Merge branch 'js/bisect-no-checkout'

* js/bisect-no-checkout:
  bisect: add support for bisecting bare repositories
  bisect: further style nitpicks
  bisect: replace "; then" with "\n<tab>*then"
  bisect: cleanup whitespace errors in git-bisect.sh.
  bisect: add documentation for --no-checkout option.
  bisect: add tests for the --no-checkout option.
  bisect: introduce --no-checkout support into porcelain.
  bisect: introduce support for --no-checkout option.
  bisect: add tests to document expected behaviour in presence of broken trees.
  bisect: use && to connect statements that are deferred with eval.
  bisect: move argument parsing before state modification.

1 files changed, 172 insertions, 3 deletions

diff --git a/t/t6030-bisect-porcelain.sh b/t/t6030-bisect-porcelain.sh
index b5063b6fe6..62125eca81 100755
--- a/t/t6030-bisect-porcelain.sh
+++ b/t/t6030-bisect-porcelain.sh
@@ -126,6 +126,18 @@ test_expect_success 'bisect reset removes packed refs' '
 	test -z "$(git for-each-ref "refs/heads/bisect")"
 '
 
+test_expect_success 'bisect reset removes bisect state after --no-checkout' '
+	git bisect reset &&
+	git bisect start --no-checkout &&
+	git bisect good $HASH1 &&
+	git bisect bad $HASH3 &&
+	git bisect next &&
+	git bisect reset &&
+	test -z "$(git for-each-ref "refs/bisect/*")" &&
+	test -z "$(git for-each-ref "refs/heads/bisect")" &&
+	test -z "$(git for-each-ref "BISECT_HEAD")"
+'
+
 test_expect_success 'bisect start: back in good branch' '
 	git branch > branch.output &&
 	grep "* other" branch.output > /dev/null &&
@@ -138,15 +150,23 @@ test_expect_success 'bisect start: back in good branch' '
 	grep "* other" branch.output > /dev/null
 '
 
-test_expect_success 'bisect start: no ".git/BISECT_START" if junk rev' '
-	git bisect start $HASH4 $HASH1 -- &&
-	git bisect good &&
+test_expect_success 'bisect start: no ".git/BISECT_START" created if junk rev' '
+	git bisect reset &&
 	test_must_fail git bisect start $HASH4 foo -- &&
 	git branch > branch.output &&
 	grep "* other" branch.output > /dev/null &&
 	test_must_fail test -e .git/BISECT_START
 '
 
+test_expect_success 'bisect start: existing ".git/BISECT_START" not modified if junk rev' '
+	git bisect start $HASH4 $HASH1 -- &&
+	git bisect good &&
+	cp .git/BISECT_START saved &&
+	test_must_fail git bisect start $HASH4 foo -- &&
+	git branch > branch.output &&
+	grep "* (no branch)" branch.output > /dev/null &&
+	test_cmp saved .git/BISECT_START
+'
 test_expect_success 'bisect start: no ".git/BISECT_START" if mistaken rev' '
 	git bisect start $HASH4 $HASH1 -- &&
 	git bisect good &&
@@ -572,6 +592,155 @@ test_expect_success 'erroring out when using bad path parameters' '
 	grep "bad path parameters" error.txt
 '
 
+test_expect_success 'test bisection on bare repo - --no-checkout specified' '
+	git clone --bare . bare.nocheckout &&
+	(
+		cd bare.nocheckout &&
+		git bisect start --no-checkout &&
+		git bisect good $HASH1 &&
+		git bisect bad $HASH4 &&
+		git bisect run eval \
+			"test \$(git rev-list BISECT_HEAD ^$HASH2 --max-count=1 | wc -l) = 0" \
+			>../nocheckout.log &&
+		git bisect reset
+	) &&
+	grep "$HASH3 is the first bad commit" nocheckout.log
+'
+
+
+test_expect_success 'test bisection on bare repo - --no-checkout defaulted' '
+	git clone --bare . bare.defaulted &&
+	(
+		cd bare.defaulted &&
+		git bisect start &&
+		git bisect good $HASH1 &&
+		git bisect bad $HASH4 &&
+		git bisect run eval \
+			"test \$(git rev-list BISECT_HEAD ^$HASH2 --max-count=1 | wc -l) = 0" \
+			>../defaulted.log &&
+		git bisect reset
+	) &&
+	grep "$HASH3 is the first bad commit" defaulted.log
+'
+
 #
+# This creates a broken branch which cannot be checked out because
+# the tree created has been deleted.
 #
+# H1-H2-H3-H4-H5-H6-H7  <--other
+#            \
+#             S5-S6'-S7'-S8'-S9  <--broken
+#
+# Commits marked with ' have a missing tree.
+#
+test_expect_success 'broken branch creation' '
+	git bisect reset &&
+	git checkout -b broken $HASH4 &&
+	git tag BROKEN_HASH4 $HASH4 &&
+	add_line_into_file "5(broken): first line on a broken branch" hello2 &&
+	git tag BROKEN_HASH5 &&
+	mkdir missing &&
+	:> missing/MISSING &&
+	git add missing/MISSING &&
+	git commit -m "6(broken): Added file that will be deleted"
+	git tag BROKEN_HASH6 &&
+	add_line_into_file "7(broken): second line on a broken branch" hello2 &&
+	git tag BROKEN_HASH7 &&
+	add_line_into_file "8(broken): third line on a broken branch" hello2 &&
+	git tag BROKEN_HASH8 &&
+	git rm missing/MISSING &&
+	git commit -m "9(broken): Remove missing file"
+	git tag BROKEN_HASH9 &&
+	rm .git/objects/39/f7e61a724187ab767d2e08442d9b6b9dab587d
+'
+
+echo "" > expected.ok
+cat > expected.missing-tree.default <<EOF
+fatal: unable to read tree 39f7e61a724187ab767d2e08442d9b6b9dab587d
+EOF
+
+test_expect_success 'bisect fails if tree is broken on start commit' '
+	git bisect reset &&
+	test_must_fail git bisect start BROKEN_HASH7 BROKEN_HASH4 2>error.txt &&
+	test_cmp expected.missing-tree.default error.txt
+'
+
+test_expect_success 'bisect fails if tree is broken on trial commit' '
+	git bisect reset &&
+	test_must_fail git bisect start BROKEN_HASH9 BROKEN_HASH4 2>error.txt &&
+	git reset --hard broken &&
+	git checkout broken &&
+	test_cmp expected.missing-tree.default error.txt
+'
+
+check_same()
+{
+	echo "Checking $1 is the same as $2" &&
+	git rev-parse "$1" > expected.same &&
+	git rev-parse "$2" > expected.actual &&
+	test_cmp expected.same expected.actual
+}
+
+test_expect_success 'bisect: --no-checkout - start commit bad' '
+	git bisect reset &&
+	git bisect start BROKEN_HASH7 BROKEN_HASH4 --no-checkout &&
+	check_same BROKEN_HASH6 BISECT_HEAD &&
+	git bisect reset
+'
+
+test_expect_success 'bisect: --no-checkout - trial commit bad' '
+	git bisect reset &&
+	git bisect start broken BROKEN_HASH4 --no-checkout &&
+	check_same BROKEN_HASH6 BISECT_HEAD &&
+	git bisect reset
+'
+
+test_expect_success 'bisect: --no-checkout - target before breakage' '
+	git bisect reset &&
+	git bisect start broken BROKEN_HASH4 --no-checkout &&
+	check_same BROKEN_HASH6 BISECT_HEAD &&
+	git bisect bad BISECT_HEAD &&
+	check_same BROKEN_HASH5 BISECT_HEAD &&
+	git bisect bad BISECT_HEAD &&
+	check_same BROKEN_HASH5 bisect/bad &&
+	git bisect reset
+'
+
+test_expect_success 'bisect: --no-checkout - target in breakage' '
+	git bisect reset &&
+	git bisect start broken BROKEN_HASH4 --no-checkout &&
+	check_same BROKEN_HASH6 BISECT_HEAD &&
+	git bisect bad BISECT_HEAD &&
+	check_same BROKEN_HASH5 BISECT_HEAD &&
+	git bisect good BISECT_HEAD &&
+	check_same BROKEN_HASH6 bisect/bad &&
+	git bisect reset
+'
+
+test_expect_success 'bisect: --no-checkout - target after breakage' '
+	git bisect reset &&
+	git bisect start broken BROKEN_HASH4 --no-checkout &&
+	check_same BROKEN_HASH6 BISECT_HEAD &&
+	git bisect good BISECT_HEAD &&
+	check_same BROKEN_HASH8 BISECT_HEAD &&
+	git bisect good BISECT_HEAD &&
+	check_same BROKEN_HASH9 bisect/bad &&
+	git bisect reset
+'
+
+test_expect_success 'bisect: demonstrate identification of damage boundary' "
+	git bisect reset &&
+	git checkout broken &&
+	git bisect start broken master --no-checkout &&
+	git bisect run sh -c '
+		GOOD=\$(git for-each-ref \"--format=%(objectname)\" refs/bisect/good-*) &&
+		git rev-list --objects BISECT_HEAD --not \$GOOD >tmp.\$\$ &&
+		git pack-objects --stdout >/dev/null < tmp.\$\$
+		rc=\$?
+		rm -f tmp.\$\$
+		test \$rc = 0' &&
+	check_same BROKEN_HASH6 bisect/bad &&
+	git bisect reset
+"
+
 test_done