From 8d1e6556887403b59e350b6a3798bb78b4cd5de6 Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Tue, 25 Mar 2025 14:08:43 +0800
Subject: [PATCH 01/22] update tpl_pattern_match

---
 .../resources/std/global.lua                  |  2 +-
 .../diagnostic/test/undefined_field_test.rs   | 23 +++++++++
 .../generic/instantiate_type_generic.rs       |  2 +-
 .../src/semantic/generic/tpl_pattern.rs       | 47 ++++++++++++++++++-
 4 files changed, 71 insertions(+), 3 deletions(-)

diff --git a/crates/emmylua_code_analysis/resources/std/global.lua b/crates/emmylua_code_analysis/resources/std/global.lua
index 80cb0c06b..0e414642c 100644
--- a/crates/emmylua_code_analysis/resources/std/global.lua
+++ b/crates/emmylua_code_analysis/resources/std/global.lua
@@ -114,7 +114,7 @@ function getmetatable(object) end
 --- will iterate over the key–value pairs (1,`t[1]`), (2,`t[2]`), ..., up to
 --- the first absent index.
 ---@generic V
----@param t V[] | table<any, V>
+---@param t V[] | table<any, V> | {[any]: V}
 ---@return fun(tbl: any):int, std.NotNull<V>
 function ipairs(t) end
 
diff --git a/crates/emmylua_code_analysis/src/diagnostic/test/undefined_field_test.rs b/crates/emmylua_code_analysis/src/diagnostic/test/undefined_field_test.rs
index 4418f63f5..25600bb55 100644
--- a/crates/emmylua_code_analysis/src/diagnostic/test/undefined_field_test.rs
+++ b/crates/emmylua_code_analysis/src/diagnostic/test/undefined_field_test.rs
@@ -2,6 +2,29 @@
 mod test {
     use crate::{DiagnosticCode, VirtualWorkspace};
 
+    #[test]
+    fn test_1() {
+        let mut ws = VirtualWorkspace::new();
+        assert!(ws.check_code_for(
+            DiagnosticCode::UndefinedField,
+            r#"
+                ---@alias std.NotNull<T> T - ?
+
+                ---@generic V
+                ---@param t {[any]: V}
+                ---@return fun(tbl: any):int, std.NotNull<V>
+                function ipairs(t) end
+
+                ---@type {[integer]: string|table}
+                local a = {}
+
+                for i, extendsName in ipairs(a) do
+                    print(extendsName.a)
+                end 
+            "#
+        ));
+    }
+
     #[test]
     fn test() {
         let mut ws = VirtualWorkspace::new();
diff --git a/crates/emmylua_code_analysis/src/semantic/generic/instantiate_type_generic.rs b/crates/emmylua_code_analysis/src/semantic/generic/instantiate_type_generic.rs
index ec7f17cbc..4e50cbb78 100644
--- a/crates/emmylua_code_analysis/src/semantic/generic/instantiate_type_generic.rs
+++ b/crates/emmylua_code_analysis/src/semantic/generic/instantiate_type_generic.rs
@@ -363,7 +363,7 @@ fn instantiate_alias_call(
             if operands.len() != 2 {
                 return LuaType::Unknown;
             }
-
+            // 如果类型为`Union`且只有一个类型, 则会解开`Union`包装
             return TypeOps::Remove.apply(&operands[0], &operands[1]);
         }
         LuaAliasCallKind::Add => {
diff --git a/crates/emmylua_code_analysis/src/semantic/generic/tpl_pattern.rs b/crates/emmylua_code_analysis/src/semantic/generic/tpl_pattern.rs
index af8b77075..7ec87b53b 100644
--- a/crates/emmylua_code_analysis/src/semantic/generic/tpl_pattern.rs
+++ b/crates/emmylua_code_analysis/src/semantic/generic/tpl_pattern.rs
@@ -1,12 +1,15 @@
 use std::ops::Deref;
 
 use emmylua_parser::LuaSyntaxNode;
+use itertools::Itertools;
 use smol_str::SmolStr;
 
 use crate::{
+    check_type_compact,
     db_index::{DbIndex, LuaGenericType, LuaType},
     semantic::{member::infer_member_map, LuaInferCache},
-    LuaFunctionType, LuaMemberKey, LuaMemberOwner, LuaMultiReturn, LuaTupleType, LuaUnionType,
+    LuaFunctionType, LuaMemberKey, LuaMemberOwner, LuaMultiReturn, LuaObjectType, LuaTupleType,
+    LuaUnionType,
 };
 
 use super::type_substitutor::TypeSubstitutor;
@@ -158,12 +161,50 @@ fn tpl_pattern_match(
         LuaType::Tuple(tuple) => {
             tuple_tpl_pattern_match(db, cache, root, tuple, target, substitutor);
         }
+        LuaType::Object(obj) => {
+            object_tpl_pattern_match(db, cache, root, obj, target, substitutor);
+        }
         _ => {}
     }
 
     Some(())
 }
 
+fn object_tpl_pattern_match(
+    db: &DbIndex,
+    cache: &mut LuaInferCache,
+    root: &LuaSyntaxNode,
+    origin_obj: &LuaObjectType,
+    target: &LuaType,
+    substitutor: &mut TypeSubstitutor,
+) -> Option<()> {
+    match target {
+        LuaType::Object(target_object) => {
+            // 先匹配 fields
+            for (k, v) in origin_obj.get_fields().iter().sorted_by_key(|(k, _)| *k) {
+                let target_value = target_object.get_fields().get(k);
+                if let Some(target_value) = target_value {
+                    tpl_pattern_match(db, cache, root, v, target_value, substitutor);
+                }
+            }
+            // 再匹配索引访问
+            let target_index_access = target_object.get_index_access();
+            for (origin_key, v) in origin_obj.get_index_access() {
+                // 先匹配 key 类型进行转换
+                let target_access = target_index_access
+                    .iter()
+                    .find(|(target_key, _)| check_type_compact(db, origin_key, target_key).is_ok());
+                if let Some(target_access) = target_access {
+                    tpl_pattern_match(db, cache, root, origin_key, &target_access.0, substitutor);
+                    tpl_pattern_match(db, cache, root, v, &target_access.1, substitutor);
+                }
+            }
+        }
+        _ => {}
+    }
+    Some(())
+}
+
 fn array_tpl_pattern_match(
     db: &DbIndex,
     cache: &mut LuaInferCache,
@@ -306,6 +347,10 @@ fn table_generic_tpl_pattern_match(
                 };
                 values.push(v.clone());
             }
+            for (k, v) in obj.get_index_access() {
+                keys.push(k.clone());
+                values.push(v.clone());
+            }
 
             let key_type = LuaType::Union(LuaUnionType::new(keys).into());
             let value_type = LuaType::Union(LuaUnionType::new(values).into());

From 8562f4100a2e7bfa44fae70586a4ac0655e24f99 Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Tue, 25 Mar 2025 15:11:16 +0800
Subject: [PATCH 02/22] =?UTF-8?q?=E5=BD=93=E5=89=8D=E6=89=93=E5=BC=80?=
 =?UTF-8?q?=E7=9A=84=E6=96=87=E4=BB=B6=E5=88=97=E8=A1=A8=E4=B8=8D=E8=A7=A6?=
 =?UTF-8?q?=E5=8F=91=20watched=5Ffiles?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../emmylua_ls/src/context/workspace_manager.rs   |  4 ++++
 .../text_document/text_document_handler.rs        | 13 +++++++++++--
 .../text_document/watched_file_handler.rs         | 15 +++++++++------
 3 files changed, 24 insertions(+), 8 deletions(-)

diff --git a/crates/emmylua_ls/src/context/workspace_manager.rs b/crates/emmylua_ls/src/context/workspace_manager.rs
index 8317a6fa6..1887b7a4c 100644
--- a/crates/emmylua_ls/src/context/workspace_manager.rs
+++ b/crates/emmylua_ls/src/context/workspace_manager.rs
@@ -1,3 +1,4 @@
+use std::collections::HashSet;
 use std::{path::PathBuf, sync::Arc, time::Duration};
 
 use super::{ClientProxy, FileDiagnostic, StatusBar};
@@ -5,6 +6,7 @@ use crate::handlers::{init_analysis, ClientConfig};
 use emmylua_code_analysis::update_code_style;
 use emmylua_code_analysis::{load_configs, EmmyLuaAnalysis, Emmyrc};
 use log::{debug, info};
+use lsp_types::Uri;
 use tokio::sync::{Mutex, RwLock};
 use tokio_util::sync::CancellationToken;
 
