Merge branch 'ld/p4-test-py3' into HEAD

The test scripts for "git p4" (but not "git p4" implementation
itself) has been updated so that they would work even on a system
where the installed version of Python is python 3.

* ld/p4-test-py3:
  git-p4 tests: time_in_seconds should use $PYTHON_PATH
  git-p4 tests: work with python3 as well as python2
  git-p4 tests: cd to / before running python

Author: gitster

t/lib-git-p4.sh

@@ -50,7 +50,7 @@ native_path() {
 # at runtime (e.g. via NTP). The 'clock_gettime(CLOCK_MONOTONIC)'
 # function could fix that but it is not in Python until 3.3.
 time_in_seconds() {
-	python -c 'import time; print int(time.time())'
+	(cd / && "$PYTHON_PATH" -c 'import time; print(int(time.time()))')
 }
 
 # Try to pick a unique port: guess a large number, then hope
@@ -198,9 +198,10 @@ marshal_dump() {
 	cat >"$TRASH_DIRECTORY/marshal-dump.py" <<-EOF &&
 	import marshal
 	import sys
+	instream = getattr(sys.stdin, 'buffer', sys.stdin)
 	for i in range($line):
-	    d = marshal.load(sys.stdin)
-	print d['$what']
+	    d = marshal.load(instream)
+	print(d[b'$what'].decode('utf-8'))
 	EOF
 	"$PYTHON_PATH" "$TRASH_DIRECTORY/marshal-dump.py"
 }

t/t9802-git-p4-filetype.sh

@@ -223,12 +223,12 @@ build_gendouble() {
 	import sys
 	import struct
 
-	s = struct.pack(">LL18s",
+	s = struct.pack(b">LL18s",
 			0x00051607,  # AppleDouble
 			0x00020000,  # version 2
-			""           # pad to 26 bytes
+			b""          # pad to 26 bytes
 	)
-	sys.stdout.write(s)
+	getattr(sys.stdout, 'buffer', sys.stdout).write(s)
 	EOF
 }