fix: comments and strings inside of expression attributes (#149)

* fix: comments and strings inside of expression attributes

* refactor: remove dead code

.changeset/new-socks-punch.md

@@ -0,0 +1,5 @@
+---
+'@astrojs/compiler': patch
+---
+
+Fix comments and strings inside of attribute expressions

internal/token.go

@@ -1231,6 +1231,20 @@ func (z *Tokenizer) readTagAttrExpression() {
 			return
 		}
 		switch c {
+		// Handle comments, strings within attrs
+		case '/', '"', '\'', '`':
+			end := z.data.End
+			if c == '/' {
+				next := z.readByte()
+				if next == '/' {
+					panic("Block comments (//) are not allowed inside of expressions")
+				}
+				z.readCommentOrRegExp()
+			} else {
+				z.readString(c)
+			}
+			z.raw.End = z.data.End
+			z.data.End = end
 		case '{':
 			z.attrExpressionStack++
 		case '}':

internal/token_test.go

@@ -122,6 +122,21 @@ func TestBasic(t *testing.T) {
 			`<div>{ value }</div>`,
 			[]TokenType{StartTagToken, StartExpressionToken, TextToken, EndExpressionToken, EndTagToken},
 		},
+		{
+			"attribute expression with quoted braces",
+			`<div value={"{"} />`,
+			[]TokenType{SelfClosingTagToken},
+		},
+		{
+			"attribute expression with quote",
+			`<div value={/* hello */} />`,
+			[]TokenType{SelfClosingTagToken},
+		},
+		{
+			"JSX-style comment inside element",
+			`<div {/* hello */} a=b />`,
+			[]TokenType{SelfClosingTagToken},
+		},
 		{
 			"quotes within textContent",
 			`<p>can't</p>`,
@@ -182,8 +197,6 @@ func TestBasic(t *testing.T) {
 			`<Fragment>foo</Fragment>`,
 			[]TokenType{StartTagToken, TextToken, EndTagToken},
 		},
-		// Special Case: this should PANIC! Not sure how to test for a panic
-
 	}
 
 	runTokenTypeTest(t, Basic)
@@ -201,6 +214,11 @@ To fix this, please change
 to use the longhand Fragment syntax:
   <Fragment slot="named">`,
 		},
+		{
+			"block comment in attribute",
+			`<div {// uhh} />`,
+			`Block comments (//) are not allowed inside of expressions`,
+		},
 	}
 	runPanicTest(t, Panics)
 }
@@ -573,6 +591,11 @@ func TestAttributes(t *testing.T) {
 			`<div a="value" b='value' c=value/>`,
 			[]AttributeType{QuotedAttribute, QuotedAttribute, QuotedAttribute},
 		},
+		{
+			"expression with quoted braces",
+			`<div value={ "{" } />`,
+			[]AttributeType{ExpressionAttribute},
+		},
 	}
 
 	runAttributeTypeTest(t, Attributes)