Use JSON to encode env vars

Author: joerick

cibuildwheel/platforms/windows.py

@@ -1,8 +1,8 @@
+import json
 import os
 import platform as platform_module
 import shutil
 import subprocess
-import sys
 import textwrap
 from collections.abc import MutableMapping, Set
 from dataclasses import dataclass
@@ -351,25 +351,22 @@ def setup_python(
             text=True,
         ).strip()
         log.notice(f"Discovering Visual Studio for GraalPy at {vcpath}")
-        vcvars = (
-            subprocess.check_output(
-                [
-                    f"{vcpath}\\Common7\\Tools\\vsdevcmd.bat",
-                    "-no_logo",
-                    "-arch=amd64",
-                    "-host_arch=amd64",
-                    "&&",
-                    "set",
-                ],
-                shell=True,
-                text=True,
-                env=env,
-            )
-            .strip()
-            .split("\n")
+        vcvars = subprocess.check_output(
+            [
+                f"{vcpath}\\Common7\\Tools\\vsdevcmd.bat",
+                "-no_logo",
+                "-arch=amd64",
+                "-host_arch=amd64",
+                "&&",
+                "python",
+                "-c",
+                "import os, json, sys; json.dump(dict(os.environ), sys.stdout);",
+            ],
+            shell=True,
+            text=True,
+            env=env,
         )
-        print("vcvars", vcvars, file=sys.stderr)
-        env.update(dict([envvar.strip().split("=", 1) for envvar in vcvars]))
+        env.update(json.loads(vcvars))
 
     return base_python, env