Merge branch 'ab/fsck-unexpected-type'

"git fsck" has been taught to report mismatch between expected and
actual types of an object better.

* ab/fsck-unexpected-type:
  fsck: report invalid object type-path combinations
  fsck: don't hard die on invalid object types
  object-file.c: stop dying in parse_loose_header()
  object-file.c: return ULHR_TOO_LONG on "header too long"
  object-file.c: use "enum" return type for unpack_loose_header()
  object-file.c: simplify unpack_loose_short_header()
  object-file.c: make parse_loose_header_extended() public
  object-file.c: return -1, not "status" from unpack_loose_header()
  object-file.c: don't set "typep" when returning non-zero
  cat-file tests: test for current --allow-unknown-type behavior
  cat-file tests: add corrupt loose object test
  cat-file tests: test for missing/bogus object with -t, -s and -p
  cat-file tests: move bogus_* variable declarations earlier
  fsck tests: test for garbage appended to a loose object
  fsck tests: test current hash/type mismatch behavior
  fsck tests: refactor one test to use a sub-repo
  fsck tests: add test for fsck-ing an unknown type

1 files changed, 209 insertions, 19 deletions

diff --git a/t/t1006-cat-file.sh b/t/t1006-cat-file.sh
index 4a753705ec..658628375c 100755
--- a/t/t1006-cat-file.sh
+++ b/t/t1006-cat-file.sh
@@ -315,46 +315,236 @@ test_expect_success '%(deltabase) reports packed delta bases' '
 	}
 '
 
