parser: fix parsing of `go` call expression (#8138)

vlib/v/parser/assign.v

@@ -90,41 +90,21 @@ fn (mut p Parser) partial_assign_stmt(left []ast.Expr, left_comments []ast.Comme
 	op := p.tok.kind
 	pos := p.tok.position()
 	p.next()
+	mut comments := []ast.Comment{cap: 2 * left_comments.len + 1}
+	comments << left_comments
+	comments << p.eat_comments()
 	mut right_comments := []ast.Comment{}
 	mut right := []ast.Expr{cap: left.len}
 	if p.tok.kind == .key_go {
-		spos := p.tok.position()
-		p.next()
-		right_comments = p.eat_comments()
-		mut mod := ''
-		mut language := table.Language.v
-		if p.peek_tok.kind == .dot {
-			if p.tok.lit == 'C' {
-				language = table.Language.c
-				p.check_for_impure_v(language, p.tok.position())
-			} else if p.tok.lit == 'JS' {
-				language = table.Language.js
-				p.check_for_impure_v(language, p.tok.position())
-			} else {
-				mod = p.tok.lit
-			}
-			p.next()
-			p.next()
-		}
-		call_expr := p.call_expr(language, mod)
-		allpos := spos.extend(p.tok.position())
+		stmt := p.stmt(false)
+		go_stmt := stmt as ast.GoStmt
 		right << ast.GoExpr{
-			go_stmt: ast.GoStmt{
-				call_expr: call_expr
-				pos: allpos
-			}
-			pos: allpos
+			go_stmt: go_stmt
+			pos: go_stmt.pos
 		}
 	} else {
 		right, right_comments = p.expr_list()
 	}
-	mut comments := []ast.Comment{cap: left_comments.len + right_comments.len}
-	comments << left_comments
 	comments << right_comments
 	end_comments := p.eat_line_end_comments()
 	mut has_cross_var := false

vlib/v/tests/go_wait_3_test.v

@@ -0,0 +1,22 @@
+struct Test {
+	sub SubTest
+}
+
+struct SubTest {
+	test string
+}
+
+fn test_method_go_wait() {
+	a := Test{
+		sub: SubTest{
+			test: 'hi'
+		}
+	}
+	thread := go a.sub.get()
+	r := thread.wait()
+	assert r == 'hi'
+}
+
+fn (t SubTest) get() string {
+	return t.test
+}