Fixed an issue when configuration file options partly ignored when `--project-conf` // Resolve #3034 (#3055)

* Fixed an issue when configuration file options partly ignored when using custom ``--project-conf`` // Resolve #3034

* Py2 compatible makedirs

* Fix circle dependency

* Fix broken import in test examples

* Fix history

* Remove YAPF markers

* PyLint fix

* Fix invalid project conf path

* Move PIO Core to the root on Windows, issue with long CPPPATHs

* Respect global PLATFORMIO_BUILD_CACHE_DIR env var

* Fix Appveyor paths

* Minor changes

platformio/test/processor.py

@@ -20,7 +20,6 @@ from string import Template
 import click
 
 from platformio import exception
-from platformio.project.helpers import get_project_test_dir
 
 TRANSPORT_OPTIONS = {
     "arduino": {
@@ -104,7 +103,9 @@ class TestProcessorBase(object):
 
     def build_or_upload(self, target):
         if not self._outputcpp_generated:
-            self.generate_outputcpp(get_project_test_dir())
+            self.generate_outputcpp(
+                self.options["project_config"].get_optional_dir("test")
+            )
             self._outputcpp_generated = True
 
         if self.test_name != "*":
@@ -175,7 +176,7 @@ class TestProcessorBase(object):
                 "   $end;",
                 "}",
             ]
-        )  # yapf: disable
+        )
 
         def delete_tmptest_file(file_):
             try: