ClickHouse/tests/integration
2020-11-11 19:27:37 +08:00
..
helpers Add awesome test for fetch 2020-10-27 15:24:10 +03:00
test_access_control_on_cluster Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_adaptive_granularity Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_adaptive_granularity_different_settings Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_adaptive_granularity_replicated Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_aggregation_memory_efficient Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_allowed_client_hosts Merge pull request #13156 from azat/cluster-secure 2020-09-17 17:11:00 +03:00
test_allowed_url_from_config Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_alter_codec Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_alter_on_mixed_type_cluster Remove cluster type check during alter 2020-10-16 14:59:58 +03:00
test_always_fetch_merged Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_asynchronous_metric_log_table Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_atomic_drop_table enable more tests 2020-09-22 17:29:09 +03:00
test_attach_without_checksums Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_authentication Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_backup_restore enable more tests 2020-09-22 17:29:09 +03:00
test_backup_with_other_granularity enable more tests 2020-09-22 17:29:09 +03:00
test_backward_compatibility Merge remote-tracking branch 'upstream/master' into HEAD 2020-09-16 21:07:35 +03:00
test_block_structure_mismatch Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_check_table Merge remote-tracking branch 'upstream/master' into HEAD 2020-09-16 21:07:35 +03:00
test_cleanup_dir_after_bad_zk_conn Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_cluster_all_replicas Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_cluster_copier Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_compression_nested_columns More tests 2020-09-22 16:16:42 +03:00
test_concurrent_queries_for_all_users_restriction Add max_concurrent_queries_for_all_users setting 2020-10-19 15:51:28 +01:00
test_concurrent_queries_for_user_restriction Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_concurrent_ttl_merges Add missed file 2020-10-28 10:01:57 +03:00
test_config_corresponding_root Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_config_substitutions Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_consistant_parts_after_move_partition Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_consistent_parts_after_clone_replica Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_create_user_and_login Split test 'test_create_user_and_login' into two. 2020-07-10 17:16:47 +03:00
test_cross_replication Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_custom_settings Use previous users.xml if failed to reload. 2020-09-19 16:21:12 +03:00
test_ddl_alter_query Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_default_compression_codec Merge remote-tracking branch 'upstream/master' into HEAD 2020-09-16 21:07:35 +03:00
test_default_database_on_cluster Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_default_role Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_delayed_replica_failover Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_dictionaries_access Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_dictionaries_all_layouts_separate_sources Disable cassandra tests with thread sanitizer 2020-10-08 13:48:53 +03:00
test_dictionaries_complex_key_cache_string Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_dictionaries_ddl Merge pull request #14864 from bharatnc/ncb/format-integration-tests 2020-09-16 20:40:57 +03:00
test_dictionaries_dependency enable more tests 2020-09-22 17:29:09 +03:00
test_dictionaries_dependency_xml Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_dictionaries_mysql Fix race condition in MySQL pool 2020-10-08 18:50:09 +03:00
test_dictionaries_null_value Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_dictionaries_redis add support of cache layout for redis dictionaries with complex key 2020-10-14 22:57:07 +03:00
test_dictionaries_select_all Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_dictionaries_update_and_reload Remove executable bit from non-executable files 2020-10-11 19:21:29 +03:00
test_dictionary_allow_read_expired_keys Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_dictionary_custom_settings Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_dictionary_ddl_on_cluster Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_disabled_mysql_server Trigger CI 2020-10-28 22:44:37 +03:00
test_disk_access_storage Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_disk_types Fix typos reported by codespell 2020-10-27 12:04:03 +01:00
test_distributed_backward_compatability Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_distributed_ddl Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_distributed_ddl_on_cross_replication fix DDDL with cross-replication and Atomic 2020-09-23 21:28:59 +03:00
test_distributed_ddl_parallel Add test_distributed_ddl_parallel 2020-09-12 02:33:17 +03:00
test_distributed_ddl_password Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_distributed_format Set use_compact_format_in_distributed_parts_names=0 for some integration tests 2020-11-06 21:02:44 +03:00
test_distributed_inter_server_secret Fix test_distributed_inter_server_secret under ASAN 2020-10-03 11:16:31 +03:00
test_distributed_load_balancing Fix typos reported by codespell 2020-10-27 12:04:03 +01:00
test_distributed_over_distributed Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_distributed_respect_user_timeouts Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_distributed_storage_configuration Set use_compact_format_in_distributed_parts_names=0 for some integration tests 2020-11-06 21:02:44 +03:00
test_distributed_system_query Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_drop_replica Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_enabling_access_management Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_extreme_deduplication Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_fetch_partition_from_auxiliary_zookeeper Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_fetch_partition_with_outdated_parts add integration test 2020-11-01 16:02:09 +08:00
test_filesystem_layout enable more tests 2020-09-22 17:29:09 +03:00
test_force_deduplication Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_format_avro_confluent Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_format_schema_on_server Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_freeze_table Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_globs_in_filepath Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_grant_and_revoke Enable rbac tests with thread sanitizer. 2020-10-13 01:03:51 +03:00
test_graphite_merge_tree Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_host_ip_change Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_http_and_readonly Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_http_handlers_config Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_https_replication Add missed file 2020-10-09 14:20:54 +03:00
test_inherit_multiple_profiles Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_input_format_parallel_parsing_memory_tracking Increase asynchronous_metrics_update_period_s to avoid syncing MemoryTracking with RSS 2020-10-30 22:02:02 +03:00
