Add file (line/col) info to ref/relref errors

See #5371

common/text/position_test.go

@@ -0,0 +1,33 @@
+// Copyright 2018 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 text
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestPositionStringFormatter(t *testing.T) {
+	assert := require.New(t)
+
+	pos := Position{Filename: "/my/file.txt", LineNumber: 12, ColumnNumber: 13, Offset: 14}
+
+	assert.Equal("/my/file.txt|13|12", createPositionStringFormatter(":file|:col|:line")(pos))
+	assert.Equal("13|/my/file.txt|12", createPositionStringFormatter(":col|:file|:line")(pos))
+	assert.Equal("好:13", createPositionStringFormatter("好::col")(pos))
+	assert.Equal("\"/my/file.txt:12:13\"", createPositionStringFormatter("")(pos))
+	assert.Equal("\"/my/file.txt:12:13\"", pos.String())
+
+}