Handle arbitrary amount of backslashes preceding the quote char

Tests for this were added additionally

2 files changed, 15 insertions, 11 deletions

diff --git a/bot/exts/info/doc/_parsing.py b/bot/exts/info/doc/_parsing.py
index fc38ff82a..57c991ae0 100644
--- a/bot/exts/info/doc/_parsing.py
+++ b/bot/exts/info/doc/_parsing.py
@@ -46,15 +46,6 @@ _BRACKET_PAIRS = {
 }
 
 
-def _is_closing_quote(search_string: str, index: int) -> bool:
-    """Check whether the quote at `index` inside `search_string` can be a closing quote."""
-    if search_string[index - 1] != "\\":
-        return True  # The quote is not escaped.
-    elif search_string[index - 2] == "\\":
-        return True
-    return False
-
-
 def _split_parameters(parameters_string: str) -> Iterator[str]:
     """
     Split parameters of a signature into individual parameter strings on commas.
@@ -70,9 +61,15 @@ def _split_parameters(parameters_string: str) -> Iterator[str]:
         if character in {"'", '"'}:
             # Skip everything inside of strings, regardless of the depth.
             quote_character = character  # The closing quote must equal the opening quote.
-            for index, character in enumerated_string:
-                if character == quote_character and _is_closing_quote(parameters_string, index):
+            preceding_backslashes = 0
+            for _, character in enumerated_string:
+                # If an odd number of backslashes precedes the quote, it was escaped.
+                if character == quote_character and not preceding_backslashes % 2:
                     break
+                if character == "\\":
+                    preceding_backslashes += 1
+                else:
+                    preceding_backslashes = 0
 
         elif current_search is None:
             if (current_search := _BRACKET_PAIRS.get(character)) is not None:
diff --git a/tests/bot/exts/info/doc/test_parsing.py b/tests/bot/exts/info/doc/test_parsing.py
index f302b38fc..1663d8491 100644
--- a/tests/bot/exts/info/doc/test_parsing.py
+++ b/tests/bot/exts/info/doc/test_parsing.py
@@ -42,6 +42,13 @@ class SignatureSplitter(TestCase):
         )
         self._run_tests(test_cases)
 
+    def test_quote_escaped(self):
+        test_cases = (
+            (r"'\',','\\',0", [r"'\','", r"'\\'", "0"]),
+            (r"'0\',0\\\'\\',0", [r"'0\',0\\\'\\'", "0"]),
+        )
+        self._run_tests(test_cases)
+
     def test_real_signatures(self):
         test_cases = (
             ("start, stop[, step]", ["start", " stop[, step]"]),