Merge branch 'py3' of https://github.com/eli-schwartz/calibre

bypy/macos/__main__.py

@@ -72,7 +72,8 @@ gcc = os.environ.get('CC', 'clang')
 def compile_launchers(contents_dir, xprograms, pyver):
     base = dirname(abspath(__file__))
     lib = compile_launcher_lib(contents_dir, gcc, base)
-    src = open(join(base, 'launcher.c'), 'rb').read().decode('utf-8')
+    with open(join(base, 'launcher.c'), 'rb') as f:
+        src = f.read().decode('utf-8')
     env, env_vals = [], []
     for key, val in ENV.items():
         env.append('"%s"' % key)
@@ -450,7 +451,8 @@ class Freeze(object):
         src = os.path.join(PREFIX, 'etc', 'fonts')
         shutil.copytree(src, dst, symlinks=False)
         fc = os.path.join(dst, 'fonts.conf')
-        raw = open(fc, 'rb').read().decode('utf-8')
+        with open(fc, 'rb') as f:
+            raw = f.read().decode('utf-8')
         raw = raw.replace('<dir>/usr/share/fonts</dir>', '''\
         <dir>/Library/Fonts</dir>
         <dir>/System/Library/Fonts</dir>

bypy/macos/sign.py

@@ -42,7 +42,8 @@ def make_certificate_useable():
         # Unlock keychain
         run('security unlock-keychain -p "{}" "{}"'.format(KEYCHAIN_PASSWORD, KEYCHAIN))
         # Add certificate to keychain
-        cert_pass = open(CODESIGN_CREDS).read().strip()
+        with open(CODESIGN_CREDS, 'r') as f:
+            cert_pass = f.read().strip()
         # Add certificate to keychain and allow codesign to use it
         # Use -A instead of -T /usr/bin/codesign to allow all apps to use it
         run('security import {} -k "{}" -P "{}" -T "/usr/bin/codesign"'.format(

bypy/windows/__main__.py

@@ -305,7 +305,8 @@ def embed_resources(env, module, desc=None, extra_data=None, product_description
     icon_map = {'calibre': 'library', 'ebook-viewer': 'viewer', 'ebook-edit': 'ebook-edit',
                 'lrfviewer': 'viewer', 'calibre-portable': 'library'}
     file_type = 'DLL' if module.endswith('.dll') else 'APP'
-    template = open(env.rc_template, 'rb').read().decode('utf-8')
+    with open(env.rc_template, 'rb') as f:
+        template = f.read().decode('utf-8')
     bname = b(module)
     internal_name = os.path.splitext(bname)[0]
     icon = icon_map.get(internal_name, 'command-prompt')

bypy/windows/wix.py

@@ -29,7 +29,8 @@ def create_installer(env):
         shutil.rmtree(env.installer_dir)
     os.makedirs(env.installer_dir)
 
-    template = open(j(d(__file__), 'wix-template.xml'), 'rb').read().decode('utf-8')
+    with open(j(d(__file__), 'wix-template.xml'), 'rb') as f:
+        template = f.read().decode('utf-8')
 
     components, smap = get_components_from_files(env)
     wxs = template.format(
@@ -50,7 +51,8 @@ def create_installer(env):
         editor_icon=j(env.src_root, 'icons', 'ebook-edit.ico'),
         web_icon=j(env.src_root, 'icons', 'web.ico'),
     )
-    template = open(j(d(__file__), 'en-us.xml'), 'rb').read().decode('utf-8')
+    with open(j(d(__file__), 'en-us.xml'), 'rb') as f:
+        template = f.read().decode('utf-8')
     enus = template.format(app=calibre_constants['appname'])
 
     enusf = j(env.installer_dir, 'en-us.wxl')

setup/__init__.py

@@ -95,7 +95,8 @@ def require_clean_git():
 def initialize_constants():
     global __version__, __appname__, modules, functions, basenames, scripts
 