@@ -17,6 +19,7 @@ pub struct WorkspaceManager {
     pub client_config: ClientConfig,
     pub workspace_folders: Vec<PathBuf>,
     pub watcher: Option<notify::RecommendedWatcher>,
+    pub current_open_files: HashSet<Uri>,
 }
 
 impl WorkspaceManager {
@@ -35,6 +38,7 @@ impl WorkspaceManager {
             update_token: Arc::new(Mutex::new(None)),
             file_diagnostic,
             watcher: None,
+            current_open_files: HashSet::new(),
         }
     }
 
diff --git a/crates/emmylua_ls/src/handlers/text_document/text_document_handler.rs b/crates/emmylua_ls/src/handlers/text_document/text_document_handler.rs
index e89cd5146..4aeffc773 100644
--- a/crates/emmylua_ls/src/handlers/text_document/text_document_handler.rs
+++ b/crates/emmylua_ls/src/handlers/text_document/text_document_handler.rs
@@ -25,6 +25,10 @@ pub async fn on_did_open_text_document(
             .await;
     }
 
+    let mut workspace = context.workspace_manager.write().await;
+    workspace.current_open_files.insert(uri);
+    drop(workspace);
+
     Some(())
 }
 
@@ -77,8 +81,13 @@ pub async fn on_did_change_text_document(
 }
 
 pub async fn on_did_close_document(
-    _: ServerContextSnapshot,
-    _: DidCloseTextDocumentParams,
+    context: ServerContextSnapshot,
+    params: DidCloseTextDocumentParams,
 ) -> Option<()> {
+    let mut workspace = context.workspace_manager.write().await;
+    workspace
+        .current_open_files
+        .remove(&params.text_document.uri);
+    drop(workspace);
     Some(())
 }
diff --git a/crates/emmylua_ls/src/handlers/text_document/watched_file_handler.rs b/crates/emmylua_ls/src/handlers/text_document/watched_file_handler.rs
index 5e812abe2..ee9393ecd 100644
--- a/crates/emmylua_ls/src/handlers/text_document/watched_file_handler.rs
+++ b/crates/emmylua_ls/src/handlers/text_document/watched_file_handler.rs
@@ -7,6 +7,7 @@ pub async fn on_did_change_watched_files(
     context: ServerContextSnapshot,
     params: DidChangeWatchedFilesParams,
 ) -> Option<()> {
+    let workspace = context.workspace_manager.read().await;
     let mut analysis = context.analysis.write().await;
     let emmyrc = analysis.get_emmyrc();
     let encoding = &emmyrc.workspace.encoding;
@@ -17,12 +18,14 @@ pub async fn on_did_change_watched_files(
         let file_type = get_file_type(&file_event.uri);
         match file_type {
             Some(WatchedFileType::Lua) => {
-                collect_lua_files(
-                    &mut watched_lua_files,
-                    file_event.uri,
-                    file_event.typ,
-                    encoding,
-                );
+                if !workspace.current_open_files.contains(&file_event.uri) {
+                    collect_lua_files(
+                        &mut watched_lua_files,
+                        file_event.uri,
+                        file_event.typ,
+                        encoding,
+                    );
+                }
             }
             Some(WatchedFileType::Editorconfig) => {
                 if file_event.typ == FileChangeType::DELETED {

From ceab5e0f56f06baa0a5eab85457cb22d5c11b8d4 Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Tue, 25 Mar 2025 15:31:34 +0800
Subject: [PATCH 03/22] diagnostic: fix RedundantParameter

---
 .../diagnostic/checker/check_param_count.rs   | 36 ++++++++++++++++---
 .../test/redundant_parameter_test.rs          | 16 +++++++++
 2 files changed, 47 insertions(+), 5 deletions(-)

diff --git a/crates/emmylua_code_analysis/src/diagnostic/checker/check_param_count.rs b/crates/emmylua_code_analysis/src/diagnostic/checker/check_param_count.rs
index 734ff27b7..906fd750b 100644
--- a/crates/emmylua_code_analysis/src/diagnostic/checker/check_param_count.rs
+++ b/crates/emmylua_code_analysis/src/diagnostic/checker/check_param_count.rs
@@ -45,14 +45,18 @@ fn check_closure_expr(
             semantic_model.get_file_id(),
             &closure_expr,
         ))?;
-    let source_params_len = match source_typ {
-        LuaType::DocFunction(func_type) => func_type.get_params().len(),
+    let source_params_len = match &source_typ {
+        LuaType::DocFunction(func_type) => {
+            let params = func_type.get_params();
+            get_params_len(params)
+        }
         LuaType::Signature(signature_id) => {
             let signature = context.db.get_signature_index().get(&signature_id)?;
-            signature.get_type_params().len()
+            let params = signature.get_type_params();
+            get_params_len(&params)
         }
         _ => return Some(()),
-    };
+    }?;
 
     // 只检查右值参数多于左值参数的情况, 右值参数少于左值参数的情况是能够接受的
     if source_params_len > right_value.params.len() {
@@ -166,7 +170,14 @@ fn check_call_expr(
     // Check for redundant parameters
     else if call_args_count > params.len() {
         // 参数定义中最后一个参数是 `...`
-        if params.last().map_or(false, |(name, _)| name == "...") {
+        if params.last().map_or(false, |(name, typ)| {
+            name == "..."
+                || if let Some(typ) = typ {
+                    typ.is_variadic()
+                } else {
+                    false
+                }
+        }) {
             return Some(());
         }
 
@@ -198,3 +209,18 @@ fn check_call_expr(
 
     Some(())
 }
+
+fn get_params_len(params: &[(String, Option<LuaType>)]) -> Option<usize> {
+    if let Some((name, typ)) = params.last() {
+        // 如果最后一个参数是可变参数, 则直接返回, 不需要检查
+        if name == "..." {
+            return None;
+        }
+        if let Some(typ) = typ {
+            if typ.is_variadic() {
+                return None;
+            }
+        }
+    }
+    Some(params.len())
+}
diff --git a/crates/emmylua_code_analysis/src/diagnostic/test/redundant_parameter_test.rs b/crates/emmylua_code_analysis/src/diagnostic/test/redundant_parameter_test.rs
index 2c25872d7..7f507d422 100644
--- a/crates/emmylua_code_analysis/src/diagnostic/test/redundant_parameter_test.rs
+++ b/crates/emmylua_code_analysis/src/diagnostic/test/redundant_parameter_test.rs
@@ -49,6 +49,22 @@ mod test {
         ));
     }
 
+    #[test]
+    fn test_1() {
+        let mut ws = VirtualWorkspace::new();
+
+        assert!(ws.check_code_for(
+            DiagnosticCode::RedundantParameter,
+            r#"
+                ---@type fun(...)[]
+                local a = {}
+
+                a[1] = function(ccc, ...)
+                end
+        "#
+        ));
+    }
+
     #[test]
     fn test_dots() {
         let mut ws = VirtualWorkspace::new();

From a9b6fc8e15b759b7dbff9a12cc7acb6f1489656f Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Tue, 25 Mar 2025 16:36:32 +0800
Subject: [PATCH 04/22] diagnostic: update UndefinedField

---
 .../src/diagnostic/checker/check_field.rs     | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/crates/emmylua_code_analysis/src/diagnostic/checker/check_field.rs b/crates/emmylua_code_analysis/src/diagnostic/checker/check_field.rs
index 3ff93a133..4e9558233 100644
--- a/crates/emmylua_code_analysis/src/diagnostic/checker/check_field.rs
+++ b/crates/emmylua_code_analysis/src/diagnostic/checker/check_field.rs
@@ -92,3 +92,22 @@ fn check_index_expr(
 
     Some(())
 }
+
+#[allow(dead_code)]
+fn is_valid_prefix_type(typ: &LuaType) -> bool {
+    let mut current_typ = typ;
+    loop {
+        match current_typ {
+            LuaType::Any
+            | LuaType::Unknown
+            | LuaType::Table
+            | LuaType::TplRef(_)
+            | LuaType::StrTplRef(_)
+            | LuaType::TableConst(_) => return false,
+            LuaType::Instance(instance_typ) => {
+                current_typ = instance_typ.get_base();
+            }
+            _ => return true,
+        }
+    }
+}

From b17d16c898efb53ea8c2eb3d716cf0698eca6a04 Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Tue, 25 Mar 2025 18:39:21 +0800
Subject: [PATCH 05/22] diagnostic: update signature match algorithm

---
 .../diagnostic/test/missing_parameter_test.rs |  19 +++
 .../src/semantic/overload_resolve/mod.rs      | 109 +++++++++++++++---
 2 files changed, 114 insertions(+), 14 deletions(-)

diff --git a/crates/emmylua_code_analysis/src/diagnostic/test/missing_parameter_test.rs b/crates/emmylua_code_analysis/src/diagnostic/test/missing_parameter_test.rs
index 7a359949f..d2bba5834 100644
--- a/crates/emmylua_code_analysis/src/diagnostic/test/missing_parameter_test.rs
+++ b/crates/emmylua_code_analysis/src/diagnostic/test/missing_parameter_test.rs
@@ -2,6 +2,25 @@
 mod test {
     use crate::{DiagnosticCode, VirtualWorkspace};
 