test_insert_distributed_load_balancing Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_insert_into_distributed Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_insert_into_distributed_sync_async Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_insert_into_distributed_through_materialized_view Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_live_view_over_distributed Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_log_family_s3 Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_logs_level Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_match_process_uid_against_data_owner Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_materialize_mysql_database Revise the code according to the review 2020-11-11 19:27:37 +08:00
test_max_http_connections_for_replication Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_MemoryTracking Disable syncing MemoryTracking with RSS for test_MemoryTracking 2020-10-24 02:33:16 +03:00
test_merge_table_over_distributed Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_merge_tree_s3 allow synchronous drop/detach table for Atomic 2020-09-29 16:47:08 +03:00
test_merge_tree_s3_failover Fixed move part exception getting in test_merge_tree_s3_failover. 2020-10-16 17:30:34 +03:00
test_merge_tree_s3_with_cache fix more tests 2020-09-14 15:49:04 +03:00
test_multiple_disks More attempt to fix test_jbod_overflow. 2020-10-29 16:15:19 +03:00
test_mutations_hardlinks Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_mutations_in_partitions_of_merge_tree ALTER UPDATE/DELETE ... IN PARTITION with partition pruning in ReplicatedMergeTree (#13403) 2020-11-10 13:23:46 +03:00
test_mutations_with_merge_tree Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_mysql_database_engine Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_mysql_protocol Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_no_local_metadata_node Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_non_default_compression Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_odbc_interaction Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_old_versions Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_on_cluster_timeouts Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_part_log_table Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_partition Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_parts_delete_zookeeper Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_polymorphic_parts enable more tests 2020-09-22 17:29:09 +03:00
test_postgresql_protocol Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_profile_events_s3 Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_prometheus_endpoint Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_quorum_inserts fix tests 2020-09-22 00:09:50 +03:00
test_quorum_inserts_parallel Fix flaky tests 2020-10-09 10:19:17 +03:00
test_quota Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_random_inserts Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_range_hashed_dictionary_types Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_read_temporary_tables_on_failure Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_recompression_ttl Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_recovery_replica improvements in lost replica recovery 2020-10-07 02:29:33 +03:00
test_redirect_url_storage Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_relative_filepath Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_reload_auxiliary_zookeepers reload auxiliary zookeepers configuration 2020-11-10 15:56:37 +08:00
test_reload_max_table_size_to_drop Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_reload_zookeeper remove unused codes2 2020-11-03 19:40:45 +08:00
test_reloading_settings_from_users_xml Use previous users.xml if failed to reload. 2020-09-19 16:21:12 +03:00
test_reloading_storage_configuration Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_remote_prewhere Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_rename_column Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_replace_partition Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_replica_can_become_leader Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_replicated_merge_tree_config Update test.py 2020-09-17 11:48:27 +03:00
test_replicated_merge_tree_s3 Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_replicated_mutations Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_replicated_parse_zk_metadata Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_replicating_constants Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_replication_credentials Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_replication_without_zookeeper Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_role Enable rbac tests with thread sanitizer. 2020-10-13 01:03:51 +03:00
test_row_policy fix tests 2020-09-22 00:09:50 +03:00
test_s3_with_https Use S3 multi object delete 2020-09-28 11:47:04 +03:00
test_s3_with_proxy Merge branch 'master' of https://github.com/ClickHouse/ClickHouse into multi_delete_in_s3 2020-09-28 12:00:34 +03:00
test_send_crash_reports Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_send_request_to_leader_replica Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_server_initialization Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_settings_constraints Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_settings_constraints_distributed Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_settings_profile Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_storage_hdfs Change test to run flaky check 2020-10-06 16:29:50 +03:00
test_storage_kafka Test for the issue #12615 2020-11-06 17:54:44 +01:00
test_storage_kerberized_kafka Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_storage_mongodb Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_storage_mysql Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_storage_rabbitmq Much more optimal queues setup 2020-10-27 11:00:01 +00:00
test_storage_s3 Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_system_flush_logs add missing __init__.py 2020-10-28 13:22:10 +03:00
test_system_merges enable more tests 2020-09-22 17:29:09 +03:00
test_system_metrics Update test 2020-10-15 22:01:18 +03:00
test_system_queries add missing __init__.py 2020-10-28 13:22:10 +03:00
test_system_replicated_fetches Rename table 2020-10-27 16:07:50 +03:00
test_text_log_level Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_timezone_config Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_tmp_policy Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_ttl_move Simplify TTL move test 2020-10-21 13:11:26 +03:00
test_ttl_replicated Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_union_header Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_user_directories Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_user_ip_restrictions Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_user_zero_database_access Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
test_version_update_after_mutation Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
test_zookeeper_config Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00
.dockerignore Move all folders inside /dbms one level up (#9974) 2020-04-02 02:51:21 +03:00
.gitignore Move all folders inside /dbms one level up (#9974) 2020-04-02 02:51:21 +03:00
CMakeLists.txt Add explicit main_configs, user_configs and dictionaries in integration tests. 2020-08-12 11:55:04 +03:00
conftest.py Format and optimize imports in integration test files 2020-09-15 23:10:54 -07:00
pytest.ini improvements 2020-04-17 11:42:51 +03:00
README.md fix initial query id 2020-10-20 00:26:10 +03:00
runner Convert to python3 (#15007) 2020-10-02 19:54:07 +03:00

