fix: Run expect tests on Windows with conpty pseudo-terminal (#276)

This brings together a bunch of random, partially implemented packages for support of the new(ish) Windows [`conpty`](https://devblogs.microsoft.com/commandline/windows-command-line-introducing-the-windows-pseudo-console-conpty/) API - such that we can leverage the `expect` style of CLI tests, but in a way that works in Linux/OSX `pty`s and Windows `conpty`.

These include:
- Vendoring the `go-expect` library from Netflix w/ some tweaks to work cross-platform
- Vendoring the `pty` cross-platform implementation from [waypoint-plugin-sdk](https://github.com/hashicorp/waypoint-plugin-sdk/tree/b55c787a65ff9b7d2b32cfae80681b78f8f2275e/internal/pkg/pty)
- Vendoring the `conpty` Windows-specific implementation from [waypoint-plugin-sdk](https://github.com/hashicorp/waypoint-plugin-sdk/tree/b55c787a65ff9b7d2b32cfae80681b78f8f2275e/internal/pkg/conpty)
- Adjusting the `pty` interface to work with `go-expect` + the cross-plat version

There were several limitations with the current packages:
- `go-expect` requires the same `os.File` (TTY) for input / output, but `conhost` requires separate file handles
- `conpty` does not handle input, only output
- The cross-platform `pty` didn't expose the full set of primitives needed for `console`

Therefore, the following changes were made:
- Handling of `stdin` was added to the `conpty` interface
- We weren't using the full extent of the `go-expect` interface, so some portions were removed (ie, exec'ing a process) to simplify our implementation and make it easier to extend cross-platform
- Instead of `console` exposing just a `Tty`, it exposes an `InTty` and `OutTty`, to help encapsulate the difference on Windows (on Linux, these point to the same pipe)

Future improvements:
- The `isatty` implementation doesn't support accurate detection of `conhost` pty's without an associated process. In lieu of a more robust check, I've added a `--force-tty` flag intended for test case use - that forces the CLI to run in tty mode.
- It seems the windows implementation doesn't support setting a deadline. This is needed for the expect.Timeout API, but isn't used by us yet.

Fixes #241

cli/clitest/clitest.go

@@ -2,16 +2,13 @@ package clitest
 
 import (
 	"archive/tar"
-	"bufio"
 	"bytes"
 	"errors"
 	"io"
 	"os"
 	"path/filepath"
-	"regexp"
 	"testing"
 
-	"github.com/Netflix/go-expect"
 	"github.com/spf13/cobra"
 	"github.com/stretchr/testify/require"
 
@@ -21,12 +18,6 @@ import (
 	"github.com/coder/coder/provisioner/echo"
 )
 
-var (
-	// Used to ensure terminal output doesn't have anything crazy!
-	// See: https://stackoverflow.com/a/29497680
-	stripAnsi = regexp.MustCompile("[\u001B\u009B][[\\]()#;?]*(?:(?:(?:[a-zA-Z\\d]*(?:;[a-zA-Z\\d]*)*)?\u0007)|(?:(?:\\d{1,4}(?:;\\d{0,4})*)?[\\dA-PRZcf-ntqry=><~]))")
-)
-
 // New creates a CLI instance with a configuration pointed to a
 // temporary testing directory.
 func New(t *testing.T, args ...string) (*cobra.Command, config.Root) {
@@ -55,31 +46,6 @@ func CreateProjectVersionSource(t *testing.T, responses *echo.Responses) string
 	return directory
 }
 
-// NewConsole creates a new TTY bound to the command provided.
-// All ANSI escape codes are stripped to provide clean output.
-func NewConsole(t *testing.T, cmd *cobra.Command) *expect.Console {
-	reader, writer := io.Pipe()
-	scanner := bufio.NewScanner(reader)
-	t.Cleanup(func() {
-		_ = reader.Close()
-		_ = writer.Close()
-	})
-	go func() {
-		for scanner.Scan() {
-			if scanner.Err() != nil {
-				return
-			}
-			t.Log(stripAnsi.ReplaceAllString(scanner.Text(), ""))
-		}
-	}()
-
-	console, err := expect.NewConsole(expect.WithStdout(writer))
-	require.NoError(t, err)
-	cmd.SetIn(console.Tty())
-	cmd.SetOut(console.Tty())
-	return console
-}
-
 func extractTar(t *testing.T, data []byte, directory string) {
 	reader := tar.NewReader(bytes.NewBuffer(data))
 	for {

cli/clitest/clitest_test.go

@@ -1,5 +1,3 @@
-//go:build !windows
-
 package clitest_test
 
 import (
@@ -7,6 +5,7 @@ import (
 
 	"github.com/coder/coder/cli/clitest"
 	"github.com/coder/coder/coderd/coderdtest"
+	"github.com/coder/coder/expect"
 	"github.com/stretchr/testify/require"
 	"go.uber.org/goleak"
 )
@@ -21,7 +20,7 @@ func TestCli(t *testing.T) {
 	client := coderdtest.New(t)
 	cmd, config := clitest.New(t)
 	clitest.SetupConfig(t, client, config)
-	console := clitest.NewConsole(t, cmd)
+	console := expect.NewTestConsole(t, cmd)
 	go func() {
 		err := cmd.Execute()
 		require.NoError(t, err)

cli/login.go

@@ -22,6 +22,7 @@ func login() *cobra.Command {
 		Args: cobra.ExactArgs(1),
 		RunE: func(cmd *cobra.Command, args []string) error {
 			rawURL := args[0]
+
 			if !strings.HasPrefix(rawURL, "http://") && !strings.HasPrefix(rawURL, "https://") {
 				scheme := "https"
 				if strings.HasPrefix(rawURL, "localhost") {
@@ -44,7 +45,7 @@ func login() *cobra.Command {
 				return xerrors.Errorf("has initial user: %w", err)
 			}
 			if !hasInitialUser {
-				if !isTTY(cmd.InOrStdin()) {
+				if !isTTY(cmd) {
 					return xerrors.New("the initial user cannot be created in non-interactive mode. use the API")
 				}
 				_, _ = fmt.Fprintf(cmd.OutOrStdout(), "%s Your Coder deployment hasn't been set up!\n", color.HiBlackString(">"))

cli/login_test.go

@@ -1,11 +1,10 @@
-//go:build !windows
-
 package cli_test
 
 import (
 	"testing"
 
