From cc172a2a48ae797a849ed892d6484c0685a5bb94 Mon Sep 17 00:00:00 2001
From: un-pogaz <46523284+un-pogaz@users.noreply.github.com>
Date: Fri, 24 Jan 2025 11:14:18 +0100
Subject: [PATCH] unnecessary map (auto-fix)
ruff 'C417' --unsafe-fixes
---
ruff-strict-pep8.toml | 2 +-
setup/__init__.py | 4 ++--
src/calibre/db/categories.py | 2 +-
src/calibre/db/cli/cmd_list.py | 4 ++--
src/calibre/db/cli/cmd_list_categories.py | 6 +++---
src/calibre/db/tests/base.py | 2 +-
src/calibre/devices/kindle/apnx_page_generator/pages.py | 4 ++--
src/calibre/ebooks/conversion/plugins/epub_output.py | 2 +-
src/calibre/ebooks/metadata/opf2.py | 9 ++++-----
src/calibre/ebooks/metadata/xmp.py | 2 +-
src/calibre/ebooks/mobi/utils.py | 2 +-
src/calibre/ebooks/pdb/haodoo/reader.py | 8 ++------
src/calibre/ebooks/pdf/render/gradients.py | 2 +-
src/calibre/gui2/dialogs/metadata_bulk.py | 6 ++----
src/calibre/gui2/dialogs/search.py | 3 +--
src/calibre/gui2/dialogs/template_dialog_code_widget.py | 2 +-
src/calibre/gui2/preferences/columns.py | 4 +---
src/calibre/gui2/preferences/create_custom_column.py | 3 +--
src/calibre/gui2/preferences/look_feel.py | 2 +-
src/calibre/gui2/preferences/texture_chooser.py | 2 +-
src/calibre/gui2/search_box.py | 4 +---
.../gui2/store/config/chooser/adv_search_builder.py | 3 +--
src/calibre/gui2/store/search/adv_search_builder.py | 3 +--
.../gui2/store/stores/mobileread/adv_search_builder.py | 3 +--
src/calibre/gui2/tweak_book/diff/view.py | 2 +-
src/calibre/gui2/tweak_book/editor/text.py | 2 +-
src/calibre/library/database2.py | 2 +-
src/calibre/srv/http_response.py | 2 +-
src/calibre/srv/tests/auth.py | 2 +-
src/calibre/srv/tests/loop.py | 2 +-
src/calibre/srv/users.py | 4 ++--
src/calibre/test_build.py | 2 +-
src/calibre/utils/matcher.py | 2 +-
33 files changed, 44 insertions(+), 60 deletions(-)
diff --git a/ruff-strict-pep8.toml b/ruff-strict-pep8.toml
index 54eec4a104..fb6af8e1e9 100644
--- a/ruff-strict-pep8.toml
+++ b/ruff-strict-pep8.toml
@@ -19,7 +19,7 @@ quote-style = 'single'
[lint]
ignore = [
'E402', 'E722', 'E741',
- 'UP012', 'UP030', 'UP032', 'UP038', 'C408', 'C413', 'C417', 'C420',
+ 'UP012', 'UP030', 'UP032', 'UP038', 'C408', 'C413', 'C420',
]
select = [
'E', 'F', 'I', 'W', 'INT',
diff --git a/setup/__init__.py b/setup/__init__.py
index d43f1e8dd4..2ced671aa4 100644
--- a/setup/__init__.py
+++ b/setup/__init__.py
@@ -46,10 +46,10 @@ def newer(targets, sources):
for f in targets:
if not os.path.exists(f):
return True
- ttimes = map(lambda x: os.stat(x).st_mtime, targets)
+ ttimes = (os.stat(x).st_mtime for x in targets)
oldest_target = min(ttimes)
try:
- stimes = map(lambda x: os.stat(x).st_mtime, sources)
+ stimes = (os.stat(x).st_mtime for x in sources)
newest_source = max(stimes)
except FileNotFoundError:
newest_source = oldest_target +1
diff --git a/src/calibre/db/categories.py b/src/calibre/db/categories.py
index fe25e70641..19ebb2994f 100644
--- a/src/calibre/db/categories.py
+++ b/src/calibre/db/categories.py
@@ -279,7 +279,7 @@ def get_categories(dbcache, sort='name', book_ids=None, first_letter_sort=False,