ClickHouse integration tests

This directory contains tests that involve several ClickHouse instances, custom configs, ZooKeeper, etc.

Running natively

Prerequisites:

  • Ubuntu 14.04 (Trusty) or higher.
  • docker. Minimum required API version: 1.25, check with docker version.

You must install latest Docker from https://docs.docker.com/engine/installation/linux/docker-ce/ubuntu/#set-up-the-repository Don't use Docker from your system repository.

  • pip and libpq-dev. To install: sudo apt-get install python3-pip libpq-dev zlib1g-dev libcrypto++-dev libssl-dev
  • py.test testing framework. To install: sudo -H pip install pytest
  • docker-compose and additional python libraries. To install:
sudo -H pip install \
    PyMySQL \
    aerospike \
    avro \
    cassandra-driver \
    confluent-kafka \
    dicttoxml \
    docker \
    docker-compose==1.22.0 \
    grpcio \
    grpcio-tools \
    kafka-python \
    kazoo \
    minio \
    protobuf \
    psycopg2-binary==2.7.5 \
    pymongo \
    pytest \
    pytest-timeout \
    redis \
    tzlocal \
    urllib3

(highly not recommended) If you really want to use OS packages on modern debian/ubuntu instead of "pip": sudo apt install -y docker docker-compose python3-pytest python3-dicttoxml python3-docker python3-pymysql python3-pymongo python3-tzlocal python3-kazoo python3-psycopg2 kafka-python python3-pytest-timeout python3-minio

If you want to run the tests under a non-privileged user, you must add this user to docker group: sudo usermod -aG docker $USER and re-login. (You must close all your sessions (for example, restart your computer)) To check, that you have access to Docker, run docker ps.