+    #[test]
+    fn test_issue_276() {
+        let mut ws = VirtualWorkspace::new();
+
+        assert!(ws.check_code_for(
+            DiagnosticCode::MissingParameter,
+            r#"
+                --- @param a string
+                --- @param b? string
+                --- @param c? string
+                --- @return string
+                --- @overload fun(a: string, b: string): number
+                local function myfun2(a, b, c) end
+
+                local a = myfun2('string')
+        "#
+        ));
+    }
+
     #[test]
     fn test_issue_249() {
         let mut ws = VirtualWorkspace::new();
diff --git a/crates/emmylua_code_analysis/src/semantic/overload_resolve/mod.rs b/crates/emmylua_code_analysis/src/semantic/overload_resolve/mod.rs
index 89da7399d..6e82589b4 100644
--- a/crates/emmylua_code_analysis/src/semantic/overload_resolve/mod.rs
+++ b/crates/emmylua_code_analysis/src/semantic/overload_resolve/mod.rs
@@ -1,4 +1,4 @@
-use std::{cmp::Ordering, sync::Arc};
+use std::sync::Arc;
 
 use emmylua_parser::LuaCallExpr;
 
@@ -69,7 +69,7 @@ fn resolve_signature_by_args(
 ) -> InferCallFuncResult {
     let arg_count = arg_count.unwrap_or(0);
     let mut opt_funcs = Vec::with_capacity(overloads.len());
-    // 函数本身签名在尾部
+
     for func in overloads {
         let params = func.get_params();
         if params.len() < arg_count {
@@ -81,36 +81,117 @@ fn resolve_signature_by_args(
         } else {
             0
         };
-        let mut match_count = 0;
+        let mut total_weight = 0; // 总权重
         let expr_len = expr_types.len();
 
+        // 检查每个参数的匹配情况
         for (i, param) in params.iter().enumerate() {
             if i == 0 && jump_param > 0 {
-                continue;
+                continue; // 处理冒号调用时的偏移
             }
+            let param_type = param.1.as_ref().unwrap_or(&LuaType::Any);
             let expr_idx = i - jump_param;
+
             if expr_idx >= expr_len {
-                break;
+                // 没有传入参数, 但参数是可空类型
+                if param_type.is_nullable() {
+                    total_weight += 1;
+                }
+                continue;
             }
 
-            let param_type = param.1.as_ref().unwrap_or(&LuaType::Any);
             let expr_type = &expr_types[expr_idx];
             if *param_type == LuaType::Any || check_type_compact(db, param_type, expr_type).is_ok()
             {
-                match_count += 1;
+                total_weight += 100; // 类型完全匹配
             }
         }
-        opt_funcs.push((func, params.len(), match_count));
+        // 如果参数数量完全匹配, 则认为其权重更高
+        if total_weight > 0 && params.len() == expr_types.len() {
+            total_weight += 50000;
+        }
+
+        opt_funcs.push((func, total_weight));
     }
-    // 优先降序匹配`match_count`使匹配度最高的函数排在前面, 其次升序匹配`params.len()`使参数个数最少的函数排在前面.
-    opt_funcs.sort_by(|a, b| match b.2.cmp(&a.2) {
-        Ordering::Equal => a.1.cmp(&b.1),
-        other => other,
-    });
 
+    // 按权重降序排序
+    opt_funcs.sort_by(|a, b| b.1.cmp(&a.1));
+
+    // 返回权重最高的签名，若无则取最后一个重载作为默认
     opt_funcs
         .first()
-        .map(|(func, _, _)| Arc::clone(func))
+        .filter(|(_, weight)| *weight > i32::MIN) // 确保不是无效签名
+        .map(|(func, _)| Arc::clone(func))
         .or_else(|| overloads.last().cloned())
         .ok_or(InferFailReason::None)
 }
+
+// fn resolve_signature_by_args(
+//     db: &DbIndex,
+//     overloads: &[Arc<LuaFunctionType>],
+//     expr_types: &[LuaType],
+//     is_colon_call: bool,
+//     arg_count: Option<usize>,
+// ) -> Option<Arc<LuaFunctionType>> {
+//     let arg_count = arg_count.unwrap_or(0);
+//     let mut opt_funcs = Vec::with_capacity(overloads.len());
+//     // 函数本身签名在尾部
+//     for func in overloads {
+//         let params = func.get_params();
+//         if params.len() < arg_count {
+//             continue;
+//         }
+
+//         let jump_param = if is_colon_call && !func.is_colon_define() {
+//             1
+//         } else {
+//             0
+//         };
+//         let mut match_count = 0;
+//         let mut skip_param = 0;
+//         let expr_len = expr_types.len();
+
+//         for (i, param) in params.iter().enumerate() {
+//             if i == 0 && jump_param > 0 {
+//                 continue;
+//             }
+//             let param_type = param.1.as_ref().unwrap_or(&LuaType::Any);
+//             let expr_idx = i - jump_param;
+//             if expr_idx >= expr_len {
+//                 if param_type.is_nullable() {
+//                     skip_param += 1;
+//                 }
+//                 continue;
+//             }
+
+//             let expr_type = &expr_types[expr_idx];
+//             if *param_type == LuaType::Any || check_type_compact(db, param_type, expr_type).is_ok()
+//             {
+//                 match_count += 1;
+//             }
+//         }
+//         opt_funcs.push((func, params.len(), match_count, skip_param));
+//     }
+
+//     opt_funcs.sort_by(|a, b| {
+//         match b.2.cmp(&a.2) {
+//             // 比较 match_count 降序
+//             Ordering::Equal => {
+//                 // 计算有效参数个数
+//                 let a_effective_params = a.1 - a.3; // params.len() - skip_param
+//                 let b_effective_params = b.1 - b.3;
+//                 // 升序使有效参数个数最少的函数排在前面
+//                 match a_effective_params.cmp(&b_effective_params) {
+//                     Ordering::Equal => a.1.cmp(&b.1), // 升序使总参数个数最少的函数排在前面
+//                     other => other,
+//                 }
+//             }
+//             other => other,
+//         }
+//     });
+
+//     opt_funcs
+//         .first()
+//         .map(|(func, _, _, _)| Arc::clone(func))
+//         .or_else(|| overloads.last().cloned())
+// }

From 25f63357ce37e3af7b8150bd3e241b9ac55bdf2f Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Tue, 25 Mar 2025 22:45:56 +0800
Subject: [PATCH 06/22] table field -> FileDefine

---
 .../src/compilation/analyzer/decl/exprs.rs                    | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/crates/emmylua_code_analysis/src/compilation/analyzer/decl/exprs.rs b/crates/emmylua_code_analysis/src/compilation/analyzer/decl/exprs.rs
index fbe9c4133..1b32e110b 100644
--- a/crates/emmylua_code_analysis/src/compilation/analyzer/decl/exprs.rs
+++ b/crates/emmylua_code_analysis/src/compilation/analyzer/decl/exprs.rs
@@ -202,9 +202,9 @@ pub fn analyze_table_expr(analyzer: &mut DeclAnalyzer, expr: LuaTableExpr) -> Op
                 );
 
                 let decl_feature = if analyzer.is_meta {
-                    LuaMemberFeature::MetaFieldDecl
+                    LuaMemberFeature::MetaDefine
                 } else {
-                    LuaMemberFeature::FileFieldDecl
+                    LuaMemberFeature::FileDefine
                 };
 
                 let member_id = LuaMemberId::new(field.get_syntax_id(), file_id);

From c8410481850080d928d1a9aa1758ebe8d458d0cd Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Wed, 26 Mar 2025 00:29:20 +0800
Subject: [PATCH 07/22] flow fix elseif

---
 .../compilation/analyzer/flow/var_analyze.rs  | 39 ++++++++++++++-----
 .../src/compilation/test/flow.rs              | 22 +++++++++++
 2 files changed, 51 insertions(+), 10 deletions(-)

diff --git a/crates/emmylua_code_analysis/src/compilation/analyzer/flow/var_analyze.rs b/crates/emmylua_code_analysis/src/compilation/analyzer/flow/var_analyze.rs
index 8ca50194c..1c3f4f6cb 100644
--- a/crates/emmylua_code_analysis/src/compilation/analyzer/flow/var_analyze.rs
+++ b/crates/emmylua_code_analysis/src/compilation/analyzer/flow/var_analyze.rs
@@ -132,16 +132,35 @@ fn broadcast_up(
             if let Some(ne_type_assert) = type_assert.get_negation() {
                 if let Some(else_stat) = if_stat.get_else_clause() {
                     let block_range = else_stat.get_range();
-                    flow_chain.add_type_assert(path, ne_type_assert, block_range, actual_range);
-                } else if is_block_has_return(if_stat.get_block()?).unwrap_or(false) {
+                    flow_chain.add_type_assert(
+                        path,
+                        ne_type_assert.clone(),
+                        block_range,
+                        actual_range,
+                    );
+                } else if is_block_has_return(if_stat.get_block()).unwrap_or(false) {
                     let parent_block = if_stat.get_parent::<LuaBlock>()?;
                     let parent_range = parent_block.get_range();
                     let if_range = if_stat.get_range();
                     if if_range.end() < parent_range.end() {
                         let range = TextRange::new(if_range.end(), parent_range.end());
-                        flow_chain.add_type_assert(path, ne_type_assert, range, actual_range);
+                        flow_chain.add_type_assert(
+                            path,
+                            ne_type_assert.clone(),
+                            range,
+                            actual_range,
+                        );
                     }
                 }
+                for else_if_clause in if_stat.get_else_if_clause_list() {
+                    let block_range = else_if_clause.get_range();
+                    flow_chain.add_type_assert(
+                        path,
+                        ne_type_assert.clone(),
+                        block_range,
+                        actual_range,
+                    );
+                }
             }
         }
         LuaAst::LuaWhileStat(while_stat) => {
@@ -445,10 +464,12 @@ fn infer_lua_type_assert(
     Some(())
 }
 
