Sped up explode operator

pkg/yqlib/operator_anchors_aliases.go

@@ -141,31 +141,11 @@ func explodeOperator(d *dataTreeNavigator, context Context, expressionNode *Expr
 	return context, nil
 }
 
-func explodeNode(node *yaml.Node, context Context) error {
-	node.Anchor = ""
-	switch node.Kind {
-	case yaml.SequenceNode, yaml.DocumentNode:
-		for index, contentNode := range node.Content {
-			log.Debugf("exploding index %v", index)
-			errorInContent := explodeNode(contentNode, context)
-			if errorInContent != nil {
-				return errorInContent
-			}
-		}
-		return nil
-	case yaml.AliasNode:
-		log.Debugf("its an alias!")
-		if node.Alias != nil {
-			node.Kind = node.Alias.Kind
-			node.Style = node.Alias.Style
-			node.Tag = node.Alias.Tag
-			node.Content = node.Alias.Content
-			node.Value = node.Alias.Value
-			node.Alias = nil
-		}
-		return nil
-	case yaml.MappingNode:
+func reconstructAliasedMap(node *yaml.Node, context Context) error {
 	var newContent = list.New()
+	// can I short cut here by prechecking if there's an anchor in the map?
+	// no it needs to recurse in overrideEntry.
+
 	for index := 0; index < len(node.Content); index = index + 2 {
 		keyNode := node.Content[index]
 		valueNode := node.Content[index+1]
@@ -200,8 +180,62 @@ func explodeNode(node *yaml.Node, context Context) error {
 		node.Content[index] = newEl.Value.(*yaml.Node)
 		index++
 	}
-
 	return nil
+}
+
+func explodeNode(node *yaml.Node, context Context) error {
+	node.Anchor = ""
+	switch node.Kind {
+	case yaml.SequenceNode, yaml.DocumentNode:
+		for index, contentNode := range node.Content {
+			log.Debugf("exploding index %v", index)
+			errorInContent := explodeNode(contentNode, context)
+			if errorInContent != nil {
+				return errorInContent
+			}
+		}
+		return nil
+	case yaml.AliasNode:
+		log.Debugf("its an alias!")
+		if node.Alias != nil {
+			node.Kind = node.Alias.Kind
+			node.Style = node.Alias.Style
+			node.Tag = node.Alias.Tag
+			node.Content = node.Alias.Content
+			node.Value = node.Alias.Value
+			node.Alias = nil
+		}
+		return nil
+	case yaml.MappingNode:
+		// //check the map has an alias in it
+		hasAlias := false
+		for index := 0; index < len(node.Content); index = index + 2 {
+			keyNode := node.Content[index]
+			if keyNode.Value == "<<" {
+				hasAlias = true
+				break
+			}
+		}
+
+		if hasAlias {
+			// this is a slow op, which is why we want to check before running it.
+			return reconstructAliasedMap(node, context)
+		} else {
+			// this map has no aliases, but it's kids might
+			for index := 0; index < len(node.Content); index = index + 2 {
+				keyNode := node.Content[index]
+				valueNode := node.Content[index+1]
+				err := explodeNode(keyNode, context)
+				if err != nil {
+					return err
+				}
+				err = explodeNode(valueNode, context)
+				if err != nil {
+					return err
+				}
+			}
+			return nil
+		}
 	default:
 		return nil
 	}