-    src = open(os.path.join(SRC, 'calibre/constants.py'), 'rb').read().decode('utf-8')
+    with open(os.path.join(SRC, 'calibre/constants.py'), 'rb') as f:
+        src = f.read().decode('utf-8')
     nv = re.search(r'numeric_version\s+=\s+\((\d+), (\d+), (\d+)\)', src)
     __version__ = '%s.%s.%s'%(nv.group(1), nv.group(2), nv.group(3))
     __appname__ = re.search(r'__appname__\s+=\s+(u{0,1})[\'"]([^\'"]+)[\'"]',

setup/build.py

@@ -454,7 +454,8 @@ class Build(Command):
             self.info(' '.join(cmd))
             self.check_call(cmd)
             self.info('')
-        raw = open(sbf, 'rb').read().decode('utf-8')
+        with open(sbf, 'rb') as f:
+            raw = f.read().decode('utf-8')
 
         def read(x):
             ans = re.search(r'^%s\s*=\s*(.+)$' % x, raw, flags=re.M).group(1).strip()

setup/linux-installer.py

@@ -748,7 +748,8 @@ except NameError:
 
 def update_intaller_wrapper():
     # To run: python3 -c "import runpy; runpy.run_path('setup/linux-installer.py', run_name='update_wrapper')"
-    src = open(__file__, 'rb').read().decode('utf-8')
+    with open(__file__, 'rb') as f:
+        src = f.read().decode('utf-8')
     wrapper = os.path.join(os.path.dirname(os.path.abspath(__file__)), 'linux-installer.sh')
     with open(wrapper, 'r+b') as f:
         raw = f.read().decode('utf-8')

setup/port.py

@@ -211,7 +211,8 @@ class IteratorsCheck(Base):
 
     def get_errors_in_file(self, f):
         pat = re.compile(r'\b(range|map|filter|zip)\(')
-        text = open(f, 'rb').read().decode('utf-8')
+        with open(f, 'rb') as f:
+            text = f.read().decode('utf-8')
         matches = tuple(pat.finditer(text))
         if not matches:
             return []

setup/translations.py

@@ -665,7 +665,8 @@ class GetTranslations(Translations):  # {{{
             return errs
 
         def check_for_control_chars(f):
-            raw = open(f, 'rb').read().decode('utf-8')
+            with open(f, 'rb') as f:
+                raw = f.read().decode('utf-8')
             pat = re.compile(type(u'')(r'[\0-\x08\x0b\x0c\x0e-\x1f\x7f\x80-\x9f]'))
             errs = []
             for i, line in enumerate(raw.splitlines()):

src/calibre/db/tests/filesystem.py

@@ -74,12 +74,11 @@ class FilesystemTest(BaseTest):
         cl = self.cloned_library
         cache = self.init_cache(cl)
         fpath = cache.format_abspath(1, 'FMT1')
-        f = open(fpath, 'rb')
+        with open(fpath, 'rb') as f:
-        with self.assertRaises(IOError):
+            with self.assertRaises(IOError):
-            cache.set_field('title', {1:'Moved'})
+                cache.set_field('title', {1:'Moved'})
-        with self.assertRaises(IOError):
+            with self.assertRaises(IOError):
-            cache.remove_books({1})
+                cache.remove_books({1})
-        f.close()
         self.assertNotEqual(cache.field_for('title', 1), 'Moved', 'Title was changed despite file lock')
 
         # Test on folder with hardlinks

src/calibre/ebooks/conversion/plugins/djvu_input.py

@@ -38,22 +38,21 @@ class DJVUInput(InputFormatPlugin):
             setattr(options, opt.option.name, opt.recommended_value)
         options.input_encoding = 'utf-8'
         base = getcwd()
-        fname = os.path.join(base, 'index.html')
+        htmlfile = os.path.join(base, 'index.html')
         c = 0
-        while os.path.exists(fname):
+        while os.path.exists(htmlfile):
             c += 1
-            fname = os.path.join(base, 'index%d.html'%c)
+            htmlfile = os.path.join(base, 'index%d.html'%c)
-        htmlfile = open(fname, 'wb')
+        with open(htmlfile, 'wb') as f:
-        with htmlfile:
+            f.write(html.encode('utf-8'))
-            htmlfile.write(html.encode('utf-8'))
         odi = options.debug_pipeline
         options.debug_pipeline = None
         # Generate oeb from html conversion.
-        with open(htmlfile.name, 'rb') as f:
+        with open(htmlfile, 'rb') as f:
             oeb = html_input.convert(f, options, 'html', log,
                 {})
         options.debug_pipeline = odi
-        os.remove(htmlfile.name)
+        os.remove(htmlfile)
 