-bogus_type="bogus"
-bogus_content="bogus"
-bogus_size=$(strlen "$bogus_content")
-bogus_sha1=$(echo_without_newline "$bogus_content" | git hash-object -t $bogus_type --literally -w --stdin)
+test_expect_success 'setup bogus data' '
+	bogus_short_type="bogus" &&
+	bogus_short_content="bogus" &&
+	bogus_short_size=$(strlen "$bogus_short_content") &&
+	bogus_short_sha1=$(echo_without_newline "$bogus_short_content" | git hash-object -t $bogus_short_type --literally -w --stdin) &&
+
+	bogus_long_type="abcdefghijklmnopqrstuvwxyz1234679" &&
+	bogus_long_content="bogus" &&
+	bogus_long_size=$(strlen "$bogus_long_content") &&
+	bogus_long_sha1=$(echo_without_newline "$bogus_long_content" | git hash-object -t $bogus_long_type --literally -w --stdin)
+'
+
+for arg1 in '' --allow-unknown-type
+do
+	for arg2 in -s -t -p
+	do
+		if test "$arg1" = "--allow-unknown-type" && test "$arg2" = "-p"
+		then
+			continue
+		fi
+
+
+		test_expect_success "cat-file $arg1 $arg2 error on bogus short OID" '
+			cat >expect <<-\EOF &&
+			fatal: invalid object type
+			EOF
+
+			if test "$arg1" = "--allow-unknown-type"
+			then
+				git cat-file $arg1 $arg2 $bogus_short_sha1
+			else
+				test_must_fail git cat-file $arg1 $arg2 $bogus_short_sha1 >out 2>actual &&
+				test_must_be_empty out &&
+				test_cmp expect actual
+			fi
+		'
+
+		test_expect_success "cat-file $arg1 $arg2 error on bogus full OID" '
+			if test "$arg2" = "-p"
+			then
+				cat >expect <<-EOF
+				error: header for $bogus_long_sha1 too long, exceeds 32 bytes
+				fatal: Not a valid object name $bogus_long_sha1
+				EOF
+			else
+				cat >expect <<-EOF
+				error: header for $bogus_long_sha1 too long, exceeds 32 bytes
+				fatal: git cat-file: could not get object info
+				EOF
+			fi &&
+
+			if test "$arg1" = "--allow-unknown-type"
+			then
+				git cat-file $arg1 $arg2 $bogus_short_sha1
+			else
+				test_must_fail git cat-file $arg1 $arg2 $bogus_long_sha1 >out 2>actual &&
+				test_must_be_empty out &&
+				test_cmp expect actual
+			fi
+		'
+
+		test_expect_success "cat-file $arg1 $arg2 error on missing short OID" '
+			cat >expect.err <<-EOF &&
+			fatal: Not a valid object name $(test_oid deadbeef_short)
+			EOF
+			test_must_fail git cat-file $arg1 $arg2 $(test_oid deadbeef_short) >out 2>err.actual &&
+			test_must_be_empty out
+		'
+
+		test_expect_success "cat-file $arg1 $arg2 error on missing full OID" '
+			if test "$arg2" = "-p"
+			then
+				cat >expect.err <<-EOF
+				fatal: Not a valid object name $(test_oid deadbeef)
+				EOF
+			else
+				cat >expect.err <<-\EOF
+				fatal: git cat-file: could not get object info
+				EOF
+			fi &&
+			test_must_fail git cat-file $arg1 $arg2 $(test_oid deadbeef) >out 2>err.actual &&
+			test_must_be_empty out &&
+			test_cmp expect.err err.actual
+		'
+	done
+done
+
+test_expect_success '-e is OK with a broken object without --allow-unknown-type' '
+	git cat-file -e $bogus_short_sha1
+'
+
+test_expect_success '-e can not be combined with --allow-unknown-type' '
+	test_expect_code 128 git cat-file -e --allow-unknown-type $bogus_short_sha1
+'
+
+test_expect_success '-p cannot print a broken object even with --allow-unknown-type' '
+	test_must_fail git cat-file -p $bogus_short_sha1 &&
+	test_expect_code 128 git cat-file -p --allow-unknown-type $bogus_short_sha1
+'
+
+test_expect_success '<type> <hash> does not work with objects of broken types' '
+	cat >err.expect <<-\EOF &&
+	fatal: invalid object type "bogus"
+	EOF
+	test_must_fail git cat-file $bogus_short_type $bogus_short_sha1 2>err.actual &&
+	test_cmp err.expect err.actual
+'
+
+test_expect_success 'broken types combined with --batch and --batch-check' '
+	echo $bogus_short_sha1 >bogus-oid &&
+
+	cat >err.expect <<-\EOF &&
+	fatal: invalid object type
+	EOF
+
+	test_must_fail git cat-file --batch <bogus-oid 2>err.actual &&
+	test_cmp err.expect err.actual &&
+
+	test_must_fail git cat-file --batch-check <bogus-oid 2>err.actual &&
+	test_cmp err.expect err.actual
+'
+
+test_expect_success 'the --batch and --batch-check options do not combine with --allow-unknown-type' '
+	test_expect_code 128 git cat-file --batch --allow-unknown-type <bogus-oid &&
+	test_expect_code 128 git cat-file --batch-check --allow-unknown-type <bogus-oid
+'
+
+test_expect_success 'the --allow-unknown-type option does not consider replacement refs' '
+	cat >expect <<-EOF &&
+	$bogus_short_type
+	EOF
+	git cat-file -t --allow-unknown-type $bogus_short_sha1 >actual &&
+	test_cmp expect actual &&
+
+	# Create it manually, as "git replace" will die on bogus
+	# types.
+	head=$(git rev-parse --verify HEAD) &&
+	test_when_finished "rm -rf .git/refs/replace" &&
+	mkdir -p .git/refs/replace &&
+	echo $head >.git/refs/replace/$bogus_short_sha1 &&
+
+	cat >expect <<-EOF &&
+	commit
+	EOF
+	git cat-file -t --allow-unknown-type $bogus_short_sha1 >actual &&
+	test_cmp expect actual
+'
 
 test_expect_success "Type of broken object is correct" '
-	echo $bogus_type >expect &&
-	git cat-file -t --allow-unknown-type $bogus_sha1 >actual &&
+	echo $bogus_short_type >expect &&
+	git cat-file -t --allow-unknown-type $bogus_short_sha1 >actual &&
 	test_cmp expect actual
 '
 
