Add Conda support again

Author: mrkn

.github/workflows/windows.yml

@@ -101,14 +101,25 @@ jobs:
 
     - run: python -c 'import numpy; print(numpy)'
 
+    - run: python -c 'import os; print(os.environ)'
+
     - run: bundle install
 
     - run: rake compile
 
     - run: python lib/pycall/python/investigator.py
 
     - run: |
-        rake
+        ruby -Ilib -Iext/pycall -rpycall -e "p PyCall.sys.version"
+        ruby -Ilib -Iext/pycall -rpycall -e "PyCall.import_module(:numpy)"
       env:
         PYTHON: python
+      continue-on-error: true
 
+    - run: |
+        echo $env:PATH
+        rake
+      env:
+        PYTHON: python
+        CONDA_DLL_SEARCH_MODIFICATION_ENABLE: 1
+      continue-on-error: true

lib/pycall/libpython/finder.rb

@@ -42,6 +42,14 @@ def find_libpython(python = nil)
           python, python_config = find_python_config(python)
           suffix = python_config[:SHLIB_SUFFIX]
 
+          use_conda = (ENV.fetch("CONDA_PREFIX", nil) == File.dirname(python_config[:executable]))
+          python_home = if !ENV.key?("PYTHONHOME") || use_conda
+                          python_config[:PYTHONHOME]
+                        else
+                          ENV["PYTHONHOME"]
+                        end
+          ENV["PYTHONHOME"] = python_home
+
           candidate_paths(python_config) do |path|
             debug_report("Candidate: #{path}")
             normalized = normalize_path(path, suffix)

lib/pycall/python/investigator.py

@@ -72,4 +72,14 @@ def _linked_libpython_windows():
           get_config_var("VERSION")
 print("VERSION: {val}".format(val=version))
 
-print("version_major: {val}".format(val=sys.version_info.major))
+if is_windows:
+    if hasattr(sys, "base_exec_prefix"):
+        PYTHONHOME = sys.base_exec_prefix
+    else:
+        PYTHONHOME = sys.exec_prefix
+else:
+    if hasattr(sys, "base_exec_prefix"):
+        PYTHONHOME = ":".join([sys.base_prefix, sys.base_exec_prefix])
+    else:
+        PYTHONHOME = ":".join([sys.prefix, sys.exec_prefix])
+print("PYTHONHOME: {val}".format(val=PYTHONHOME))