Fixed an issue when a custom "pio test --project-config" was not handled properly // Resolve #4299

HISTORY.rst

@@ -13,6 +13,11 @@ PlatformIO Core 6
 
 **A professional collaborative platform for declarative, safety-critical, and test-driven embedded development.**
 
+6.0.3 (2022-??-??)
+~~~~~~~~~~~~~~~~~~
+
+- Fixed an issue when a custom `pio test --project-config <https://docs.platformio.org/en/latest/core/userguide/cmd_test.html#cmdoption-pio-test-c>`__ was not handled properly (`issue #4299 <https://github.com/platformio/platformio-core/issues/4299>`_)
+
 6.0.2 (2022-06-01)
 ~~~~~~~~~~~~~~~~~~
 

platformio/builder/main.py

@@ -28,7 +28,7 @@ from SCons.Script import DefaultEnvironment  # pylint: disable=import-error
 from SCons.Script import Import  # pylint: disable=import-error
 from SCons.Script import Variables  # pylint: disable=import-error
 
-from platformio import compat, fs
+from platformio import app, compat, fs
 from platformio.platform.base import PlatformBase
 from platformio.proc import get_pythonexe_path
 from platformio.project.helpers import get_project_dir
@@ -110,6 +110,8 @@ env.Replace(
 
 # Setup project optional directories
 config = env.GetProjectConfig()
+app.set_session_var("custom_project_conf", config.path)
+
 env.Replace(
     PROJECT_DIR=get_project_dir(),
     PROJECT_CORE_DIR=config.get("platformio", "core_dir"),