postcss: Fix no-map vs noMap discrepancy

Fixes #6166

resources/resource_transformers/postcss/postcss_test.go

@@ -0,0 +1,39 @@
+// Copyright 2020 The Hugo Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package postcss
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+// Issue 6166
+func TestDecodeOptions(t *testing.T) {
+	assert := require.New(t)
+	opts1, err := DecodeOptions(map[string]interface{}{
+		"no-map": true,
+	})
+
+	assert.NoError(err)
+	assert.True(opts1.NoMap)
+
+	opts2, err := DecodeOptions(map[string]interface{}{
+		"noMap": true,
+	})
+
+	assert.NoError(err)
+	assert.True(opts2.NoMap)
+
+}