| # Specify analysis options. | 
 | # | 
 | # Until there are meta linter rules, each desired lint must be explicitly enabled. | 
 | # See: https://github.com/dart-lang/linter/issues/288 | 
 | # | 
 | # For a list of lints, see: http://dart-lang.github.io/linter/lints/ | 
 | # See the configuration guide for more | 
 | # https://github.com/dart-lang/sdk/tree/master/pkg/analyzer#configuring-the-analyzer | 
 | # | 
 | # NOTE: Please keep this file in sync with | 
 | # https://github.com/flutter/flutter/blob/master/analysis_options.yaml | 
 |  | 
 | analyzer: | 
 |   language: | 
 |     enableStrictCallChecks: true | 
 |     enableSuperMixins: true | 
 |     enableAssertInitializer: true | 
 |   strong-mode: | 
 |     implicit-dynamic: false | 
 |   errors: | 
 |     # treat missing required parameters as a warning (not a hint) | 
 |     missing_required_param: warning | 
 |     # treat missing returns as a warning (not a hint) | 
 |     missing_return: warning | 
 |     # allow having TODOs in the code | 
 |     todo: ignore | 
 |   exclude: | 
 |     - 'bin/cache/**' | 
 |     # the following two are relative to the stocks example and the flutter package respectively | 
 |     # see https://github.com/dart-lang/sdk/issues/28463 | 
 |     - 'lib/i18n/stock_messages_*.dart' | 
 |     - 'lib/src/http/**' | 
 |  | 
 | linter: | 
 |   rules: | 
 |     # these rules are documented on and in the same order as | 
 |     # the Dart Lint rules page to make maintenance easier | 
 |     # http://dart-lang.github.io/linter/lints/ | 
 |  | 
 |     # === error rules === | 
 |     - avoid_empty_else | 
 |     - avoid_slow_async_io | 
 |     - cancel_subscriptions | 
 |     # - close_sinks # https://github.com/flutter/flutter/issues/5789 | 
 |     # - comment_references # blocked on https://github.com/dart-lang/dartdoc/issues/1153 | 
 |     - control_flow_in_finally | 
 |     - empty_statements | 
 |     - hash_and_equals | 
 |     # - invariant_booleans # https://github.com/flutter/flutter/issues/5790 | 
 |     - iterable_contains_unrelated_type | 
 |     - list_remove_unrelated_type | 
 |     # - literal_only_boolean_expressions # https://github.com/flutter/flutter/issues/5791 | 
 |     - no_adjacent_strings_in_list | 
 |     - no_duplicate_case_values | 
 |     - test_types_in_equals | 
 |     - throw_in_finally | 
 |     - unrelated_type_equality_checks | 
 |     - valid_regexps | 
 |  | 
 |     # === style rules === | 
 |     - always_declare_return_types | 
 |     # - always_put_control_body_on_new_line | 
 |     - always_require_non_null_named_parameters | 
 |     - always_specify_types | 
 |     - annotate_overrides | 
 |     # - avoid_annotating_with_dynamic # not yet tested | 
 |     - avoid_as | 
 |     # - avoid_catches_without_on_clauses # not yet tested | 
 |     # - avoid_catching_errors # not yet tested | 
 |     # - avoid_classes_with_only_static_members # not yet tested | 
 |     # - avoid_function_literals_in_foreach_calls # not yet tested | 
 |     - avoid_init_to_null | 
 |     - avoid_null_checks_in_equality_operators | 
 |     # - avoid_positional_boolean_parameters # not yet tested | 
 |     - avoid_return_types_on_setters | 
 |     # - avoid_returning_null # not yet tested | 
 |     # - avoid_returning_this # not yet tested | 
 |     # - avoid_setters_without_getters # not yet tested | 
 |     # - avoid_types_on_closure_parameters # not yet tested | 
 |     - await_only_futures | 
 |     - camel_case_types | 
 |     # - cascade_invocations # not yet tested | 
 |     # - constant_identifier_names # https://github.com/dart-lang/linter/issues/204 | 
 |     - directives_ordering | 
 |     - empty_catches | 
 |     - empty_constructor_bodies | 
 |     - implementation_imports | 
 |     # - join_return_with_assignment # not yet tested | 
 |     - library_names | 
 |     - library_prefixes | 
 |     - non_constant_identifier_names | 
 |     # - omit_local_variable_types # opposite of always_specify_types | 
 |     # - one_member_abstracts # too many false positives | 
 |     # - only_throw_errors # https://github.com/flutter/flutter/issues/5792 | 
 |     - overridden_fields | 
 |     - package_api_docs | 
 |     - package_prefixed_library_names | 
 |     # - parameter_assignments # we do this commonly | 
 |     - prefer_adjacent_string_concatenation | 
 |     - prefer_collection_literals | 
 |     # - prefer_conditional_assignment # not yet tested | 
 |     - prefer_const_constructors | 
 |     # - prefer_constructors_over_static_methods # not yet tested | 
 |     - prefer_contains | 
 |     - prefer_equal_for_default_values | 
 |     # - prefer_expression_function_bodies # conflicts with https://github.com/flutter/flutter/wiki/Style-guide-for-Flutter-repo#consider-using--for-short-functions-and-methods | 
 |     # - prefer_final_fields # https://github.com/dart-lang/linter/issues/506 | 
 |     - prefer_final_locals | 
 |     # - prefer_foreach # not yet tested | 
 |     # - prefer_function_declarations_over_variables # not yet tested | 
 |     - prefer_initializing_formals | 
 |     # - prefer_interpolation_to_compose_strings # not yet tested | 
 |     - prefer_is_empty | 
 |     - prefer_is_not_empty | 
 |     - prefer_void_to_null | 
 |     # - recursive_getters # https://github.com/dart-lang/linter/issues/452 | 
 |     - slash_for_doc_comments | 
 |     - sort_constructors_first | 
 |     - sort_unnamed_constructors_first | 
 |     - super_goes_last | 
 |     # - type_annotate_public_apis # subset of always_specify_types | 
 |     - type_init_formals | 
 |     # - unawaited_futures # https://github.com/flutter/flutter/issues/5793 | 
 |     - unnecessary_brace_in_string_interps | 
 |     - unnecessary_const | 
 |     - unnecessary_getters_setters | 
 |     # - unnecessary_lambdas # https://github.com/dart-lang/linter/issues/498 | 
 |     - unnecessary_new | 
 |     - unnecessary_null_aware_assignments | 
 |     - unnecessary_null_in_if_null_operators | 
 |     # - unnecessary_overrides # https://github.com/dart-lang/linter/issues/626 and https://github.com/dart-lang/linter/issues/627 | 
 |     - unnecessary_statements | 
 |     - unnecessary_this | 
 |     - use_rethrow_when_possible | 
 |     # - use_setters_to_change_properties # not yet tested | 
 |     # - use_string_buffers # https://github.com/dart-lang/linter/pull/664 | 
 |     # - use_to_and_as_if_applicable # has false positives, so we prefer to catch this by code-review | 
 |  | 
 |     # === pub rules === | 
 |     - package_names |