# temporarily duplicating the categories lists.
taglist = {}
for c, items in iteritems(categories):
- taglist[c] = dict(map(lambda t:(icu_lower(t.name), t), items))
+ taglist[c] = {icu_lower(t.name): t for t in items}
# Add the category values to the user categories
for user_cat in sorted(user_categories, key=sort_key):
diff --git a/src/calibre/db/cli/cmd_list.py b/src/calibre/db/cli/cmd_list.py
index cbb62578f4..a030c20bb6 100644
--- a/src/calibre/db/cli/cmd_list.py
+++ b/src/calibre/db/cli/cmd_list.py
@@ -205,7 +205,7 @@ def do_list(
from calibre.utils.terminal import ColoredStream, geometry
output_table = prepare_output_table(fields, book_ids, data, metadata)
- widths = list(map(lambda x: 0, fields))
+ widths = [0 for x in fields]
for record in output_table:
for j in range(len(fields)):
@@ -215,7 +215,7 @@ def do_list(
if not screen_width:
screen_width = 80
field_width = screen_width // len(fields)
- base_widths = list(map(lambda x: min(x + 1, field_width), widths))
+ base_widths = [min(x + 1, field_width) for x in widths]
while sum(base_widths) < screen_width:
adjusted = False
diff --git a/src/calibre/db/cli/cmd_list_categories.py b/src/calibre/db/cli/cmd_list_categories.py
index a0f3df64ad..b474beaed2 100644
--- a/src/calibre/db/cli/cmd_list_categories.py
+++ b/src/calibre/db/cli/cmd_list_categories.py
@@ -74,7 +74,7 @@ def do_list(fields, data, opts):
from calibre.utils.terminal import ColoredStream, geometry
separator = ' '
- widths = list(map(lambda x: 0, fields))
+ widths = [0 for x in fields]
for i in data:
for j, field in enumerate(fields):
widths[j] = max(widths[j], max(len(field), len(str(i[field]))))
@@ -83,7 +83,7 @@ def do_list(fields, data, opts):
if not screen_width:
screen_width = 80
field_width = screen_width // len(fields)
- base_widths = list(map(lambda x: min(x + 1, field_width), widths))
+ base_widths = [min(x + 1, field_width) for x in widths]
while sum(base_widths) < screen_width:
adjusted = False
@@ -104,7 +104,7 @@ def do_list(fields, data, opts):
with ColoredStream(sys.stdout, fg='green'):
prints(''.join(titles))
- wrappers = list(map(lambda x: TextWrapper(x - 1), widths))
+ wrappers = [TextWrapper(x - 1) for x in widths]
for record in data:
text = [
diff --git a/src/calibre/db/tests/base.py b/src/calibre/db/tests/base.py
index 26df5522e6..6af4ec2510 100644
--- a/src/calibre/db/tests/base.py
+++ b/src/calibre/db/tests/base.py
@@ -110,7 +110,7 @@ class BaseTest(unittest.TestCase):
continue
attr1, attr2 = getattr(mi1, attr), getattr(mi2, attr)
if attr == 'formats':
- attr1, attr2 = map(lambda x:tuple(x) if x else (), (attr1, attr2))
+ attr1, attr2 = (tuple(x) if x else () for x in (attr1, attr2))
if isinstance(attr1, (tuple, list)) and 'authors' not in attr and 'languages' not in attr:
attr1, attr2 = set(attr1), set(attr2)
self.assertEqual(attr1, attr2,
diff --git a/src/calibre/devices/kindle/apnx_page_generator/pages.py b/src/calibre/devices/kindle/apnx_page_generator/pages.py
index 6960c856f4..9c92bf4637 100644
--- a/src/calibre/devices/kindle/apnx_page_generator/pages.py
+++ b/src/calibre/devices/kindle/apnx_page_generator/pages.py
@@ -34,10 +34,10 @@ class Pages:
@property
def page_locations(self) -> list[int]:
