hcl/parser: fix broken parsing of: "v=/\n[,"

hcl/parser/parser.go

@@ -331,7 +331,7 @@ func (p *Parser) listType() (*ast.ListType, error) {
 			// get next list item or we are at the end
 			// do a look-ahead for line comment
 			p.scan()
-			if p.lineComment != nil {
+			if p.lineComment != nil && len(l.List) > 0 {
 				lit, ok := l.List[len(l.List)-1].(*ast.LiteralType)
 				if ok {
 					lit.LineComment = p.lineComment

hcl/parser/parser_test.go

@@ -343,9 +343,13 @@ func TestParse_inline(t *testing.T) {
 		{"o{{}}", true},
 		{"t t e d N{{}}", true},
 		{"t t e d{{}}", true},
+		{"N{}N{{}}", true},
+		{"v\nN{{}}", true},
+		{"v=/\n[,", true},
 	}
 
 	for _, tc := range cases {
+		t.Logf("Testing: %q", tc.Value)
 		ast, err := Parse([]byte(tc.Value))
 		if (err != nil) != tc.Err {
 			t.Fatalf("Input: %q\n\nError: %s\n\nAST: %s", tc.Value, err, spew.Sdump(ast))