scripts/: minor improvements to venv and use on OpenBSD

Fixes to work on OpenBSD with system libclang. And always upgrade pip when
creating venv.

scripts/gh_release.py

@@ -403,15 +403,20 @@ def venv( command=None, packages=None):
     ssp = ''
     if platform.system() == 'OpenBSD':
         # libclang not available from pypi.org, but system py3-llvm package
-        # works.
+        # works. `pip install` should be run with --no-build-isolation and
+        # explicit `pip install swig setuptools psutil`.
         ssp = ' --system-site-packages'
+        log(f'OpenBSD: libclang not available from pypi.org.')
+        log(f'OpenBSD: system package `py3-llvm` must be installed.')
+        log(f'OpenBSD: creating venv with --system-site-packages.')
+        log(f'OpenBSD: `pip install .../PyMuPDF` must be preceded by install of swig etc.')
     command2 += f'{sys.executable} -m venv{ssp} {venv_name}'
     if platform.system() == 'Windows':
         command2 += f' && {venv_name}\\Scripts\\activate'
     else:
         command2 += f' && . {venv_name}/bin/activate'
+    command2 += ' && python -m pip install --upgrade pip'
     if packages:
-        command2 += ' && python -m pip install --upgrade pip'
         if isinstance(packages, str):
             packages = packages.split(',')
         command2 += ' && pip install ' + ' '.join(packages)

scripts/test.py

@@ -40,6 +40,7 @@
 import gh_release
 
 import os
+import platform
 import sys
 
 
@@ -82,12 +83,26 @@ def main(argv):
 
 
 def build():
-    gh_release.run(f'pip install -vv {pymupdf_dir}')
+    nbi = ''
+    if platform.system() == 'OpenBSD':
+        # libclang not available on pypi.org, so we need to force use of system
+        # package py3-llvm with --no-build-isolation, manually installing other
+        # required packages.
+        gh_release.run(f'pip install swig setuptools psutil')
+        gh_release.run(f'pip install --no-build-isolation -vv {pymupdf_dir}')
+    else:
+        gh_release.run(f'pip install{nbi} -vv {pymupdf_dir}')
 
 
 def test():
     gh_release.run(f'pip install pytest fontTools psutil')
-    gh_release.run(f'{sys.executable} {pymupdf_dir}/tests/run_compound.py pytest -s {pymupdf_dir}')
+    if platform.system() == 'OpenBSD':
+        # On OpenBSD `pip install pytest` doesn't seem to install the pytest
+        # command, so we use `python -m pytest ...`. (This doesn't work on
+        # Windows for some reason so we don't use it all the time.)
+        gh_release.run(f'{sys.executable} {pymupdf_dir}/tests/run_compound.py python -m pytest -s {pymupdf_dir}')
+    else:
+        gh_release.run(f'{sys.executable} {pymupdf_dir}/tests/run_compound.py pytest -s {pymupdf_dir}')
 
 
 if __name__ == '__main__':