git-p4: add diff/merge properties to .gitattributes for GitLFS files

The `git lfs track` command generates a .gitattributes file with diff
and merge properties [1]. Set the same .gitattributes format for files
tracked with GitLFS in git-p4.

[1] https://github.com/git-lfs/git-lfs/blob/v1.5.3/commands/command_track.go#L121

Signed-off-by: Lars Schneider <larsxschneider@gmail.com>
Reviewed-by: Luke Diamand <luke@diamand.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-p4.py

@@ -1098,10 +1098,10 @@ class GitLFS(LargeFileSystem):
                 '# Git LFS (see https://git-lfs.github.com/)\n',
                 '#\n',
             ] +
-            ['*.' + f.replace(' ', '[[:space:]]') + ' filter=lfs -text\n'
+            ['*.' + f.replace(' ', '[[:space:]]') + ' filter=lfs diff=lfs merge=lfs -text\n'
                 for f in sorted(gitConfigList('git-p4.largeFileExtensions'))
             ] +
-            ['/' + f.replace(' ', '[[:space:]]') + ' filter=lfs -text\n'
+            ['/' + f.replace(' ', '[[:space:]]') + ' filter=lfs diff=lfs merge=lfs -text\n'
                 for f in sorted(self.largeFiles) if not self.hasLargeFileExtension(f)
             ]
         )

t/t9824-git-p4-git-lfs.sh

@@ -81,9 +81,9 @@ test_expect_success 'Store files in LFS based on size (>24 bytes)' '
 		#
 		# Git LFS (see https://git-lfs.github.com/)
 		#
-		/file2.dat filter=lfs -text
-		/file4.bin filter=lfs -text
-		/path[[:space:]]with[[:space:]]spaces/file3.bin filter=lfs -text
+		/file2.dat filter=lfs diff=lfs merge=lfs -text
+		/file4.bin filter=lfs diff=lfs merge=lfs -text
+		/path[[:space:]]with[[:space:]]spaces/file3.bin filter=lfs diff=lfs merge=lfs -text
 		EOF
 		test_path_is_file .gitattributes &&
 		test_cmp expect .gitattributes
@@ -109,7 +109,7 @@ test_expect_success 'Store files in LFS based on size (>25 bytes)' '
 		#
 		# Git LFS (see https://git-lfs.github.com/)
 		#
-		/file4.bin filter=lfs -text
+		/file4.bin filter=lfs diff=lfs merge=lfs -text
 		EOF
 		test_path_is_file .gitattributes &&
 		test_cmp expect .gitattributes
@@ -135,7 +135,7 @@ test_expect_success 'Store files in LFS based on extension (dat)' '
 		#
 		# Git LFS (see https://git-lfs.github.com/)
 		#
-		*.dat filter=lfs -text
+		*.dat filter=lfs diff=lfs merge=lfs -text
 		EOF
 		test_path_is_file .gitattributes &&
 		test_cmp expect .gitattributes
@@ -163,8 +163,8 @@ test_expect_success 'Store files in LFS based on size (>25 bytes) and extension
 		#
 		# Git LFS (see https://git-lfs.github.com/)
 		#
-		*.dat filter=lfs -text
-		/file4.bin filter=lfs -text
+		*.dat filter=lfs diff=lfs merge=lfs -text
+		/file4.bin filter=lfs diff=lfs merge=lfs -text
 		EOF
 		test_path_is_file .gitattributes &&
 		test_cmp expect .gitattributes
@@ -199,8 +199,8 @@ test_expect_success 'Remove file from repo and store files in LFS based on size
 		#
 		# Git LFS (see https://git-lfs.github.com/)
 		#
-		/file2.dat filter=lfs -text
-		/path[[:space:]]with[[:space:]]spaces/file3.bin filter=lfs -text
+		/file2.dat filter=lfs diff=lfs merge=lfs -text
+		/path[[:space:]]with[[:space:]]spaces/file3.bin filter=lfs diff=lfs merge=lfs -text
 		EOF
 		test_path_is_file .gitattributes &&
 		test_cmp expect .gitattributes
@@ -237,8 +237,8 @@ test_expect_success 'Add .gitattributes and store files in LFS based on size (>2
 		#
 		# Git LFS (see https://git-lfs.github.com/)
 		#
-		/file2.dat filter=lfs -text
-		/path[[:space:]]with[[:space:]]spaces/file3.bin filter=lfs -text
+		/file2.dat filter=lfs diff=lfs merge=lfs -text
+		/path[[:space:]]with[[:space:]]spaces/file3.bin filter=lfs diff=lfs merge=lfs -text
 		EOF
 		test_path_is_file .gitattributes &&
 		test_cmp expect .gitattributes
@@ -278,7 +278,7 @@ test_expect_success 'Add big files to repo and store files in LFS based on compr
 		#
 		# Git LFS (see https://git-lfs.github.com/)
 		#
-		/file6.bin filter=lfs -text
+		/file6.bin filter=lfs diff=lfs merge=lfs -text
 		EOF
 		test_path_is_file .gitattributes &&
 		test_cmp expect .gitattributes