &&
 	blob:$blob	user.custom=true
@@ -1756,9 +1761,9 @@ test_expect_success !MINGW '--show-origin blob' '
 	test_cmp expect output
 '
 
-test_expect_success !MINGW '--show-origin blob ref' '
+test_expect_success '--show-origin blob ref' '
 	cat >expect <<-\EOF &&
-	blob:"master:file\" (dq) and spaces.conf"	user.custom=true
+	blob:master:custom.conf	user.custom=true
 	EOF
 	git add "$CUSTOM_CONFIG_FILE" &&
 	git commit -m "new config file" &&