         # Set metadata from file.
         from calibre.customize.ui import get_file_type_metadata

src/calibre/ebooks/conversion/plugins/html_input.py

@@ -307,7 +307,8 @@ class HTMLInput(InputFormatPlugin):
         if link is None or not os.access(link, os.R_OK) or os.path.isdir(link):
             return (None, None)
         try:
-            raw = open(link, 'rb').read().decode('utf-8', 'replace')
+            with open(link, 'rb') as f:
+                raw = f.read().decode('utf-8', 'replace')
             raw = self.oeb.css_preprocessor(raw, add_namespace=False)
         except:
             self.log.exception('Failed to read CSS file: %r'%link)

src/calibre/ebooks/conversion/plugins/htmlz_input.py

@@ -88,21 +88,21 @@ class HTMLZInput(InputFormatPlugin):
             setattr(options, opt.option.name, opt.recommended_value)
         options.input_encoding = 'utf-8'
         base = getcwd()
-        fname = os.path.join(base, u'index.html')
+        htmlfile = os.path.join(base, u'index.html')
         c = 0
-        while os.path.exists(fname):
+        while os.path.exists(htmlfile):
             c += 1
-            fname = u'index%d.html'%c
+            htmlfile = u'index%d.html'%c
-        htmlfile = open(fname, 'wb')
+        with open(htmlfile, 'wb') as f:
-        with htmlfile:
+            f.write(html.encode('utf-8'))
-            htmlfile.write(html.encode('utf-8'))
         odi = options.debug_pipeline
         options.debug_pipeline = None
         # Generate oeb from html conversion.
-        oeb = html_input.convert(open(htmlfile.name, 'rb'), options, 'html', log,
+        with open(htmlfile, 'rb') as f:
+            oeb = html_input.convert(f, options, 'html', log,
                 {})
         options.debug_pipeline = odi
-        os.remove(htmlfile.name)
+        os.remove(htmlfile)
 
         # Set metadata from file.
         from calibre.customize.ui import get_file_type_metadata

src/calibre/ebooks/conversion/plumber.py

@@ -1191,7 +1191,8 @@ OptionRecommendation(name='search_replace',
             self.log('Structured HTML written to:', out_dir)
 
         if self.opts.extra_css and os.path.exists(self.opts.extra_css):
-            self.opts.extra_css = open(self.opts.extra_css, 'rb').read()
+            with open(self.opts.extra_css, 'rb') as f:
+                self.opts.extra_css = f.read()
 
         oibl = self.opts.insert_blank_line
         orps  = self.opts.remove_paragraph_spacing

src/calibre/ebooks/djvu/djvubzzdec.py

@@ -734,7 +734,8 @@ class BZZDecoder():
 def main():
     import sys
     from calibre.constants import plugins
-    raw = open(sys.argv[1], "rb").read()
+    with open(sys.argv[1], "rb") as f:
+        raw = f.read()
     d = plugins['bzzdec'][0]
     print(d.decompress(raw))
 

src/calibre/ebooks/lrf/html/convert_from.py

@@ -266,7 +266,8 @@ class HTMLConverter(object):
 
         if self._override_css is not None:
             if os.access(self._override_css, os.R_OK):
-                src = open(self._override_css, 'rb').read()
+                with open(self._override_css, 'rb') as f:
+                    src = f.read()
             else:
                 src = self._override_css
             if isinstance(src, bytes):

src/calibre/ebooks/lrf/meta.py

@@ -712,7 +712,8 @@ def main(args=sys.argv):
         lrf.book_id = options.book_id
     if options.comment:
         path = os.path.expanduser(os.path.expandvars(options.comment))
-        lrf.free_text = open(path, 'rb').read().decode('utf-8', 'replace')
+        with open(path, 'rb') as f:
+            lrf.free_text = f.read().decode('utf-8', 'replace')
     if options.get_thumbnail:
         t = lrf.thumbnail
         td = "None"

src/calibre/ebooks/metadata/topaz.py

@@ -391,14 +391,13 @@ if __name__ == '__main__':
         print(get_metadata(open(sys.argv[1], 'rb')))
     else:
         # Test set_metadata()
-        data = open(sys.argv[1], 'rb')
         stream = io.BytesIO()
-        stream.write(data.read())
+        with open(sys.argv[1], 'rb') as data:
+            stream.write(data.read())
         mi = MetaInformation(title="Updated Title", authors=['Author, Random'])
         set_metadata(stream, mi)
 
