Merge pull request #413 from xuhuanzy/fix_405

fix #405

Author: CppCXY

crates/emmylua_code_analysis/src/compilation/analyzer/flow/var_analyze/broadcast_up.rs

@@ -1,7 +1,8 @@
 use std::sync::Arc;
 
 use emmylua_parser::{
-    BinaryOperator, LuaAst, LuaAstNode, LuaBinaryExpr, LuaExpr, LuaLiteralToken, UnaryOperator,
+    BinaryOperator, LuaAst, LuaAstNode, LuaBinaryExpr, LuaExpr, LuaForStat, LuaLiteralToken,
+    UnaryOperator,
 };
 use smol_str::SmolStr;
 
@@ -184,6 +185,17 @@ pub fn broadcast_up(
                         );
                     }
                 }
+                UnaryOperator::OpLen => {
+                    if let Some(for_stat) = unary_expr.get_parent::<LuaForStat>() {
+                        broadcast_inside_condition_block(
+                            db,
+                            var_trace,
+                            trace_info.with_type_assertion(TypeAssertion::Narrow(LuaType::Table)),
+                            for_stat.get_block()?,
+                            false,
+                        );
+                    }
+                }
                 _ => {}
             }
         }

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

@@ -560,4 +560,24 @@ end
             "#,
         ));
     }
+
+    #[test]
+    fn test_issue_405() {
+        let mut ws = VirtualWorkspace::new();
+
+        ws.def(
+            r#"
+            ---@type false|fun(...)[]?
+            local calls
+
+            for i = 1, #calls do
+                a = calls
+            end
+        "#,
+        );
+
+        let a = ws.expr_ty("a");
+        let a_expected = ws.ty("fun(...)[]");
+        assert_eq!(a, a_expected);
+    }
 }

crates/emmylua_code_analysis/src/diagnostic/test/need_check_nil_test.rs

@@ -14,4 +14,23 @@ mod test {
         "#
         ));
     }
+
+    #[test]
+    fn test_issue_405() {
+        let mut ws = VirtualWorkspace::new();
+        let mut emmyrc = ws.analysis.emmyrc.as_ref().clone();
+        emmyrc.strict.array_index = false;
+        ws.analysis.update_config(emmyrc.into());
+        assert!(ws.check_code_for(
+            DiagnosticCode::NeedCheckNil,
+            r#"
+                ---@type false|fun(...)[]?
+                local calls
+
+                for i = 1, #calls do
+                    calls[i](...)
+                end
+        "#
+        ));
+    }
 }