Utilities/Sphinx: Use f-strings in cmake.py

Port all uses of old-style % string formatting to use f-strings. These
are generally more readable (and tend to be shorter as well).

Although this requires Python 3.6 or later, that should be available
'stock' on most or all platforms still under support, and besides, we
were already using f-strings in some places.

Utilities/Sphinx/cmake.py

@@ -106,7 +106,7 @@ class CMakeModule(Directive):
     def run(self):
         settings = self.state.document.settings
         if not settings.file_insertion_enabled:
-            raise self.warning('"%s" directive disabled.' % self.name)
+            raise self.warning(f'{self.name!r} directive disabled.')
 
         env = self.state.document.settings.env
         rel_path, path = env.relfn2path(self.arguments[0])
@@ -117,13 +117,12 @@ class CMakeModule(Directive):
             settings.record_dependencies.add(path)
             f = io.FileInput(source_path=path, encoding=encoding,
                              error_handler=e_handler)
-        except UnicodeEncodeError as error:
-            msg = ('Problems with "%s" directive path:\n'
-                   'Cannot encode input file path "%s" '
-                   '(wrong locale?).' % (self.name, path))
+        except UnicodeEncodeError:
+            msg = (f'Problems with {self.name!r} directive path:\n'
+                   f'Cannot encode input file path {path!r} (wrong locale?).')
             raise self.severe(msg)
         except IOError as error:
-            msg = 'Problems with "%s" directive path:\n%s.' % (self.name, error)
+            msg = f'Problems with {self.name!r} directive path:\n{error}.'
             raise self.severe(msg)
         raw_lines = f.read().splitlines()
         f.close()
@@ -143,7 +142,7 @@ class CMakeModule(Directive):
                 # Line mode: check for .rst start (bracket or line)
                 m = self.re_start.match(line)
                 if m:
-                    rst = ']%s]' % m.group('eq')
+                    rst = f']{m.group("eq")}]'
                     line = ''
                 elif line == '#.rst:':
                     rst = '#'
@@ -158,8 +157,8 @@ class CMakeModule(Directive):
                     line = ''
             lines.append(line)
         if rst is not None and rst != '#':
-            raise self.warning('"%s" found unclosed bracket "#[%s[.rst:" in %s' %
-                               (self.name, rst[1:-1], path))
+            raise self.warning(f'{self.name!r} found unclosed bracket '
+                               f'"#[{rst[1:-1]}[.rst:" in {path!r}')
         self.state_machine.insert_input(lines, path)
         return []
 
@@ -168,7 +167,7 @@ class _cmake_index_entry:
         self.desc = desc
 
     def __call__(self, title, targetid, main = 'main'):
-        return ('pair', u'%s ; %s' % (self.desc, title), targetid, main, None)
+        return ('pair', f'{self.desc} ; {title}', targetid, main, None)
 
 _cmake_index_objs = {
     'command':    _cmake_index_entry('command'),
@@ -244,7 +243,7 @@ class CMakeTransform(Transform):
                     if m:
                         title = m.group(1)
                 targetname = title
-            targetid = '%s:%s' % (objtype, targetname)
+            targetid = f'{objtype}:{targetname}'
             targetnode = nodes.target('', '', ids=[targetid])
             self.document.note_explicit_target(targetnode)
             self.document.insert(0, targetnode)
@@ -274,7 +273,7 @@ class CMakeObject(ObjectDescription):
             targetname = self.targetname
         else:
             targetname = name
-        targetid = '%s:%s' % (self.objtype, targetname)
+        targetid = f'{self.objtype}:{targetname}'
         if targetid not in self.state.document.ids:
             signode['names'].append(targetid)
             signode['ids'].append(targetid)
@@ -513,11 +512,11 @@ class CMakeXRefRole(CMakeReferenceRole[XRefRole]):
         elif typ == 'cmake:genex':
             m = CMakeXRefRole._re_genex.match(text)
             if m:
-                text = '%s <%s>' % (text, m.group(1))
+                text = f'{text} <{m.group(1)}>'
         elif typ == 'cmake:guide':
             m = CMakeXRefRole._re_guide.match(text)
             if m:
-                text = '%s <%s>' % (m.group(2), text)
+                text = f'{m.group(2)} <{text}>'
         return super().__call__(typ, rawtext, text, *args, **kwargs)
 
     # We cannot insert index nodes using the result_nodes method
@@ -561,9 +560,9 @@ class CMakeXRefTransform(Transform):
                 # Index signature references to their parent command.
                 objname = objname.split('(')[0].lower()
 
-            targetnum = env.new_serialno('index-%s:%s' % (objtype, objname))
+            targetnum = env.new_serialno(f'index-{objtype}:{objname}')
 
-            targetid = 'index-%s-%s:%s' % (targetnum, objtype, objname)
+            targetid = f'index-{targetnum}-{objtype}:{objname}'
             targetnode = nodes.target('', '', ids=[targetid])
             self.document.note_explicit_target(targetnode)