-fn is_block_has_return(block: LuaBlock) -> Option<bool> {
-    for stat in block.get_stats() {
-        if is_stat_change_flow(stat.clone()).unwrap_or(false) {
-            return Some(true);
+fn is_block_has_return(block: Option<LuaBlock>) -> Option<bool> {
+    if let Some(block) = block {
+        for stat in block.get_stats() {
+            if is_stat_change_flow(stat.clone()).unwrap_or(false) {
+                return Some(true);
+            }
         }
     }
 
@@ -469,9 +490,7 @@ fn is_stat_change_flow(stat: LuaStat) -> Option<bool> {
             Some(false)
         }
         LuaStat::ReturnStat(_) => Some(true),
-        LuaStat::DoStat(do_stat) => {
-            Some(is_block_has_return(do_stat.get_block()?).unwrap_or(false))
-        }
+        LuaStat::DoStat(do_stat) => Some(is_block_has_return(do_stat.get_block()).unwrap_or(false)),
         _ => Some(false),
     }
 }
diff --git a/crates/emmylua_code_analysis/src/compilation/test/flow.rs b/crates/emmylua_code_analysis/src/compilation/test/flow.rs
index e2e7a1c7a..8c359d72f 100644
--- a/crates/emmylua_code_analysis/src/compilation/test/flow.rs
+++ b/crates/emmylua_code_analysis/src/compilation/test/flow.rs
@@ -278,4 +278,26 @@ print(a.field)
         "#
         ));
     }
+
+    #[test]
+    fn test_elseif() {
+        let mut ws = VirtualWorkspace::new();
+
+        assert!(ws.check_code_for(
+            DiagnosticCode::NeedCheckNil,
+            r#"
+---@class D11
+---@field public a string
+
+---@type D11|nil
+local a
+
+if not a then
+elseif a.a then
+    print(a.a)
+end
+
+        "#
+        ));
+    }
 }

From 9d472dd4e051db52a297f7e134ad8d6cee693030 Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Wed, 26 Mar 2025 02:22:16 +0800
Subject: [PATCH 08/22] optimize infer_union

---
 .../test/return_type_mismatch_test.rs         | 18 ++++++++++
 .../src/semantic/infer/infer_binary.rs        | 36 ++++++++++++++-----
 2 files changed, 46 insertions(+), 8 deletions(-)

diff --git a/crates/emmylua_code_analysis/src/diagnostic/test/return_type_mismatch_test.rs b/crates/emmylua_code_analysis/src/diagnostic/test/return_type_mismatch_test.rs
index 2b7dc708e..753f55975 100644
--- a/crates/emmylua_code_analysis/src/diagnostic/test/return_type_mismatch_test.rs
+++ b/crates/emmylua_code_analysis/src/diagnostic/test/return_type_mismatch_test.rs
@@ -225,4 +225,22 @@ mod tests {
         "#
         ));
     }
+
+    #[test]
+    fn test_1() {
+        let mut ws = VirtualWorkspace::new();
+
+        assert!(ws.check_code_for(
+            DiagnosticCode::ReturnTypeMismatch,
+            r#"
+            ---@return string?
+            local function a()
+                ---@type int?
+                local ccc
+                return ccc and a() or nil
+            end
+
+            "#
+        ));
+    }
 }
diff --git a/crates/emmylua_code_analysis/src/semantic/infer/infer_binary.rs b/crates/emmylua_code_analysis/src/semantic/infer/infer_binary.rs
index e2b735235..b0c574a2b 100644
--- a/crates/emmylua_code_analysis/src/semantic/infer/infer_binary.rs
+++ b/crates/emmylua_code_analysis/src/semantic/infer/infer_binary.rs
@@ -1,3 +1,5 @@
+use std::collections::HashSet;
+
 use emmylua_parser::{BinaryOperator, LuaBinaryExpr};
 use smol_str::SmolStr;
 
@@ -59,17 +61,35 @@ fn infer_binary_expr_type(
 }
 
 fn infer_union(db: &DbIndex, u: &LuaUnionType, right: &LuaType, op: BinaryOperator) -> InferResult {
-    let mut union_types = vec![];
+    let mut unique_union_types = HashSet::new();
+
     for ty in u.get_types() {
-        let ty = infer_binary_expr_type(db, ty.clone(), right.clone(), op)?;
-        union_types.push(ty);
+        let inferred_ty = infer_binary_expr_type(db, ty.clone(), right.clone(), op)?;
+        flatten_and_insert(inferred_ty, &mut unique_union_types);
     }
-    union_types.dedup();
 
-    match union_types.len() {
-        0 => Ok(LuaType::Unknown),
-        1 => Ok(union_types[0].clone()),
-        _ => Ok(LuaType::Union(LuaUnionType::new(union_types).into())),
+    match unique_union_types.len() {
+        0 => Some(LuaType::Unknown),
+        1 => Some(unique_union_types.into_iter().next().unwrap()),
+        _ => Some(LuaType::Union(
+            LuaUnionType::new(unique_union_types.into_iter().collect()).into(),
+        )),
+    }
+}
+
+fn flatten_and_insert(ty: LuaType, unique_union_types: &mut HashSet<LuaType>) {
+    let mut stack = vec![ty];
+    while let Some(current_ty) = stack.pop() {
+        match current_ty {
+            LuaType::Union(u) => {
+                for inner_ty in u.get_types() {
+                    stack.push(inner_ty.clone());
+                }
+            }
+            _ => {
+                unique_union_types.insert(current_ty);
+            }
+        }
     }
 }
 

From 040fb348abe15885ac09946239164db3b9ebb512 Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Wed, 26 Mar 2025 02:38:59 +0800
Subject: [PATCH 09/22] update type_check

---
 .../test/return_type_mismatch_test.rs         | 28 +++++++++++++++----
 .../src/semantic/type_check/complex_type.rs   | 18 ++++++++++++
 2 files changed, 40 insertions(+), 6 deletions(-)

diff --git a/crates/emmylua_code_analysis/src/diagnostic/test/return_type_mismatch_test.rs b/crates/emmylua_code_analysis/src/diagnostic/test/return_type_mismatch_test.rs
index 753f55975..18bf2ed90 100644
--- a/crates/emmylua_code_analysis/src/diagnostic/test/return_type_mismatch_test.rs
+++ b/crates/emmylua_code_analysis/src/diagnostic/test/return_type_mismatch_test.rs
@@ -233,13 +233,29 @@ mod tests {
         assert!(ws.check_code_for(
             DiagnosticCode::ReturnTypeMismatch,
             r#"
-            ---@return string?
-            local function a()
-                ---@type int?
-                local ccc
-                return ccc and a() or nil
-            end
+                ---@return string?
+                local function a()
+                    ---@type int?
+                    local ccc
+                    return ccc and a() or nil
+                end
+            "#
+        ));
+    }
+
+    #[test]
+    fn test_2() {
+        let mut ws = VirtualWorkspace::new();
 
+        assert!(ws.check_code_for(
+            DiagnosticCode::ReturnTypeMismatch,
+            r#"
+                ---@return any[]
+                local function a()
+                    ---@type table|table<any, any>
+                    local ccc
+                    return ccc
+                end
             "#
         ));
     }
diff --git a/crates/emmylua_code_analysis/src/semantic/type_check/complex_type.rs b/crates/emmylua_code_analysis/src/semantic/type_check/complex_type.rs
index 4b2b308e7..2291758e2 100644
--- a/crates/emmylua_code_analysis/src/semantic/type_check/complex_type.rs
+++ b/crates/emmylua_code_analysis/src/semantic/type_check/complex_type.rs
@@ -62,6 +62,24 @@ pub fn check_complex_type_compact(
                 );
             }
             LuaType::Table => return Ok(()),
+            LuaType::TableGeneric(compact_types) => {
+                if compact_types.len() == 2 {
+                    for typ in compact_types.iter() {
+                        if check_general_type_compact(
+                            db,
+                            source_base,
+                            typ,
+                            check_guard.next_level()?,
+                        )
+                        .is_err()
+                        {
+                            return Err(TypeCheckFailReason::TypeNotMatch);
+                        }
+                    }
+
+                    return Ok(());
+                }
+            }
             _ => {}
         },
         LuaType::Tuple(tuple) => {

