Merge pull request #8301 from aabadie/pr/flake8/testrunner

dist/tools/testrunner: fix flake8 remaining issues

.travis.yml

 dist: trusty
 
 before_install:
-  - sudo apt-get install coreutils realpath doxygen graphviz python-lesscpy cppcheck coccinelle pcregrep python3-flake8
+  - sudo apt-get install coreutils realpath doxygen graphviz python-lesscpy cppcheck coccinelle pcregrep python3-pip
+  - sudo pip3 install flake8
 
 script:
   - make static-test

dist/tools/testrunner/testrunner.py

@@ -17,7 +17,7 @@ import pexpect
 
 PEXPECT_PATH = os.path.dirname(pexpect.__file__)
 RIOTBASE = os.environ['RIOTBASE'] or \
-           os.path.abspath(os.path.join(os.path.dirname(__file__), "..", "..", ".."))
+    os.path.abspath(os.path.join(os.path.dirname(__file__), "..", "..", ".."))
 
 # Setting an empty 'TESTRUNNER_START_DELAY' environment variable use the
 # default value (3)
@@ -27,12 +27,14 @@ MAKE_TERM_STARTED_DELAY = int(os.environ.get('TESTRUNNER_START_DELAY') or 3)
 def list_until(l, cond):
     return l[:([i for i, e in enumerate(l) if cond(e)][0])]
 
+
 def find_exc_origin(exc_info):
     pos = list_until(extract_tb(exc_info),
                      lambda frame: frame[0].startswith(PEXPECT_PATH)
-                    )[-1]
+                     )[-1]
     return (pos[3], os.path.relpath(os.path.abspath(pos[0]), RIOTBASE), pos[1])
 
+
 def run(testfunc, timeout=10, echo=True, traceback=False):
     env = os.environ.copy()
     child = pexpect.spawnu("make term", env=env, timeout=timeout)