if dist_fallback and `dpkg -S` fails to find the right package name,

fall back to package name recommended by Debian Python Policy (use
debian/pydist-override file to override)

debian/changelog

@@ -5,6 +5,9 @@ python-defaults (2.6.6-2) UNRELEASED; urgency=low
     - add dist_fallback file with a list of Python distribution name and
       Debian package name pairs (to be used as a fall back source for
       PyDist feature)
+    - if dist_fallback and `dpkg -S` fails to find the right package name,
+      fall back to package name recommended by Debian Python Policy (use
+      debian/pydist-override file to override)
     - TODO: disable PyDist feature if dh_pydeb is in debian/rules
   * use /usr/bin/python rather than python in python-minimal.postinst
     (closes: 595826)

debpython/pydist.py

@@ -33,11 +33,11 @@ log = logging.getLogger('dh_python')
 PUBLIC_DIR_RE = re.compile(r'.*?/usr/lib/python(\d.\d+)/(site|dist)-packages')
 PYDIST_RE = re.compile(r"""
     (?P<name>[A-Za-z][A-Za-z0-9_.]*)             # Python distribution name
-    \s+
+    \s*
     (?P<vrange>(?:-?\d\.\d+(?:-(?:\d\.\d+)?)?)?) # version range
     \s*
-    (?P<dependency>[a-z][^;]*)                   # Debian dependency
-    (?: # optional upstream version -> Debian version translator
+    (?P<dependency>(?:[a-z][^;]*)?)              # Debian dependency
+    (?:  # optional upstream version -> Debian version translator
         ;\s*
         (?P<standard>PEP386)?                    # PEP-386 mode
         \s*
@@ -45,9 +45,11 @@ PYDIST_RE = re.compile(r"""
     )?
     """, re.VERBOSE)
 REQUIRES_RE = re.compile(r'''
-    (?P<name>[A-Za-z][A-Za-z0-9_.]*)
+    (?P<name>[A-Za-z][A-Za-z0-9_.]*)     # Python distribution name
+    \s*
+    (?P<enabled_extras>(?:\[[^\]]*\])?)  # ignored for now
     \s*
-    (?: # optional version
+    (?:  # optional minimum/maximum version
         (?P<operator><=?|>=?|==|!=)
         \s*
         (?P<version>(\w|[-.])+)
@@ -91,7 +93,11 @@ def load(dname='/usr/share/python/dist/', fname='debian/pydist-overrides',
                 line = line.strip('\r\n')
                 if line.startswith('#') or not line:
                     continue
-                dist = PYDIST_RE.search(line).groupdict()
+                dist = PYDIST_RE.search(line)
+                if not dist:
+                    log.error('%s file has a broken line: %s', fpath, line)
+                    exit(9)
+                dist = dist.groupdict()
                 name = safe_name(dist['name'])
                 dist['versions'] = get_requested_versions(dist['vrange'])
                 dist['dependency'] = dist['dependency'].strip()
@@ -116,10 +122,10 @@ def guess_dependency(req, version=None):
     data = load()
     req_dict = REQUIRES_RE.match(req)
     if not req_dict:
-        log.warning('requirement is not valid: %s', req)
+        log.error('requirement is not valid: %s', req)
         log.info('please ask dh_python2 author to fix REQUIRES_RE '
                  'or your upstream author to fix requires.txt')
-        return set()  # should we sys.exit(1) here?
+        exit(8)
     req_dict = req_dict.groupdict()
     details = data.get(req_dict['name'].lower())
     if details:
@@ -128,6 +134,8 @@ def guess_dependency(req, version=None):
                 # rule doesn't match version, try next one
                 continue
 
+            if not item['dependency']:
+                return  # this requirement should be ignored
             if item['dependency'].endswith(')'):
                 # no need to translate versions if version is hardcoded in Debian
                 # dependency
@@ -139,8 +147,7 @@ def guess_dependency(req, version=None):
                 return item['dependency']
 