From 46f15c281839521c117960d63c1513910a9ef3bb Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Wed, 26 Mar 2025 02:45:10 +0800
Subject: [PATCH 10/22] fix test

---
 .../src/semantic/infer/infer_binary.rs             | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/crates/emmylua_code_analysis/src/semantic/infer/infer_binary.rs b/crates/emmylua_code_analysis/src/semantic/infer/infer_binary.rs
index b0c574a2b..6585fda0c 100644
--- a/crates/emmylua_code_analysis/src/semantic/infer/infer_binary.rs
+++ b/crates/emmylua_code_analysis/src/semantic/infer/infer_binary.rs
@@ -1,5 +1,3 @@
-use std::collections::HashSet;
-
 use emmylua_parser::{BinaryOperator, LuaBinaryExpr};
 use smol_str::SmolStr;
 
@@ -61,7 +59,7 @@ fn infer_binary_expr_type(
 }
 
 fn infer_union(db: &DbIndex, u: &LuaUnionType, right: &LuaType, op: BinaryOperator) -> InferResult {
-    let mut unique_union_types = HashSet::new();
+    let mut unique_union_types = Vec::new();
 
     for ty in u.get_types() {
         let inferred_ty = infer_binary_expr_type(db, ty.clone(), right.clone(), op)?;
@@ -71,13 +69,11 @@ fn infer_union(db: &DbIndex, u: &LuaUnionType, right: &LuaType, op: BinaryOperat
     match unique_union_types.len() {
         0 => Some(LuaType::Unknown),
         1 => Some(unique_union_types.into_iter().next().unwrap()),
-        _ => Some(LuaType::Union(
-            LuaUnionType::new(unique_union_types.into_iter().collect()).into(),
-        )),
+        _ => Some(LuaType::Union(LuaUnionType::new(unique_union_types).into())),
     }
 }
 
-fn flatten_and_insert(ty: LuaType, unique_union_types: &mut HashSet<LuaType>) {
+fn flatten_and_insert(ty: LuaType, unique_union_types: &mut Vec<LuaType>) {
     let mut stack = vec![ty];
     while let Some(current_ty) = stack.pop() {
         match current_ty {
@@ -87,7 +83,9 @@ fn flatten_and_insert(ty: LuaType, unique_union_types: &mut HashSet<LuaType>) {
                 }
             }
             _ => {
-                unique_union_types.insert(current_ty);
+                if !unique_union_types.contains(&current_ty) {
+                    unique_union_types.push(current_ty);
+                }
             }
         }
     }

From 4a7f91d8e4132448f7e9feb399bf4aab75e5bfa3 Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Wed, 26 Mar 2025 11:55:36 +0800
Subject: [PATCH 11/22] std update

---
 .../resources/std/global.lua                  |  3 +--
 .../resources/std/string.lua                  | 22 ++++++++++---------
 .../resources/std/table.lua                   |  2 +-
 .../resources/std/utf8.lua                    | 14 +++++++-----
 4 files changed, 22 insertions(+), 19 deletions(-)

diff --git a/crates/emmylua_code_analysis/resources/std/global.lua b/crates/emmylua_code_analysis/resources/std/global.lua
index 0e414642c..462add43d 100644
--- a/crates/emmylua_code_analysis/resources/std/global.lua
+++ b/crates/emmylua_code_analysis/resources/std/global.lua
@@ -87,8 +87,7 @@ function dofile(filename) end
 --- `error` function was called. Level 2 points the error to where the function
 --- that called `error` was called; and so on. Passing a level 0 avoids the
 --- addition of error position information to the message.
----@overload fun(message:string)
----@param message string
+---@param message any
 ---@param level? integer
 function error(message, level) end
 
diff --git a/crates/emmylua_code_analysis/resources/std/string.lua b/crates/emmylua_code_analysis/resources/std/string.lua
index b16ae06d9..0e3d8b1a7 100644
--- a/crates/emmylua_code_analysis/resources/std/string.lua
+++ b/crates/emmylua_code_analysis/resources/std/string.lua
@@ -75,12 +75,14 @@ function string.dump(func, strip) end
 ---
 --- If the pattern has captures, then in a successful match the captured values
 --- are also returned, after the two indices.
----@overload fun(s:string, pattern:string):integer, integer, string...
----@param s string
----@param pattern string
----@param init? integer
----@param plain? boolean
----@return integer, integer, string...
+---@param s       string|number
+---@param pattern string|number
+---@param init?   integer
+---@param plain?  boolean
+---@return integer|nil start
+---@return integer|nil end
+---@return any|nil ... captured
+---@nodiscard
 function string.find(s, pattern, init, plain) end
 
 ---
@@ -276,11 +278,11 @@ function string.reverse(s) end
 --- corrected to 1. If `j` is greater than the string length, it is corrected to
 --- that length. If, after these corrections, `i` is greater than `j`, the
 --- function returns the empty string.
----@overload fun(s:string, i:integer):string
----@param s string
----@param i integer
----@param j integer
+---@param s  string|number
+---@param i  integer
+---@param j? integer
 ---@return string
+---@nodiscard
 function string.sub(s, i, j) end
 
 ---@version >5.3
diff --git a/crates/emmylua_code_analysis/resources/std/table.lua b/crates/emmylua_code_analysis/resources/std/table.lua
index f3567178b..10969fa7e 100644
--- a/crates/emmylua_code_analysis/resources/std/table.lua
+++ b/crates/emmylua_code_analysis/resources/std/table.lua
@@ -109,9 +109,9 @@ function table.sort(list, comp) end
 --- return `list[i]`, `list[i+1]`, `···`, `list[j]`
 --- By default, i is 1 and j is #list.
 ---@generic T
+---@param list [T...] | table<any, T>
 ---@param i? integer
 ---@param j? integer
----@param list [T...]
 ---@return T...
 function table.unpack(list, i, j) end
 
diff --git a/crates/emmylua_code_analysis/resources/std/utf8.lua b/crates/emmylua_code_analysis/resources/std/utf8.lua
index d55a4f524..83f620150 100644
--- a/crates/emmylua_code_analysis/resources/std/utf8.lua
+++ b/crates/emmylua_code_analysis/resources/std/utf8.lua
@@ -60,12 +60,14 @@ function utf8.codepoint(s, i, j) end
 --- positions `i` and `j` (both inclusive). The default for `i` is 1 and for
 --- `j` is -1. If it finds any invalid byte sequence, returns a false value
 --- plus the position of the first invalid byte.
----@overload fun(s:string):number
----@param s string
----@param i? number
----@param j? number
----@return number
-function utf8.len(s, i, j) end
+---@param s    string
+---@param i?   integer
+---@param j?   integer
+---@param lax? boolean
+---@return integer?
+---@return integer? errpos
+---@nodiscard
+function utf8.len(s, i, j, lax) end
 
 ---
 --- Returns the position (in bytes) where the encoding of the `n`-th character

From 4a9dca6f26ebca27b8f5e45d3af36bccbe1f5067 Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Wed, 26 Mar 2025 12:48:26 +0800
Subject: [PATCH 12/22] fix bug

---
 .../src/diagnostic/checker/missing_fields.rs                 | 2 +-
 .../src/semantic/overload_resolve/mod.rs                     | 5 +++--
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/crates/emmylua_code_analysis/src/diagnostic/checker/missing_fields.rs b/crates/emmylua_code_analysis/src/diagnostic/checker/missing_fields.rs
index 5c0bbdad0..1a3174091 100644
--- a/crates/emmylua_code_analysis/src/diagnostic/checker/missing_fields.rs
+++ b/crates/emmylua_code_analysis/src/diagnostic/checker/missing_fields.rs
@@ -149,7 +149,7 @@ fn record_required_fields(
         return;
     }
 
-    if decl_type.is_nullable() {
+    if decl_type.is_nullable() || decl_type.is_any() {
         optional_type.insert(name);
         return;
     }
diff --git a/crates/emmylua_code_analysis/src/semantic/overload_resolve/mod.rs b/crates/emmylua_code_analysis/src/semantic/overload_resolve/mod.rs
index 6e82589b4..35a0b7660 100644
--- a/crates/emmylua_code_analysis/src/semantic/overload_resolve/mod.rs
+++ b/crates/emmylua_code_analysis/src/semantic/overload_resolve/mod.rs
@@ -83,11 +83,12 @@ fn resolve_signature_by_args(
         };
         let mut total_weight = 0; // 总权重
         let expr_len = expr_types.len();
-
         // 检查每个参数的匹配情况
         for (i, param) in params.iter().enumerate() {
             if i == 0 && jump_param > 0 {
-                continue; // 处理冒号调用时的偏移
+                // 非冒号定义但是冒号调用, 直接认为匹配
+                total_weight += 100;
+                continue;
             }
             let param_type = param.1.as_ref().unwrap_or(&LuaType::Any);
             let expr_idx = i - jump_param;

