bpo-38809: Windows build scripts use python.exe from virtual envs (GH-17164)

https://bugs.python.org/issue38809

diff --git a/Misc/NEWS.d/next/Build/2019-11-15-09-25-44.bpo-38809.9jwta6.rst b/Misc/NEWS.d/next/Build/2019-11-15-09-25-44.bpo-38809.9jwta6.rst
new file mode 100644 (file)
index 0000000..10eaf84
--- /dev/null
+++ b/Misc/NEWS.d/next/Build/2019-11-15-09-25-44.bpo-38809.9jwta6.rst
@@ -0,0 +1,2 @@
+On Windows, build scripts will now recognize and use python.exe from an
+active virtual env.

diff --git a/PCbuild/find_python.bat b/PCbuild/find_python.bat
index d5c787fd77aa4249f27a6e664268078f933ebb8c..40937a67c33ac7a2e0ef08811018cddf6cd53c78 100644 (file)
--- a/PCbuild/find_python.bat
+++ b/PCbuild/find_python.bat
@@ -24,6 +24,9 @@
 :begin_search
 @set PYTHON=
 
+@rem If there is an active virtual env, use that one
+@if NOT "%VIRTUAL_ENV%"=="" (set PYTHON="%VIRTUAL_ENV%\Scripts\python.exe") & (set _Py_Python_Source=found in virtual env) & goto :found
+
 @set _Py_EXTERNALS_DIR=%EXTERNALS_DIR%
 @if "%_Py_EXTERNALS_DIR%"=="" (set _Py_EXTERNALS_DIR=%~dp0\..\externals)