From 070b0517d5f05313f91d40f4455eff5f074d7961 Mon Sep 17 00:00:00 2001
From: Priya Wadhwa <priyawadhwa@google.com>
Date: Mon, 19 Mar 2018 10:42:40 -0700
Subject: [PATCH] Get escape token by parsing ENV command

---
 executor/cmd/root.go         |  4 ----
 pkg/commands/env.go          | 30 ++++++++++++++++++++++--------
 pkg/commands/env_test.go     | 18 ++++++++++++++++++
 pkg/dockerfile/dockerfile.go | 11 -----------
 4 files changed, 40 insertions(+), 23 deletions(-)

diff --git a/executor/cmd/root.go b/executor/cmd/root.go
index 974db7d26..a34a5f3cd 100644
--- a/executor/cmd/root.go
+++ b/executor/cmd/root.go
@@ -67,10 +67,6 @@ func execute() error {
 	if err != nil {
 		return err
 	}
-	// Set the escape token
-	if err := dockerfile.SetEscapeToken(d); err != nil {
-		return err
-	}
 	baseImage := stages[0].BaseName
 
 	// Unpack file system to root
diff --git a/pkg/commands/env.go b/pkg/commands/env.go
index 400fbdc6e..f7f004940 100644
--- a/pkg/commands/env.go
+++ b/pkg/commands/env.go
@@ -17,9 +17,10 @@ limitations under the License.
 package commands
 
 import (
-	"github.com/GoogleCloudPlatform/k8s-container-builder/pkg/dockerfile"
+	"bytes"
 	"github.com/containers/image/manifest"
 	"github.com/docker/docker/builder/dockerfile/instructions"
+	"github.com/docker/docker/builder/dockerfile/parser"
 	"github.com/docker/docker/builder/dockerfile/shell"
 	"github.com/sirupsen/logrus"
 	"os"
@@ -32,15 +33,20 @@ type EnvCommand struct {
 
 func (e *EnvCommand) ExecuteCommand(config *manifest.Schema2Config) error {
 	logrus.Info("cmd: ENV")
+	// The dockerfile/shell package handles processing env values
+	// It handles escape characters and supports expansion from the config.Env array
+	// Shlex handles some of the following use cases (these and more are tested in integration tests)
+	// ""a'b'c"" -> "a'b'c"
+	// "Rex\ The\ Dog \" -> "Rex The Dog"
+	// "a\"b" -> "a"b"
+	envString := envToString(e.cmd)
+	p, err := parser.Parse(bytes.NewReader([]byte(envString)))
+	if err != nil {
+		return err
+	}
+	shlex := shell.NewLex(p.EscapeToken)
 	newEnvs := e.cmd.Env
 	for index, pair := range newEnvs {
-		// The dockerfile/shell package handles processing env values
-		// It handles escape characters and supports expansion from the config.Env array
-		// Shlex handles some of the following use cases (these and more are tested in integration tests)
-		// ""a'b'c"" -> "a'b'c"
-		// "Rex\ The\ Dog \" -> "Rex The Dog"
-		// "a\"b" -> "a"b"
-		shlex := shell.NewLex(dockerfile.EscapeToken)
 		expandedValue, err := shlex.ProcessWord(pair.Value, config.Env)
 		if err != nil {
 			return err
@@ -92,6 +98,14 @@ Loop:
 	return nil
 }
 
+func envToString(cmd *instructions.EnvCommand) string {
+	env := []string{"ENV"}
+	for _, kvp := range cmd.Env {
+		env = append(env, kvp.Key+"="+kvp.Value)
+	}
+	return strings.Join(env, " ")
+}
+
 // We know that no files have changed, so return an empty array
 func (e *EnvCommand) FilesToSnapshot() []string {
 	return []string{}
diff --git a/pkg/commands/env_test.go b/pkg/commands/env_test.go
index 2399ff199..f0cccdaa4 100644
--- a/pkg/commands/env_test.go
+++ b/pkg/commands/env_test.go
@@ -53,3 +53,21 @@ func TestUpdateEnvConfig(t *testing.T) {
 	updateConfigEnv(newEnvs, cfg)
 	testutil.CheckErrorAndDeepEqual(t, false, nil, expectedEnvArray, cfg.Env)
 }
+
+func TestEnvToString(t *testing.T) {
+	envCmd := &instructions.EnvCommand{
+		Env: []instructions.KeyValuePair{
+			{
+				Key:   "PATH",
+				Value: "/some/path",
+			},
+			{
+				Key:   "HOME",
+				Value: "/root",
+			},
+		},
+	}
+	expectedString := "ENV PATH=/some/path HOME=/root"
+	actualString := envToString(envCmd)
+	testutil.CheckErrorAndDeepEqual(t, false, nil, expectedString, actualString)
+}
diff --git a/pkg/dockerfile/dockerfile.go b/pkg/dockerfile/dockerfile.go
index 5e036be7c..948cffa50 100644
--- a/pkg/dockerfile/dockerfile.go
+++ b/pkg/dockerfile/dockerfile.go
@@ -23,8 +23,6 @@ import (
 	"github.com/docker/docker/builder/dockerfile/parser"
 )
 
-var EscapeToken rune
-
 // Parse parses the contents of a Dockerfile and returns a list of commands
 func Parse(b []byte) ([]instructions.Stage, error) {
 	p, err := parser.Parse(bytes.NewReader(b))
@@ -37,12 +35,3 @@ func Parse(b []byte) ([]instructions.Stage, error) {
 	}
 	return stages, err
 }
-
-func SetEscapeToken(b []byte) error {
-	p, err := parser.Parse(bytes.NewReader(b))
-	if err != nil {
-		return err
-	}
-	EscapeToken = p.EscapeToken
-	return nil
-}