From 324ae80eb156fee53c6c3f34ccea46ae5669e43a Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Wed, 26 Mar 2025 13:38:03 +0800
Subject: [PATCH 13/22] diagnostic: fix #262

---
 crates/emmylua_code_analysis/locales/lint.yml |  8 ++--
 .../src/db_index/type/types.rs                |  8 ++++
 .../diagnostic/checker/param_type_check.rs    | 45 ++++++++-----------
 .../diagnostic/test/missing_fields_test.rs    | 17 +++++++
 .../src/semantic/type_check/ref_type.rs       |  2 +-
 5 files changed, 49 insertions(+), 31 deletions(-)

diff --git a/crates/emmylua_code_analysis/locales/lint.yml b/crates/emmylua_code_analysis/locales/lint.yml
index ccca63fec..cc63d42e8 100644
--- a/crates/emmylua_code_analysis/locales/lint.yml
+++ b/crates/emmylua_code_analysis/locales/lint.yml
@@ -68,10 +68,10 @@ Should not reassign to iter variable:
   zh_CN: '不应重新赋值给迭代变量'
   zh_HK: '不應重新指定迭代變數'
 
-expected `%{source}` but found `%{found}`:
-  en: expected `%{source}` but found `%{found}`
-  zh_CN: '预期 `%{source}`，但得到 `%{found}`'
-  zh_HK: '期望 `%{source}`，但得到 `%{found}`'
+expected `%{source}` but found `%{found}`. %{reason}:
+  en: expected `%{source}` but found `%{found}`. %{reason}
+  zh_CN: '预期 `%{source}`，但得到 `%{found}`。 %{reason}'
+  zh_HK: '期望 `%{source}`，但得到 `%{found}`。 %{reason}'
 function %{name} may be nil:
   en: function %{name} may be nil
   zh_CN: '函数 %{name} 可能为 nil'
diff --git a/crates/emmylua_code_analysis/src/db_index/type/types.rs b/crates/emmylua_code_analysis/src/db_index/type/types.rs
index 00d71c03a..c190d5010 100644
--- a/crates/emmylua_code_analysis/src/db_index/type/types.rs
+++ b/crates/emmylua_code_analysis/src/db_index/type/types.rs
@@ -262,6 +262,14 @@ impl LuaType {
         }
     }
 
+    pub fn is_optional(&self) -> bool {
+        match self {
+            LuaType::Nil | LuaType::Any | LuaType::Unknown => true,
+            LuaType::Union(u) => u.types.iter().any(|t| t.is_optional()),
+            _ => false,
+        }
+    }
+
     pub fn is_always_truthy(&self) -> bool {
         match self {
             LuaType::Nil | LuaType::Boolean | LuaType::Any | LuaType::Unknown => false,
diff --git a/crates/emmylua_code_analysis/src/diagnostic/checker/param_type_check.rs b/crates/emmylua_code_analysis/src/diagnostic/checker/param_type_check.rs
index a73a28333..7ff2b8a59 100644
--- a/crates/emmylua_code_analysis/src/diagnostic/checker/param_type_check.rs
+++ b/crates/emmylua_code_analysis/src/diagnostic/checker/param_type_check.rs
@@ -138,32 +138,25 @@ fn add_type_check_diagnostic(
     let db = semantic_model.get_db();
     match result {
         Ok(_) => return,
-        Err(reason) => match reason {
-            TypeCheckFailReason::TypeNotMatchWithReason(reason) => {
-                context.add_diagnostic(DiagnosticCode::ParamTypeNotMatch, range, reason, None);
-            }
-            TypeCheckFailReason::TypeNotMatch => {
-                context.add_diagnostic(
-                    DiagnosticCode::ParamTypeNotMatch,
-                    range,
-                    t!(
-                        "expected `%{source}` but found `%{found}`",
-                        source = humanize_type(db, &param_type, RenderLevel::Simple),
-                        found = humanize_type(db, &expr_type, RenderLevel::Simple)
-                    )
-                    .to_string(),
-                    None,
-                );
-            }
-            TypeCheckFailReason::TypeRecursion => {
-                context.add_diagnostic(
-                    DiagnosticCode::ParamTypeNotMatch,
-                    range,
-                    "type recursion".into(),
-                    None,
-                );
-            }
-        },
+        Err(reason) => {
+            let reason_message = match reason {
+                TypeCheckFailReason::TypeNotMatchWithReason(reason) => reason,
+                TypeCheckFailReason::TypeNotMatch => "".to_string(),
+                TypeCheckFailReason::TypeRecursion => "type recursion".to_string(),
+            };
+            context.add_diagnostic(
+                DiagnosticCode::ParamTypeNotMatch,
+                range,
+                t!(
+                    "expected `%{source}` but found `%{found}`. %{reason}",
+                    source = humanize_type(db, &param_type, RenderLevel::Simple),
+                    found = humanize_type(db, &expr_type, RenderLevel::Simple),
+                    reason = reason_message
+                )
+                .to_string(),
+                None,
+            );
+        }
     }
 }
 
diff --git a/crates/emmylua_code_analysis/src/diagnostic/test/missing_fields_test.rs b/crates/emmylua_code_analysis/src/diagnostic/test/missing_fields_test.rs
index 696ba319e..e44ad09d9 100644
--- a/crates/emmylua_code_analysis/src/diagnostic/test/missing_fields_test.rs
+++ b/crates/emmylua_code_analysis/src/diagnostic/test/missing_fields_test.rs
@@ -132,4 +132,21 @@ mod tests {
         "#
         ));
     }
+
+    #[test]
+    fn test_issue_262() {
+        let mut ws = VirtualWorkspace::new();
+        assert!(ws.check_code_for(
+            DiagnosticCode::MissingFields,
+            r#"
+--- @class D11.Opts
+--- @field field? any
+
+--- @param opts D11.Opts
+local function foo(opts) end
+
+foo({})
+        "#
+        ));
+    }
 }
diff --git a/crates/emmylua_code_analysis/src/semantic/type_check/ref_type.rs b/crates/emmylua_code_analysis/src/semantic/type_check/ref_type.rs
index 3350c4cee..77a057e35 100644
--- a/crates/emmylua_code_analysis/src/semantic/type_check/ref_type.rs
+++ b/crates/emmylua_code_analysis/src/semantic/type_check/ref_type.rs
@@ -170,7 +170,7 @@ fn check_ref_type_compact_table(
                     .to_string(),
                 ));
             }
-        } else if source_member_type.is_nullable() {
+        } else if source_member_type.is_optional() {
             continue;
         } else {
             return Err(TypeCheckFailReason::TypeNotMatchWithReason(

From 961b223c48f78477e5c09d1a1c407af1bb5deaa5 Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Wed, 26 Mar 2025 13:57:20 +0800
Subject: [PATCH 14/22] diagnostic: typecheck function

---
 .../diagnostic/test/param_type_check_test.rs   | 18 ++++++++++++++++++
 .../src/semantic/type_check/func_type.rs       |  1 +
 2 files changed, 19 insertions(+)

diff --git a/crates/emmylua_code_analysis/src/diagnostic/test/param_type_check_test.rs b/crates/emmylua_code_analysis/src/diagnostic/test/param_type_check_test.rs
index 216f220ab..c973c51fa 100644
--- a/crates/emmylua_code_analysis/src/diagnostic/test/param_type_check_test.rs
+++ b/crates/emmylua_code_analysis/src/diagnostic/test/param_type_check_test.rs
@@ -329,4 +329,22 @@ mod test {
         "#
         ));
     }
+
+    #[test]
+    fn test_function() {
+        let mut ws = VirtualWorkspace::new_with_init_std_lib();
+
+        assert!(ws.check_code_for(
+            DiagnosticCode::ParamTypeNotMatch,
+            r#"
+            ---@param sorter function
+            ---@return string[]
+            local function getTableKeys(sorter)
+                local keys = {}
+                table.sort(keys, sorter)
+                return keys
+            end
+        "#
+        ));
+    }
 }
diff --git a/crates/emmylua_code_analysis/src/semantic/type_check/func_type.rs b/crates/emmylua_code_analysis/src/semantic/type_check/func_type.rs
index 4f49c928a..a65c7cb26 100644
--- a/crates/emmylua_code_analysis/src/semantic/type_check/func_type.rs
+++ b/crates/emmylua_code_analysis/src/semantic/type_check/func_type.rs
@@ -42,6 +42,7 @@ pub fn check_doc_func_type_compact(
 
             Ok(())
         }
+        LuaType::Function => Ok(()),
         _ => Err(TypeCheckFailReason::TypeNotMatch),
     }
 }

