Improve Python 2 only syntax detection (GH-2592)

[etc/vim.git] / src / black / strings.py

diff --git a/src/black/strings.py b/src/black/strings.py
index 5b443ddebc9e7e662b469b2c2717052ff2dcbf99..d7b6c240e80215ef1c268634433074d82e4c5aeb 100644 (file)
--- a/src/black/strings.py
+++ b/src/black/strings.py
@@ -87,7 +87,7 @@ def get_string_prefix(string: str) -> str:
     prefix = ""
     prefix_idx = 0
     while string[prefix_idx] in STRING_PREFIX_CHARS:
     prefix = ""
     prefix_idx = 0
     while string[prefix_idx] in STRING_PREFIX_CHARS:

-        prefix += string[prefix_idx].lower()
+        prefix += string[prefix_idx]

         prefix_idx += 1
 
     return prefix
         prefix_idx += 1
 
     return prefix


@@ -190,9 +190,9 @@ def normalize_string_quotes(s: str) -> str:
     if "f" in prefix.casefold():
         matches = re.findall(
             r"""
     if "f" in prefix.casefold():
         matches = re.findall(
             r"""

-            (?:[^{]|^)\{  # start of the string or a non-{ followed by a single {
+            (?:(?<!\{)|^)\{  # start of the string or a non-{ followed by a single {

                 ([^{].*?)  # contents of the brackets except if begins with {{
                 ([^{].*?)  # contents of the brackets except if begins with {{

-            \}(?:[^}]|$)  # A } followed by end of the string or a non-}
+            \}(?:(?!\})|$)  # A } followed by end of the string or a non-}

             """,
             new_body,
             re.VERBOSE,
             """,
             new_body,
             re.VERBOSE,