config: change default of pager.config to "on"

This is similar to ff1e724 (tag: change default of `pager.tag` to
"on", 2017-08-02) and is safe now that we do not consider `pager.config`
at all when we are not listing or getting configuration. This change
will help with listing large configurations, but will not hurt users of
`git config --edit` as it would have before the previous commit.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: Martin Ågren

Documentation/git-config.txt

@@ -237,6 +237,7 @@ CONFIGURATION
 -------------
 `pager.config` is only respected when listing configuration, i.e., when
 using `--list` or any of the `--get-*` which may return multiple results.
+The default is to use a pager.
 
 [[FILES]]
 FILES

builtin/config.c

@@ -602,7 +602,7 @@ int cmd_config(int argc, const char **argv, const char *prefix)
 	}
 
 	if (actions & PAGING_ACTIONS)
-		setup_auto_pager("config", 0);
+		setup_auto_pager("config", 1);
 
 	if (actions == ACTION_LIST) {
 		check_argc(argc, 0, 0);

t/t7006-pager.sh

@@ -267,23 +267,23 @@ test_expect_success TTY 'git config --get ignores pager.config' '
 	! test -e paginated.out
 '
 
-test_expect_success TTY 'git config --get-urlmatch defaults to not paging' '
+test_expect_success TTY 'git config --get-urlmatch defaults to paging' '
 	rm -f paginated.out &&
 	test_terminal git -c http."https://foo.com/".bar=foo \
 			  config --get-urlmatch http https://foo.com &&
-	! test -e paginated.out
+	test -e paginated.out
 '
 
 test_expect_success TTY 'git config --get-all respects pager.config' '
 	rm -f paginated.out &&
-	test_terminal git -c pager.config config --get-all foo.bar &&
-	test -e paginated.out
+	test_terminal git -c pager.config=false config --get-all foo.bar &&
+	! test -e paginated.out
 '
 
-test_expect_success TTY 'git config --list defaults to not paging' '
+test_expect_success TTY 'git config --list defaults to paging' '
 	rm -f paginated.out &&
 	test_terminal git config --list &&
-	! test -e paginated.out
+	test -e paginated.out
 '