From 8b5af11f755ead0f81254ed314a4c177f9917fd6 Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Wed, 26 Mar 2025 14:19:45 +0800
Subject: [PATCH 15/22] update type_check

---
 .../resources/std/global.lua                  |  2 +-
 .../diagnostic/test/param_type_check_test.rs  | 22 +++++++++++++++++++
 .../src/semantic/type_check/complex_type.rs   |  2 +-
 3 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/crates/emmylua_code_analysis/resources/std/global.lua b/crates/emmylua_code_analysis/resources/std/global.lua
index 462add43d..3a2f9a85f 100644
--- a/crates/emmylua_code_analysis/resources/std/global.lua
+++ b/crates/emmylua_code_analysis/resources/std/global.lua
@@ -231,7 +231,7 @@ function next(table, index) end
 --- See function `next` for the caveats of modifying the table during its
 --- traversal.
 ---@generic K, V
----@param t table<K, V>
+---@param t table<K, V> | V[]
 ---@return fun(tbl: any):K, std.NotNull<V>
 function pairs(t) end
 ---
diff --git a/crates/emmylua_code_analysis/src/diagnostic/test/param_type_check_test.rs b/crates/emmylua_code_analysis/src/diagnostic/test/param_type_check_test.rs
index c973c51fa..7c7811263 100644
--- a/crates/emmylua_code_analysis/src/diagnostic/test/param_type_check_test.rs
+++ b/crates/emmylua_code_analysis/src/diagnostic/test/param_type_check_test.rs
@@ -347,4 +347,26 @@ mod test {
         "#
         ));
     }
+
+    #[test]
+    fn test_table_array() {
+        let mut ws = VirtualWorkspace::new_with_init_std_lib();
+
+        assert!(ws.check_code_for(
+            DiagnosticCode::ParamTypeNotMatch,
+            r#"
+                ---@generic K, V
+                ---@param t table<K, V>
+                ---@return table<V, K>
+                local function revertMap(t)
+                end
+
+                ---@param arr any[]
+                local function sortCallbackOfIndex(arr)
+                    ---@type table<any, integer>
+                    local indexMap = revertMap(arr)
+                end
+        "#
+        ));
+    }
 }
diff --git a/crates/emmylua_code_analysis/src/semantic/type_check/complex_type.rs b/crates/emmylua_code_analysis/src/semantic/type_check/complex_type.rs
index 2291758e2..6b9bf844c 100644
--- a/crates/emmylua_code_analysis/src/semantic/type_check/complex_type.rs
+++ b/crates/emmylua_code_analysis/src/semantic/type_check/complex_type.rs
@@ -211,7 +211,7 @@ pub fn check_complex_type_compact(
                     if source_generic_param.len() == 2 {
                         let key = &source_generic_param[0];
                         let value = &source_generic_param[1];
-                        if key.is_any() && check_type_compact(db, value, base).is_ok() {
+                        if key.is_any() || key.is_integer() && check_type_compact(db, value, base).is_ok() {
                             return Ok(());
                         }
                     }

From 3a73dad3c8fc06001d0b678f2663cbafb979bcec Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Wed, 26 Mar 2025 15:56:28 +0800
Subject: [PATCH 16/22] some update

---
 .../resources/std/debug.lua                   |  7 +++-
 .../diagnostic/test/param_type_check_test.rs  | 40 +++++++++++++++++++
 .../src/semantic/type_check/complex_type.rs   |  5 ++-
 .../src/semantic/type_check/simple_type.rs    |  1 +
 4 files changed, 50 insertions(+), 3 deletions(-)

diff --git a/crates/emmylua_code_analysis/resources/std/debug.lua b/crates/emmylua_code_analysis/resources/std/debug.lua
index 6f56c8237..871a1678c 100644
--- a/crates/emmylua_code_analysis/resources/std/debug.lua
+++ b/crates/emmylua_code_analysis/resources/std/debug.lua
@@ -146,9 +146,11 @@ function debug.getregistry() end
 ---
 --- Variable names starting with '(' (open parenthesis) represent variables with
 --- no known names (variables from chunks saved without debug information).
----@param f integer
+---@param f async fun(...):any...
 ---@param up integer
----@return table
+---@return string name
+---@return any    value
+---@nodiscard
 function debug.getupvalue(f, up) end
 
 ---
@@ -236,6 +238,7 @@ function debug.setlocal(thread, level, var, value) end
 ---@param value T
 ---@param meta? table
 ---@return T value
+---@overload fun(value: table, meta: T): T
 function debug.setmetatable(value, meta) end
 
 ---
diff --git a/crates/emmylua_code_analysis/src/diagnostic/test/param_type_check_test.rs b/crates/emmylua_code_analysis/src/diagnostic/test/param_type_check_test.rs
index 7c7811263..510a935d0 100644
--- a/crates/emmylua_code_analysis/src/diagnostic/test/param_type_check_test.rs
+++ b/crates/emmylua_code_analysis/src/diagnostic/test/param_type_check_test.rs
@@ -369,4 +369,44 @@ mod test {
         "#
         ));
     }
+
+    #[test]
+    fn test_table_class() {
+        let mut ws = VirtualWorkspace::new_with_init_std_lib();
+
+        assert!(ws.check_code_for(
+            DiagnosticCode::ParamTypeNotMatch,
+            r#"
+                ---@param t table
+                local function bar(t)
+                end
+
+                ---@class D11.A
+
+                ---@type D11.A|any
+                local a
+
+                bar(a)
+        "#
+        ));
+    }
+
+    #[test]
+    fn test_table_1() {
+        let mut ws = VirtualWorkspace::new_with_init_std_lib();
+
+        assert!(ws.check_code_for(
+            DiagnosticCode::ParamTypeNotMatch,
+            r#"
+                ---@param t table[]
+                local function bar(t)
+                end
+
+                ---@type table|any
+                local a
+
+                bar(a)
+        "#
+        ));
+    }
 }
diff --git a/crates/emmylua_code_analysis/src/semantic/type_check/complex_type.rs b/crates/emmylua_code_analysis/src/semantic/type_check/complex_type.rs
index 6b9bf844c..eb578b65d 100644
--- a/crates/emmylua_code_analysis/src/semantic/type_check/complex_type.rs
+++ b/crates/emmylua_code_analysis/src/semantic/type_check/complex_type.rs
@@ -80,6 +80,7 @@ pub fn check_complex_type_compact(
                     return Ok(());
                 }
             }
+            LuaType::Any => return Ok(()),
             _ => {}
         },
         LuaType::Tuple(tuple) => {
@@ -211,7 +212,9 @@ pub fn check_complex_type_compact(
                     if source_generic_param.len() == 2 {
                         let key = &source_generic_param[0];
                         let value = &source_generic_param[1];
-                        if key.is_any() || key.is_integer() && check_type_compact(db, value, base).is_ok() {
+                        if key.is_any()
+                            || key.is_integer() && check_type_compact(db, value, base).is_ok()
+                        {
                             return Ok(());
                         }
                     }
diff --git a/crates/emmylua_code_analysis/src/semantic/type_check/simple_type.rs b/crates/emmylua_code_analysis/src/semantic/type_check/simple_type.rs
index bd18500c1..6f3ed7c31 100644
--- a/crates/emmylua_code_analysis/src/semantic/type_check/simple_type.rs
+++ b/crates/emmylua_code_analysis/src/semantic/type_check/simple_type.rs
@@ -32,6 +32,7 @@ pub fn check_simple_type_compact(
                     | LuaType::Global
                     | LuaType::Userdata
                     | LuaType::Instance(_)
+                    | LuaType::Any
             ) {
                 return Ok(());
             }

From c2163a620b5e4bab62eda49a129f20ce075654ff Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Wed, 26 Mar 2025 19:36:46 +0800
Subject: [PATCH 17/22] =?UTF-8?q?completion:=20local=E5=90=8E=E7=9A=84?=
 =?UTF-8?q?=E7=A9=BA=E6=A0=BCfunction=E8=A1=A5=E5=85=A8=E5=BA=94=E5=8F=AA?=
 =?UTF-8?q?=E5=85=81=E8=AE=B8=E4=B8=BB=E5=8A=A8=E8=A7=A6=E5=8F=91?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../src/handlers/completion/completion_builder.rs           | 5 +++++
 .../src/handlers/completion/providers/keywords_provider.rs  | 6 ++++++
 2 files changed, 11 insertions(+)

