Avoid double-quailfying venv folder path (#6599)

* Avoid double-quailfying venv folder path

* Replace `path` with `filepath`

* Add a Python integration test to cover venv auto-creation

* Merged

* Fix spelling

Co-authored-by: Justin Van Patten <jvp@justinvp.com>

* Make AbsPath and RelPath test variants

* Fix issue on Windows backslash paths

* Debug windows test failure: more logging and aggressive YAML escaping

* Use filepath.IsAbs instead of path.IsAbs

Co-authored-by: Justin Van Patten <jvp@justinvp.com>

CHANGELOG_PENDING.md

@@ -14,9 +14,13 @@
   - Nodejs: `LocalWorkspace.pulumiVersion` - [#6580](https://github.com/pulumi/pulumi/pull/6580)
   - Python: `LocalWorkspace.pulumi_version` - [#6589](https://github.com/pulumi/pulumi/pull/6589)
   - Dotnet: `LocalWorkspace.PulumiVersion` - [#6590](https://github.com/pulumi/pulumi/pull/6590)
-  
+
+
 ### Bug Fixes
 
+- [sdk/python] Fix automatic venv creation
+  [#6599](https://github.com/pulumi/pulumi/pull/6599)
+
 - [automation/python] Fix Settings file save
   [#6605](https://github.com/pulumi/pulumi/pull/6605)
 

sdk/python/cmd/pulumi-language-python/main.go

@@ -31,7 +31,6 @@ import (
 	"math/rand"
 	"os"
 	"os/exec"
-	"path"
 	"path/filepath"
 	"strconv"
 	"strings"
@@ -191,7 +190,7 @@ func (host *pythonLanguageHost) prepareVirtualEnvironment(ctx context.Context, c
 	}
 
 	// Make sure it's an absolute path.
-	if !path.IsAbs(virtualenv) {
+	if !filepath.IsAbs(virtualenv) {
 		virtualenv = filepath.Join(cwd, virtualenv)
 	}
 
@@ -520,7 +519,7 @@ func (host *pythonLanguageHost) Run(ctx context.Context, req *pulumirpc.RunReque
 	var virtualenv string
 	if host.virtualenv != "" {
 		virtualenv = host.virtualenv
-		if !path.IsAbs(virtualenv) {
+		if !filepath.IsAbs(virtualenv) {
 			cwd, err := os.Getwd()
 			if err != nil {
 				return nil, errors.Wrap(err, "getting the working directory")

sdk/python/python.go

@@ -218,7 +218,10 @@ func InstallDependenciesWithWriters(root, venvDir string, showOutput bool, infoW
 	print("Creating virtual environment...")
 
 	// Create the virtual environment by running `python -m venv <venvDir>`.
-	venvDir = filepath.Join(root, venvDir)
+	if !filepath.IsAbs(venvDir) {
+		venvDir = filepath.Join(root, venvDir)
+	}
+
 	cmd, err := Command("-m", "venv", venvDir)
 	if err != nil {
 		return err

tests/integration/integration_python_test.go

@@ -6,14 +6,19 @@ package ints
 import (
 	"bytes"
 	"fmt"
+	"io/ioutil"
 	"os"
 	"path/filepath"
 	"runtime"
+	"strings"
 	"testing"
 
+	"github.com/stretchr/testify/assert"
+
 	"github.com/pulumi/pulumi/pkg/v2/testing/integration"
 	"github.com/pulumi/pulumi/sdk/v2/go/common/resource"
-	"github.com/stretchr/testify/assert"
+	ptesting "github.com/pulumi/pulumi/sdk/v2/go/common/testing"
+	"github.com/pulumi/pulumi/sdk/v2/python"
 )
 
 // TestEmptyPython simply tests that we can run an empty Python project.
@@ -400,3 +405,67 @@ func TestGetResourcePython(t *testing.T) {
 		AllowEmptyPreviewChanges: true,
 	})
 }
+
+// Regresses https://github.com/pulumi/pulumi/issues/6471
+func TestAutomaticVenvCreation(t *testing.T) {
+	// Do not use integration.ProgramTest to avoid automatic venv
+	// handling by test harness; we actually are testing venv
+	// handling by the pulumi CLI itself.
+
+	check := func(t *testing.T, venvPathTemplate string) {
+
+		e := ptesting.NewEnvironment(t)
+		defer func() {
+			if !t.Failed() {
+				e.DeleteEnvironment()
+			}
+		}()
+
+		venvPath := strings.ReplaceAll(venvPathTemplate, "${root}", e.RootPath)
+		t.Logf("venvPath = %s (IsAbs = %v)", venvPath, filepath.IsAbs(venvPath))
+
+		e.ImportDirectory(filepath.Join("python", "venv"))
+
+		// replace "virtualenv: venv" with "virtualenv: ${venvPath}" in Pulumi.yaml
+		pulumiYaml := filepath.Join(e.RootPath, "Pulumi.yaml")
+
+		oldYaml, err := ioutil.ReadFile(pulumiYaml)
+		if err != nil {
+			t.Error(err)
+			return
+		}
+		newYaml := []byte(strings.ReplaceAll(string(oldYaml),
+			"virtualenv: venv",
+			fmt.Sprintf("virtualenv: >-\n      %s", venvPath)))
+		if err := ioutil.WriteFile(pulumiYaml, newYaml, 0644); err != nil {
+			t.Error(err)
+			return
+		}
+
+		t.Logf("Wrote Pulumi.yaml:\n%s\n", string(newYaml))
+
+		e.RunCommand("pulumi", "login", "--cloud-url", e.LocalURL())
+		e.RunCommand("pulumi", "stack", "init", "teststack")
+		e.RunCommand("pulumi", "preview")
+
+		var absVenvPath string
+		if filepath.IsAbs(venvPath) {
+			absVenvPath = venvPath
+		} else {
+			absVenvPath = filepath.Join(e.RootPath, venvPath)
+		}
+
+		if !python.IsVirtualEnv(absVenvPath) {
+			t.Errorf("Expected a virtual environment to be created at %s but it is not there",
+				absVenvPath)
+		}
+	}
+
+	t.Run("RelativePath", func(t *testing.T) {
+		check(t, "venv")
+	})
+
+	t.Run("AbsolutePath", func(t *testing.T) {
+		check(t, filepath.Join("${root}", "absvenv"))
+	})
+}

tests/integration/python/venv/.gitignore

@@ -0,0 +1,5 @@
+*.pyc
+/.pulumi/
+/dist/
+/*.egg-info
+venv/

tests/integration/python/venv/Pulumi.yaml

@@ -0,0 +1,6 @@
+name: pulumi-python-venv
+description: A simple Python Pulumi program that needs a venv to run.
+runtime:
+  name: python
+  options:
+    virtualenv: venv

tests/integration/python/venv/__main__.py

@@ -0,0 +1,7 @@
+# Copyright 2016-2020, Pulumi Corporation.  All rights reserved.
+
+"""An example program that needs a venv to run"""
+
+import pulumi
+
+pulumi.export('foo', 'bar')

tests/integration/python/venv/requirements.txt

@@ -0,0 +1 @@
+pulumi