fix minor issues in test runner scripts on device (esp8266#4542)

* tests/device/Makefile: use bourne shell compatible "." instead ot "source" (ubuntu's dash does not understand it)

* tests/device: make BEGINTIMEOUT a new error return value instead of a test-process-breaking exception

Author: d-a-v

tests/device/libraries/BSTest/Makefile

@@ -11,10 +11,10 @@ clean:
 
 $(PYTHON_ENV_DIR):
 	virtualenv --no-site-packages $(PYTHON_ENV_DIR)
-	source $(PYTHON_ENV_DIR)/bin/activate && pip install -r requirements.txt
+	. $(PYTHON_ENV_DIR)/bin/activate && pip install -r requirements.txt
 
 test: $(TEST_EXECUTABLE) $(PYTHON_ENV_DIR)
-	source $(PYTHON_ENV_DIR)/bin/activate && python runner.py -e $(TEST_EXECUTABLE)
+	. $(PYTHON_ENV_DIR)/bin/activate && python runner.py -e $(TEST_EXECUTABLE)
 
 $(TEST_EXECUTABLE): test/test.cpp
 	g++ -std=c++11 -Isrc -o $@ test/test.cpp

tests/device/libraries/BSTest/runner.py

@@ -32,6 +32,7 @@ class BSTestRunner(object):
     FAIL = 1
     TIMEOUT = 2
     CRASH = 3
+    BEGINTIMEOUT = 4
 
     def __init__(self, spawn_obj, name, mocks):
         self.sp = spawn_obj
@@ -116,7 +117,7 @@ def run_test(self, index):
             time.sleep(0.1)
             timeout -= 0.1
         if timeout <= 0:
-            raise 'test begin timeout'
+            return BSTestRunner.BEGINTIMEOUT
         while timeout > 0:
             res = self.sp.expect([r'>>>>>bs_test_check_failure line=(\d+)',
                             r'>>>>>bs_test_end line=(\d+) result=(\d+) checks=(\d+) failed_checks=(\d+)',