 test_expect_success "Size of broken object is correct" '
-	echo $bogus_size >expect &&
-	git cat-file -s --allow-unknown-type $bogus_sha1 >actual &&
+	echo $bogus_short_size >expect &&
+	git cat-file -s --allow-unknown-type $bogus_short_sha1 >actual &&
 	test_cmp expect actual
 '
 
 test_expect_success 'clean up broken object' '
-	rm .git/objects/$(test_oid_to_path $bogus_sha1)
+	rm .git/objects/$(test_oid_to_path $bogus_short_sha1)
 '
 
-bogus_type="abcdefghijklmnopqrstuvwxyz1234679"
-bogus_content="bogus"
-bogus_size=$(strlen "$bogus_content")
-bogus_sha1=$(echo_without_newline "$bogus_content" | git hash-object -t $bogus_type --literally -w --stdin)
-
 test_expect_success "Type of broken object is correct when type is large" '
-	echo $bogus_type >expect &&
-	git cat-file -t --allow-unknown-type $bogus_sha1 >actual &&
+	echo $bogus_long_type >expect &&
+	git cat-file -t --allow-unknown-type $bogus_long_sha1 >actual &&
 	test_cmp expect actual
 '
 
 test_expect_success "Size of large broken object is correct when type is large" '
-	echo $bogus_size >expect &&
-	git cat-file -s --allow-unknown-type $bogus_sha1 >actual &&
+	echo $bogus_long_size >expect &&
+	git cat-file -s --allow-unknown-type $bogus_long_sha1 >actual &&
 	test_cmp expect actual
 '
 
 test_expect_success 'clean up broken object' '
-	rm .git/objects/$(test_oid_to_path $bogus_sha1)
+	rm .git/objects/$(test_oid_to_path $bogus_long_sha1)
+'
+
+test_expect_success 'cat-file -t and -s on corrupt loose object' '
+	git init --bare corrupt-loose.git &&
+	(
+		cd corrupt-loose.git &&
+
+		# Setup and create the empty blob and its path
+		empty_path=$(git rev-parse --git-path objects/$(test_oid_to_path "$EMPTY_BLOB")) &&
+		git hash-object -w --stdin </dev/null &&
+
+		# Create another blob and its path
+		echo other >other.blob &&
+		other_blob=$(git hash-object -w --stdin <other.blob) &&
+		other_path=$(git rev-parse --git-path objects/$(test_oid_to_path "$other_blob")) &&
+
+		# Before the swap the size is 0
+		cat >out.expect <<-EOF &&
+		0
+		EOF
+		git cat-file -s "$EMPTY_BLOB" >out.actual 2>err.actual &&
+		test_must_be_empty err.actual &&
+		test_cmp out.expect out.actual &&
+
+		# Swap the two to corrupt the repository
+		mv -f "$other_path" "$empty_path" &&
+		test_must_fail git fsck 2>err.fsck &&
+		grep "hash-path mismatch" err.fsck &&
+
+		# confirm that cat-file is reading the new swapped-in
+		# blob...
+		cat >out.expect <<-EOF &&
+		blob
+		EOF
+		git cat-file -t "$EMPTY_BLOB" >out.actual 2>err.actual &&
+		test_must_be_empty err.actual &&
+		test_cmp out.expect out.actual &&
+
+		# ... since it has a different size now.
+		cat >out.expect <<-EOF &&
+		6
+		EOF
+		git cat-file -s "$EMPTY_BLOB" >out.actual 2>err.actual &&
+		test_must_be_empty err.actual &&
+		test_cmp out.expect out.actual &&
+
+		# So far "cat-file" has been happy to spew the found
+		# content out as-is. Try to make it zlib-invalid.
+		mv -f other.blob "$empty_path" &&
+		test_must_fail git fsck 2>err.fsck &&
+		grep "^error: inflate: data stream error (" err.fsck
+	)
 '
 
 # Tests for git cat-file --follow-symlinks