fix: support else in for loops (#551)

CHANGELOG.md

@@ -4,6 +4,10 @@ All notable changes to this project will be documented in this file.
 
 ## [Unreleased]
 
+### Bug Fixes
+
+-   `{% for %}...{% else %}...{% endfor %}` loops are now supported. Previously, a BracketError was raised if a `for` loop included an `else` tag ([#549](https://github.com/tconbeer/sqlfmt/issues/549) - thank you, [@yassun7010](https://github.com/yassun7010)!).
+
 ## [0.21.1] - 2023-12-19
 
 ### Bug Fixes

src/sqlfmt/node_manager.py

@@ -77,8 +77,11 @@ def raise_on_mismatched_jinja_tags(self, token: Token, start_tag: Node) -> None:
         closes start_tag
         """
         try:
-            if any(s in token.token.lower() for s in ["endif", "else", "elif"]):
-                if not any(s in start_tag.value for s in ["if", "else"]):
+            if "endif" in token.token.lower():
+                if not any(s in start_tag.value for s in ["if", "elif", "else"]):
+                    raise ValueError
+            elif "endfor" in token.token.lower():
+                if not any(s in start_tag.value for s in ["for", "else"]):
                     raise ValueError
             else:
                 end_text, _ = re.subn(r"[{}%\-\s]", "", token.token.lower())

tests/data/unformatted/133_for_else.sql

@@ -0,0 +1,7 @@
+{% for i in range(5) %}
+    select 1
+{% else %}
+    select 2
+{% endfor %}
+)))))__SQLFMT_OUTPUT__(((((
+{% for i in range(5) %} select 1{% else %} select 2 {% endfor %}

tests/functional_tests/test_general_formatting.py

@@ -49,6 +49,7 @@
         "unformatted/129_duckdb_joins.sql",
         "unformatted/130_athena_data_types.sql",
         "unformatted/131_assignment_statement.sql",
+        "unformatted/133_for_else.sql",
         "unformatted/200_base_model.sql",
         "unformatted/201_basic_snapshot.sql",
         "unformatted/202_unpivot_macro.sql",