lint: Migrate typing.Text check to semgrep.

Signed-off-by: Anders Kaseorg <anders@zulip.com>

tools/lib/gitlint-rules.py

@@ -1,5 +1,5 @@
 import re
-from typing import List, Text
+from typing import List
 
 from gitlint.git import GitCommit
 from gitlint.options import StrOption
@@ -85,7 +85,7 @@ imperative_forms = [
 imperative_forms.sort()
 
 
-def head_binary_search(key: Text, words: List[str]) -> str:
+def head_binary_search(key: str, words: List[str]) -> str:
     """ Find the imperative mood version of `word` by looking at the first
     3 characters. """
 
@@ -124,7 +124,7 @@ class ImperativeMood(LineRule):
     error_msg = ('The first word in commit title should be in imperative mood '
                  '("{word}" -> "{imperative}"): "{title}"')
 
-    def validate(self, line: Text, commit: GitCommit) -> List[RuleViolation]:
+    def validate(self, line: str, commit: GitCommit) -> List[RuleViolation]:
         violations = []
 
         # Ignore the section tag (ie `<section tag>: <message body>.`)
@@ -152,7 +152,7 @@ class TitleMatchRegexAllowException(LineRule):
     target = CommitMessageTitle
     options_spec = [StrOption('regex', ".*", "Regex the title should match")]
 
-    def validate(self, title: Text, commit: GitCommit) -> List[RuleViolation]:
+    def validate(self, title: str, commit: GitCommit) -> List[RuleViolation]:
 
         regex = self.options['regex'].value
         pattern = re.compile(regex, re.UNICODE)

tools/lib/template_parser.py

@@ -1,4 +1,4 @@
-from typing import Callable, List, Optional, Text
+from typing import Callable, List, Optional
 
 
 class FormattedException(Exception):
@@ -306,7 +306,7 @@ OPTIONAL_CLOSING_TAGS = [
     'stop',
 ]
 
-def is_self_closing_html_tag(s: Text, tag: Text) -> bool:
+def is_self_closing_html_tag(s: str, tag: str) -> bool:
     if s.endswith('/>'):
         if tag in OPTIONAL_CLOSING_TAGS:
             return True

tools/linter_lib/custom_check.py

@@ -360,16 +360,6 @@ python_rules = RuleList(
          'bad_lines': ['desc: Optional[Text] = models.TextField()',
                        'stream: Optional[Stream] = models.ForeignKey(Stream, on_delete=CASCADE)'],
          },
-        {'pattern': r'[\s([]Text([^\s\w]|$)',
-         'exclude': {
-             # We are likely to want to keep these dirs Python 2+3 compatible,
-             # since the plan includes extracting them to a separate project eventually.
-             'tools/lib',
-             # TODO: Update our migrations from Text->str.
-             'zerver/migrations/',
-         },
-         'description': "Now that we're a Python 3 only codebase, we don't need to use typing.Text. Please use str instead.",
-         },
         {'pattern': 'exit[(]1[)]',
          'include_only': {"/management/commands/"},
          'description': 'Raise CommandError to exit with failure in management commands',

tools/semgrep.yml

@@ -133,3 +133,9 @@ rules:
     pattern: eval
     severity: ERROR
     message: "Do not use eval under any circumstances; consider json.loads instead"
+
+  - id: typing-text
+    languages: [python]
+    pattern: typing.Text
+    severity: ERROR
+    message: "Use str instead of typing.Text"

zerver/migrations/0032_verify_all_medium_avatar_images.py

@@ -1,5 +1,4 @@
 import hashlib
-from typing import Text
 from unittest.mock import patch
 
 from django.conf import settings
@@ -18,7 +17,7 @@ from zerver.models import UserProfile
 # from zerver.lib.upload (which would pretty annoying, but would be a
 # pain) and just using the current version, which doesn't work
 # since we rearranged the avatars in Zulip 1.6.
-def patched_user_avatar_path(user_profile: UserProfile) -> Text:
+def patched_user_avatar_path(user_profile: UserProfile) -> str:
     email = user_profile.email
     user_key = email.lower() + settings.AVATAR_SALT
     return make_safe_digest(user_key, hashlib.sha1)