         # Write the result
         tokens = sys.argv[1].rpartition('.')
-        updated_data = open(tokens[0]+'-updated' + '.' + tokens[2],'wb')
+        with open(tokens[0]+'-updated' + '.' + tokens[2],'wb') as updated_data:
-        updated_data.write(stream.getvalue())
+            updated_data.write(stream.getvalue())
-        updated_data.close()

src/calibre/ebooks/oeb/iterator/bookmarks.py

@@ -87,12 +87,12 @@ class BookmarksMixin(object):
         if not no_copy_to_file and self.copy_bookmarks_to_file and os.path.splitext(
                 self.pathtoebook)[1].lower() == '.epub' and os.access(self.pathtoebook, os.W_OK):
             try:
-                zf = open(self.pathtoebook, 'r+b')
+                with open(self.pathtoebook, 'r+b') as zf:
+                    safe_replace(zf, 'META-INF/calibre_bookmarks.txt',
+                            BytesIO(dat.encode('utf-8')),
+                            add_missing=True)
             except IOError:
                 return
-            safe_replace(zf, 'META-INF/calibre_bookmarks.txt',
-                    BytesIO(dat.encode('utf-8')),
-                    add_missing=True)
 
     def add_bookmark(self, bm, no_copy_to_file=False):
         self.bookmarks = [x for x in self.bookmarks if x['title'] !=

src/calibre/ebooks/oeb/transforms/metadata.py

@@ -124,9 +124,10 @@ class MergeMetadata(object):
             self.oeb.metadata.add('identifier', mi.application_id, scheme='calibre')
 
     def set_cover(self, mi, prefer_metadata_cover):
-        cdata, ext = '', 'jpg'
+        cdata, ext = b'', 'jpg'
         if mi.cover and os.access(mi.cover, os.R_OK):
-            cdata = open(mi.cover, 'rb').read()
+            with open(mi.cover, 'rb') as f:
+                cdata = f.read()
             ext = mi.cover.rpartition('.')[-1].lower().strip()
         elif mi.cover_data and mi.cover_data[-1]:
             cdata = mi.cover_data[1]
@@ -137,7 +138,7 @@ class MergeMetadata(object):
         if 'cover' in self.oeb.guide:
             old_cover = self.oeb.guide['cover']
         if prefer_metadata_cover and old_cover is not None:
-            cdata = ''
+            cdata = b''
         if cdata:
             self.oeb.guide.remove('cover')
             self.oeb.guide.remove('titlepage')

src/calibre/ebooks/rtf/preprocess.py

@@ -368,15 +368,13 @@ if __name__ == "__main__":
     if len(sys.argv) < 2:
         print("Usage %prog rtfFileToConvert")
         sys.exit()
-    f = open(sys.argv[1], 'rb')
+    with open(sys.argv[1], 'rb') as f:
-    data = f.read()
+        data = f.read()
-    f.close()
 
     tokenizer = RtfTokenizer(data)
     parsedTokens = RtfTokenParser(tokenizer.tokens)
 
     data = parsedTokens.toRTF()
 
-    f = open(sys.argv[1], 'w')
+    with open(sys.argv[1], 'w') as f:
-    f.write(data)
+        f.write(data)
-    f.close()

src/calibre/ebooks/snb/snbfile.py

@@ -39,10 +39,9 @@ class SNBFile:
     def Open(self, inputFile):
         self.fileName = inputFile
 
-        snbFile = open(self.fileName, "rb")
+        with open(self.fileName, "rb") as f:
-        snbFile.seek(0)
+            f.seek(0)
-        self.Parse(snbFile)
+            self.Parse(f)
-        snbFile.close()
 
     def Parse(self, snbFile, metaOnly=False):
         # Read header
@@ -158,7 +157,8 @@ class SNBFile:
         f = FileStream()
         f.attr = 0x41000000
         f.fileSize = os.path.getsize(os.path.join(tdir,fileName))
-        f.fileBody = open(os.path.join(tdir,fileName), 'rb').read()
+        with open(os.path.join(tdir,fileName), 'rb') as data:
+            f.fileBody = data.read()
         f.fileName = fileName.replace(os.sep, '/')
         if isinstance(f.fileName, unicode_type):
             f.fileName = f.fileName.encode("ascii", "ignore")
@@ -168,7 +168,8 @@ class SNBFile:
         f = FileStream()
         f.attr = 0x01000000
         f.fileSize = os.path.getsize(os.path.join(tdir,fileName))
-        f.fileBody = open(os.path.join(tdir,fileName), 'rb').read()
+        with open(os.path.join(tdir,fileName), 'rb') as data:
+            f.fileBody = data.read()
         f.fileName = fileName.replace(os.sep, '/')
         if isinstance(f.fileName, unicode_type):
             f.fileName = f.fileName.encode("ascii", "ignore")
@@ -186,9 +187,8 @@ class SNBFile:
             fname = os.path.basename(f.fileName)
             root, ext = os.path.splitext(fname)
             if ext in ['.jpeg', '.jpg', '.gif', '.svg', '.png']:
-                file = open(os.path.join(path, fname), 'wb')
+                with open(os.path.join(path, fname), 'wb') as outfile:
-                file.write(f.fileBody)
+                    outfile.write(f.fileBody)
-                file.close()
                 fileNames.append((fname, guess_type('a'+ext)[0]))
         return fileNames
 
