checker: handle builtin enum init correctly

vlib/os/os.v

@@ -546,6 +546,10 @@ pub fn temp_dir() string {
 			}
 		}
 	}
+	$if macos {
+		// avoid /var/folders/6j/cmsk8gd90pd.... on macs
+		return '/tmp'
+	}
 	$if android {
 		// TODO test+use '/data/local/tmp' on Android before using cache_dir()
 		if path == '' {

vlib/sqlite/sqlite.v

@@ -92,6 +92,7 @@ pub fn (mut db DB) close() ?bool {
 
 // Only for V ORM
 fn (db DB) init_stmt(query string) &C.sqlite3_stmt {
+	// println('init_stmt("$query")')
 	stmt := &C.sqlite3_stmt(0)
 	C.sqlite3_prepare_v2(db.conn, &char(query.str), query.len, &stmt, 0)
 	return stmt

vlib/sync/channel_1_test.v

@@ -17,3 +17,9 @@ fn test_channel_buffered() {
 	}
 	assert sum == u64(num_iterations) * (num_iterations - 1) / 2
 }
+
+fn test_builtin_enum() {
+	x := ChanState.closed
+	assert x == .closed
+	println(x)
+}

vlib/v/ast/table.v

@@ -523,7 +523,7 @@ pub fn (mut t Table) register_type_symbol(typ TypeSymbol) int {
 			.placeholder {
 				// override placeholder
 				// println('overriding type placeholder `$typ.name`')
-				t.type_symbols[existing_idx] = TypeSymbol{
+				t.type_symbols[existing_idx] = {
 					...typ
 					methods: ex_type.methods
 				}

vlib/v/checker/checker.v

@@ -6455,15 +6455,23 @@ pub fn (mut c Checker) index_expr(mut node ast.IndexExpr) ast.Type {
 // If a short form is used, `expected_type` needs to be an enum
 // with this value.
 pub fn (mut c Checker) enum_val(mut node ast.EnumVal) ast.Type {
-	typ_idx := if node.enum_name == '' {
+	mut typ_idx := if node.enum_name == '' {
 		c.expected_type.idx()
 	} else { //
 		c.table.find_type_idx(node.enum_name)
 	}
 	// println('checker: enum_val: $node.enum_name typeidx=$typ_idx')
 	if typ_idx == 0 {
-		c.error('not an enum (name=$node.enum_name) (type_idx=0)', node.pos)
+		// Handle `builtin` enums like `ChanState`, so that `x := ChanState.closed` works.
-		return ast.void_type
+		// In the checker the name for such enums was set to `main.ChanState` instead of
+		// just `ChanState`.
+		if node.enum_name.starts_with('main.') {
+			typ_idx = c.table.find_type_idx(node.enum_name['.main'.len..])
+			if typ_idx == 0 {
+				c.error('unknown enum `$node.enum_name` (type_idx=0)', node.pos)
+				return ast.void_type
+			}
+		}
 	}
 	mut typ := ast.new_type(typ_idx)
 	if c.pref.translated {

vlib/vweb/vweb.v

@@ -316,7 +316,7 @@ pub fn run<T>(global_app &T, port int) {
 	//}
 	for {
 		// Create a new app object for each connection, copy global data like db connections
-		mut request_app := T{}
+		mut request_app := &T{}
 		$if T is DbInterface {
 			request_app.db = global_app.db
 		} $else {
@@ -619,6 +619,7 @@ pub fn (ctx &Context) ip() string {
 
 // Set s to the form error
 pub fn (mut ctx Context) error(s string) {
+	println('vweb error: $s')
 	ctx.form_error = s
 }