- return list(itertools.chain.from_iterable(list(map(lambda pg: pg.page_locations, self.__pages_groups))))
+ return list(itertools.chain.from_iterable([pg.page_locations for pg in self.__pages_groups]))
@property
def number_of_pages(self) -> int:
- return sum(list(map(lambda pg: len(pg.page_locations), self.__pages_groups)))
+ return sum([len(pg.page_locations) for pg in self.__pages_groups])
diff --git a/src/calibre/ebooks/conversion/plugins/epub_output.py b/src/calibre/ebooks/conversion/plugins/epub_output.py
index 4662569008..6a41d42858 100644
--- a/src/calibre/ebooks/conversion/plugins/epub_output.py
+++ b/src/calibre/ebooks/conversion/plugins/epub_output.py
@@ -452,7 +452,7 @@ class EPUBOutput(OutputFormatPlugin):
br.tag = XHTML('p')
br.text = '\u00a0'
style = br.get('style', '').split(';')
- style = list(filter(None, map(lambda x: x.strip(), style)))
+ style = list(filter(None, (x.strip() for x in style)))
style.append('margin:0pt; border:0pt')
# If the prior tag is a block (including a
we replaced)
# then this
replacement should have a 1-line height.
diff --git a/src/calibre/ebooks/metadata/opf2.py b/src/calibre/ebooks/metadata/opf2.py
index 6232cce9d4..4516fbcae8 100644
--- a/src/calibre/ebooks/metadata/opf2.py
+++ b/src/calibre/ebooks/metadata/opf2.py
@@ -1432,9 +1432,8 @@ class OPFCreator(Metadata):
`entries`: List of (path, mime-type) If mime-type is None it is autodetected
'''
- entries = list(map(lambda x: x if os.path.isabs(x[0]) else
- (os.path.abspath(os.path.join(self.base_path, x[0])), x[1]),
- entries))
+ entries = [x if os.path.isabs(x[0]) else
+ (os.path.abspath(os.path.join(self.base_path, x[0])), x[1]) for x in entries]
self.manifest = Manifest.from_paths(entries)
self.manifest.set_basedir(self.base_path)
@@ -1464,8 +1463,8 @@ class OPFCreator(Metadata):
`entries`: List of paths
'''
- entries = list(map(lambda x: x if os.path.isabs(x) else
- os.path.abspath(os.path.join(self.base_path, x)), entries))
+ entries = [x if os.path.isabs(x) else
+ os.path.abspath(os.path.join(self.base_path, x)) for x in entries]
self.spine = Spine.from_paths(entries, self.manifest)
def set_toc(self, toc):
diff --git a/src/calibre/ebooks/metadata/xmp.py b/src/calibre/ebooks/metadata/xmp.py
index 1dfabe3194..b2eb7021c9 100644
--- a/src/calibre/ebooks/metadata/xmp.py
+++ b/src/calibre/ebooks/metadata/xmp.py
@@ -495,7 +495,7 @@ def metadata_to_xmp_packet(mi):
if not mi.is_null('pubdate'):
create_sequence_property(dc, 'dc:date', [isoformat(mi.pubdate, as_utc=False)]) # Adobe spec recommends local time
if not mi.is_null('languages'):
- langs = list(filter(None, map(lambda x:lang_as_iso639_1(x) or canonicalize_lang(x), mi.languages)))
+ langs = list(filter(None, (lang_as_iso639_1(x) or canonicalize_lang(x) for x in mi.languages)))
if langs:
create_sequence_property(dc, 'dc:language', langs, ordered=False)
diff --git a/src/calibre/ebooks/mobi/utils.py b/src/calibre/ebooks/mobi/utils.py
index 59bcc513d1..073d56dc74 100644
--- a/src/calibre/ebooks/mobi/utils.py
+++ b/src/calibre/ebooks/mobi/utils.py
@@ -647,4 +647,4 @@ def convert_color_for_font_tag(val):
def clamp(x):
return min(x, max(0, x), 1)
rgb = map(clamp, rgba[:3])
