darcs2hg: Now understands files that were explicitly renamed in darcs.

contrib/darcs2hg.py

@@ -1,179 +1,229
 #!/usr/bin/env python
 # Encoding: iso-8859-1
 # vim: tw=80 ts=4 sw=4 noet
 # -----------------------------------------------------------------------------
 # Project   : Basic Darcs to Mercurial conversion script
 # -----------------------------------------------------------------------------
 # Authors   : Sebastien Pierre                           <[e-mail]>
 #             TK Soh                                      <[e-mail]>
 # -----------------------------------------------------------------------------
 # Creation  : 24-May-2006
 # Last mod  : 05-Jun-2006
 # -----------------------------------------------------------------------------
 
 import os, sys
 import tempfile
 import xml.dom.minidom as xml_dom
 from time import strptime, mktime
 
 DARCS_REPO = None
 HG_REPO    = None
 
 USAGE = """\
 %s DARCSREPO HGREPO [SKIP]
 
     Converts the given Darcs repository to a new Mercurial repository. The given
     HGREPO must not exist, as it will be created and filled up (this will avoid
     overwriting valuable data.
 
     In case an error occurs within the process, you can resume the process by
     giving the last successfuly applied change number.
 """ % (os.path.basename(sys.argv[0]))
 
 # ------------------------------------------------------------------------------
 #
 # Utilities
 #
 # ------------------------------------------------------------------------------
 
 def cmd(text, path=None, silent=False):
 	"""Executes a command, in the given directory (if any), and returns the
 	command result as a string."""
 	cwd = None
 	if path:
 		path = os.path.abspath(path)
 		cwd  = os.getcwd()
 		os.chdir(path)
 	if not silent: print "> ", text
 	res = os.popen(text).read()
 	if path:
 		os.chdir(cwd)
 	return res
 
 def writefile(path, data):
 	"""Writes the given data into the given file."""
 	f = file(path, "w") ; f.write(data)  ; f.close()
 
 def error( *args ):
 	sys.stderr.write("ERROR: ")
 	for a in args: sys.stderr.write(str(a))
 	sys.stderr.write("\n")
 	sys.stderr.write("You can make manual fixes if necessary and then resume by"
 	" giving the last changeset number")
 	sys.exit(-1)
 
 # ------------------------------------------------------------------------------
 #
 # Darcs interface
 #
 # ------------------------------------------------------------------------------
 
 def darcs_changes(darcsRepo):
 	"""Gets the changes list from the given darcs repository. This returns the
 	chronological list of changes as (change name, change summary)."""
 	changes    = cmd("darcs changes --reverse --xml-output", darcsRepo)
 	doc        = xml_dom.parseString(changes)
 	for patch_node in doc.childNodes[0].childNodes:
 		name = filter(lambda n: n.nodeName == "name", patch_node.childNodes)
 		comm = filter(lambda n: n.nodeName == "comment", patch_node.childNodes)
 		if not name:continue
 		else: name = name[0].childNodes[0].data
 		if not comm: comm = ""
 		else: comm = comm[0].childNodes[0].data
 		author = patch_node.getAttribute("author")
 		date   = patch_node.getAttribute("date")
 		chash  = os.path.splitext(patch_node.getAttribute("hash"))[0]
 		yield author, date, name, chash, comm
 
 def darcs_tip(darcs_repo):
 	changes = cmd("darcs changes",darcs_repo,silent=True)
 	changes = filter(lambda l: l.strip().startswith("* "), changes.split("\n"))
 	return len(changes)
 
 def darcs_pull(hg_repo, darcs_repo, chash):
 	old_tip = darcs_tip(darcs_repo)
 	res     = cmd("darcs pull \"%s\" --all --match=\"hash %s\"" % (darcs_repo, chash), hg_repo)
 	print res
 	new_tip = darcs_tip(darcs_repo)
 	if not new_tip != old_tip + 1:
 		error("Darcs pull did not work as expected: " + res)
 
+def darcs_changes_summary(darcs_repo, chash):
+	"""Gets the changes from the darcs summary. This returns the chronological
+	list of changes as (change_type, args). Eg. ('add_file', 'foo.txt') or
+	('move', ['foo.txt','bar.txt'])."""
+	change = cmd("darcs changes --summary --xml-output --match=\"hash %s\"" % (chash), darcs_repo)
+	doc = xml_dom.parseString(change)
+	for patch_node in doc.childNodes[0].childNodes:
+		summary_nodes = filter(lambda n: n.nodeName == "summary" and n.nodeType == n.ELEMENT_NODE, patch_node.childNodes)
+		for summary_node in summary_nodes:
+			change_nodes = filter(lambda n: n.nodeType == n.ELEMENT_NODE, summary_node.childNodes)
+			for change_node in change_nodes:
+				change = change_node.nodeName
+				if change == 'modify_file':
+					yield change, change_node.childNodes[0].data.strip()
+				elif change == 'add_file':
+					yield change, change_node.childNodes[0].data.strip()
+				elif change == 'remove_file':
+					yield change, change_node.childNodes[0].data.strip()
+				elif change == 'add_directory':
+					yield change, change_node.childNodes[0].data.strip()
+				elif change == 'remove_directory':
+					yield change, change_node.childNodes[0].data.strip()
+				elif change == 'move':
+					yield change, (change_node.getAttribute('from'), change_node.getAttribute('to'))
+				else:
+					error('Problem parsing summary xml: Unexpected element: ' + change_node.toxml())
+
 # ------------------------------------------------------------------------------
 #
 # Mercurial interface
 #
 # ------------------------------------------------------------------------------
 
