add -i: show progress counter in the prompt

Report the current hunk count and total number of hunks for the
current file in the prompt.  Also adjust the expected output in
some tests to match.

Signed-off-by: Kunal Tyagi <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: kunaltyagi

git-add--interactive.perl

@@ -1541,7 +1541,7 @@ sub patch_update_file {
 		for (@{$hunk[$ix]{DISPLAY}}) {
 			print;
 		}
-		print colored $prompt_color,
+		print colored $prompt_color, "(", ($ix+1), "/$num) ",
 			sprintf(__($patch_update_prompt_modes{$patch_mode}{$hunk[$ix]{TYPE}}), $other);
 
 		my $line = prompt_single_character;

t/t3701-add-interactive.sh

@@ -314,7 +314,7 @@ test_expect_success C_LOCALE_OUTPUT 'add first line works' '
 	git commit -am "clear local changes" &&
 	git apply patch &&
 	printf "%s\n" s y y | git add -p file 2>error |
-		sed -n -e "s/^Stage this hunk[^@]*\(@@ .*\)/\1/" \
+		sed -n -e "s/^([1-2]\/[1-2]) Stage this hunk[^@]*\(@@ .*\)/\1/" \
 		       -e "/^[-+@ \\\\]"/p  >output &&
 	test_must_be_empty error &&
 	git diff --cached >diff &&