Run the tests with the pytest command. To select which tests to run, use: pytest -k <test_name_pattern>

By default tests are run with system-wide client binary, server binary and base configs. To change that, set the following environment variables:`

  • CLICKHOUSE_TESTS_SERVER_BIN_PATH to choose the server binary.
  • CLICKHOUSE_TESTS_CLIENT_BIN_PATH to choose the client binary.
  • CLICKHOUSE_TESTS_BASE_CONFIG_DIR to choose the directory from which base configs (config.xml and users.xml) are taken.

For tests that use common docker compose files you may need to set up their path with environment variable: DOCKER_COMPOSE_DIR=$HOME/ClickHouse/docker/test/integration/runner/compose

Running with runner script

The only requirement is fresh configured docker and docker pull yandex/clickhouse-integration-tests-runner

Notes:

  • If you want to run integration tests without sudo you have to add your user to docker group sudo usermod -aG docker $USER. More information about docker configuration.
  • If you already had run these tests without ./runner script you may have problems with pytest cache. It can be removed with rm -r __pycache__ .pytest_cache/.
  • Some tests maybe require a lot of resources (CPU, RAM, etc.). Better not try large tests like test_cluster_copier or test_distributed_ddl* on your laptop.

You can run tests via ./runner script and pass pytest arguments as last arg:

$ ./runner --binary $HOME/ClickHouse/programs/clickhouse  --bridge-binary $HOME/ClickHouse/programs/clickhouse-odbc-bridge --base-configs-dir $HOME/ClickHouse/programs/server/ 'test_odbc_interaction -ss'
Start tests
============================= test session starts ==============================
platform linux2 -- Python 2.7.15rc1, pytest-4.0.0, py-1.7.0, pluggy-0.8.0
rootdir: /ClickHouse/tests/integration, inifile: pytest.ini
collected 6 items

test_odbc_interaction/test.py Removing network clickhouse_default
...

Killing roottestodbcinteraction_node1_1     ... done
Killing roottestodbcinteraction_mysql1_1    ... done
Killing roottestodbcinteraction_postgres1_1 ... done
Removing roottestodbcinteraction_node1_1     ... done
Removing roottestodbcinteraction_mysql1_1    ... done
Removing roottestodbcinteraction_postgres1_1 ... done
Removing network roottestodbcinteraction_default

==================== 6 passed, 1 warnings in 95.21 seconds =====================

Path to binary and configs maybe specified via env variables:

$ export CLICKHOUSE_TESTS_BASE_CONFIG_DIR=$HOME/ClickHouse/programs/server/
$ export CLICKHOUSE_TESTS_SERVER_BIN_PATH=$HOME/ClickHouse/programs/clickhouse
$ export CLICKHOUSE_TESTS_ODBC_BRIDGE_BIN_PATH=$HOME/ClickHouse/programs/clickhouse-odbc-bridge
$ ./runner 'test_odbc_interaction'
$ # or ./runner '-v -ss'
Start tests
============================= test session starts ==============================
platform linux2 -- Python 2.7.15rc1, pytest-4.0.0, py-1.7.0, pluggy-0.8.0
rootdir: /ClickHouse/tests/integration, inifile: pytest.ini
collected 6 items

test_odbc_interaction/test.py ......                                     [100%]
==================== 6 passed, 1 warnings in 96.33 seconds =====================

You can just open shell inside a container by overwritting the command: ./runner --command=bash

Rebuilding the docker containers

The main container used for integration tests lives in docker/test/integration/Dockerfile. Rebuild it with

cd docker/test/integration
docker build -t yandex/clickhouse-integration-test .

The helper container used by the runner script is in docker/test/integration/runner/Dockerfile.

Adding new tests

To add new test named foo, create a directory test_foo with an empty __init__.py and a file named test.py containing tests in it. All functions with names starting with test will become test cases.

helpers directory contains utilities for:

  • Launching a ClickHouse cluster with or without ZooKeeper in docker containers.
  • Sending queries to launched instances.
  • Introducing network failures such as severing network link between two instances.

To assert that two TSV files must be equal, wrap them in the TSV class and use the regular assert statement. Example: assert TSV(result) == TSV(reference). In case the assertion fails, pytest will automagically detect the types of variables and only the small diff of two files is printed.