fix dialog selector, add test

src/app/routes.py

@@ -47,15 +47,22 @@ def fluff_results():
     # dialect must be a dialect label for `load_raw_dialect`. VALID_DIALECTS is a
     # dictionary of dialect labels to dialect names. If we have a name, we need to
     # get the label.
+    #
+    # However, the frontend logic runs on dialect names, so we need to convert the
+    # label back to a name for the frontend.
     dialect = request.args["dialect"]
     if dialect in VALID_DIALECTS.values():
-        dialect = next(
+        dialect_name = dialect
+        dialect_label = next(
             label for label, name in VALID_DIALECTS.items() if name == dialect
         )
+    else:
+        dialect_label = dialect
+        dialect_name = VALID_DIALECTS[dialect]
 
     try:
-        linted = lint(sql, dialect=dialect)
-        fixed_sql = fix(sql, dialect=dialect)
+        linted = lint(sql, dialect=dialect_label)
+        fixed_sql = fix(sql, dialect=dialect_label)
     except RuntimeError as e:
         linted = [
             {
@@ -70,7 +77,7 @@ def fluff_results():
         "index.html",
         results=True,
         sql=sql,
-        dialect=dialect,
+        dialect=dialect_name,
         lint_errors=linted,
         fixed_sql=fixed_sql,
     )

test/test_app.py

@@ -39,7 +39,7 @@ def test_post_redirect(client):
 @pytest.mark.parametrize("dialect", ["sparksql", "Apache Spark SQL"])
 def test_results_no_errors(client, dialect):
     """Test that the results is good to go when there is no error.
-    
+
     Parameterized dialect asserts that either the formatted name or label can be used
     as the dialect parameter.
     """
@@ -50,6 +50,14 @@ def test_results_no_errors(client, dialect):
     assert "fixed sql" in html
     assert "select * from table" in html
 
+    # Test that the dialect is correctly selected in the results page.
+    selected_dialect = (
+        BeautifulSoup(html, "html.parser")
+        .find("select", {"id": "sql_dialect"})
+        .find("option", {"selected": "selected"})
+    )
+    assert selected_dialect.text.strip() == "apache spark sql"
+
 
 def test_results_some_errors(client):
     """Test that the results is good to go with one obvious error."""