added yamltool sort

cmd/yamltool/diff.go

@@ -2,10 +2,11 @@ package main
 
 import (
 	"fmt"
-	"github.com/goccy/go-yaml"
-	"github.com/spf13/cobra"
 	"os"
 	"reflect"
+
+	"github.com/goccy/go-yaml"
+	"github.com/spf13/cobra"
 )
 
 // hack to be able to compare slices and dictionires that cannot be put into a map.
@@ -45,6 +46,11 @@ func subtract(yaml2 yaml.MapSlice, yaml1 yaml.MapSlice) yaml.MapSlice {
 				v1set[strval(v)] = true
 			}
 			s := make([]any, 0)
+			// TODO
+			//   convert both slices to lists of strings
+			//   apply LCS to the list of strings with approximate equality
+			//   added elements:  -> output fully
+			//   approximately equal elements: -> when identical, skip, otherwise, output diffs (recurse)
 			for _, v2value := range v2.([]any) {
 				k2 := strval(v2value)
 				if v1set[k2] {
@@ -78,13 +84,22 @@ func diff(cmd *cobra.Command, args []string) error {
 	file1 := args[0]
 	file2 := args[1]
 
-	yaml1, err := parse(read(file1))
+	data1, err := read(file1)
 	if err != nil {
-		panic(fmt.Errorf("%s: %w", file1, err))
+		return err
 	}
-	yaml2, err := parse(read(file2))
+	data2, err := read(file2)
 	if err != nil {
-		panic(fmt.Errorf("%s: %w", file2, err))
+		return err
+	}
+
+	yaml1, err := parse(data1)
+	if err != nil {
+		return fmt.Errorf("%s: %w", file1, err)
+	}
+	yaml2, err := parse(data2)
+	if err != nil {
+		return fmt.Errorf("%s: %w", file2, err)
 	}
 
 	diff1 := subtract(yaml2, yaml1)