fix: parenthesize multi-word LIKE patterns, raise on invalid fulltext/fuzzy signatures

- LIKE '%gaming laptop%' now generates @title:(*gaming laptop*) to prevent
  token leaking across fields in Dialect 2
- fulltext(title) and fuzzy(title) with < 2 args now raise ValueError
  instead of silently dropping the predicate
- Update existing test expectation for insufficient args
- Add 3 new tests (379 total)

Author: nkanu17

sql_redis/parser.py

@@ -980,6 +980,12 @@ def _add_function_condition(
         func_name = expression.name.upper()
         args = expression.expressions
 
+        if func_name in ("FULLTEXT", "FUZZY") and len(args) < 2:
+            raise ValueError(
+                f"{func_name.lower()}() requires at least 2 arguments: "
+                f"{func_name.lower()}(field, value), got {len(args)}."
+            )
+
         if func_name == "FULLTEXT" and len(args) >= 2:
             field_name = args[0].name if isinstance(args[0], exp.Column) else None
             value = self._extract_literal_value(args[1])

sql_redis/query_builder.py

@@ -125,6 +125,12 @@ def build_text_condition(
             parts = value.split("%")
             escaped_parts = [self._escape_fulltext_term(p) for p in parts]
             search_value = "*".join(escaped_parts)
+            # If the non-wildcard portion contains spaces, wrap in parens
+            # so all tokens stay scoped to the field (e.g. '%gaming laptop%'
+            # → *gaming laptop* needs grouping to avoid token leaking).
+            non_wildcard = value.strip("%")
+            if " " in non_wildcard:
+                search_value = f"({search_value})"
         elif operator == "FUZZY":
             # Escape special chars before wrapping with % markers
             escaped = self._escape_fulltext_term(value)

tests/test_query_builder.py

@@ -427,6 +427,12 @@ def test_suffix_negated(self):
         result = builder.build_text_condition("title", "LIKE", "%phone", negated=True)
         assert result == "-@title:*phone"
 
+    def test_infix_multiword_grouped(self):
+        """LIKE '%multi word%' groups tokens in parentheses."""
+        builder = QueryBuilder()
+        result = builder.build_text_condition("title", "LIKE", "%gaming laptop%")
+        assert result == "@title:(*gaming laptop*)"
+
 
 class TestQueryBuilderORInText:
     """Tests for OR/union within text field searches."""

tests/test_sql_parser.py

@@ -622,12 +622,10 @@ def test_parse_fulltext_non_column_first_arg(self):
         assert len(result.conditions) == 0
 
     def test_parse_fulltext_insufficient_args(self):
-        """Parse fulltext with insufficient arguments."""
+        """Parse fulltext with insufficient arguments raises ValueError."""
         parser = SQLParser()
-        result = parser.parse("SELECT * FROM products WHERE fulltext(title)")
-
-        # Only 1 arg, needs >= 2 - condition skipped
-        assert len(result.conditions) == 0
+        with pytest.raises(ValueError, match="requires at least 2 arguments"):
+            parser.parse("SELECT * FROM products WHERE fulltext(title)")
 
     def test_parse_geo_distance_no_args(self):
         """Parse geo_distance with no arguments in comparison."""
@@ -897,3 +895,15 @@ def test_fulltext_invalid_inorder_raises(self):
             parser.parse(
                 "SELECT * FROM idx WHERE fulltext(title, 'hello world', 0, 'yes')"
             )
+
+    def test_fulltext_no_value_raises(self):
+        """fulltext() with only field arg raises ValueError."""
+        parser = SQLParser()
+        with pytest.raises(ValueError, match="requires at least 2 arguments"):
+            parser.parse("SELECT * FROM idx WHERE fulltext(title)")
+
+    def test_fuzzy_no_value_raises(self):
+        """fuzzy() with only field arg raises ValueError."""
+        parser = SQLParser()
+        with pytest.raises(ValueError, match="requires at least 2 arguments"):
+            parser.parse("SELECT * FROM idx WHERE fuzzy(title)")