Standardize on Black for Python code in mozilla-central.

Allow-list all Python code in tree for use with the black linter, and re-format all code in-tree accordingly.

To produce this patch I did all of the following:

1. Make changes to tools/lint/black.yml to remove include: stanza and update list of source extensions.

2. Run ./mach lint --linter black --fix

3. Make some ad-hoc manual updates to python/mozbuild/mozbuild/test/configure/test_configure.py -- it has some hard-coded line numbers that the reformat breaks.

4. Add a set of exclusions to black.yml. These will be deleted in a follow-up bug (1672023).


Differential Revision: https://phabricator.services.mozilla.com/D94045

components/style/gecko/regen_atoms.py

@@ -10,21 +10,33 @@ import sys
 
 from io import BytesIO
 
-GECKO_DIR = os.path.dirname(__file__.replace('\\', '/'))
+GECKO_DIR = os.path.dirname(__file__.replace("\\", "/"))
 sys.path.insert(0, os.path.join(os.path.dirname(GECKO_DIR), "properties"))
 
 import build
 
 
 # Matches lines like `GK_ATOM(foo, "foo", 0x12345678, true, nsStaticAtom, PseudoElementAtom)`.
-PATTERN = re.compile('^GK_ATOM\(([^,]*),[^"]*"([^"]*)",\s*(0x[0-9a-f]+),\s*[^,]*,\s*([^,]*),\s*([^)]*)\)',
-                     re.MULTILINE)
+PATTERN = re.compile(
+    '^GK_ATOM\(([^,]*),[^"]*"([^"]*)",\s*(0x[0-9a-f]+),\s*[^,]*,\s*([^,]*),\s*([^)]*)\)',
+    re.MULTILINE,
+)
 FILE = "include/nsGkAtomList.h"
 
 
 def map_atom(ident):
-    if ident in {"box", "loop", "match", "mod", "ref",
-                 "self", "type", "use", "where", "in"}:
+    if ident in {
+        "box",
+        "loop",
+        "match",
+        "mod",
+        "ref",
+        "self",
+        "type",
+        "use",
+        "where",
+        "in",
+    }:
         return ident + "_"
     return ident
 
@@ -42,7 +54,11 @@ class Atom:
         # or "InheritingAnonBox".
         self.atom_type = atom_type
 
-        if self.is_pseudo_element() or self.is_anon_box() or self.is_tree_pseudo_element():
+        if (
+            self.is_pseudo_element()
+            or self.is_anon_box()
+            or self.is_tree_pseudo_element()
+        ):
             self.pseudo_ident = (ident.split("_", 1))[1]
 
         if self.is_anon_box():
@@ -82,34 +98,42 @@ def collect_atoms(objdir):
     with open(path) as f:
         content = f.read()
         for result in PATTERN.finditer(content):
-            atoms.append(Atom(result.group(1), result.group(2), result.group(3),
-                              result.group(4), result.group(5)))
+            atoms.append(
+                Atom(
+                    result.group(1),
+                    result.group(2),
+                    result.group(3),
+                    result.group(4),
+                    result.group(5),
+                )
+            )
     return atoms
 
 
 class FileAvoidWrite(BytesIO):
     """File-like object that buffers output and only writes if content changed."""
+
     def __init__(self, filename):
         BytesIO.__init__(self)
         self.name = filename
 
     def write(self, buf):
         if isinstance(buf, str):
-            buf = buf.encode('utf-8')
+            buf = buf.encode("utf-8")
         BytesIO.write(self, buf)
 
     def close(self):
         buf = self.getvalue()
         BytesIO.close(self)
         try:
-            with open(self.name, 'rb') as f:
+            with open(self.name, "rb") as f:
                 old_content = f.read()
                 if old_content == buf:
                     print("{} is not changed, skip".format(self.name))
                     return
         except IOError:
             pass
-        with open(self.name, 'wb') as f:
+        with open(self.name, "wb") as f:
             f.write(buf)
 
     def __enter__(self):
@@ -120,45 +144,57 @@ class FileAvoidWrite(BytesIO):
             self.close()
 
 
-PRELUDE = '''
+PRELUDE = """
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // Autogenerated file created by components/style/gecko/regen_atoms.py.
 // DO NOT EDIT DIRECTLY
-'''[1:]
+"""[
+    1:
+]
 
-RULE_TEMPLATE = '''
+RULE_TEMPLATE = """
     ("{atom}") => {{{{
         #[allow(unsafe_code)] #[allow(unused_unsafe)]
         unsafe {{ $crate::string_cache::Atom::from_index_unchecked({index}) }}
     }}}};
-'''[1:]
+"""[
+    1:
+]
 
-MACRO_TEMPLATE = '''
+MACRO_TEMPLATE = """
 /// Returns a static atom by passing the literal string it represents.
 #[macro_export]
 macro_rules! atom {{
 {body}\
 }}
-'''
+"""
+
 
 def write_atom_macro(atoms, file_name):
     with FileAvoidWrite(file_name) as f:
         f.write(PRELUDE)
-        macro_rules = [RULE_TEMPLATE.format(atom=atom.value, name=atom.ident, index=i)
-                       for (i, atom) in enumerate(atoms)]
-        f.write(MACRO_TEMPLATE.format(body=''.join(macro_rules)))
+        macro_rules = [
+            RULE_TEMPLATE.format(atom=atom.value, name=atom.ident, index=i)
+            for (i, atom) in enumerate(atoms)
+        ]
+        f.write(MACRO_TEMPLATE.format(body="".join(macro_rules)))
 
 
 def write_pseudo_elements(atoms, target_filename):
     pseudos = []
     for atom in atoms:
-        if atom.type() == "nsCSSPseudoElementStaticAtom" or atom.type() == "nsCSSAnonBoxPseudoStaticAtom":
+        if (
+            atom.type() == "nsCSSPseudoElementStaticAtom"
+            or atom.type() == "nsCSSAnonBoxPseudoStaticAtom"
+        ):
             pseudos.append(atom)
 
-    pseudo_definition_template = os.path.join(GECKO_DIR, "pseudo_element_definition.mako.rs")
+    pseudo_definition_template = os.path.join(
+        GECKO_DIR, "pseudo_element_definition.mako.rs"
+    )
     print("cargo:rerun-if-changed={}".format(pseudo_definition_template))
     contents = build.render(pseudo_definition_template, PSEUDOS=pseudos)