Re: [PATCH] fast-import: checkpoint: dump branches/tags/marks even if object_count==0

["Eric Rannaud" <e@nanocritical.com>]

On Thu, Sep 28, 2017 at 5:59 AM, Adam Dinwoodie <adam@dinwoodie.org> wrote:
> On Wed, Sep 27, 2017 at 10:07:41PM -0700, Eric Rannaud wrote:
>>
>> Also adding the necessary PIPE prereq, as pointed out by Ramsay Jones.
>
> Cygwin doesn't have the PIPE prereq; I've just confirmed that the
> previous version of this patch has t9300 failing on Cygwin, but this
> version passes.

What's the preferred solution here? I can avoid using named pipes entirely:

	read_checkpoint () {
		if read output
		then
			if ! test "$output" = "progress checkpoint"
			then
				echo >&2 "no progress checkpoint received: $output"
				echo 1 > V.result
			else
				echo 0 > V.result
			fi
		else
			echo >&2 "failed to read fast-import output"
			echo 1 > V.result
		fi
	}
	
	# The commands in input_file should not produce any output on the file
	# descriptor set with --cat-blob-fd (or stdout if unspecified).
	#
	# To make sure you're observing the side effects of checkpoint *before*
	# fast-import terminates (and thus writes out its state), check that the
	# fast-import process is still running using background_import_still_running
	# *after* evaluating the test conditions.
	background_import_then_checkpoint () {
		options=$1
		input_file=$2
	
		rm -f V.result
	
		( cat "$input_file"
		echo "checkpoint"
		echo "progress checkpoint"
		sleep 3600 &
		echo $! >V.pid
		wait ) | git fast-import $options | read_checkpoint &
	
		# We don't mind if the pipeline has already died by the time the test
		# ends.
		test_when_finished "kill $(cat V.pid) || true"
	
		while ! test -f V.result
		do
			# Try to sleep less than a second, if supported.
			sleep .1 2>/dev/null || sleep 1
		done
		return $(cat V.result)
	}

Do we like this better?