Merge #11804

11804: cli/new: Ignore VCS directories r=abhinav a=abhinav

# Description

The following set of operations currently fail with the CLI.

    git init
    pulumi new

This is because `pulumi new` refuses to run inside
non-empty directories.

This changes `pulumi new` to ignore .git, .hg, and .bzr
files/directories when considering whether a directory is empty.

Resolves #11789

## Checklist

- [x] I have added tests that prove my fix is effective or that my feature works
- [x] I have run `make changelog` and committed the `changelog/pending/<file>` documenting my change


Co-authored-by: Abhinav Gupta <abhinav@pulumi.com>

changelog/pending/20230107--cli-new--allow-running-inside-new-git-repositories.yaml

@@ -0,0 +1,4 @@
+changes:
+- type: fix
+  scope: cli/new
+  description: Allow running inside new VCS repositories.

pkg/cmd/pulumi/new.go

@@ -506,14 +506,31 @@ func newNewCmd() *cobra.Command {
 	return cmd
 }
 
+// File or directory names that are considered invisible
+// when considering whether a directory is empty.
+var invisibleDirEntries = map[string]struct{}{
+	".git": {},
+	".hg":  {},
+	".bzr": {},
+}
+
 // errorIfNotEmptyDirectory returns an error if path is not empty.
 func errorIfNotEmptyDirectory(path string) error {
 	infos, err := os.ReadDir(path)
 	if err != nil {
 		return err
 	}
 
-	if len(infos) > 0 {
+	var nonEmpty bool
+	for _, info := range infos {
+		if _, ignore := invisibleDirEntries[info.Name()]; ignore {
+			continue
+		}
+		nonEmpty = true
+		break
+	}
+
+	if nonEmpty {
 		return fmt.Errorf("%s is not empty; "+
 			"rerun in an empty directory, pass the path to an empty directory to --dir, or use --force", path)
 	}

pkg/cmd/pulumi/new_test.go

@@ -24,6 +24,7 @@ import (
 	"github.com/pulumi/pulumi/pkg/v3/backend"
 	"github.com/pulumi/pulumi/sdk/v3/go/common/resource/config"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 //nolint:paralleltest // changes directory for process
@@ -710,3 +711,68 @@ func TestSetFail(t *testing.T) {
 		})
 	}
 }
+
+func TestErrorIfNotEmptyDirectory(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		desc  string
+		files []string
+		dirs  []string
+		ok    bool
+	}{
+		{
+			desc: "empty",
+			ok:   true,
+		},
+		{
+			desc:  "non-empty",
+			files: []string{"foo"},
+			dirs:  []string{"bar"},
+			ok:    false,
+		},
+		{
+			desc: "empty git repository",
+			dirs: []string{".git"},
+			ok:   true,
+		},
+		{
+			desc:  "non-empty git repository",
+			dirs:  []string{".git"},
+			files: []string{".gitignore"},
+			ok:    false,
+		},
+		{
+			desc: "every VCS",
+			dirs: []string{".git", ".hg", ".bzr"},
+			ok:   true,
+		},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.desc, func(t *testing.T) {
+			t.Parallel()
+
+			path := t.TempDir()
+
+			// Fill test directory with files and directories
+			// requested by the test case.
+			for _, name := range tt.dirs {
+				err := os.MkdirAll(filepath.Join(path, name), 01700)
+				require.NoError(t, err)
+			}
+			for _, name := range tt.files {
+				err := os.WriteFile(filepath.Join(path, name), nil /* body */, 0600)
+				require.NoError(t, err)
+			}
+
+			err := errorIfNotEmptyDirectory(path)
+			if tt.ok {
+				assert.NoError(t, err)
+			} else {
+				assert.Error(t, err)
+			}
+		})
+	}
+}