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

See #5371

1 files changed, 99 insertions, 0 deletions

diff --git a/common/text/position.go b/common/text/position.go
new file mode 100644
index 000000000..0c43c5ae7
--- /dev/null
+++ b/common/text/position.go
@@ -0,0 +1,99 @@
+// 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 (
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/gohugoio/hugo/common/terminal"
+)
+
+// Positioner represents a thing that knows its position in a text file or stream,
+// typically an error.
+type Positioner interface {
+	Position() Position
+}
+
+// Position holds a source position in a text file or stream.
+type Position struct {
+	Filename     string // filename, if any
+	Offset       int    // byte offset, starting at 0. It's set to -1 if not provided.
+	LineNumber   int    // line number, starting at 1
+	ColumnNumber int    // column number, starting at 1 (character count per line)
+}
+
+func (pos Position) String() string {
+	if pos.Filename == "" {
+		pos.Filename = "<stream>"
+	}
+	return positionStringFormatfunc(pos)
+}
+
+// IsValid returns true if line number is > 0.
+func (pos Position) IsValid() bool {
+	return pos.LineNumber > 0
+}
+
+var positionStringFormatfunc func(p Position) string
+
+func createPositionStringFormatter(formatStr string) func(p Position) string {
+
+	if formatStr == "" {
+		formatStr = "\":file::line::col\""
+	}
+
+	var identifiers = []string{":file", ":line", ":col"}
+	var identifiersFound []string
+
+	for i := range formatStr {
+		for _, id := range identifiers {
+			if strings.HasPrefix(formatStr[i:], id) {
+				identifiersFound = append(identifiersFound, id)
+			}
+		}
+	}
+
+	replacer := strings.NewReplacer(":file", "%s", ":line", "%d", ":col", "%d")
+	format := replacer.Replace(formatStr)
+
+	f := func(pos Position) string {
+		args := make([]interface{}, len(identifiersFound))
+		for i, id := range identifiersFound {
+			switch id {
+			case ":file":
+				args[i] = pos.Filename
+			case ":line":
+				args[i] = pos.LineNumber
+			case ":col":
+				args[i] = pos.ColumnNumber
+			}
+		}
+
+		msg := fmt.Sprintf(format, args...)
+
+		if terminal.IsTerminal(os.Stdout) {
+			return terminal.Notice(msg)
+		}
+
+		return msg
+	}
+
+	return f
+}
+
+func init() {
+	positionStringFormatfunc = createPositionStringFormatter(os.Getenv("HUGO_FILE_LOG_FORMAT"))
+}