Python3: NameError: name 'unichr' is not defined / SyntaxError: invalid syntax

[Peter Suter]

Plugin fails in Python 3:

	Traceback (most recent call last):
	  File "trac\loader.py", line 80, in _load_eggs
		entry.load(require=True)
	  File "pkg_resources\__init__.py", line 2443, in load
		return self.resolve()
	  File "pkg_resources\__init__.py", line 2449, in resolve
		module = __import__(self.module_name, fromlist=['__name__'], level=0)
	  File "mailarchive\web_ui.py", line 24, in <module>
		from mailarchive.model import ArchivedMail
	  File "mailarchive\model.py", line 44, in <module>
		map(unichr, xrange(0x10000)))) +
	NameError: name 'unichr' is not defined

	Traceback (most recent call last):
	  File "trac\loader.py", line 80, in _load_eggs
		entry.load(require=True)
	  File "pkg_resources\__init__.py", line 2443, in load
		return self.resolve()
	  File "pkg_resources\__init__.py", line 2449, in resolve
		module = __import__(self.module_name, fromlist=['__name__'], level=0)
	  File "mailarchive\admin.py", line 52
		print "Skipping mail with UID %s" % (uid,)
			  ^
	SyntaxError: invalid syntax (admin.py, line 52)

[Peter Suter]

mailarchive/admin.py

@@ -1 +1 @@
 # -*- coding: utf-8 -*-
 
+from __future__ import print_function
+
 import imaplib
 import datetime
 import os
@@ -49 +51 @@
 
             # No duplicates
             if ArchivedMail.select_by_id(self.env, uid) is not None:
-                print "Skipping mail with UID %s" % (uid,)
+                print("Skipping mail with UID %s" % (uid,))
                 continue
 
             typ, data = imap_conn.uid('fetch', uid, '(RFC822)')

mailarchive/model.py

@@ -15 +15 @@
 from trac.util.datefmt import from_utimestamp, to_utimestamp, utc
 from trac.util.text import stripws
 
+try:
+    unichr
+except NameError:
+    unichr = chr # In Python 3 chr can be used instead of unichr in Python 2
+
+try:
+    xrange
+except NameError:
+    xrange = range # In Python 3 range can be used instead of xrange in Python 2
 
 SCHEMA = [
     Table('mailarchive', key='id')[

mailarchive/web_ui.py

@@ -201 +201 @@
                 for part in header[len(h):].split(' ')
                 if part
                 for found_mail in ArchivedMail.search(self.env, [part.strip()])
-            }.iteritems())
+            }.items())
         ]
 
         resource = Resource('mailarchive', id)

[lucid]

In 17666:

MailArchivePlugin: Python3 compatibility.
(see #13739)