Fix #376

Author: CppCXY

crates/emmylua_code_analysis/src/compilation/test/mod.rs

@@ -18,6 +18,7 @@ mod out_of_order;
 mod overload_field;
 mod overload_test;
 mod pcall_test;
+mod return_unwrap_test;
 mod static_cal_cmp;
 mod syntax_error_test;
 mod tuple_test;

crates/emmylua_code_analysis/src/compilation/test/return_unwrap_test.rs

@@ -0,0 +1,27 @@
+#[cfg(test)]
+mod test {
+    use crate::{LuaType, VirtualWorkspace};
+
+    #[test]
+    fn test_issue_376() {
+        let mut ws = VirtualWorkspace::new();
+
+        ws.def(
+            r#"
+        ---@return any
+        function get() end
+
+        local sub = get()
+
+        if sub and type(sub) == 'table' then
+            -- sub is nil - wrong
+            a = sub
+        end
+        "#,
+        );
+
+        let a_ty = ws.expr_ty("a");
+        let expected = LuaType::Table;
+        assert_eq!(a_ty, expected);
+    }
+}

crates/emmylua_code_analysis/src/semantic/infer/infer_call/mod.rs

@@ -369,7 +369,7 @@ fn unwrapp_return_type(
     call_expr: LuaCallExpr,
 ) -> InferResult {
     match &return_type {
-        LuaType::Table | LuaType::Any | LuaType::Unknown => {
+        LuaType::Table => {
             let id = InFiled {
                 file_id: cache.get_file_id(),
                 value: call_expr.get_range(),