darcs-fast-import: add --symhack option

3 files changed, 46 insertions, 5 deletions

diff --git a/exporters/darcs/darcs-fast-import b/exporters/darcs/darcs-fast-import
index d190204..576c889 100755
--- a/exporters/darcs/darcs-fast-import
+++ b/exporters/darcs/darcs-fast-import
@@ -4,7 +4,7 @@
 
     darcs-fast-export - darcs backend for fast data exporters
 
-    Copyright (c) 2008 Miklos Vajna <vmiklos@frugalware.org>
+    Copyright (c) 2008, 2009, 2010 Miklos Vajna <vmiklos@frugalware.org>
     Copyright (c) 2008 Matthias Andree <matthias.andree@gmx.de>
 
     This program is free software; you can redistribute it and/or modify
@@ -168,6 +168,7 @@ class Handler:
 					self.files.append(path)
 		self.prevfiles = self.files[:]
 		adds = []
+		symlinks = []
 
 		self.read_next_line()
 		self.handle_mark()
@@ -205,13 +206,18 @@ class Handler:
 				self.invoke_add(dest)
 			elif self.line.startswith("M "):
 				items = self.line.split(' ')
-				if items[1] == "120000":
-					print "Adding symbolic links (symlinks) is not supported by Darcs."
-					sys.exit(2)
 				path = items[3][:-1]
 				dir = os.path.split(path)[0]
 				if len(dir) and not os.path.exists(dir):
 					os.makedirs(dir)
+				if items[1] == "120000":
+					if not self.options.symhack:
+						print "Adding symbolic links (symlinks) is not supported by Darcs."
+						sys.exit(2)
+					idx = int(items[2][1:]) # TODO: handle inline symlinks
+					symlinks.append((self.marks[idx], path))
+					self.read_next_line()
+					continue
 				sock = open(path, "w")
 				if items[2] != "inline":
 					idx = int(items[2][1:])
@@ -234,6 +240,16 @@ class Handler:
 
 		for i in adds:
 			self.invoke_add(i)
+		for src, path in symlinks:
+			# symlink does not do what we want if path is
+			# already there
+			if os.path.exists(path):
+				# rmtree() does not work on symlinks
+				if os.path.islink(path):
+					os.remove(path)
+				else:
+					shutil.rmtree(path)
+			os.symlink(src, path)
 		sock = subprocess.Popen(["darcs", "record", "--ignore-times", "-a", "--pipe"], stdin=subprocess.PIPE, stdout=subprocess.PIPE)
 		buf = [self.date, self.ident, self.short, self.long]
 		sock.stdin.write("\n".join(buf))
@@ -259,12 +275,15 @@ class Handler:
 		# Option Parser
 		usage="%prog [options]"
 		opp = optparse.OptionParser(usage=usage)
+		opp.set_defaults(symhack=False)
 		opp.add_option("--import-marks", metavar="IFILE",
 			help="read state for incremental imports from IFILE")
 		opp.add_option("--export-marks", metavar="OFILE",
 			help="write state for incremental imports to OFILE")
 		opp.add_option("--logfile", metavar="L",
 			help="log file which contains the output of external programs invoked during the conversion")
+		opp.add_option("--symhack", action="store_true", dest="symhack",
+			help="Do not error out when a symlink would be created, just create it in the workdir")
 		(self.options, args) = opp.parse_args()
 
 		if self.options.logfile:
diff --git a/exporters/darcs/darcs-fast-import.txt b/exporters/darcs/darcs-fast-import.txt
index 314b947..9e885bd 100644
--- a/exporters/darcs/darcs-fast-import.txt
+++ b/exporters/darcs/darcs-fast-import.txt
@@ -34,6 +34,14 @@ as well, via the --import-marks / --export-marks switches.
 	The output of external commands are redirected to a log file. You can
 	specify the path of that file with this parameter.
 
+--symhack::
+	Enable hack for symbolic links. darcs add does not handle them
+	but in case they are just added, we can create them in the working
+	directory. This can be handy in case for example the symbolic link is in
+	a subdirectory of the project and you don't even care about that
+	subdirectory. So the hack can be useful, but be extremely careful when
+	you use it.
+
 == EXIT CODES
 
 The exit code is:
diff --git a/exporters/darcs/t/testimport-gitsymlink.sh b/exporters/darcs/t/testimport-gitsymlink.sh
index 340a493..100c583 100644
--- a/exporters/darcs/t/testimport-gitsymlink.sh
+++ b/exporters/darcs/t/testimport-gitsymlink.sh
@@ -27,5 +27,19 @@ cd ..
 # we *do* want this to fail, but with error code 2. that means that we
 # detected that symlinks are not supported and the user does not get a
 # meaningless exception
-[ $? = 2 ]
+if [ $? != 2 ]; then
+	exit 1
+fi
+
+# now try with the symhack option
+rm -rf test.darcs
+mkdir test.darcs
+cd test.darcs
+darcs init
+cd ..
+(cd test; git fast-export --progress=2 HEAD) | (cd test.darcs; darcs-fast-import --symhack)
+if [ $? != 0 ]; then
+	exit 1
+fi
+diff_importgit test
 exit $?