 	"github.com/coder/coder/cli/clitest"
+	"github.com/coder/coder/expect"
 	"github.com/coder/coder/coderd/coderdtest"
 	"github.com/stretchr/testify/require"
 )
@@ -23,8 +22,11 @@ func TestLogin(t *testing.T) {
 	t.Run("InitialUserTTY", func(t *testing.T) {
 		t.Parallel()
 		client := coderdtest.New(t)
-		root, _ := clitest.New(t, "login", client.URL.String())
-		console := clitest.NewConsole(t, root)
+		// The --force-tty flag is required on Windows, because the `isatty` library does not
+		// accurately detect Windows ptys when they are not attached to a process:
+		// https://github.com/mattn/go-isatty/issues/59
+		root, _ := clitest.New(t, "login", client.URL.String(), "--force-tty")
+		console := expect.NewTestConsole(t, root)
 		go func() {
 			err := root.Execute()
 			require.NoError(t, err)

cli/projectcreate_test.go

@@ -1,5 +1,3 @@
-//go:build !windows
-
 package cli_test
 
 import (
@@ -10,6 +8,7 @@ import (
 	"github.com/coder/coder/cli/clitest"
 	"github.com/coder/coder/coderd/coderdtest"
 	"github.com/coder/coder/database"
+	"github.com/coder/coder/expect"
 	"github.com/coder/coder/provisioner/echo"
 	"github.com/coder/coder/provisionersdk/proto"
 )
@@ -27,7 +26,7 @@ func TestProjectCreate(t *testing.T) {
 		cmd, root := clitest.New(t, "projects", "create", "--directory", source, "--provisioner", string(database.ProvisionerTypeEcho))
 		clitest.SetupConfig(t, client, root)
 		_ = coderdtest.NewProvisionerDaemon(t, client)
-		console := clitest.NewConsole(t, cmd)
+		console := expect.NewTestConsole(t, cmd)
 		closeChan := make(chan struct{})
 		go func() {
 			err := cmd.Execute()
@@ -74,7 +73,7 @@ func TestProjectCreate(t *testing.T) {
 		cmd, root := clitest.New(t, "projects", "create", "--directory", source, "--provisioner", string(database.ProvisionerTypeEcho))
 		clitest.SetupConfig(t, client, root)
 		coderdtest.NewProvisionerDaemon(t, client)
-		console := clitest.NewConsole(t, cmd)
+		console := expect.NewTestConsole(t, cmd)
 		closeChan := make(chan struct{})
 		go func() {
 			err := cmd.Execute()

cli/root.go

@@ -21,6 +21,7 @@ import (
 
 const (
 	varGlobalConfig = "global-config"
+	varForceTty     = "force-tty"
 )
 
 func Root() *cobra.Command {
@@ -65,6 +66,12 @@ func Root() *cobra.Command {
 	cmd.AddCommand(users())
 
 	cmd.PersistentFlags().String(varGlobalConfig, configdir.LocalConfig("coder"), "Path to the global `coder` config directory")
+	cmd.PersistentFlags().Bool(varForceTty, false, "Force the `coder` command to run as if connected to a TTY")
+	err := cmd.PersistentFlags().MarkHidden(varForceTty)
+	if err != nil {
+		// This should never return an error, because we just added the `--force-tty`` flag prior to calling MarkHidden.
+		panic(err)
+	}
 
 	return cmd
 }
@@ -113,7 +120,16 @@ func createConfig(cmd *cobra.Command) config.Root {
 // isTTY returns whether the passed reader is a TTY or not.
 // This accepts a reader to work with Cobra's "InOrStdin"
 // function for simple testing.
-func isTTY(reader io.Reader) bool {
+func isTTY(cmd *cobra.Command) bool {
+	// If the `--force-tty` command is available, and set,
+	// assume we're in a tty. This is primarily for cases on Windows
+	// where we may not be able to reliably detect this automatically (ie, tests)
+	forceTty, err := cmd.Flags().GetBool(varForceTty)
+	if forceTty && err == nil {
+		return true
+	}
+
+	reader := cmd.InOrStdin()
 	file, ok := reader.(*os.File)
 	if !ok {
 		return false

cli/workspacecreate_test.go

@@ -1,5 +1,3 @@
-//go:build !windows
-
 package cli_test
 
 import (
@@ -7,6 +5,7 @@ import (
 
 	"github.com/coder/coder/cli/clitest"
 	"github.com/coder/coder/coderd/coderdtest"
+	"github.com/coder/coder/expect"
 	"github.com/coder/coder/provisioner/echo"
 	"github.com/coder/coder/provisionersdk/proto"
 	"github.com/stretchr/testify/require"
@@ -37,7 +36,7 @@ func TestWorkspaceCreate(t *testing.T) {
 		cmd, root := clitest.New(t, "workspaces", "create", project.Name)
 		clitest.SetupConfig(t, client, root)
 
-		console := clitest.NewConsole(t, cmd)
+		console := expect.NewTestConsole(t, cmd)
 		closeChan := make(chan struct{})
 		go func() {
 			err := cmd.Execute()