- return '#' + ''.join(map(lambda x:'%02x' % int(x * 255), rgb))
+ return '#' + ''.join(('%02x' % int(x * 255) for x in rgb))
diff --git a/src/calibre/ebooks/pdb/haodoo/reader.py b/src/calibre/ebooks/pdb/haodoo/reader.py
index 0bbca6a38f..29b7095c8d 100644
--- a/src/calibre/ebooks/pdb/haodoo/reader.py
+++ b/src/calibre/ebooks/pdb/haodoo/reader.py
@@ -60,9 +60,7 @@ class LegacyHeaderRecord:
fields = raw.lstrip().replace(b'\x1b\x1b\x1b', b'\x1b').split(b'\x1b')
self.title = fix_punct(fields[0].decode('cp950', 'replace'))
self.num_records = int(fields[1])
- self.chapter_titles = list(map(
- lambda x: fix_punct(x.decode('cp950', 'replace').rstrip('\x00')),
- fields[2:]))
+ self.chapter_titles = [fix_punct(x.decode('cp950', 'replace').rstrip('\x00')) for x in fields[2:]]
class UnicodeHeaderRecord:
@@ -72,9 +70,7 @@ class UnicodeHeaderRecord:
b'\x1b\x00').split(b'\x1b\x00')
self.title = fix_punct(fields[0].decode('utf_16_le', 'ignore'))
self.num_records = int(fields[1])
- self.chapter_titles = list(map(
- lambda x: fix_punct(x.decode('utf_16_le', 'replace').rstrip('\x00')),
- fields[2].split(b'\r\x00\n\x00')))
+ self.chapter_titles = [fix_punct(x.decode('utf_16_le', 'replace').rstrip('\x00')) for x in fields[2].split(b'\r\x00\n\x00')]
class Reader(FormatReader):
diff --git a/src/calibre/ebooks/pdf/render/gradients.py b/src/calibre/ebooks/pdf/render/gradients.py
index 6e9c1ae1fa..c042509aa8 100644
--- a/src/calibre/ebooks/pdf/render/gradients.py
+++ b/src/calibre/ebooks/pdf/render/gradients.py
@@ -79,7 +79,7 @@ class LinearGradientPattern(Dictionary):
matrix):
start = gradient.start()
stop = gradient.finalStop()
- stops = list(map(lambda x: [x[0], x[1].getRgbF()], gradient.stops()))
+ stops = [[x[0], x[1].getRgbF()] for x in gradient.stops()]
spread = gradient.spread()
if spread != gradient.PadSpread:
inv = matrix.inverted()[0]
diff --git a/src/calibre/gui2/dialogs/metadata_bulk.py b/src/calibre/gui2/dialogs/metadata_bulk.py
index c44076faf2..1bf8a3c016 100644
--- a/src/calibre/gui2/dialogs/metadata_bulk.py
+++ b/src/calibre/gui2/dialogs/metadata_bulk.py
@@ -660,10 +660,8 @@ class MetadataBulkDialog(QDialog, Ui_MetadataBulkDialog):
self.button_transform_publishers.clicked.connect(self.transform_publishers)
self.button_transform_series.clicked.connect(self.transform_series)
self.tag_map_rules = self.author_map_rules = self.publisher_map_rules = self.series_map_rules = ()
- tuple(map(lambda b: (b.clicked.connect(self.clear_transform_rules_for), b.setIcon(QIcon.ic('clear_left.png')), b.setToolTip(_(
- 'Clear the rules'))),
- (self.button_clear_tags_rules, self.button_clear_authors_rules, self.button_clear_publishers_rules)
- ))
+ tuple(((b.clicked.connect(self.clear_transform_rules_for), b.setIcon(QIcon.ic('clear_left.png')), b.setToolTip(_(
+ 'Clear the rules'))) for b in (self.button_clear_tags_rules, self.button_clear_authors_rules, self.button_clear_publishers_rules)))
self.update_transform_labels()
if starting_tab < 0:
starting_tab = gprefs.get('bulk_metadata_window_tab', 0)
diff --git a/src/calibre/gui2/dialogs/search.py b/src/calibre/gui2/dialogs/search.py
index 46c69e3412..7dad89f7d2 100644
--- a/src/calibre/gui2/dialogs/search.py