@@ -297,9 +297,8 @@ class SNBFile:
             print("File Size: ", f.fileSize)
             print("Block Index: ", f.blockIndex)
             print("Content Offset: ", f.contentOffset)
-            tempFile = open("/tmp/" + f.fileName, 'wb')
+            with open("/tmp/" + f.fileName, 'wb') as tempFile:
-            tempFile.write(f.fileBody)
+                tempFile.write(f.fileBody)
-            tempFile.close()
 
 
 def usage():

src/calibre/gui2/actions/edit_metadata.py

@@ -937,7 +937,8 @@ class EditMetadataAction(InterfaceAction):
                 if old != prefs['read_file_metadata']:
                     prefs['read_file_metadata'] = old
             if mi.cover and os.access(mi.cover, os.R_OK):
-                cdata = open(mi.cover).read()
+                with open(mi.cover, 'rb') as f:
+                    cdata = f.read()
             elif mi.cover_data[1] is not None:
                 cdata = mi.cover_data[1]
             if cdata is None:

src/calibre/gui2/convert/metadata.py

@@ -198,10 +198,10 @@ class MetadataWidget(Widget, Ui_Form):
                         _('You do not have permission to read the file: ') + _file)
                 d.exec_()
                 return
-            cf, cover = None, None
+            cover = None
             try:
-                cf = open(_file, "rb")
+                with open(_file, "rb") as f:
-                cover = cf.read()
+                    cover = f.read()
             except IOError as e:
                 d = error_dialog(self.parent(), _('Error reading file'),
                         _("<p>There was an error reading from file: <br /><b>") + _file + "</b></p><br />"+str(e))

src/calibre/gui2/dialogs/custom_recipes.py

@@ -606,7 +606,8 @@ class CustomRecipes(Dialog):
         if files:
             path = files[0]
             try:
-                src = open(path, 'rb').read().decode('utf-8')
+                with open(path, 'rb') as f:
+                    src = f.read().decode('utf-8')
             except Exception as err:
                 error_dialog(self, _('Invalid input'),
                         _('<p>Could not create recipe. Error:<br>%s')%err, show=True)

src/calibre/gui2/main.py

@@ -577,7 +577,8 @@ if __name__ == '__main__':
         from PyQt5.Qt import QErrorMessage
         logfile = os.path.join(os.path.expanduser('~'), 'calibre.log')
         if os.path.exists(logfile):
-            log = open(logfile).read().decode('utf-8', 'ignore')
+            with open(logfile) as f:
+                log = f.read().decode('utf-8', 'ignore')
             d = QErrorMessage()
             d.showMessage(('<b>Error:</b>%s<br><b>Traceback:</b><br>'
                 '%s<b>Log:</b><br>%s')%(unicode_type(err),

src/calibre/gui2/metadata/basic_widgets.py

@@ -1168,10 +1168,10 @@ class Cover(ImageView):  # {{{
                         _('You do not have permission to read the file: ') + _file)
                 d.exec_()
                 return
-            cf, cover = None, None
+            cover = None
             try:
-                cf = open(_file, "rb")
+                with open(_file, "rb") as f:
-                cover = cf.read()
+                    cover = f.read()
             except IOError as e:
                 d = error_dialog(
                         self, _('Error reading file'),

src/calibre/gui2/metadata/single.py

@@ -461,7 +461,8 @@ class MetadataSingleDialogBase(QDialog):
             return
         cdata = None
         if mi.cover and os.access(mi.cover, os.R_OK):
-            cdata = open(mi.cover).read()
+            with open(mi.cover, 'rb') as f:
+                cdata = f.read()
         elif mi.cover_data[1] is not None:
             cdata = mi.cover_data[1]
         if cdata is None:

src/calibre/gui2/tweak_book/diff/main.py

@@ -139,7 +139,8 @@ def string_diff(left, right, left_syntax=None, right_syntax=None, left_name='lef
 def file_diff(left, right):
     (raw1, syntax1), (raw2, syntax2) = map(get_decoded_raw, (left, right))
     if type(raw1) is not type(raw2):
-        raw1, raw2 = open(left, 'rb').read(), open(right, 'rb').read()
+        with open(left, 'rb') as f1, open(right, 'rb') as f2:
+            raw1, raw2 = f1.read(), f2.read()
     cache = Cache()
     cache.set_left(left, raw1), cache.set_right(right, raw2)
     changed_names = {} if raw1 == raw2 else {left:right}

src/calibre/gui2/tweak_book/editor/syntax/html.py

@@ -606,7 +606,8 @@ def profile():
     from calibre.gui2.tweak_book.editor.themes import get_theme
     app = Application([])
     set_book_locale('en')
-    raw = open(sys.argv[-2], 'rb').read().decode('utf-8')
+    with open(sys.argv[-2], 'rb') as f:
+        raw = f.read().decode('utf-8')
     doc = QTextDocument()
     doc.setPlainText(raw)
     h = Highlighter()

src/calibre/utils/fonts/utils.py

@@ -487,9 +487,10 @@ def test():
 
 def main():
     import sys, os
-    for f in sys.argv[1:]:
+    for arg in sys.argv[1:]:
-        print(os.path.basename(f))
+        print(os.path.basename(arg))
-        raw = open(f, 'rb').read()
+        with open(arg, 'rb') as f:
+            raw = f.read()
         print(get_font_names(raw))
         characs = get_font_characteristics(raw)
         print(characs)

src/calibre/utils/fonts/win_fonts.py

@@ -147,9 +147,10 @@ def load_winfonts():
 
 
 def test_ttf_reading():
-    for f in sys.argv[1:]:
+    for arg in sys.argv[1:]:
-        raw = open(f).read()
+        with open(arg, 'rb') as f:
-        print(os.path.basename(f))
+            raw = f.read()
+        print(os.path.basename(arg))
         get_font_characteristics(raw)
         print()
 

src/calibre/utils/ip_routing.py

@@ -70,7 +70,8 @@ else:
 
     def get_default_route_src_address():
         # Use /proc/net/ipv6_route for IPv6 addresses
-        raw = open('/proc/net/route', 'rb').read().decode('utf-8')
+        with open('/proc/net/route', 'rb') as f:
+            raw = f.read().decode('utf-8')
         for line in raw.splitlines():
             parts = line.split()
             if len(parts) > 1 and parts[1] == '00000000':

src/calibre/web/feeds/news.py

@@ -1299,7 +1299,8 @@ class BasicNewsRecipe(Recipe):
                 cdata = cu.read()
                 cu = getattr(cu, 'name', 'cover.jpg')
             elif os.access(cu, os.R_OK):
-                cdata = open(cu, 'rb').read()
+                with open(cu, 'rb') as f:
+                    cdata = f.read()
             else:
                 self.report_progress(1, _('Downloading cover from %s')%cu)
                 with closing(self.browser.open(cu)) as r:

src/calibre/web/feeds/recipes/collection.py

@@ -114,7 +114,8 @@ def get_custom_recipe_collection(*args):
         title, fname = x
         recipe = os.path.join(bdir, fname)
         try:
-            recipe = open(recipe, 'rb').read().decode('utf-8')
+            with open(recipe, 'rb') as f:
+                recipe = f.read().decode('utf-8')
             recipe_class = compile_recipe(recipe)
             if recipe_class is not None:
                 rmap['custom:%s'%id_] = recipe_class

update-on-ox

@@ -35,7 +35,8 @@ HOST = 'ox'
 
 base = os.path.dirname(os.path.abspath(__file__))
 if True:
-    raw = open(os.path.join(base, 'src/calibre/constants.py')).read()
+    with open(os.path.join(base, 'src/calibre/constants.py')) as f:
+        raw = f.read()
     v = re.search(r'numeric_version\s*=\s*(\(.+?\))', raw).group(1)
     v = '.'.join(map(str, ast.literal_eval(v)))
     dmg = f'calibre-{v}.dmg'
@@ -47,7 +48,8 @@ def run(what):
         raise SystemExit(ret.returncode)
 
 
-script = open(__file__, 'rb').read().decode('utf-8')
+with open(__file__, 'rb') as f:
+    script = f.read().decode('utf-8')
 script = script[:script.find('# EOF_REMOTE')].replace('if False:', 'if True:', 1)
 os.chdir(os.path.expanduser('~/work/build-calibre'))
 with tempfile.NamedTemporaryFile(prefix='install-dmg-', suffix='.py') as f: