Use Node.ID for anchor ID

Fixes #2057

2 files changed, 15 insertions, 14 deletions

diff --git a/helpers/content.go b/helpers/content.go
index f60349055..3ac91b360 100644
--- a/helpers/content.go
+++ b/helpers/content.go
@@ -23,6 +23,10 @@ import (
 	"os/exec"
 	"unicode/utf8"
 
+	"fmt"
+	"strings"
+	"sync"
+
 	"github.com/miekg/mmark"
 	"github.com/mitchellh/mapstructure"
 	"github.com/russross/blackfriday"
@@ -30,9 +34,6 @@ import (
 	bp "github.com/spf13/hugo/bufferpool"
 	jww "github.com/spf13/jwalterweatherman"
 	"github.com/spf13/viper"
-
-	"strings"
-	"sync"
 )
 
 // SummaryLength is the length of the summary that Hugo extracts from a content.
@@ -167,11 +168,11 @@ func getHTMLRenderer(defaultFlags int, ctx *RenderingContext) blackfriday.Render
 		FootnoteReturnLinkContents: viper.GetString("FootnoteReturnLinkContents"),
 	}
 
-	b := len(ctx.DocumentID) != 0
+	b := ctx.DocumentID != 0
 
 	if b && !ctx.getConfig().PlainIDAnchors {
-		renderParameters.FootnoteAnchorPrefix = ctx.DocumentID + ":" + renderParameters.FootnoteAnchorPrefix
-		renderParameters.HeaderIDSuffix = ":" + ctx.DocumentID
+		renderParameters.FootnoteAnchorPrefix = fmt.Sprintf("%d:%s", ctx.DocumentID, renderParameters.FootnoteAnchorPrefix)
+		renderParameters.HeaderIDSuffix = fmt.Sprintf(":%d", ctx.DocumentID)
 	}
 
 	htmlFlags := defaultFlags
@@ -258,10 +259,10 @@ func getMmarkHTMLRenderer(defaultFlags int, ctx *RenderingContext) mmark.Rendere
 		FootnoteReturnLinkContents: viper.GetString("FootnoteReturnLinkContents"),
 	}
 
-	b := len(ctx.DocumentID) != 0
+	b := ctx.DocumentID != 0
 
 	if b && !ctx.getConfig().PlainIDAnchors {
-		renderParameters.FootnoteAnchorPrefix = ctx.DocumentID + ":" + renderParameters.FootnoteAnchorPrefix
+		renderParameters.FootnoteAnchorPrefix = fmt.Sprintf("%d:%s", ctx.DocumentID, renderParameters.FootnoteAnchorPrefix)
 		// renderParameters.HeaderIDSuffix = ":" + ctx.DocumentId
 	}
 
@@ -343,7 +344,7 @@ func ExtractTOC(content []byte) (newcontent []byte, toc []byte) {
 type RenderingContext struct {
 	Content      []byte
 	PageFmt      string
-	DocumentID   string
+	DocumentID   int
 	Config       *Blackfriday
 	FileResolver FileResolverFunc
 	LinkResolver LinkResolverFunc
diff --git a/helpers/content_test.go b/helpers/content_test.go
index a89b4992e..347884f0a 100644
--- a/helpers/content_test.go
+++ b/helpers/content_test.go
@@ -172,15 +172,15 @@ func TestGetHTMLRendererAllFlags(t *testing.T) {
 
 func TestGetHTMLRendererAnchors(t *testing.T) {
 	ctx := &RenderingContext{}
-	ctx.DocumentID = "testid"
+	ctx.DocumentID = 123
 	ctx.Config = ctx.getConfig()
 	ctx.Config.PlainIDAnchors = false
 
 	actualRenderer := getHTMLRenderer(0, ctx)
 	headerBuffer := &bytes.Buffer{}
 	footnoteBuffer := &bytes.Buffer{}
-	expectedFootnoteHref := []byte("href=\"#fn:testid:href\"")
-	expectedHeaderID := []byte("<h1 id=\"id:testid\"></h1>\n")
+	expectedFootnoteHref := []byte("href=\"#fn:123:href\"")
+	expectedHeaderID := []byte("<h1 id=\"id:123\"></h1>\n")
 
 	actualRenderer.Header(headerBuffer, func() bool { return true }, 1, "id")
 	actualRenderer.FootnoteRef(footnoteBuffer, []byte("href"), 1)
@@ -196,14 +196,14 @@ func TestGetHTMLRendererAnchors(t *testing.T) {
 
 func TestGetMmarkHTMLRenderer(t *testing.T) {
 	ctx := &RenderingContext{}
-	ctx.DocumentID = "testid"
+	ctx.DocumentID = 321
 	ctx.Config = ctx.getConfig()
 	ctx.Config.PlainIDAnchors = false
 	actualRenderer := getMmarkHTMLRenderer(0, ctx)
 
 	headerBuffer := &bytes.Buffer{}
 	footnoteBuffer := &bytes.Buffer{}
-	expectedFootnoteHref := []byte("href=\"#fn:testid:href\"")
+	expectedFootnoteHref := []byte("href=\"#fn:321:href\"")
 	expectedHeaderID := []byte("<h1 id=\"id\"></h1>")
 
 	actualRenderer.FootnoteRef(footnoteBuffer, []byte("href"), 1)