add pikepdf to test dependencies

.travis.yml

@@ -24,7 +24,7 @@ matrix:
         - python3 -m pip install --upgrade virtualenv
         - virtualenv -p python3 --system-site-packages "$HOME/venv"
         - source "$HOME/venv/bin/activate"
-install: pip install wheel pillow pytest pdfrw
+install: pip install wheel pillow pytest pdfrw pikepdf
 script:
   - python --version
   - python setup.py test

appveyor.yml

@@ -16,7 +16,7 @@ environment:
     - PYTHON: "C:\\Python37-x64"
 
 install:
-  - "%PYTHON%\\python.exe -m pip install wheel pytest pdfrw pillow pyinstaller"
+  - "%PYTHON%\\python.exe -m pip install wheel pytest pdfrw pillow pyinstaller pikepdf"
 
 build: off
 

setup.py

@@ -9,6 +9,7 @@ INSTALL_REQUIRES = (
 
 TESTS_REQUIRE = (
     'pdfrw',
+    'pikepdf',
 )