fix(html): keep striptags single-pass

Co-Authored-By: Virgil <virgil@lethean.io>

pipeline.go

@@ -4,6 +4,7 @@ package html
 
 import (
 	"strings"
+	"unicode"
 
 	"dappco.re/go/core/i18n/reversal"
 )
@@ -15,33 +16,39 @@ import (
 func StripTags(html string) string {
 	var b strings.Builder
 	inTag := false
-	prevSpace := true // starts true to trim leading space
+	pendingSpace := false
+	seenText := false
 	for _, r := range html {
+		if inTag {
+			if r == '>' {
+				inTag = false
+				if seenText {
+					pendingSpace = true
+				}
+			}
+			continue
+		}
+
 		if r == '<' {
 			inTag = true
 			continue
 		}
-		if r == '>' {
-			inTag = false
-			if !prevSpace {
-				b.WriteByte(' ')
-				prevSpace = true
+
+		if unicode.IsSpace(r) {
+			if seenText {
+				pendingSpace = true
 			}
 			continue
 		}
-		if !inTag {
-			if r == ' ' || r == '\t' || r == '\n' {
-				if !prevSpace {
-					b.WriteByte(' ')
-					prevSpace = true
-				}
-			} else {
-				b.WriteRune(r)
-				prevSpace = false
-			}
+
+		if pendingSpace {
+			b.WriteByte(' ')
+			pendingSpace = false
 		}
+		b.WriteRune(r)
+		seenText = true
 	}
-	return strings.TrimSpace(b.String())
+	return b.String()
 }
 
 // pipeline.go: Imprint renders a node tree to HTML, strips tags, tokenises the text,

pipeline_test.go

@@ -32,6 +32,14 @@ func TestStripTags_MultipleRegions(t *testing.T) {
 	}
 }
 
+func TestStripTags_BoundaryWhitespace(t *testing.T) {
+	got := StripTags(`<p></p><p>hello</p><p></p>`)
+	want := "hello"
+	if got != want {
+		t.Errorf("StripTags(boundary whitespace) = %q, want %q", got, want)
+	}
+}
+
 func TestStripTags_Empty(t *testing.T) {
 	got := StripTags("")
 	if got != "" {