+++ b/src/calibre/gui2/dialogs/search.py
@@ -505,8 +505,7 @@ class SearchDialog(QDialog):
self.mc = '~'
else:
self.mc = '^'
- all, any, phrase, none = map(lambda x: str(x.text()),
- (self.all, self.any, self.phrase, self.none))
+ all, any, phrase, none = (str(x.text()) for x in (self.all, self.any, self.phrase, self.none))
all, any, none = map(self.tokens, (all, any, none))
phrase = phrase.strip()
all = ' and '.join(all)
diff --git a/src/calibre/gui2/dialogs/template_dialog_code_widget.py b/src/calibre/gui2/dialogs/template_dialog_code_widget.py
index 196eaab1ee..9a3ec98a58 100644
--- a/src/calibre/gui2/dialogs/template_dialog_code_widget.py
+++ b/src/calibre/gui2/dialogs/template_dialog_code_widget.py
@@ -59,7 +59,7 @@ class CodeEditor(QPlainTextEdit):
def line_number_area_width(self):
# get largest width of digits
fm = self.fontMetrics()
- self.number_width = max(map(lambda x:fm.horizontalAdvance(str(x)), range(10)))
+ self.number_width = max((fm.horizontalAdvance(str(x)) for x in range(10)))
digits = 1
limit = max(1, self.blockCount())
while limit >= 10:
diff --git a/src/calibre/gui2/preferences/columns.py b/src/calibre/gui2/preferences/columns.py
index 0ad9242d38..98a413d15f 100644
--- a/src/calibre/gui2/preferences/columns.py
+++ b/src/calibre/gui2/preferences/columns.py
@@ -107,9 +107,7 @@ class ConfigWidget(ConfigWidgetBase, Ui_Form):
self.opt_columns.verticalHeader().hide()
self.opt_columns.setRowCount(len(colmap))
- self.column_desc = dict(map(lambda x:(CreateCustomColumn.column_types[x]['datatype'],
- CreateCustomColumn.column_types[x]['text']),
- CreateCustomColumn.column_types))
+ self.column_desc = {CreateCustomColumn.column_types[x]['datatype']: CreateCustomColumn.column_types[x]['text'] for x in CreateCustomColumn.column_types}
for row, key in enumerate(colmap):
self.setup_row(row, key, row)
diff --git a/src/calibre/gui2/preferences/create_custom_column.py b/src/calibre/gui2/preferences/create_custom_column.py
index 6409b099ef..fcee648991 100644
--- a/src/calibre/gui2/preferences/create_custom_column.py
+++ b/src/calibre/gui2/preferences/create_custom_column.py
@@ -157,8 +157,7 @@ class CreateCustomColumn(QDialog):
ct = '*' + ct
self.orig_column_number = c['colnum']
self.orig_column_name = col
- column_numbers = dict(map(lambda x:(self.column_types[x]['datatype'], x),
- self.column_types))
+ column_numbers = {self.column_types[x]['datatype']: x for x in self.column_types}
self.column_type_box.setCurrentIndex(column_numbers[ct])
self.column_type_box.setEnabled(False)
diff --git a/src/calibre/gui2/preferences/look_feel.py b/src/calibre/gui2/preferences/look_feel.py
index 5567ac4aba..acbd7fdddf 100644
--- a/src/calibre/gui2/preferences/look_feel.py
+++ b/src/calibre/gui2/preferences/look_feel.py
@@ -236,7 +236,7 @@ class IdLinksEditor(Dialog):
def edit_rule(self, r=-1):
key = name = template = ''
if r > -1:
- key, name, template = map(lambda c: self.table.item(r, c).text(), range(3))
+ key, name, template = (self.table.item(r, c).text() for c in range(3))
d = IdLinksRuleEdit(key, name, template, self)
if d.exec() == QDialog.DialogCode.Accepted:
if r < 0:
diff --git a/src/calibre/gui2/preferences/texture_chooser.py b/src/calibre/gui2/preferences/texture_chooser.py
