Use correct quotes regex in capitalization formatter

Author: DanielNoord

pydocstringformatter/_formatting/formatters_default.py

@@ -44,7 +44,9 @@ class CapitalizeFirstLetterFormatter(StringFormatter):
     """Capitalize the first letter of the docstring if appropriate."""
 
     name = "capitalize-first-letter"
-    first_letter_re = re.compile(r"""['"]{1,3}\s*(\w)""", re.DOTALL)
+    first_letter_re = re.compile(
+        StringAndQuotesFormatter.quotes_regex.pattern + r"""\s*(\w)""", re.DOTALL
+    )
 
     def treat_string(self, tokeninfo: tokenize.TokenInfo, _: int) -> str:
         new_string = None

tests/data/format/capitalization_first_letter/letter_after_quote.py

@@ -0,0 +1,11 @@
+def a(self):
+    "'a.m.' or 'p.m.'"
+
+def b(self):
+    """'a.m.' or 'p.m.'"""
+
+def c(self):
+    "'''a.m.''' or 'p.m.'"
+
+def d(self):
+    """'''a.m.''' or 'p.m.'"""

tests/data/format/capitalization_first_letter/letter_after_quote.py.out

@@ -0,0 +1,11 @@
+def a(self):
+    """'a.m.' or 'p.m.'."""
+
+def b(self):
+    """'a.m.' or 'p.m.'."""
+
+def c(self):
+    """'''a.m.''' or 'p.m.'."""
+
+def d(self):
+    """'''a.m.''' or 'p.m.'."""

tests/data/format/quotes_type/mix_with_double_at_start.py.out

@@ -1,5 +1,5 @@
 def a(self):
-    """'A.m.' or 'p.m.'."""
+    """'a.m.' or 'p.m.'."""
 
 def b(self):
     """'a.m.' or 'p.m.'."""

tests/data/format/quotes_type/mix_with_single_at_start.py.out

@@ -1,5 +1,5 @@
 def a(self):
-    """"A.m." or "p.m."."""
+    """"a.m." or "p.m."."""
 
 def b(self):
     """"a.m." or "p.m."."""