fix: strip newlines at the end of component files (#406)

virchau13 · Nate Moore · natemoo-re · web-flow · commit 702e84898fcb · 2022-05-23T11:00:13.000-05:00
* fix: strip newlines at the end of component files

* refactor: trim trailing space in transform

* test: add explicit space preservation test

* Update chilly-chairs-enjoy.md

Co-authored-by: Nate Moore &lt;nate@skypack.dev&gt;
Co-authored-by: Nate Moore &lt;natemoo-re@users.noreply.github.com&gt;
diff --git a/.changeset/chilly-chairs-enjoy.md b/.changeset/chilly-chairs-enjoy.md
@@ -0,0 +1,5 @@
+---
+'@astrojs/compiler': minor
+---
+
+Trailing space at the end of Astro files is now stripped from Component output.
diff --git a/internal/transform/transform.go b/internal/transform/transform.go
@@ -3,6 +3,7 @@ package transform
 import (
 	"fmt"
 	"strings"
+	"unicode"
 
 	astro "github.com/withastro/compiler/internal"
 	"github.com/withastro/compiler/internal/loc"
@@ -51,6 +52,8 @@ func Transform(doc *astro.Node, opts TransformOptions) *astro.Node {
 		doc.AppendChild(empty)
 	}
 
+	TrimTrailingSpace(doc)
+
 	return doc
 }
 
@@ -126,6 +129,33 @@ func NormalizeSetDirectives(doc *astro.Node) {
 	}
 }
 
+func TrimTrailingSpace(doc *astro.Node) {
+	if doc.LastChild == nil {
+		return
+	}
+
+	if doc.LastChild.Type == astro.TextNode {
+		doc.LastChild.Data = strings.TrimRightFunc(doc.LastChild.Data, unicode.IsSpace)
+		return
+	}
+
+	n := doc.LastChild
+	for i := 0; i < 2; i++ {
+		// Loop through implicit nodes to find final trailing text node (html > body > #text)
+		if n != nil && n.Type == astro.ElementNode && IsImplictNode(n) {
+			n = n.LastChild
+			continue
+		} else {
+			n = nil
+			break
+		}
+	}
+
+	if n != nil && n.Type == astro.TextNode {
+		n.Data = strings.TrimRightFunc(n.Data, unicode.IsSpace)
+	}
+}
+
 // TODO: cleanup sibling whitespace after removing scripts/styles
 // func removeSiblingWhitespace(n *astro.Node) {
 // 	if c := n.NextSibling; c != nil && c.Type == astro.TextNode {
diff --git a/internal/transform/transform_test.go b/internal/transform/transform_test.go
@@ -198,3 +198,51 @@ func TestFullTransform(t *testing.T) {
 		})
 	}
 }
+
+func TestTransformTrailingSpace(t *testing.T) {
+	tests := []struct {
+		name   string
+		source string
+		want   string
+	}{
+		{
+			name:   "component with trailing space",
+			source: "<h1>Hello world</h1>\n\n\t ",
+			want:   `<h1>Hello world</h1>`,
+		},
+		{
+			name:   "component with no trailing space",
+			source: "<h1>Hello world</h1>",
+			want:   "<h1>Hello world</h1>",
+		},
+		{
+			name:   "component with leading and trailing space",
+			source: "<span/>\n\n\t <h1>Hello world</h1>\n\n\t ",
+			want:   "<span></span>\n\n\t <h1>Hello world</h1>",
+		},
+		{
+			name:   "html with explicit space",
+			source: "<html><body>\n\n\n</body></html>",
+			want:   "<html><body>\n\n\n</body></html>",
+		},
+	}
+	var b strings.Builder
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			b.Reset()
+			doc, err := astro.Parse(strings.NewReader(tt.source))
+			if err != nil {
+				t.Error(err)
+			}
+			ExtractStyles(doc)
+			// Clear doc.Styles to avoid scoping behavior, we're not testing that here
+			doc.Styles = make([]*astro.Node, 0)
+			Transform(doc, TransformOptions{})
+			astro.PrintToSource(&b, doc)
+			got := b.String()
+			if tt.want != got {
+				t.Errorf("\nFAIL: %s\n  want: %s\n  got:  %s", tt.name, tt.want, got)
+			}
+		})
+	}
+}
diff --git a/packages/compiler/deno/astro.wasm b/packages/compiler/deno/astro.wasm

-Original file line number
+Diff line change
@@ @@ -0,0 +1,5 @@ @@
 +---
 +'@astrojs/compiler': minor
 +---
++
 +Trailing space at the end of Astro files is now stripped from Component output.