Convert all ghostscript spoofs to test plugins

tests/plugins/gs_pdfa_failure.py

@@ -0,0 +1,51 @@
+# © 2020 James R. Barlow: github.com/jbarlow83
+#
+# Permission is hereby granted, free of charge, to any person obtaining a
+# copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be included
+# in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+# IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+# CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+# TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+from unittest.mock import patch
+
+from ocrmypdf import hookimpl
+from ocrmypdf.builtin_plugins import ghostscript
+from ocrmypdf.exec import run
+
+
+def run_rig_args(args, **kwargs):
+    # Remove the two arguments that tell ghostscript to create a PDF/A
+    # Does not remove the Postscript definition file - not necessary
+    # to cause PDF/A creation failure
+    new_args = [
+        arg for arg in args if not arg.startswith('-dPDFA') and not arg.endswith('.ps')
+    ]
+    proc = run(new_args, **kwargs)
+    return proc
+
+
+@hookimpl
+def generate_pdfa(pdf_pages, pdfmark, output_file, compression, pdf_version, pdfa_part):
+    with patch('ocrmypdf.exec.ghostscript.run', new=run_rig_args):
+        ghostscript.generate_pdfa(
+            pdf_pages=pdf_pages,
+            pdfmark=pdfmark,
+            output_file=output_file,
+            compression=compression,
+            pdf_version=pdf_version,
+            pdfa_part=pdfa_part,
+        )
+        return output_file