Establishing dependencies on specific test parameterizations#

Tests can depend on specific paramterizations of other tests.

Example#

The test lunch depends on breakfast, but only when dish="spam":

# Copyright NTESS. See COPYRIGHT file for details.
#
# SPDX-License-Identifier: MIT

import canary

canary.directives.parameterize("dish", ("eggs", "ham", "spam"))

# Copyright NTESS. See COPYRIGHT file for details.
#
# SPDX-License-Identifier: MIT

import sys

import canary

canary.directives.depends_on("breakfast.dish=spam")


def lunch() -> int:
    instance = canary.get_instance()
    assert instance.dependencies[0].family == "breakfast"
    assert instance.dependencies[0].parameters.dish == "spam"


if __name__ == "__main__":
    sys.exit(lunch())

$ canary run ./depends_on/parameter
INFO: Initializing empty canary workspace at .
INFO: Collecting generator files from depends_on/parameter
INFO: Instantiating generators from collected files
INFO: Generating test specs from generators
INFO: Searching for duplicated tests
INFO: Resolving test spec dependencies
INFO: Generated 4 test specs from 2 generators
INFO: Caching test specs
INFO: Created selection 'silver-acorn'
INFO: Selecting test cases based on runtime environment
INFO: Starting session 2026-04-21T15-34-28.346793
INFO: Starting process pool with max 2 workers
Job                  ID        Status                                           Queued   Elapsed      Rank  
──────────────────────────────────────────────────────────────────────────────────────────────────────────
breakfast.dish=spam  7ade8ab   SUBMITTED                                                               2/4  
breakfast.dish=spam  7ade8ab   STARTED                                            0.3s                 2/4  
breakfast.dish=eggs  402d80b   SUBMITTED                                                               1/4  
breakfast.dish=eggs  402d80b   STARTED                                            0.3s                 1/4  
breakfast.dish=spam  7ade8ab   PASS (SUCCESS)                                     0.3s      0.5s       2/4  
breakfast.dish=eggs  402d80b   PASS (SUCCESS)                                     0.3s      0.5s       1/4  
lunch                78fa499   SUBMITTED                                                               4/4  
lunch                78fa499   STARTED                                            0.0s                 4/4  
breakfast.dish=ham   edbd66f   SUBMITTED                                                               3/4  
breakfast.dish=ham   edbd66f   STARTED                                            0.0s                 3/4  
lunch                78fa499   PASS (SUCCESS)                                     0.0s      0.2s       4/4  
breakfast.dish=ham   edbd66f   PASS (SUCCESS)                                     0.0s      0.2s       3/4  
INFO: 4/4 tests finished with status PASS
INFO: Finished session in 0.79 s. with returncode 0
INFO: Updating view at /home/docs/checkouts/readthedocs.org/user_builds/canary-wm/checkouts/release-26.4.16/src/canary/examples/TestResults
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