index a0f1ea55ca..3d04b6d52c 100644
--- a/src/calibre/gui2/preferences/texture_chooser.py
+++ b/src/calibre/gui2/preferences/texture_chooser.py
@@ -86,7 +86,7 @@ class TextureChooser(QDialog):
images = [{
'fname': ':'+os.path.basename(x),
'path': x,
- 'name': ' '.join(map(lambda s: s.capitalize(), os.path.splitext(os.path.basename(x))[0].split('_')))
+ 'name': ' '.join((s.capitalize() for s in os.path.splitext(os.path.basename(x))[0].split('_')))
} for x in glob.glob(I('textures/*.png'))] + [{
'fname': os.path.basename(x),
'path': x,
diff --git a/src/calibre/gui2/search_box.py b/src/calibre/gui2/search_box.py
index 7e03a0a88d..eeeccc6239 100644
--- a/src/calibre/gui2/search_box.py
+++ b/src/calibre/gui2/search_box.py
@@ -363,9 +363,7 @@ class SearchBoxMixin: # {{{
self.search.clear()
self.search.setMaximumWidth(self.width()-150)
self.action_focus_search = QAction(self)
- shortcuts = list(
- map(lambda x:str(x.toString(QKeySequence.SequenceFormat.PortableText)),
- QKeySequence.keyBindings(QKeySequence.StandardKey.Find)))
+ shortcuts = [str(x.toString(QKeySequence.SequenceFormat.PortableText)) for x in QKeySequence.keyBindings(QKeySequence.StandardKey.Find)]
shortcuts += ['/', 'Alt+S']
self.keyboard.register_shortcut('start search', _('Start search'),
default_keys=shortcuts, action=self.action_focus_search)
diff --git a/src/calibre/gui2/store/config/chooser/adv_search_builder.py b/src/calibre/gui2/store/config/chooser/adv_search_builder.py
index ca6129fddf..5a443320e6 100644
--- a/src/calibre/gui2/store/config/chooser/adv_search_builder.py
+++ b/src/calibre/gui2/store/config/chooser/adv_search_builder.py
@@ -73,8 +73,7 @@ class AdvSearchBuilderDialog(QDialog, Ui_Dialog):
self.mc = '='
else:
self.mc = '~'
- all, any, phrase, none = map(lambda x: str(x.text()),
- (self.all, self.any, self.phrase, self.none))
+ all, any, phrase, none = (str(x.text()) for x in (self.all, self.any, self.phrase, self.none))
all, any, none = map(self.tokens, (all, any, none))
phrase = phrase.strip()
all = ' and '.join(all)
diff --git a/src/calibre/gui2/store/search/adv_search_builder.py b/src/calibre/gui2/store/search/adv_search_builder.py
index c6442c89ec..91281a6512 100644
--- a/src/calibre/gui2/store/search/adv_search_builder.py
+++ b/src/calibre/gui2/store/search/adv_search_builder.py
@@ -80,8 +80,7 @@ class AdvSearchBuilderDialog(QDialog, Ui_Dialog):
self.mc = '='
else:
self.mc = '~'
- all, any, phrase, none = list(map(lambda x: str(x.text()),
- (self.all, self.any, self.phrase, self.none)))
+ all, any, phrase, none = [str(x.text()) for x in (self.all, self.any, self.phrase, self.none)]
all, any, none = list(map(self.tokens, (all, any, none)))
phrase = phrase.strip()
all = ' and '.join(all)
diff --git a/src/calibre/gui2/store/stores/mobileread/adv_search_builder.py b/src/calibre/gui2/store/stores/mobileread/adv_search_builder.py
index 8ea8dbea80..2c9781e9ce 100644
--- a/src/calibre/gui2/store/stores/mobileread/adv_search_builder.py
+++ b/src/calibre/gui2/store/stores/mobileread/adv_search_builder.py
@@ -73,8 +73,7 @@ class AdvSearchBuilderDialog(QDialog, Ui_Dialog):
self.mc = '='
else:
self.mc = '~'
