Travis: hack in qpdf appimage version

qpdf from appimage does not report its version with --version if renamed
or accessed via symlink. Use an environment variable to supply it
where needed.

.travis.yml

@@ -68,6 +68,7 @@ before_install: |
     sudo dpkg -i packages/unpaper_6.1-1.deb
     wget -q 'https://github.com/qpdf/qpdf/releases/download/release-qpdf-8.0.2/qpdf-8.0.2-x86_64.AppImage' -O bin/qpdf
     chmod +x bin/qpdf
+    export OCRMYPDF_QPDF_APPIMAGE=8.0.2
   elif [[ "$TRAVIS_OS_NAME" == "osx" ]]; then
     brew update && brew bundle --file=.travis/Brewfile
     pip3 install --upgrade pip
@@ -76,13 +77,11 @@ before_install: |
 
 install:
 - export PATH=$PWD/bin:$PATH
-- qpdf --version
 - pip3 install ".$EXTRAS"
 - pip3 install -r test_requirements.txt
 
 script:
 - tesseract --version
-- qpdf --version
 - pytest -n auto
 
 deploy:

setup.py

@@ -28,6 +28,7 @@ from setuptools import setup, find_packages  # nopep8
 from subprocess import STDOUT, check_output, CalledProcessError  # nopep8
 from collections.abc import Mapping  # nopep8
 import re  # nopep8
+import os  # nopep8
 
 
 missing_program = '''
@@ -184,12 +185,13 @@ if not forced and command.startswith('install') or \
         package='unpaper',
         optional=True
     )
-    check_external_program(
-        program='qpdf',
-        need_version='7.0.0', # test suite known to fail on 5.1.1
-        package='qpdf',
-        version_check_args=['--version']
-    )
+    if not os.environ.get('OCRMYPDF_QPDF_APPIMAGE'):
+        check_external_program(
+            program='qpdf',
+            need_version='7.0.0', # test suite known to fail on 5.1.1
+            package='qpdf',
+            version_check_args=['--version']
+        )
 
 if 'upload' in sys.argv[1:]:
     print('Use twine to upload the package - setup.py upload is insecure')

src/ocrmypdf/exec/qpdf.py

@@ -30,7 +30,9 @@ from ..helpers import re_symlink
 
 @lru_cache(maxsize=1)
 def version():
-    return get_version('qpdf', regex=r'qpdf version (.+)')    
+    if 'OCRMYPDF_QPDF_APPIMAGE' in os.environ:
+        return os.environ['OCRMYPDF_QPDF_APPIMAGE']
+    return get_version('qpdf', regex=r'qpdf version (.+)')
 
 
 def check(input_file, log=None):