parser: fix anon_fn with array arguments (#9414)

Author: yuyi98

vlib/v/parser/fn.v

@@ -643,7 +643,7 @@ fn (mut p Parser) fn_args() ([]table.Param, bool, bool) {
 	} else {
 		p.tok.lit
 	}
-	types_only := p.tok.kind in [.amp, .ellipsis, .key_fn]
+	types_only := p.tok.kind in [.amp, .ellipsis, .key_fn, .lsbr]
 		|| (p.peek_tok.kind == .comma && p.table.known_type(argname))
 		|| p.peek_tok.kind == .dot || p.peek_tok.kind == .rpar
 	// TODO copy pasta, merge 2 branches

vlib/v/tests/anon_fn_with_array_arguments.v

@@ -0,0 +1,12 @@
+fn fn_arg(f fn ([]int) int) int {
+	return f([1, 2, 3])
+}
+
+fn test_anon_fn_with_array_arguments() {
+	anon := fn (i []int) int {
+		return 0
+	}
+
+	println(fn_arg(anon))
+	assert fn_arg(anon) == 0
+}