[PATCH 03/11] git p4: work around p4 bug that causes empty symlinks

From

PWPete Wyckoff <pw@padd.com>

Date

Jan 21, 2014, 23:16 UTC

Message-ID

<1390346208-9207-4-git-send-email-pw@padd.com>

In-Reply-To

<1390346208-9207-1-git-send-email-pw@padd.com>

    //depot/empty-symlink - updating /home/me/p4/empty-symlink
    rename: /home/me/p4/empty-symlink: No such file or directory

and leaves no symlink.

Add a big test for all this too.

Tested-by: Damien Gérard <damien@iwi.me>
Signed-off-by: Pete Wyckoff <pw@padd.com>
---
 git-p4.py                  |  9 ++++++-
 t/t9802-git-p4-filetype.sh | 66 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 74 insertions(+), 1 deletion(-)

diff --git a/git-p4.py b/git-p4.py
index 5ea8bb8..e798ecf 100755
--- a/git-p4.py
+++ b/git-p4.py
@@ -2075,7 +2075,14 @@ class P4Sync(Command, P4UserMap):
             # p4 print on a symlink sometimes contains "target\n";
             # if it does, remove the newline
             data = ''.join(contents)
-            if data[-1] == '\n':
+            if not data:
+                # Some version of p4 allowed creating a symlink that pointed
+                # to nothing.  This causes p4 errors when checking out such
+                # a change, and errors here too.  Work around it by ignoring
+                # the bad symlink; hopefully a future change fixes it.
+                print "\nIgnoring empty symlink in %s" % file['depotFile']
+                return
+            elif data[-1] == '\n':
                 contents = [data[:-1]]
             else:
                 contents = [data]
diff --git a/t/t9802-git-p4-filetype.sh b/t/t9802-git-p4-filetype.sh
index 94d7be9..66d3fc9 100755
--- a/t/t9802-git-p4-filetype.sh
+++ b/t/t9802-git-p4-filetype.sh
@@ -267,6 +267,72 @@ test_expect_success SYMLINKS 'ensure p4 symlink parsed correctly' '
 	)
 '
 
+test_expect_success SYMLINKS 'empty symlink target' '
+	(
+		# first create the file as a file
+		cd "$cli" &&
+		>empty-symlink &&
+		p4 add empty-symlink &&
+		p4 submit -d "add empty-symlink as a file"
+	) &&
+	(
+		# now change it to be a symlink to "target1"
+		cd "$cli" &&
+		p4 edit empty-symlink &&
+		p4 reopen -t symlink empty-symlink &&
+		rm empty-symlink &&
+		ln -s target1 empty-symlink &&
+		p4 add empty-symlink &&
+		p4 submit -d "make empty-symlink point to target1"
+	) &&
+	(
+		# Hack the p4 depot to make the symlink point to nothing;
+		# this should not happen in reality, but shows up
+		# in p4 repos in the wild.
+		#
+		# The sed expression changes this:
+		#     @@
+		#     text
+		#     @target1
+		#     @
+		# to this:
+		#     @@
+		#     text
+		#     @@
+		#
+		cd "$db/depot" &&
+		sed "/@target1/{; s/target1/@/; n; d; }" \
+		    empty-symlink,v >empty-symlink,v.tmp &&
+		mv empty-symlink,v.tmp empty-symlink,v
+	) &&
+	(
+		# Make sure symlink really is empty.  Asking
+		# p4 to sync here will make it generate errors.
+		cd "$cli" &&
+		p4 print -q //depot/empty-symlink#2 >out &&
+		test ! -s out
+	) &&
+	test_when_finished cleanup_git &&
+
+	# make sure git p4 handles it without error
+	git p4 clone --dest="$git" //depot@all &&
+
+	# fix the symlink, make it point to "target2"
+	(
+		cd "$cli" &&
+		p4 open empty-symlink &&
+		rm empty-symlink &&
+		ln -s target2 empty-symlink &&
+		p4 submit -d "make empty-symlink point to target2"
+	) &&
+	cleanup_git &&
+	git p4 clone --dest="$git" //depot@all &&
+	(
+		cd "$git" &&
+		test $(readlink empty-symlink) = target2
+	)
+'
+
 test_expect_success 'kill p4d' '
 	kill_p4d
 '

-- 
1.8.5.2.320.g99957e5