Revert "vpython: use realpath when invoking virtualenv"

This reverts commit 988aaae.

Reason for revert: Change is breaking luci-go to infra autoroller. https://ci.chromium.org/ui/p/infra/builders/try/infra-try-jammy-64/b8750527694180069633/overview

Original change's description:
> vpython: use realpath when invoking virtualenv
>
> Use realpath for virtualenv.pyz to mitigate pypa/virtualenv#1949
>
> Change-Id: I4ddfb78bc435f9791ccae5e87cf5c0da404a110a
> Reviewed-on: https://chromium-review.googlesource.com/c/infra/luci/luci-go/+/5449147
> Reviewed-by: Brian Ryner <bryner@google.com>
> Commit-Queue: Chenlin Fan <fancl@chromium.org>
> Auto-Submit: Chenlin Fan <fancl@chromium.org>

Change-Id: I37d27f0fd80d93f722ed000985fa5b95f51c8c6d
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/infra/luci/luci-go/+/5458911
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Auto-Submit: Randy Maldonado <randymaldonado@google.com>

vpython/application/application.go

@@ -169,7 +169,7 @@ func (a *Application) ParseEnvs(ctx context.Context) (err error) {
 	// Determine our VirtualEnv base directory.
 	if v, ok := e.Lookup(VirtualEnvRootENV); ok {
 		a.VpythonRoot = v
-	} else if a.VpythonRoot == "" {
+	} else {
 		cdir, err := a.userCacheDir()
 		if err != nil {
 			logging.Infof(ctx, "failed to get user cache dir: %s", err)

vpython/application/application_py3_test.go

@@ -19,7 +19,6 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
-	"runtime"
 	"strings"
 	"testing"
 
@@ -59,9 +58,11 @@ func getPythonEnvironment(ver string) *python.Environment {
 }
 
 func setupApp(ctx context.Context, app *Application) context.Context {
-	if app.VpythonRoot == "" {
-		app.VpythonRoot = testStorageDir
-	}
+	app.Arguments = append([]string{
+		"-vpython-root",
+		testStorageDir,
+	}, app.Arguments...)
+
 	app.Initialize(ctx)
 
 	So(app.ParseEnvs(ctx), ShouldBeNil)
@@ -165,27 +166,6 @@ func TestPythonBasic(t *testing.T) {
 					So(has, ShouldBeTrue)
 					So(rc, ShouldEqual, 42)
 				})
-
-				if runtime.GOOS != "windows" {
-					// See https://github.com/pypa/virtualenv/issues/1949
-					Convey("Test symlink root", func() {
-						symlinkRoot := filepath.Join(t.TempDir(), "link")
-						err := os.Symlink(testStorageDir, symlinkRoot)
-						So(err, ShouldBeNil)
-
-						c := cmd(t, &Application{
-							Arguments: []string{
-								"-vpython-spec",
-								testData("default.vpython3"),
-								"-c",
-								"print(123)",
-							},
-							VpythonRoot: symlinkRoot,
-						}, env)
-
-						So(output(c), ShouldEqual, "123")
-					})
-				}
 			})
 		}
 	})

vpython/python/bootstrap.py

@@ -16,7 +16,6 @@
 import os
 import subprocess
 import sys
-import tempfile
 
 if sys.version_info[0] > 2:
   ISOLATION_FLAG = '-I'
@@ -28,17 +27,10 @@
 # Create virtual environment in ${out} directory
 virtualenv = glob.glob(
     os.path.join(os.environ['virtualenv'], '*', 'virtualenv.py*'))[0]
-
-with tempfile.TemporaryDirectory() as d:
-  args = [
-      sys.executable, '-B', ISOLATION_FLAG,
-      # Use realpath to mitigate https://github.com/pypa/virtualenv/issues/1949
-      os.path.realpath(virtualenv),
-      '--no-download', '--always-copy', os.environ['out'],
-  ]
-  if virtualenv.endswith('.pyz'):
-    args.extend(['--app-data', d])
-  subprocess.check_call(args)
+subprocess.check_call([
+    sys.executable, '-B', ISOLATION_FLAG, virtualenv,
+    '--no-download', '--always-copy', os.environ['out']
+])
 
 # Install wheels to virtual environment
 if 'wheels' in os.environ: