compression: unify pack.compression configuration parsing

There are three codepaths that use a variable whose name is
pack_compression_level to affect how objects and deltas sent to a
packfile is compressed.  Unlike zlib_compression_level that controls
the loose object compression, however, this variable was static to
each of these codepaths.  Two of them read the pack.compression
configuration variable, using core.compression as the default, and
one of them also allowed overriding it from the command line.

The other codepath in bulk-checkin did not pay any attention to the
configuration.

Unify the configuration parsing to git_default_config(), where we
implement the parsing of core.loosecompression and core.compression
and make the former override the latter, by moving code to parse
pack.compression and also allow core.compression to give default to
this variable.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

3 files changed, 140 insertions, 0 deletions

diff --git a/t/t1050-large.sh b/t/t1050-large.sh
index 096dbffecc..6fd264cff0 100755
--- a/t/t1050-large.sh
+++ b/t/t1050-large.sh
@@ -5,6 +5,12 @@ test_description='adding and checking out large blobs'
 
 . ./test-lib.sh
 
+# This should be moved to test-lib.sh together with the
+# copy in t0021 after both topics have graduated to 'master'.
+file_size () {
+	perl -e 'print -s $ARGV[0]' "$1"
+}
+
 test_expect_success setup '
 	# clone does not allow us to pass core.bigfilethreshold to
 	# new repos, so set core.bigfilethreshold globally
@@ -17,6 +23,29 @@ test_expect_success setup '
 	export GIT_ALLOC_LIMIT
 '
 
+# add a large file with different settings
+while read expect config
+do
+	test_expect_success "add with $config" '
+		test_when_finished "rm -f .git/objects/pack/pack-*.* .git/index" &&
+		git $config add large1 &&
+		sz=$(file_size .git/objects/pack/pack-*.pack) &&
+		case "$expect" in
+		small) test "$sz" -le 100000 ;;
+		large) test "$sz" -ge 100000 ;;
+		esac
+	'
+done <<\EOF
+large -c core.compression=0
+small -c core.compression=9
+large -c core.compression=0 -c pack.compression=0
+large -c core.compression=9 -c pack.compression=0
+small -c core.compression=0 -c pack.compression=9
+small -c core.compression=9 -c pack.compression=9
+large -c pack.compression=0
+small -c pack.compression=9
+EOF
+
 test_expect_success 'add a large file or two' '
 	git add large1 huge large2 &&
 	# make sure we got a single packfile and no loose objects
diff --git a/t/t5315-pack-objects-compression.sh b/t/t5315-pack-objects-compression.sh
new file mode 100755
index 0000000000..34c47dae09
--- /dev/null
+++ b/t/t5315-pack-objects-compression.sh
@@ -0,0 +1,44 @@
+#!/bin/sh
+
+test_description='pack-object compression configuration'
+
+. ./test-lib.sh
+
+# This should be moved to test-lib.sh together with the
+# copy in t0021 after both topics have graduated to 'master'.
+file_size () {
+	perl -e 'print -s $ARGV[0]' "$1"
+}
+
+test_expect_success setup '
+	printf "%2000000s" X |
+	git hash-object -w --stdin >object-name &&
+	# make sure it resulted in a loose object
+	ob=$(sed -e "s/\(..\).*/\1/" object-name) &&
+	ject=$(sed -e "s/..\(.*\)/\1/" object-name) &&
+	test -f .git/objects/$ob/$ject
+'
+
+while read expect config
+do
+	test_expect_success "pack-objects with $config" '
+		test_when_finished "rm -f pack-*.*" &&
+		git $config pack-objects pack <object-name &&
+		sz=$(file_size pack-*.pack) &&
+		case "$expect" in
+		small) test "$sz" -le 100000 ;;
+		large) test "$sz" -ge 100000 ;;
+		esac
+	'
+done <<\EOF
+large -c core.compression=0
+small -c core.compression=9
+large -c core.compression=0 -c pack.compression=0
+large -c core.compression=9 -c pack.compression=0
+small -c core.compression=0 -c pack.compression=9
+small -c core.compression=9 -c pack.compression=9
+large -c pack.compression=0
+small -c pack.compression=9
+EOF
+
+test_done
diff --git a/t/t9303-fast-import-compression.sh b/t/t9303-fast-import-compression.sh
new file mode 100755
index 0000000000..856219f46a
--- /dev/null
+++ b/t/t9303-fast-import-compression.sh
@@ -0,0 +1,67 @@
+#!/bin/sh
+
+test_description='compression setting of fast-import utility'
+. ./test-lib.sh
+
+# This should be moved to test-lib.sh together with the
+# copy in t0021 after both topics have graduated to 'master'.
+file_size () {
+	perl -e 'print -s $ARGV[0]' "$1"
+}
+
+import_large () {
+	(
+		echo blob
+		echo "data <<EOD"
+		printf "%2000000s\n" "$*"
+		echo EOD
+	) | git "$@" fast-import
+}
+
+while read expect config
+do
+	test_expect_success "fast-import (packed) with $config" '
+		test_when_finished "rm -f .git/objects/pack/pack-*.*" &&
+		test_when_finished "rm -rf .git/objects/??" &&
+		import_large -c fastimport.unpacklimit=0 $config &&
+		sz=$(file_size .git/objects/pack/pack-*.pack) &&
+		case "$expect" in
+		small) test "$sz" -le 100000 ;;
+		large) test "$sz" -ge 100000 ;;
+		esac
+	'
+done <<\EOF
+large -c core.compression=0
+small -c core.compression=9
+large -c core.compression=0 -c pack.compression=0
+large -c core.compression=9 -c pack.compression=0
+small -c core.compression=0 -c pack.compression=9
+small -c core.compression=9 -c pack.compression=9
+large -c pack.compression=0
+small -c pack.compression=9
+EOF
+
+while read expect config
+do
+	test_expect_success "fast-import (loose) with $config" '
+		test_when_finished "rm -f .git/objects/pack/pack-*.*" &&
+		test_when_finished "rm -rf .git/objects/??" &&
+		import_large -c fastimport.unpacklimit=9 $config &&
+		sz=$(file_size .git/objects/??/????*) &&
+		case "$expect" in
+		small) test "$sz" -le 100000 ;;
+		large) test "$sz" -ge 100000 ;;
+		esac
+	'
+done <<\EOF
+large -c core.compression=0
+small -c core.compression=9
+large -c core.compression=0 -c core.loosecompression=0
+large -c core.compression=9 -c core.loosecompression=0
+small -c core.compression=0 -c core.loosecompression=9
+small -c core.compression=9 -c core.loosecompression=9
+large -c core.loosecompression=0
+small -c core.loosecompression=9
+EOF
+
+test_done