diff --git a/command/autocomplete.go b/command/autocomplete.go
index cc1ad145b..1ce90e4c9 100644
--- a/command/autocomplete.go
+++ b/command/autocomplete.go
@@ -2,7 +2,6 @@ package command
 
 import (
 	"github.com/posener/complete"
-	"github.com/posener/complete/match"
 )
 
 // This file contains some re-usable predictors for auto-complete. The
@@ -63,17 +62,6 @@ func (m *Meta) completePredictWorkspaceName() complete.Predictor {
 		}
 
 		names, _ := b.States()
-
-		if a.Last != "" {
-			// filter for names that match the prefix only
-			filtered := make([]string, 0, len(names))
-			for _, name := range names {
-				if match.Prefix(name, a.Last) {
-					filtered = append(filtered, name)
-				}
-			}
-			names = filtered
-		}
 		return names
 	})
 }
diff --git a/command/autocomplete_test.go b/command/autocomplete_test.go
index 7a799ac99..865afcbea 100644
--- a/command/autocomplete_test.go
+++ b/command/autocomplete_test.go
@@ -28,33 +28,11 @@ func TestMetaCompletePredictWorkspaceName(t *testing.T) {
 
 	predictor := meta.completePredictWorkspaceName()
 
-	t.Run("no prefix", func(t *testing.T) {
-		got := predictor.Predict(complete.Args{
-			Last: "",
-		})
-		want := []string{"default"}
-		if !reflect.DeepEqual(got, want) {
-			t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, want)
-		}
-	})
-
-	t.Run("prefix that matches", func(t *testing.T) {
-		got := predictor.Predict(complete.Args{
-			Last: "def",
-		})
-		want := []string{"default"}
-		if !reflect.DeepEqual(got, want) {
-			t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, want)
-		}
-	})
-
-	t.Run("prefix that doesn't match", func(t *testing.T) {
-		got := predictor.Predict(complete.Args{
-			Last: "x",
-		})
-		want := []string{}
-		if !reflect.DeepEqual(got, want) {
-			t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, want)
-		}
+	got := predictor.Predict(complete.Args{
+		Last: "",
 	})
+	want := []string{"default"}
+	if !reflect.DeepEqual(got, want) {
+		t.Errorf("wrong result\ngot:  %#v\nwant: %#v", got, want)
+	}
 }
diff --git a/vendor/github.com/posener/complete/args.go b/vendor/github.com/posener/complete/args.go
index 73c356d76..1ba4d6919 100644
--- a/vendor/github.com/posener/complete/args.go
+++ b/vendor/github.com/posener/complete/args.go
@@ -3,6 +3,8 @@ package complete
 import (
 	"os"
 	"path/filepath"
+	"strings"
+	"unicode"
 )
 
 // Args describes command line arguments
@@ -37,16 +39,41 @@ func (a Args) Directory() string {
 	return fixPathForm(a.Last, dir)
 }
 
-func newArgs(line []string) Args {
-	completed := removeLast(line[1:])
+func newArgs(line string) Args {
+	var (
+		all       []string
+		completed []string
+	)
+	parts := splitFields(line)
+	if len(parts) > 0 {
+		all = parts[1:]
+		completed = removeLast(parts[1:])
+	}
 	return Args{
-		All:           line[1:],
+		All:           all,
 		Completed:     completed,
-		Last:          last(line),
+		Last:          last(parts),
 		LastCompleted: last(completed),
 	}
 }
 
+func splitFields(line string) []string {
+	parts := strings.Fields(line)
+	if len(line) > 0 && unicode.IsSpace(rune(line[len(line)-1])) {
+		parts = append(parts, "")
+	}
+	parts = splitLastEqual(parts)
+	return parts
+}
+
+func splitLastEqual(line []string) []string {
+	if len(line) == 0 {
+		return line
+	}
+	parts := strings.Split(line[len(line)-1], "=")
+	return append(line[:len(line)-1], parts...)
+}
+
 func (a Args) from(i int) Args {
 	if i > len(a.All) {
 		i = len(a.All)
@@ -67,9 +94,9 @@ func removeLast(a []string) []string {
 	return a
 }
 
-func last(args []string) (last string) {
-	if len(args) > 0 {
-		last = args[len(args)-1]
+func last(args []string) string {
+	if len(args) == 0 {
+		return ""
 	}
-	return
+	return args[len(args)-1]
 }
diff --git a/vendor/github.com/posener/complete/command.go b/vendor/github.com/posener/complete/command.go
index eeeb9e027..82d37d529 100644
--- a/vendor/github.com/posener/complete/command.go
+++ b/vendor/github.com/posener/complete/command.go
@@ -1,7 +1,5 @@
 package complete
 
-import "github.com/posener/complete/match"
-
 // Command represents a command line
 // It holds the data that enables auto completion of command line
 // Command can also be a sub command.
@@ -25,9 +23,9 @@ type Command struct {
 }
 
 // Predict returns all possible predictions for args according to the command struct
-func (c *Command) Predict(a Args) (predictions []string) {
-	predictions, _ = c.predict(a)
-	return
+func (c *Command) Predict(a Args) []string {
+	options, _ := c.predict(a)
+	return options
 }
 
