IndentAny added

Author: solsw

LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2022 Oleg Subachev
+Copyright (c) 2022-2025 Oleg Subachev
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

indent.go

@@ -0,0 +1,45 @@
+package jsonhelper
+
+import (
+	"bytes"
+	"encoding/json"
+	"io"
+)
+
+// IndentRW reads JSON data from [io.Reader] and writes indented data to [io.Writer].
+// (See [json.Indent] for 'prefix' and 'indent' usage.)
+func IndentRW(r io.Reader, w io.Writer, prefix, indent string) error {
+	bb, err := io.ReadAll(r)
+	if err != nil {
+		return err
+	}
+	var buf bytes.Buffer
+	if err := json.Indent(&buf, bb, prefix, indent); err != nil {
+		return err
+	}
+	_, err = buf.WriteTo(w)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// IndentStr returns the indented form of JSON string 'j'.
+// (See [json.Indent] for 'prefix' and 'indent' usage.)
+func IndentStr(j, prefix, indent string) (string, error) {
+	var buf bytes.Buffer
+	if err := json.Indent(&buf, []byte(j), prefix, indent); err != nil {
+		return "", err
+	}
+	return buf.String(), nil
+}
+
+// IndentAny returns the indented JSON encoding of 'v' as string.
+// (See [json.Indent] for 'prefix' and 'indent' usage.)
+func IndentAny(v any, prefix, indent string) (string, error) {
+	bb, err := json.MarshalIndent(v, prefix, indent)
+	if err != nil {
+		return "", err
+	}
+	return string(bb), nil
+}

jsonhelper_test.go renamed to indent_test.go

@@ -33,23 +33,23 @@ func TestIndentRW(t *testing.T) {
 				prefix: "",
 				indent: "  ",
 			},
-			want: "{\n  \"i\": 1,\n  \"s\": \"string\"\n}\n",
+			want: "{\n  \"i\": 1,\n  \"s\": \"string\"\n}",
 		},
 		{name: "2",
 			args: args{
 				r:      strings.NewReader(`[{"i":1,"s":"one"}]`),
 				prefix: "",
 				indent: "  ",
 			},
-			want: "[\n  {\n    \"i\": 1,\n    \"s\": \"one\"\n  }\n]\n",
+			want: "[\n  {\n    \"i\": 1,\n    \"s\": \"one\"\n  }\n]",
 		},
 		{name: "3",
 			args: args{
 				r:      strings.NewReader(`[{"i":1,"s":"one"},{"i":2,"s":"two"}]`),
 				prefix: "",
 				indent: "  ",
 			},
-			want: "[\n  {\n    \"i\": 1,\n    \"s\": \"one\"\n  },\n  {\n    \"i\": 2,\n    \"s\": \"two\"\n  }\n]\n",
+			want: "[\n  {\n    \"i\": 1,\n    \"s\": \"one\"\n  },\n  {\n    \"i\": 2,\n    \"s\": \"two\"\n  }\n]",
 		},
 	}
 	for _, tt := range tests {
@@ -68,7 +68,7 @@ func TestIndentRW(t *testing.T) {
 
 func TestIndentStr(t *testing.T) {
 	type args struct {
-		json   string
+		j      string
 		prefix string
 		indent string
 	}
@@ -79,18 +79,57 @@ func TestIndentStr(t *testing.T) {
 	}{
 		{name: "1",
 			args: args{
-				json:   `{"i":1,"s":"string"}`,
+				j:      `{"i":1,"s":"string"}`,
 				prefix: "",
 				indent: "  ",
 			},
-			want: "{\n  \"i\": 1,\n  \"s\": \"string\"\n}\n",
+			want: "{\n  \"i\": 1,\n  \"s\": \"string\"\n}",
 		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			if got, _ := IndentStr(tt.args.json, tt.args.prefix, tt.args.indent); got != tt.want {
+			got, _ := IndentStr(tt.args.j, tt.args.prefix, tt.args.indent)
+			if got != tt.want {
 				t.Errorf("IndentStr() = %v, want %v", got, tt.want)
 			}
 		})
 	}
 }
+
+func TestIndentAny(t *testing.T) {
+	type args struct {
+		v      any
+		prefix string
+		indent string
+	}
+	tests := []struct {
+		name    string
+		args    args
+		want    string
+		wantErr bool
+	}{
+		{name: "1",
+			args: args{
+				v: struct {
+					I int    `json:"i"`
+					S string `json:"s"`
+				}{I: 1, S: "string"},
+				prefix: "",
+				indent: "  ",
+			},
+			want: "{\n  \"i\": 1,\n  \"s\": \"string\"\n}",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := IndentAny(tt.args.v, tt.args.prefix, tt.args.indent)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("IndentAny() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if got != tt.want {
+				t.Errorf("IndentAny() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}