Fix grasshopper in rhino 8 failing to call python properly (#206)

Author: jamesramsden-bh

Python_Engine/Compute/Download.cs

@@ -91,7 +91,7 @@ public static string DownloadFile(
 
         [Description("Download and install a specified version of python, and return the executable for it.")]
         [Input("version", "The version of python to download.")]
-        [Output("pythonExecutable", "The executable (python.exe) for the python version that was installed")]
+        [Output("pythonExecutable", "The executable (python.exe) for the python version that was installed.")]
         public static string DownloadPythonVersion(this PythonVersion version)
         {
             string url = version.EmbeddableURL();
@@ -122,6 +122,7 @@ public static string DownloadPythonVersion(this PythonVersion version)
                 }
             })
             {
+                install.StartInfo.Environment["PYTHONHOME"] = "";
                 install.Start();
                 string stderr = install.StandardError.ReadToEnd();
                 install.WaitForExit();

Python_Engine/Compute/InstallPackage.cs Python_Engine/Compute/Install.csPython_Engine/Compute/InstallPackage.cs renamed to Python_Engine/Compute/Install.cs

@@ -59,9 +59,10 @@ List<string> packages
                     FileName = executable,
                     Arguments = $"-m pip install --no-warn-script-location {packagesString}",
                     UseShellExecute = false,
-                    RedirectStandardError = true,
+                    RedirectStandardError = true
                 }
             };
+            process.StartInfo.Environment["PYTHONHOME"] = "";
             using (Process p = Process.Start(process.StartInfo))
             {
                 string standardError = p.StandardError.ReadToEnd();
@@ -111,6 +112,7 @@ string requirements
                     RedirectStandardError = true,
                 }
             };
+            process.StartInfo.Environment["PYTHONHOME"] = "";
             using (Process p = Process.Start(process.StartInfo))
             {
                 string standardError = p.StandardError.ReadToEnd();
@@ -155,6 +157,7 @@ string packageDirectory
                     RedirectStandardError = true,
                 }
             };
+            process.StartInfo.Environment["PYTHONHOME"] = "";
             using (Process p = Process.Start(process.StartInfo))
             {
                 string standardError = p.StandardError.ReadToEnd();

Python_Engine/Compute/Remove.cs

@@ -109,6 +109,7 @@ public static void RemoveBaseVersion(PythonVersion version = PythonVersion.v3_10
                 }
             })
             {
+                uninstall.StartInfo.Environment["PYTHONHOME"] = "";
                 uninstall.Start();
                 string stderr = uninstall.StandardError.ReadToEnd();
                 uninstall.WaitForExit();

Python_Engine/Compute/RequirementsTxt.cs

@@ -69,6 +69,8 @@ public static string RequirementsTxt(
                     RedirectStandardOutput = true
                 }
             };
+
+            process.StartInfo.Environment["PYTHONHOME"] = "";
             using (Process p = Process.Start(process.StartInfo))
             {
                 StreamWriter sr = new StreamWriter(targetPath);

Python_Engine/Compute/Run.cs

@@ -52,6 +52,7 @@ public static string RunCommandStdout(string command, bool hideWindows = true, s
                 process.StartInfo.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
                 commandMode = "/C";
             }
+            process.StartInfo.Environment["PYTHONHOME"] = "";
             process.StartInfo.FileName = "cmd.exe";
             process.StartInfo.RedirectStandardOutput = true;
             process.StartInfo.RedirectStandardError = true;

Python_Engine/Compute/VirtualEnvironment.cs

@@ -91,6 +91,8 @@ public static PythonEnvironment VirtualEnvironment(this PythonVersion version, s
                 }
             };
 
+            process.StartInfo.Environment["PYTHONHOME"] = "";
+
             using (Process p = Process.Start(process.StartInfo))
             {
                 string standardError = p.StandardError.ReadToEnd();
@@ -114,6 +116,8 @@ public static PythonEnvironment VirtualEnvironment(this PythonVersion version, s
                 }
             };
 
+            process.StartInfo.Environment["PYTHONHOME"] = "";
+
             using (Process p = Process.Start(process2.StartInfo))
             {
                 string standardError = p.StandardError.ReadToEnd();