 // Commands is the type of Sub member, it maps a command name to a command struct
@@ -36,9 +34,7 @@ type Commands map[string]Command
 // Predict completion of sub command names names according to command line arguments
 func (c Commands) Predict(a Args) (prediction []string) {
 	for sub := range c {
-		if match.Prefix(sub, a.Last) {
-			prediction = append(prediction, sub)
-		}
+		prediction = append(prediction, sub)
 	}
 	return
 }
@@ -49,9 +45,14 @@ type Flags map[string]Predictor
 // Predict completion of flags names according to command line arguments
 func (f Flags) Predict(a Args) (prediction []string) {
 	for flag := range f {
-		if match.Prefix(flag, a.Last) {
-			prediction = append(prediction, flag)
+		// If the flag starts with a hyphen, we avoid emitting the prediction
+		// unless the last typed arg contains a hyphen as well.
+		flagHyphenStart := len(flag) != 0 && flag[0] == '-'
+		lastHyphenStart := len(a.Last) != 0 && a.Last[0] == '-'
+		if flagHyphenStart && !lastHyphenStart {
+			continue
 		}
+		prediction = append(prediction, flag)
 	}
 	return
 }
@@ -73,6 +74,10 @@ func (c *Command) predict(a Args) (options []string, only bool) {
 			if only {
 				return
 			}
+
+			// We matched so stop searching. Continuing to search can accidentally
+			// match a subcommand with current set of commands, see issue #46.
+			break
 		}
 	}
 
diff --git a/vendor/github.com/posener/complete/complete.go b/vendor/github.com/posener/complete/complete.go
index 1df66170b..185d1e8bd 100644
--- a/vendor/github.com/posener/complete/complete.go
+++ b/vendor/github.com/posener/complete/complete.go
@@ -8,10 +8,11 @@ package complete
 import (
 	"flag"
 	"fmt"
+	"io"
 	"os"
-	"strings"
 
 	"github.com/posener/complete/cmd"
+	"github.com/posener/complete/match"
 )
 
 const (
@@ -23,6 +24,7 @@ const (
 type Complete struct {
 	Command Command
 	cmd.CLI
+	Out io.Writer
 }
 
 // New creates a new complete command.
@@ -34,6 +36,7 @@ func New(name string, command Command) *Complete {
 	return &Complete{
 		Command: command,
 		CLI:     cmd.CLI{Name: name},
+		Out:     os.Stdout,
 	}
 }
 
@@ -59,28 +62,34 @@ func (c *Complete) Complete() bool {
 		return c.CLI.Run()
 	}
 	Log("Completing line: %s", line)
-
 	a := newArgs(line)
-
+	Log("Completing last field: %s", a.Last)
 	options := c.Command.Predict(a)
+	Log("Options: %s", options)
 
-	Log("Completion: %s", options)
-	output(options)
+	// filter only options that match the last argument
+	matches := []string{}
+	for _, option := range options {
+		if match.Prefix(option, a.Last) {
+			matches = append(matches, option)
+		}
+	}
+	Log("Matches: %s", matches)
+	c.output(matches)
 	return true
 }
 
-func getLine() ([]string, bool) {
+func getLine() (string, bool) {
 	line := os.Getenv(envComplete)
 	if line == "" {
-		return nil, false
+		return "", false
 	}
-	return strings.Split(line, " "), true
+	return line, true
 }
 
-func output(options []string) {
-	Log("")
+func (c *Complete) output(options []string) {
 	// stdout of program defines the complete options
 	for _, option := range options {
-		fmt.Println(option)
+		fmt.Fprintln(c.Out, option)
 	}
 }
diff --git a/vendor/github.com/posener/complete/predict_set.go b/vendor/github.com/posener/complete/predict_set.go
index 8fc59d714..fa4a34ae4 100644
--- a/vendor/github.com/posener/complete/predict_set.go
+++ b/vendor/github.com/posener/complete/predict_set.go
@@ -1,7 +1,5 @@
 package complete
 
-import "github.com/posener/complete/match"
-
 // PredictSet expects specific set of terms, given in the options argument.
 func PredictSet(options ...string) Predictor {
 	return predictSet(options)
@@ -9,11 +7,6 @@ func PredictSet(options ...string) Predictor {
 
 type predictSet []string
 
-func (p predictSet) Predict(a Args) (prediction []string) {
-	for _, m := range p {
-		if match.Prefix(m, a.Last) {
-			prediction = append(prediction, m)
-		}
-	}
-	return
+func (p predictSet) Predict(a Args) []string {
+	return p
 }
diff --git a/vendor/vendor.json b/vendor/vendor.json
index 94ee9291f..9d1a12adf 100644
--- a/vendor/vendor.json
+++ b/vendor/vendor.json
@@ -2007,10 +2007,12 @@
 			"revisionTime": "2017-05-05T04:36:39Z"
 		},
 		{
-			"checksumSHA1": "6OEUkwOM0qgI6YxR+BDEn6YMvpU=",
+			"checksumSHA1": "Nt4Ol6ZM2n0XD5zatxjwEYBpQnw=",
 			"path": "github.com/posener/complete",
-			"revision": "f4461a52b6329c11190f11fe3384ec8aa964e21c",
-			"revisionTime": "2017-07-30T19:30:24Z"
+			"revision": "dc2bc5a81accba8782bebea28628224643a8286a",
+			"revisionTime": "2017-11-04T09:57:02Z",
+			"version": "=v1.1",
+			"versionExact": "v1.1"
 		},
 		{
 			"checksumSHA1": "NB7uVS0/BJDmNu68vPAlbrq4TME=",