 def hg_commit( hg_repo, text, author, date ):
 	fd, tmpfile = tempfile.mkstemp(prefix="darcs2hg_")
 	writefile(tmpfile, text)
 	old_tip = hg_tip(hg_repo)
 	cmd("hg add -X _darcs", hg_repo)
 	cmd("hg remove -X _darcs --after", hg_repo)
 	res = cmd("hg commit -l %s -u \"%s\" -d \"%s 0\""  % (tmpfile, author, date), hg_repo)
 	os.close(fd)
 	os.unlink(tmpfile)
 	new_tip = hg_tip(hg_repo)
 	if not new_tip == old_tip + 1:
 		# Sometimes we may have empty commits, we simply skip them
 		if res.strip().lower().find("nothing changed") != -1:
 			pass
 		else:
 			error("Mercurial commit did not work as expected: " + res)
 
 def hg_tip( hg_repo ):
 	"""Returns the latest local revision number in the given repository."""
 	tip = cmd("hg tip", hg_repo, silent=True)
 	tip = tip.split("\n")[0].split(":")[1].strip()
 	return int(tip)
 
+def hg_rename( hg_repo, from_file, to_file ):
+	cmd("hg rename --after \"%s\" \"%s\"" % (from_file, to_file), hg_repo);
+	
+def hg_handle_change( hg_repo, change, arg ):
+	"""Processes a change event as output by darcs_changes_summary. These
+	consist of file move/rename/add/delete commands."""
+	if change == 'modify_file':
+		pass
+	elif change == 'add_file':
+		pass
+	elif change =='remove_file':
+		pass
+	elif change == 'add_directory':
+		pass
+	elif change == 'remove_directory':
+		pass
+	elif change == 'move':
+		hg_rename(hg_repo, arg[0], arg[1])
+	else:
+		error('Unknown change type ' + change + ': ' + arg)
+
 # ------------------------------------------------------------------------------
 #
 # Main
 #
 # ------------------------------------------------------------------------------
 
 if __name__ == "__main__":
 	args = sys.argv[1:]
 	# We parse the arguments
 	if len(args)   == 2:
 		darcs_repo = os.path.abspath(args[0])
 		hg_repo    = os.path.abspath(args[1])
 		skip       = None
 	elif len(args) == 3:
 		darcs_repo = os.path.abspath(args[0])
 		hg_repo    = os.path.abspath(args[1])
 		skip       = int(args[2])
 	else:
 		print USAGE
 		sys.exit(-1)
 	# Initializes the target repo
 	if not os.path.isdir(darcs_repo + "/_darcs"):
 		print "No darcs directory found at: " + darcs_repo
 		sys.exit(-1)
 	if not os.path.isdir(hg_repo):
 		os.mkdir(hg_repo)
 	elif skip == None:
 		print "Given HG repository must not exist when no SKIP is specified."
 		sys.exit(-1)
 	if skip == None:
 		cmd("hg init \"%s\"" % (hg_repo))
 		cmd("darcs initialize", hg_repo)
 	# Get the changes from the Darcs repository
 	change_number = 0
 	for author, date, summary, chash, description in darcs_changes(darcs_repo):
 		print "== changeset", change_number,
 		if skip != None and change_number <= skip:
 			print "(skipping)"
 		else:
 			text = summary + "\n" + description
-			darcs_pull(hg_repo, darcs_repo, chash)
 			# The commit hash has a date like 20021020201112
 			# --------------------------------YYYYMMDDHHMMSS
 			date = chash.split("-")[0]
 			epoch = int(mktime(strptime(date, '%Y%m%d%H%M%S')))
+			darcs_pull(hg_repo, darcs_repo, chash)
+			for change, arg in darcs_changes_summary(darcs_repo, chash):
+				hg_handle_change(hg_repo, change, arg)
 			hg_commit(hg_repo, text, author, epoch)
 		change_number += 1
 	print "Darcs repository (_darcs) was not deleted. You can keep or remove it."
 
 # EOF