Parallel test runner

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog
 
+### 44.0.1 [#1349](https://github.com/openfisca/openfisca-core/pull/1349)
+
+#### Technical changes
+
+- Add parallel execution of tests to `openfisca test` command line.
+
 # 44.0.0 [#1346](https://github.com/openfisca/openfisca-core/pull/1346)
 
 #### Technical changes

README.md

@@ -87,6 +87,15 @@ To run the entire test suite:
 make test
 ```
 
+If you have many tests, you could run them in parallel :
+```sh
+make test-core openfisca_args="--in-parallel"
+```
+
+You could add an option  `--num-workers=4` to limit to 4 threads. Default is your CPU Core number minus 1.
+
+Be aware that this add overhead so use it only for huge test suite.
+
 To run all the tests defined on a test file:
 
 ```sh

openfisca_core/scripts/openfisca_command.py

@@ -1,6 +1,7 @@
 import argparse
 import sys
 import warnings
+from importlib.metadata import version
 
 from openfisca_core.scripts import add_tax_benefit_system_arguments
 
@@ -11,6 +12,11 @@
 
 def get_parser():
     parser = argparse.ArgumentParser()
+    parser.add_argument(
+        "--version",
+        action="version",
+        version=f"OpenFisca-Core {version('OpenFisca-Core')}",
+    )
 
     subparsers = parser.add_subparsers(help="Available commands", dest="command")
     subparsers.required = (
@@ -134,6 +140,18 @@ def build_test_parser(parser):
             default=None,
             help="variables to ignore. If specified, do not test the given variables.",
         )
+        parser.add_argument(
+            "--in-parallel",
+            action="store_true",
+            default=False,
+            help="run tests in parallel",
+        )
+        parser.add_argument(
+            "--num-workers",
+            type=int,
+            default=0,
+            help="number of parallel workers (default: CPU count - 1)",
+        )
 
         return parser
 

openfisca_core/scripts/run_test.py

@@ -20,6 +20,9 @@ def main(parser) -> None:
     )
 
     options = {
+        "country_package": args.country_package,
+        "extensions": args.extensions,
+        "reforms": args.reforms,
         "pdb": args.pdb,
         "performance_graph": args.performance_graph,
         "performance_tables": args.performance_tables,
@@ -32,4 +35,16 @@ def main(parser) -> None:
     }
 
     paths = [os.path.abspath(path) for path in args.path]
+
+    # Parallel mode
+    if args.in_parallel:
+        from openfisca_core.tools.test_runner import run_tests_in_parallel
+
+        return sys.exit(
+            run_tests_in_parallel(
+                tax_benefit_system, paths, options, args.num_workers, args.verbose
+            )
+        )
+
+    # Default serial mode
     sys.exit(run_tests(tax_benefit_system, paths, options))

openfisca_core/tools/parallel_plugin.py

@@ -0,0 +1,55 @@
+"""Pytest plugin for running OpenFisca tests in parallel worker processes.
+
+This plugin is loaded by pytest workers spawned by run_tests_in_parallel().
+It configures each worker with its own tax-benefit system and test options.
+
+The parallel test architecture works as follows:
+1. Main process: run_tests_in_parallel() splits test files into batches
+2. Main process: spawns multiple pytest workers via subprocess
+3. Each worker: loads this plugin to configure its test environment
+4. Each worker: runs its batch of tests independently
+5. Main process: aggregates results and reports failures
+
+Configuration is passed via environment variables:
+- OPENFISCA_COUNTRY_PACKAGE: The country package to load
+- OPENFISCA_EXTENSIONS: JSON array of extensions to load
+- OPENFISCA_REFORMS: JSON array of reforms to apply
+- OPENFISCA_OPTIONS: JSON object with test options (verbose, name_filter, etc.)
+"""
+
+import json
+import os
+
+from openfisca_core.scripts import build_tax_benefit_system
+from openfisca_core.tools.test_runner import OpenFiscaPlugin
+
+
+def pytest_configure(config):
+    """Pytest hook called when each worker process initializes.
+
+    This function is automatically invoked by pytest when it loads this plugin.
+    It sets up the OpenFisca test environment for the worker by:
+    1. Reading configuration from environment variables
+    2. Building the tax-benefit system with specified country, extensions, and reforms
+    3. Registering the OpenFisca plugin with pytest
+
+    Args:
+        config: Pytest config object provided by pytest framework
+    """
+    # Extract country package from environment (optional)
+    country = os.environ.get("OPENFISCA_COUNTRY_PACKAGE") or None
+
+    # Parse JSON arrays for extensions and reforms
+    extensions = json.loads(os.environ.get("OPENFISCA_EXTENSIONS", "[]"))
+    reforms = json.loads(os.environ.get("OPENFISCA_REFORMS", "[]"))
+
+    # Build the tax-benefit system with the specified configuration
+    tbs = build_tax_benefit_system(country, extensions, reforms)
+
+    # Parse test options (verbose, name_filter, etc.)
+    options_json = os.environ.get("OPENFISCA_OPTIONS", "{}")
+    options = json.loads(options_json)
+
+    # Create and register the OpenFisca plugin for this worker
+    plugin = OpenFiscaPlugin(tbs, options)
+    config.pluginmanager.register(plugin, name="openfisca_parallel_plugin")