fixing comment https://github.com/a-h/templ/issues/87\#issuecomment-1…

…735297140

parser/v2/types.go

@@ -450,6 +450,14 @@ func writeNodes(w io.Writer, indent int, nodes []Node, block bool) error {
 	for i := 0; i < len(nodes); i++ {
 		// Terminating and leading whitespace is stripped.
 		_, isWhitespace := nodes[i].(Whitespace)
+
+		// allow a single space between StringExpressions
+		// prevents <div>{firstName} {lastName}</div> from becoming <div>{firstName}{lastName}</div>
+		if isWhitespace && !block && previousIs[StringExpression](nodes, i) && futureHasAnythingOtherThan[Whitespace](nodes, i) {
+			w.Write([]byte(" "))
+			continue
+		}
+
 		if isWhitespace && (i == 0 || i == len(nodes)-1) {
 			continue
 		}
@@ -469,6 +477,24 @@ func writeNodes(w io.Writer, indent int, nodes []Node, block bool) error {
 	return nil
 }
 
+func futureHasAnythingOtherThan[T any](nodes []Node, cur int) bool {
+	for i := cur + 1; i < len(nodes); i++ {
+		if _, ok := nodes[i].(T); !ok {
+			return true
+		}
+	}
+	return false
+}
+
+func previousIs[T any](nodes []Node, cur int) bool {
+	for i := cur; i >= 0; i-- {
+		if _, ok := nodes[i].(T); ok {
+			return true
+		}
+	}
+	return false
+}
+
 type RawElement struct {
 	Name       string
 	Attributes []Attribute

parser/v2/types_test.go

@@ -504,6 +504,42 @@ templ x() {
 	</li>
 }
 
+`,
+		},
+		{
+			name: "spacing between string expressions is kept",
+			input: ` // first line removed to make indentation clear
+package main
+
+templ x() {
+    <div>{firstName} {lastName}</div>
+}
+`,
+			expected: ` // first line removed to make indentation clear
+package main
+
+templ x() {
+	<div>{ firstName } { lastName }</div>
+}
+
+`,
+		},
+		{
+			name: "spacing between string expressions is not magically added",
+			input: ` // first line removed to make indentation clear
+package main
+
+templ x() {
+    <div>{pt1}{pt2}</div>
+}
+`,
+			expected: ` // first line removed to make indentation clear
+package main
+
+templ x() {
+	<div>{ pt1 }{ pt2 }</div>
+}
+
 `,
 		},
 	}