def test_format_expressions(
expression: Expression, expected_clickhouse: str, expected_anonymized: str
) -> None:
visitor = ClickhouseExpressionFormatter()
anonymized_visitor = ClickHouseExpressionFormatterAnonymized()
assert expression.accept(visitor) == expected_clickhouse
assert expression.accept(anonymized_visitor) == expected_anonymized
def replace_in_expression(
body: Expression, replace_lookup: Mapping[str,
Expression]) -> Expression:
ret = body.transform(lambda exp: replace_lookup[exp.column_name]
if isinstance(exp, Column) and exp.column_name in
replace_lookup else exp)
return ret
def test_expand_aliases(
expression: Expression,
lookup: Mapping[str, Expression],
nested_resolution: bool,
expected: Expression,
) -> None:
assert (expression.accept(
AliasExpanderVisitor(lookup, [], nested_resolution)) == expected)
def test_translation(
mappings: TranslationMappers,
expression: Expression,
expected: ClickhouseExpression,
) -> None:
translator = SnubaClickhouseMappingTranslator(mappings)
translated = expression.accept(translator)
assert translated == expected
def test_transaction_translation(
expression: Expression, expected: ClickhouseExpression,
) -> None:
translator = SnubaClickhouseMappingTranslator(
transaction_translation_mappers.concat(null_function_translation_mappers)
)
translated = expression.accept(translator)
assert translated == expected
def test_default_translation(expression: Expression) -> None:
"""
Ensures that a translation that relies on the default translation rules
produces a deep copy of the original expression.
"""
translated = expression.accept(
SnubaClickhouseMappingTranslator(TranslationMappers()))
assert translated == expression
def _process_root(
expression: Expression,
subqueries: Mapping[str, SubqueryDraft],
alias_generator: AliasGenerator,
) -> Expression:
"""
Takes a root expression in the main query, runs the branch cutter
and pushes down the subexpressions.
"""
subexpressions = expression.accept(BranchCutter(alias_generator))
return _push_down_branches(subexpressions, subqueries, alias_generator)
def test_branch_cutter(expression: Expression, expected: SubExpression,
main_expr: MainQueryExpression) -> None:
def alias_generator() -> Generator[str, None, None]:
i = 0
while True:
i += 1
yield f"_snuba_gen_{i}"
subexpression = expression.accept(BranchCutter(alias_generator()))
assert subexpression == expected
assert subexpression.cut_branch(alias_generator()) == main_expr
def test_escaping(expression: Expression, expected: str) -> None:
visitor = ClickhouseExpressionFormatter()
assert expression.accept(visitor) == expected
def test_format_expressions(expression: Expression, expected_clickhouse: str,
expected_tracing: TExpression) -> None:
visitor = ClickhouseExpressionFormatter()
assert expression.accept(visitor) == expected_clickhouse
assert expression.accept(TracingExpressionFormatter()) == expected_tracing
def transform_aggregate_functions_with_mismatched_nullable_parameters(
exp: Expression, ) -> Expression:
if (isinstance(exp, FunctionCall)
and exp.function_name in AGGREGATION_FUNCTIONS):
return exp.transform(cast_column_to_nullable)
return exp