- all, any, phrase, none = list(map(lambda x: type(u'')(x.text()),
- (self.all, self.any, self.phrase, self.none)))
+ all, any, phrase, none = [type(u'')(x.text()) for x in (self.all, self.any, self.phrase, self.none)]
all, any, none = list(map(self.tokens, (all, any, none)))
phrase = phrase.strip()
all = ' and '.join(all)
diff --git a/src/calibre/gui2/tweak_book/diff/view.py b/src/calibre/gui2/tweak_book/diff/view.py
index d7e487dc76..12e0735604 100644
--- a/src/calibre/gui2/tweak_book/diff/view.py
+++ b/src/calibre/gui2/tweak_book/diff/view.py
@@ -181,7 +181,7 @@ class TextBrowser(PlainTextEdit): # {{{
def calculate_metrics(self):
fm = self.fontMetrics()
- self.number_width = max(map(lambda x:fm.horizontalAdvance(str(x)), range(10)))
+ self.number_width = max((fm.horizontalAdvance(str(x)) for x in range(10)))
self.space_width = fm.horizontalAdvance(' ')
def show_context_menu(self, pos):
diff --git a/src/calibre/gui2/tweak_book/editor/text.py b/src/calibre/gui2/tweak_book/editor/text.py
index cab778533d..63b7c96a1f 100644
--- a/src/calibre/gui2/tweak_book/editor/text.py
+++ b/src/calibre/gui2/tweak_book/editor/text.py
@@ -282,7 +282,7 @@ class TextEdit(PlainTextEdit):
self.setFont(font)
self.highlighter.apply_theme(theme)
fm = self.fontMetrics()
- self.number_width = max(map(lambda x:fm.horizontalAdvance(str(x)), range(10)))
+ self.number_width = max((fm.horizontalAdvance(str(x)) for x in range(10)))
self.size_hint = QSize(self.expected_geometry[0] * fm.averageCharWidth(), self.expected_geometry[1] * fm.height())
self.highlight_color = theme_color(theme, 'HighlightRegion', 'bg')
self.highlight_cursor_line()
diff --git a/src/calibre/library/database2.py b/src/calibre/library/database2.py
index 03925d9d72..bce7e1f990 100644
--- a/src/calibre/library/database2.py
+++ b/src/calibre/library/database2.py
@@ -2119,7 +2119,7 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
# temporarily duplicating the categories lists.
taglist = {}
for c in categories.keys():
- taglist[c] = dict(map(lambda t:(icu_lower(t.name), t), categories[c]))
+ taglist[c] = {icu_lower(t.name): t for t in categories[c]}
muc = self.prefs.get('grouped_search_make_user_categories', [])
gst = self.prefs.get('grouped_search_terms', {})
diff --git a/src/calibre/srv/http_response.py b/src/calibre/srv/http_response.py
index 290e5f06cb..c91e71dc8f 100644
--- a/src/calibre/srv/http_response.py
+++ b/src/calibre/srv/http_response.py
@@ -69,7 +69,7 @@ def parse_multipart_byterange(buf, content_type): # {{{
if not cr.startswith('bytes '):
raise ValueError('Malformed Content-Range header in sub-part, no prefix')
try:
- start, stop = map(lambda x: int(x.strip()), cr.partition(' ')[-1].partition('/')[0].partition('-')[::2])
+ start, stop = (int(x.strip()) for x in cr.partition(' ')[-1].partition('/')[0].partition('-')[::2])
except Exception:
raise ValueError('Malformed Content-Range header in sub-part, failed to parse byte range')
content_length = stop - start + 1
diff --git a/src/calibre/srv/tests/auth.py b/src/calibre/srv/tests/auth.py
index 3580862472..290d537839 100644
--- a/src/calibre/srv/tests/auth.py
+++ b/src/calibre/srv/tests/auth.py
@@ -131,7 +131,7 @@ class TestAuth(BaseTest):
