Travis throws Python syntax error from a print statement in node-sass when using pytest

Question

I'm having a strange problem with Travis when testing a Django app with pytest-django. All my tests pass locally and apparently on travis as well but no matter what I do, I get errors from node-sass and node-gyp each time.

None of my test use any node modules (if that is even possible). I do use gulp that has gulp-sass but that seems to work fine when it's ran before the tests run.

Here is the error output:

$ py.test --ds=<project>.settings.travis
============================= test session starts ==============================
platform linux -- Python 3.4.2 -- py-1.4.26 -- pytest-2.6.4
django settings: <project>.settings.travis (from command line option)
plugins: django
collected 13 items / 7 errors 
<project>/tests/test_<suite_1>.py ..........
<project>/tests/test_<suite_2>.py ...
==================================== ERRORS ====================================
 ERROR collecting node_modules/gulp-sass/node_modules/node-sass/node_modules/node-gyp/gyp/pylib/gyp/MSVSSettings_test.py 
../../../virtualenv/python3.4.2/lib/python3.4/site-packages/_pytest/python.py:463: in _importtestmodule
    mod = self.fspath.pyimport(ensuresyspath=True)
../../../virtualenv/python3.4.2/lib/python3.4/site-packages/py/_path/local.py:629: in pyimport
    __import__(pkgpath.basename)
E     File "/home/travis/build/<user>/<project>/node_modules/gulp-sass/node_modules/node-sass/node_modules/node-gyp/gyp/pylib/gyp/__init__.py", line 37
E       print '%s:%s:%d:%s %s' % (mode.upper(), os.path.basename(ctx[0]),
E                            ^
E   SyntaxError: invalid syntax
 ERROR collecting node_modules/gulp-sass/node_modules/node-sass/node_modules/node-gyp/gyp/pylib/gyp/common_test.py 
../../../virtualenv/python3.4.2/lib/python3.4/site-packages/_pytest/python.py:463: in _importtestmodule
    mod = self.fspath.pyimport(ensuresyspath=True)
../../../virtualenv/python3.4.2/lib/python3.4/site-packages/py/_path/local.py:629: in pyimport
    __import__(pkgpath.basename)
E     File "/home/travis/build/<user>/<project>/node_modules/gulp-sass/node_modules/node-sass/node_modules/node-gyp/gyp/pylib/gyp/__init__.py", line 37
E       print '%s:%s:%d:%s %s' % (mode.upper(), os.path.basename(ctx[0]),
E                            ^
E   SyntaxError: invalid syntax
 ERROR collecting node_modules/gulp-sass/node_modules/node-sass/node_modules/node-gyp/gyp/pylib/gyp/easy_xml_test.py 
../../../virtualenv/python3.4.2/lib/python3.4/site-packages/_pytest/python.py:463: in _importtestmodule
    mod = self.fspath.pyimport(ensuresyspath=True)
../../../virtualenv/python3.4.2/lib/python3.4/site-packages/py/_path/local.py:629: in pyimport
    __import__(pkgpath.basename)
E     File "/home/travis/build/<user>/<project>/node_modules/gulp-sass/node_modules/node-sass/node_modules/node-gyp/gyp/pylib/gyp/__init__.py", line 37
E       print '%s:%s:%d:%s %s' % (mode.upper(), os.path.basename(ctx[0]),
E                            ^
E   SyntaxError: invalid syntax
 ERROR collecting node_modules/gulp-sass/node_modules/node-sass/node_modules/node-gyp/gyp/pylib/gyp/input_test.py 
../../../virtualenv/python3.4.2/lib/python3.4/site-packages/_pytest/python.py:463: in _importtestmodule
    mod = self.fspath.pyimport(ensuresyspath=True)
../../../virtualenv/python3.4.2/lib/python3.4/site-packages/py/_path/local.py:629: in pyimport
    __import__(pkgpath.basename)
E     File "/home/travis/build/<user>/<project>/node_modules/gulp-sass/node_modules/node-sass/node_modules/node-gyp/gyp/pylib/gyp/__init__.py", line 37
E       print '%s:%s:%d:%s %s' % (mode.upper(), os.path.basename(ctx[0]),
E                            ^
E   SyntaxError: invalid syntax
 ERROR collecting node_modules/gulp-sass/node_modules/node-sass/node_modules/node-gyp/gyp/pylib/gyp/generator/msvs_test.py 
../../../virtualenv/python3.4.2/lib/python3.4/site-packages/_pytest/python.py:463: in _importtestmodule
    mod = self.fspath.pyimport(ensuresyspath=True)
../../../virtualenv/python3.4.2/lib/python3.4/site-packages/py/_path/local.py:629: in pyimport
    __import__(pkgpath.basename)
E     File "/home/travis/build/<user>/<project>/node_modules/gulp-sass/node_modules/node-sass/node_modules/node-gyp/gyp/pylib/gyp/__init__.py", line 37
E       print '%s:%s:%d:%s %s' % (mode.upper(), os.path.basename(ctx[0]),
E                            ^
E   SyntaxError: invalid syntax
 ERROR collecting node_modules/gulp-sass/node_modules/node-sass/node_modules/node-gyp/gyp/pylib/gyp/generator/ninja_test.py 
../../../virtualenv/python3.4.2/lib/python3.4/site-packages/_pytest/python.py:463: in _importtestmodule
    mod = self.fspath.pyimport(ensuresyspath=True)
../../../virtualenv/python3.4.2/lib/python3.4/site-packages/py/_path/local.py:629: in pyimport
    __import__(pkgpath.basename)
E     File "/home/travis/build/<user>/<project>/node_modules/gulp-sass/node_modules/node-sass/node_modules/node-gyp/gyp/pylib/gyp/__init__.py", line 37
E       print '%s:%s:%d:%s %s' % (mode.upper(), os.path.basename(ctx[0]),
E                            ^
E   SyntaxError: invalid syntax
 ERROR collecting node_modules/gulp-sass/node_modules/node-sass/node_modules/node-gyp/gyp/pylib/gyp/generator/xcode_test.py 
../../../virtualenv/python3.4.2/lib/python3.4/site-packages/_pytest/python.py:463: in _importtestmodule
    mod = self.fspath.pyimport(ensuresyspath=True)
../../../virtualenv/python3.4.2/lib/python3.4/site-packages/py/_path/local.py:629: in pyimport
    __import__(pkgpath.basename)
E     File "/home/travis/build/<user>/<project>/node_modules/gulp-sass/node_modules/node-sass/node_modules/node-gyp/gyp/pylib/gyp/__init__.py", line 37
E       print '%s:%s:%d:%s %s' % (mode.upper(), os.path.basename(ctx[0]),
E                            ^
E   SyntaxError: invalid syntax
===================== 13 passed, 7 error in 20.94 seconds ======================

Answer 1

The problem turned out to be the (old) version of pytest already installed in Travis satisfying the dependency in pytest-django. Adding the correct version of pytest to requirements.txt fixed the issue.