Generic ast (#1829)

Remove dependency on yaml.Node for internal AST representation. Yaml decoder is now just another decoder.

pkg/yqlib/encoder_sh.go

@@ -5,8 +5,6 @@ import (
 	"io"
 	"regexp"
 	"strings"
-
-	yaml "gopkg.in/yaml.v3"
 )
 
 var unsafeChars = regexp.MustCompile(`[^\w@%+=:,./-]`)
@@ -31,13 +29,12 @@ func (e *shEncoder) PrintLeadingContent(writer io.Writer, content string) error
 	return nil
 }
 
-func (e *shEncoder) Encode(writer io.Writer, originalNode *yaml.Node) error {
-	node := unwrapDoc(originalNode)
-	if guessTagFromCustomType(node) != "!!str" {
+func (e *shEncoder) Encode(writer io.Writer, node *CandidateNode) error {
+	if node.guessTagFromCustomType() != "!!str" {
 		return fmt.Errorf("cannot encode %v as URI, can only operate on strings. Please first pipe through another encoding operator to convert the value to a string", node.Tag)
 	}
 
-	return writeString(writer, e.encode(originalNode.Value))
+	return writeString(writer, e.encode(node.Value))
 }
 
 // put any (shell-unsafe) characters into a single-quoted block, close the block lazily