opts = Options(userdb=':memory:')
Data = namedtuple('Data', 'username')
with TemporaryDirectory() as base:
- l1, l2, l3 = map(lambda x: os.path.join(base, 'l' + x), '123')
+ l1, l2, l3 = (os.path.join(base, 'l' + x) for x in '123')
for l in (l1, l2, l3):
create_backend(l).close()
ctx = Handler((l1, l2, l3), opts).router.ctx
diff --git a/src/calibre/srv/tests/loop.py b/src/calibre/srv/tests/loop.py
index 4a01d7f3b2..773ce382d0 100644
--- a/src/calibre/srv/tests/loop.py
+++ b/src/calibre/srv/tests/loop.py
@@ -198,7 +198,7 @@ class LoopTest(BaseTest):
'Test serving over SSL'
address = '127.0.0.1'
with TemporaryDirectory('srv-test-ssl') as tdir:
- cert_file, key_file, ca_file = map(lambda x:os.path.join(tdir, x), 'cka')
+ cert_file, key_file, ca_file = (os.path.join(tdir, x) for x in 'cka')
create_server_cert(address, ca_file, cert_file, key_file, key_size=2048)
ctx = ssl.create_default_context(cafile=ca_file)
ctx.verify_flags |= ssl.VERIFY_X509_STRICT
diff --git a/src/calibre/srv/users.py b/src/calibre/srv/users.py
index 3a5f00e1b1..e10859a1a1 100644
--- a/src/calibre/srv/users.py
+++ b/src/calibre/srv/users.py
@@ -36,8 +36,8 @@ def parse_restriction(raw):
lr = r.get('library_restrictions', {})
if not isinstance(lr, dict):
lr = {}
- r['allowed_library_names'] = frozenset(map(lambda x: x.lower(), r.get('allowed_library_names', ())))
- r['blocked_library_names'] = frozenset(map(lambda x: x.lower(), r.get('blocked_library_names', ())))
+ r['allowed_library_names'] = frozenset((x.lower() for x in r.get('allowed_library_names', ())))
+ r['blocked_library_names'] = frozenset((x.lower() for x in r.get('blocked_library_names', ())))
r['library_restrictions'] = {k.lower(): v or '' for k, v in iteritems(lr)}
return r
diff --git a/src/calibre/test_build.py b/src/calibre/test_build.py
index e403522c37..494cbe9e7b 100644
--- a/src/calibre/test_build.py
+++ b/src/calibre/test_build.py
@@ -344,7 +344,7 @@ class BuildTest(unittest.TestCase):
# package. On non-frozen builds, it should just work because the
# hard-coded paths of the Qt installation should work. If they do not,
# then it is a distro problem.
- fmts = set(map(lambda x: x.data().decode('utf-8'), QImageReader.supportedImageFormats())) # no2to3
+ fmts = {x.data().decode('utf-8') for x in QImageReader.supportedImageFormats()} # no2to3
testf = {'jpg', 'png', 'svg', 'ico', 'gif', 'webp'}
self.assertEqual(testf.intersection(fmts), testf, "Qt doesn't seem to be able to load some of its image plugins. Available plugins: %s" % fmts)
data = P('images/blank.png', allow_user_override=False, data=True)
diff --git a/src/calibre/utils/matcher.py b/src/calibre/utils/matcher.py
index f9300de916..ee85d4a568 100644
--- a/src/calibre/utils/matcher.py
+++ b/src/calibre/utils/matcher.py
@@ -99,7 +99,7 @@ class Matcher:
w = [Worker(requests, results) for i in range(max(1, cpu_count()))]
[x.start() for x in w]
workers.extend(w)
- items = map(lambda x: normalize('NFC', str(x)), filter(None, items))
+ items = (normalize('NFC', str(x)) for x in filter(None, items))
self.items = items = tuple(items)
tasks = split(items, len(workers))
self.task_maps = [{j: i for j, (i, _) in enumerate(task)} for task in tasks]