     # try dpkg -S
-
-    query = "'%s-?*\.egg-info'" % name  # TODO: .dist-info
+    query = "'%s-?*\.egg-info'" % safe_name(name)  # TODO: .dist-info
     if version:
         query = "%s | grep '/python%s/\|/pyshared/'" % \
                 (query, vrepr(version))
@@ -151,22 +158,24 @@ def guess_dependency(req, version=None):
     process = Popen("/usr/bin/dpkg -S %s" % query, \
                     shell=True, stdout=PIPE)
     stdout, stderr = process.communicate()
-    if process.returncode != 0:
-        log.error('Cannot find package that provides %s. '
-                  'Please add it to debian/pydist-overrides', name)
-        log.info("hint: `apt-file search -x '(packages|pyshared)/" +\
-                  "%s' -l` might help", name)
-        exit(8)
+    if process.returncode == 0:
+        result = set()
+        for line in stdout.split('\n'):
+            if not line.strip():
+                continue
+            result.add(line.split(':')[0])
+        if len(result) > 1:
+            log.error('more than one package name found for %s dist', name)
+        else:
+            return result.pop()
 
-    result = set()
-    for line in stdout.split('\n'):
-        if not line.strip():
-            continue
-        result.add(line.split(':')[0])
-    if len(result) > 1:
-        log.error('more than one package name found for %s dist', name)
-        exit(9)
-    return result.pop()
+    # fall back to python-distname
+    pname = sensible_pname(name)
+    log.warn('Cannot find package that provides %s. '
+             'Using %s as package name. Please add "%s correct_package_name" '
+             'line to debian/pydist-overrides to override it.',
+             name, pname, name)
+    return pname
 
 
 def parse_pydep(fname):
@@ -193,3 +202,11 @@ def parse_pydep(fname):
 def safe_name(name):
     """Emulate distribute's safe_name."""
     return re.compile('[^A-Za-z0-9.]+').sub('_', name).lower()
+
+
+def sensible_pname(egg_name):
+    """Guess Debian package name from Egg name."""
+    egg_name = safe_name(egg_name).replace('_', '-')
+    if egg_name.startswith('python-'):
+        egg_name = egg_name[7:]
+    return "python-%s" % egg_name.lower()

pydist/Makefile

@@ -6,7 +6,7 @@ clean:
 	rm -f README.PyDist.html
 
 dist_fallback:
-	python ./generate_fallback_list.py
+	python ./generate_fallback_list.py --skip-sensible-names
 
 README.PyDist.html:
 	rst2html README.PyDist README.PyDist.html

pydist/README.PyDist

@@ -25,6 +25,7 @@ Examples:
 DEPENDENCY
 ``````````
 Debian dependency, multiple packages or versions are allowed.
+If not set, given Python distribution name will be ignored.
 
 Examples:
  * python-mako
@@ -77,5 +78,6 @@ Complete examples:
  * Mako python-mako; PEP386
  * foo -2.5 python-oldfoo; s/^/3:/
  * foo 2.5- python-foo; PEP386
+ * Bar 2.6-
 
 .. vim: ft=rst

pydist/generate_fallback_list.py

@@ -24,6 +24,15 @@ import os
 import sys
 from subprocess import Popen, PIPE
 
+skip_sensible_names = True if '--skip-sensible-names' in sys.argv else False
+os.chdir(os.path.dirname(__file__))
+if os.path.isdir('../debpython'):
+    sys.path.append('..')
+else:
+    sys.path.append('/usr/share/python/debpython/')
+from debpython.pydist import sensible_pname
+
+
 if not os.path.isdir('cache'):
     process = Popen('apt-file -s sources.list -c cache update', shell=True)
     process.communicate()
@@ -50,6 +59,8 @@ for line in stdout.splitlines():
                 if i.endswith('.egg-info')][0]
     if egg_name.endswith('.egg'):
         egg_name = egg_name[:-4]
+    if skip_sensible_names and sensible_pname(egg_name) == pname:
+        continue
     if egg_name not in processed:
         processed.add(egg_name)
         result.append("%s %s\n" % (egg_name, pname))

tests/t1/debian/pydist-overrides

@@ -2,3 +2,4 @@ Mako python-mako (>= 0.2)
 SQLAlchemy python-sqlalchemy (>= 0.6)
 Foo python-foo
 Bar python-bar
+Baz

tests/t1/setup.py

@@ -18,5 +18,5 @@ setup(name='Foo',
       packages=find_packages('lib/'),
       package_data = {'foo': ['jquery.js']},
       zip_safe=False,
-      install_requires = ['Mako', 'SQLAlchemy >=0.5'],
+      install_requires = ['Mako', 'SQLAlchemy >=0.5', 'Baz [extras]'],
 )