fix: default selection and comment interpolation

pkg/config/vars.go

@@ -1,6 +1,7 @@
 package config
 
 import (
+	"bytes"
 	"fmt"
 	"strings"
 
@@ -45,58 +46,60 @@ func (e *YAMLEvaluator) encode(val interface{}) ([]byte, error) {
 }
 
 func (e *YAMLEvaluator) Expand(input []byte) ([]byte, error) {
-	var out []byte
-
-	done := 0
-	line := 0
-	lineStart := 0
 	tokenStart := -1
-	ll := len(input)
 
 	var token string
 
-	for i := 0; i < ll; i++ {
-		switch {
-		case input[i] == '\n':
-			line++
-
-			lineStart = i + 1
-
-			continue
+	in := bytes.Split(input, []byte{'\n'})
+	out := make([][]byte, len(in))
 
-		case tokenStart == -1:
-			if i+1 < ll && input[i] == '$' && input[i+1] == '{' {
-				i++
-				tokenStart = i
-			}
-
-		case input[i] == '}':
-			token = string(input[tokenStart+1 : i])
-			if token == "" {
-				return nil, fmt.Errorf("[%d:%d] empty expansion found", line+1, tokenStart-lineStart)
-			}
+	for l, line := range in {
+		ll := len(line)
+		done := 0
 
-			out = append(out, input[done:tokenStart-1]...)
+		lineTrimmed := bytes.TrimSpace(line)
+		if len(lineTrimmed) > 0 && lineTrimmed[0] == '#' {
+			out[l] = line
 
-			val, ok := e.getKey(token)
-			if !ok {
-				return nil, fmt.Errorf("[%d:%d] expansion value '%s' could not be evaluated", line+1, tokenStart-lineStart, token)
-			}
+			continue
+		}
 
-			valOut, err := e.encode(val)
-			if err != nil {
-				return nil, fmt.Errorf("[%d:%d] expansion value '%s' could not be marshaled\nerror: %w",
-					line+1, tokenStart-lineStart, token, err)
+		for c := range line {
+			switch {
+			case tokenStart == -1:
+				if c+1 < ll && line[c] == '$' && line[c+1] == '{' {
+					c++
+					tokenStart = c
+				}
+
+			case line[c] == '}':
+				token = string(line[tokenStart+1 : c])
+				if token == "" {
+					return nil, fmt.Errorf("[%d:%d] empty expansion found", l+1, tokenStart)
+				}
+
+				out[l] = append(out[l], line[done:tokenStart-1]...)
+
+				val, ok := e.getKey(token)
+				if !ok {
+					return nil, fmt.Errorf("[%d:%d] expansion value '%s' could not be evaluated", l+1, tokenStart, token)
+				}
+
+				valOut, err := e.encode(val)
+				if err != nil {
+					return nil, fmt.Errorf("[%d:%d] expansion value '%s' could not be marshaled\nerror: %w",
+						l+1, tokenStart, token, err)
+				}
+
+				out[l] = append(out[l], valOut...)
+
+				done = c + 1
+				tokenStart = -1
 			}
-
-			out = append(out, valOut...)
-
-			done = i + 1
-			tokenStart = -1
 		}
-	}
 
-	out = append(out, input[done:]...)
+		out[l] = append(out[l], line[done:]...)
+	}
 
-	return out, nil
+	return bytes.Join(out, []byte{'\n'}), nil
 }

pkg/plugins/client/stream.go

@@ -184,11 +184,16 @@ func (s *SenderStream) handleResponse(res *ResponseWithHeader) (handled bool, er
 	case *plugin_go.PromptSelect:
 		var input string
 
-		err = survey.AskOne(&survey.Select{
+		sel := &survey.Select{
 			Message: r.Message,
 			Options: r.Options,
-			Default: r.Default,
-		}, &input)
+		}
+
+		if r.Default != "" {
+			sel.Default = r.Default
+		}
+
+		err = survey.AskOne(sel, &input)
 		if err != nil {
 			return true, err
 		}