First attempt at fixer for powershell escapes

fix/fixer.go

@@ -34,6 +34,7 @@ func init() {
 		"amazon-shutdown_behavior":   new(FixerAmazonShutdownBehavior),
 		"amazon-enhanced-networking": new(FixerAmazonEnhancedNetworking),
 		"docker-email":               new(FixerDockerEmail),
+		"powershell-escapes":         new(FixerPowerShellEscapes),
 	}
 
 	FixerOrder = []string{
@@ -51,5 +52,6 @@ func init() {
 		"amazon-shutdown_behavior",
 		"amazon-enhanced-networking",
 		"docker-email",
+		"powershell-escapes",
 	}
 }

fix/fixer_powershell_escapes.go

@@ -0,0 +1,73 @@
+package fix
+
+import (
+	"github.com/mitchellh/mapstructure"
+	"strings"
+)
+
+// FixerPowerShellEscapes removes the PowerShell escape character from user
+// environment variables and elevated username and password strings
+type FixerPowerShellEscapes struct{}
+
+func (FixerPowerShellEscapes) Fix(input map[string]interface{}) (map[string]interface{}, error) {
+	type template struct {
+		Provisioners []interface{}
+	}
+
+	var psUnescape = strings.NewReplacer(
+		"`$", "$",
+		"`\"", "\"",
+		"``", "`",
+		"`'", "'",
+	)
+
+	// Decode the input into our structure, if we can
+	var tpl template
+	if err := mapstructure.WeakDecode(input, &tpl); err != nil {
+		return nil, err
+	}
+
+	for i, raw := range tpl.Provisioners {
+		var provisioners map[string]interface{}
+		if err := mapstructure.Decode(raw, &provisioners); err != nil {
+			// Ignore errors, could be a non-map
+			continue
+		}
+
+		if ok := provisioners["type"] == "powershell"; !ok {
+			continue
+		}
+
+		if _, ok := provisioners["elevated_user"]; ok {
+			provisioners["elevated_user"] = psUnescape.Replace(provisioners["elevated_user"].(string))
+		}
+		if _, ok := provisioners["elevated_password"]; ok {
+			provisioners["elevated_password"] = psUnescape.Replace(provisioners["elevated_password"].(string))
+		}
+		if raw, ok := provisioners["environment_vars"]; ok {
+			var env_vars []string
+			if err := mapstructure.Decode(raw, &env_vars); err != nil {
+				continue
+			}
+			env_vars_unescaped := make([]interface{}, len(env_vars))
+			for j, env_var := range env_vars {
+				env_vars_unescaped[j] = psUnescape.Replace(env_var)
+			}
+			// Replace with unescaped environment variables
+			provisioners["environment_vars"] = env_vars_unescaped
+		}
+
+		// Write all changes back to template
+		tpl.Provisioners[i] = provisioners
+	}
+
+	if len(tpl.Provisioners) > 0 {
+		input["provisioners"] = tpl.Provisioners
+	}
+
+	return input, nil
+}
+
+func (FixerPowerShellEscapes) Synopsis() string {
+	return `Removes PowerShell escapes from user env vars and elevated username and password strings`
+}