feat(parser/renderer): support email autolinks (#1056)

Fixes #1055

Signed-off-by: Xavier Coulon <[email protected]>

pkg/parser/document_preprocessing.go

@@ -214,7 +214,7 @@ func (c *conditions) eval() bool {
 }
 
 func contentOf(ctx *ParseContext, incl *types.FileInclusion) ([]byte, bool, error) {
-	path := incl.Location.Stringify()
+	path := incl.Location.ToString()
 	currentDir := filepath.Dir(ctx.filename)
 	filename := filepath.Join(currentDir, path)
 

pkg/parser/document_processing_apply_substitutions.go

@@ -542,11 +542,19 @@ func reparseAttributesInElements(elements []interface{}, subs []string, opts ...
 func reparseAttributes(e types.WithAttributes, subs []string, opts ...Option) error {
 	attributes := e.GetAttributes()
 	if log.IsLevelEnabled(log.DebugLevel) {
-		log.Debugf("reparsing attributes in %s", spew.Sdump(attributes))
+		log.Debugf("reparsing attributes with subs='%s' in %s", strings.Join(subs, ","), spew.Sdump(attributes))
 	}
 	for k, v := range attributes {
 		switch k {
-		case types.AttrTitle, types.AttrXRefLabel, types.AttrInlineLinkText:
+		case types.AttrTitle, types.AttrXRefLabel:
+			v, err := ReparseAttributeValue(v, subs, opts...)
+			if err != nil {
+				return err
+			}
+			attributes[k] = types.Reduce(v)
+		case types.AttrInlineLinkText:
+			// same as above, but do not allow for inline macros (eg: links)
+			subs = removeSubstitution(subs, Macros)
 			v, err := ReparseAttributeValue(v, subs, opts...)
 			if err != nil {
 				return err
@@ -870,6 +878,18 @@ func substitutions(s string) ([]string, error) {
 	}
 }
 
+// removes the given `sub` from the given `subs`
+func removeSubstitution(subs []string, sub string) []string {
+	result := make([]string, 0, len(subs))
+	for _, s := range subs {
+		if s == sub {
+			continue
+		}
+		result = append(result, s)
+	}
+	return result
+}
+
 const (
 	// enabledSubstitutions the key in which enabled substitutions are stored in the parser's GlobalStore
 	enabledSubstitutions string = "enabled_substitutions"

pkg/parser/link_test.go

@@ -185,6 +185,51 @@ a link to <{example}>.`
 			})
 		})
 
+		Context("email autolinks", func() {
+
+			It("valid email in paragraph", func() {
+				source := `write to [email protected].`
+				expected := &types.Document{
+					Elements: []interface{}{
+						&types.Paragraph{
+							Elements: []interface{}{
+								&types.StringElement{
+									Content: "write to ",
+								},
+								&types.InlineLink{
+									Location: &types.Location{
+										Scheme: "mailto:",
+										Path:   "[email protected]",
+									},
+								},
+								&types.StringElement{
+									Content: ".",
+								},
+							},
+						},
+					},
+				}
+				Expect(ParseDocument(source)).To(MatchDocument(expected))
+			})
+
+			It("invalid email in paragraph", func() {
+				source := `write to [email protected].`
+				expected := &types.Document{
+					Elements: []interface{}{
+						&types.Paragraph{
+							Elements: []interface{}{
+								&types.StringElement{
+									Content: "write to [email protected].",
+								},
+							},
+						},
+					},
+				}
+				Expect(ParseDocument(source)).To(MatchDocument(expected))
+			})
+
+		})
+
 		Context("external links", func() {
 
 			It("without text", func() {
@@ -1740,5 +1785,6 @@ title]`
 				Expect(ParseDocument(source)).To(MatchDocument(expected))
 			})
 		})
+
 	})
 })