Support multiple key+value pairs for map flags.

README.md

@@ -346,6 +346,8 @@ var CLI struct {
 }
 ```
 
+For flags, multiple key+value pairs should be separated by `;` eg. `--set="key1=value1;key2=value2"`.
+
 ## Custom named decoders
 
 Kong includes a number of builtin custom type mappers. These can be used by

mapper.go

@@ -284,7 +284,16 @@ func mapDecoder(r *Registry) MapperFunc {
 			target.Set(reflect.MakeMap(target.Type()))
 		}
 		el := target.Type()
-		token := ctx.Scan.PopValue("map")
+		var childScanner *Scanner
+		if ctx.Value.Flag != nil {
+			// If decoding a flag, we need an argument.
+			childScanner = Scan(SplitEscaped(ctx.Scan.PopValue("map"), ';')...)
+		} else {
+			tokens := ctx.Scan.PopWhile(func(t Token) bool { return t.IsValue() })
+			childScanner = ScanFromTokens(tokens...)
+		}
+		for !childScanner.Peek().IsEOL() {
+			token := childScanner.PopValue("map")
 			parts := strings.SplitN(token, "=", 2)
 			if len(parts) != 2 {
 				return fmt.Errorf("expected \"<key>=<value>\" but got %q", token)
@@ -315,6 +324,7 @@ func mapDecoder(r *Registry) MapperFunc {
 			}
 
 			target.SetMapIndex(keyValue, valueValue)
+		}
 		return nil
 	}
 }

mapper_test.go

@@ -99,6 +99,16 @@ func TestMapWithNamedTypes(t *testing.T) {
 	require.Equal(t, map[string]string{"FIRST": "5s", "SECOND": "10s"}, cli.TypedKey)
 }
 
+func TestMapWithMultipleValues(t *testing.T) {
+	var cli struct {
+		Value map[string]string
+	}
+	k := mustNew(t, &cli)
+	_, err := k.Parse([]string{"--value=a=b;c=d"})
+	require.NoError(t, err)
+	require.Equal(t, map[string]string{"a": "b", "c": "d"}, cli.Value)
+}
+
 func TestURLMapper(t *testing.T) {
 	var cli struct {
 		URL *url.URL `arg:""`