diff --git a/crates/emmylua_ls/src/handlers/completion/completion_builder.rs b/crates/emmylua_ls/src/handlers/completion/completion_builder.rs
index 06581ca73..29d5493ff 100644
--- a/crates/emmylua_ls/src/handlers/completion/completion_builder.rs
+++ b/crates/emmylua_ls/src/handlers/completion/completion_builder.rs
@@ -70,4 +70,9 @@ impl<'a> CompletionBuilder<'a> {
         }
         self.env_range = (0, 0);
     }
+
+    /// 是否是触发主动补全
+    pub fn is_invoked(&self) -> bool {
+        self.trigger_kind == CompletionTriggerKind::INVOKED
+    }
 }
diff --git a/crates/emmylua_ls/src/handlers/completion/providers/keywords_provider.rs b/crates/emmylua_ls/src/handlers/completion/providers/keywords_provider.rs
index 1197a9e46..58dd8ec8a 100644
--- a/crates/emmylua_ls/src/handlers/completion/providers/keywords_provider.rs
+++ b/crates/emmylua_ls/src/handlers/completion/providers/keywords_provider.rs
@@ -11,6 +11,7 @@ pub fn add_completion(builder: &mut CompletionBuilder) -> Option<()> {
     if builder.is_cancelled() {
         return None;
     }
+
     if is_full_match_keyword(builder).is_some() {
         add_stat_keyword_completions(builder, None);
         return Some(());
@@ -122,12 +123,17 @@ fn add_expr_keyword_completions(builder: &mut CompletionBuilder) -> Option<()> {
 }
 
 fn add_function_keyword_completions(builder: &mut CompletionBuilder) -> Option<()> {
+    // 非主动补全不添加
+    if !builder.is_invoked() {
+        return None;
+    }
     let item = CompletionItem {
         label: "function".to_string(),
         kind: Some(lsp_types::CompletionItemKind::SNIPPET),
         insert_text: Some("function ${1:name}(${2:...})\n\t${0}\nend".to_string()),
         insert_text_format: Some(InsertTextFormat::SNIPPET),
         insert_text_mode: Some(InsertTextMode::ADJUST_INDENTATION),
+        sort_text: Some("0000".to_string()), // 优先级较高
         ..CompletionItem::default()
     };
 

From a8202e4f4658e6c21b4006f3cd75542a3c332fd8 Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Wed, 26 Mar 2025 19:50:22 +0800
Subject: [PATCH 18/22] update std pairs

---
 .../resources/std/global.lua                  |  2 +-
 .../diagnostic/test/param_type_check_test.rs  | 24 +++++++++++++++++++
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/crates/emmylua_code_analysis/resources/std/global.lua b/crates/emmylua_code_analysis/resources/std/global.lua
index 3a2f9a85f..bb52db5df 100644
--- a/crates/emmylua_code_analysis/resources/std/global.lua
+++ b/crates/emmylua_code_analysis/resources/std/global.lua
@@ -231,7 +231,7 @@ function next(table, index) end
 --- See function `next` for the caveats of modifying the table during its
 --- traversal.
 ---@generic K, V
----@param t table<K, V> | V[]
+---@param t table<K, V> | V[] | {[K]: V}
 ---@return fun(tbl: any):K, std.NotNull<V>
 function pairs(t) end
 ---
diff --git a/crates/emmylua_code_analysis/src/diagnostic/test/param_type_check_test.rs b/crates/emmylua_code_analysis/src/diagnostic/test/param_type_check_test.rs
index 510a935d0..f9e84b1bc 100644
--- a/crates/emmylua_code_analysis/src/diagnostic/test/param_type_check_test.rs
+++ b/crates/emmylua_code_analysis/src/diagnostic/test/param_type_check_test.rs
@@ -409,4 +409,28 @@ mod test {
         "#
         ));
     }
+
+    #[test]
+    fn test_pairs() {
+        let mut ws = VirtualWorkspace::new_with_init_std_lib();
+
+        assert!(ws.check_code_for(
+            DiagnosticCode::ParamTypeNotMatch,
+            r#"
+                ---@diagnostic disable: missing-return
+                ---@generic K, V
+                ---@param t table<K, V> | V[] | {[K]: V}
+                ---@return fun(tbl: any):K, std.NotNull<V>
+                local function _pairs(t) end
+
+                ---@class D10.A
+
+                ---@type {[string]: D10.A, _id: D10.A}
+                local a
+
+                for k, v in _pairs(a) do
+                end
+        "#
+        ));
+    }
 }

From 54dc160bb6053e2145374e34e3058bf2897b61f8 Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Wed, 26 Mar 2025 20:16:20 +0800
Subject: [PATCH 19/22] diagnostic: fix AssignTypeMismatch

---
 .../test/assign_type_mismatch_test.rs         | 22 +++++++++++++++++++
 .../src/semantic/infer/infer_binary.rs        |  5 +++++
 2 files changed, 27 insertions(+)

diff --git a/crates/emmylua_code_analysis/src/diagnostic/test/assign_type_mismatch_test.rs b/crates/emmylua_code_analysis/src/diagnostic/test/assign_type_mismatch_test.rs
index f5d3af5cb..fb3e06745 100644
--- a/crates/emmylua_code_analysis/src/diagnostic/test/assign_type_mismatch_test.rs
+++ b/crates/emmylua_code_analysis/src/diagnostic/test/assign_type_mismatch_test.rs
@@ -42,6 +42,28 @@ mod tests {
         ));
     }
 
+    #[test]
+    fn test_3() {
+        let mut ws = VirtualWorkspace::new();
+        assert!(ws.check_code_for_namespace(
+            DiagnosticCode::AssignTypeMismatch,
+            r#"
+                ---@param s    string
+                ---@param i?   integer
+                ---@param j?   integer
+                ---@param lax? boolean
+                ---@return integer?
+                ---@return integer? errpos
+                ---@nodiscard
+                local function get_len(s, i, j, lax) end
+
+                local len = 0
+                ---@diagnostic disable-next-line: need-check-nil
+                len = len + get_len("", 1, 1, true)
+            "#
+        ));
+    }
+
     #[test]
     fn test_issue_193() {
         let mut ws = VirtualWorkspace::new();
diff --git a/crates/emmylua_code_analysis/src/semantic/infer/infer_binary.rs b/crates/emmylua_code_analysis/src/semantic/infer/infer_binary.rs
index 6585fda0c..179ac60df 100644
--- a/crates/emmylua_code_analysis/src/semantic/infer/infer_binary.rs
+++ b/crates/emmylua_code_analysis/src/semantic/infer/infer_binary.rs
@@ -166,6 +166,11 @@ fn infer_binary_expr_add(db: &DbIndex, left: LuaType, right: LuaType) -> InferRe
             }
         };
     }
+    match (left.is_nil(), right.is_nil()) {
+        (true, false) => return Some(right),
+        (false, true) => return Some(left),
+        _ => {}
+    }
 
     infer_binary_custom_operator(db, &left, &right, LuaOperatorMetaMethod::Add)
 }

From f2d6a989020b5e6737f477b3f5786b92df10133b Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Thu, 27 Mar 2025 06:53:47 +0800
Subject: [PATCH 20/22] std update

---
 .../resources/std/io.lua                      | 32 +++++++++++++------
 1 file changed, 22 insertions(+), 10 deletions(-)

diff --git a/crates/emmylua_code_analysis/resources/std/io.lua b/crates/emmylua_code_analysis/resources/std/io.lua
index 602b5f9ef..9d1c1c403 100644
--- a/crates/emmylua_code_analysis/resources/std/io.lua
+++ b/crates/emmylua_code_analysis/resources/std/io.lua
@@ -94,13 +94,25 @@ function io.output(file) end
 ---@return file
 function io.popen(prog, mode) end
 
+---@alias std.readmode
+---| integer
+---| string
+---| "n"   # Reads a number, returning a float or integer based on Lua's conversion grammar.
+---| "a"   # Reads the entire file starting from the current position.
+---| "l"   # Reads a line and ignores the end-of-line marker.
+---| "L"   # Reads a line and preserves the end-of-line marker.
+---| "*n"  # Reads a number, returning a float or integer based on Lua's conversion grammar.
+---| "*a"  # Reads the entire file starting from the current position.
+---| "*l"  # Reads a line and ignores the end-of-line marker.
+---| "*L"  # Reads a line and preserves the end-of-line marker.
+
 ---
 --- Equivalent to `io.input():read(···)`.
---- @param format '*n' | '*a' | '*l' | integer
---- @return string | integer | nil
---- @overload fun(format:'*n'): integer
---- @overload fun(format:'*a' | '*l' | integer): string | nil
-function io.read(format) end
+---@param ... std.readmode
+---@return any
+---@return any ...
+---@nodiscard
+function io.read(...) end
 
 ---
 --- In case of success, returns a handle for a temporary file. This file is
@@ -195,11 +207,11 @@ function file:lines(...) end
 --- *number*: reads a string with up to this number of bytes, returning **nil**
 --- on end of file. If `number` is zero, it reads nothing and returns an
 --- empty string, or **nil** on end of file.
---- @param format '*n' | '*a' | '*l' | integer
---- @return string | integer | nil
---- @overload fun(format:'*n'): integer
---- @overload fun(format:'*a' | '*l' | integer): string | nil
-function file:read(format) end
+---@param ... std.readmode
+---@return any
+---@return any ...
+---@nodiscard
+function file:read(...) end
 
 ---
 --- Sets and gets the file position, measured from the beginning of the

From 6939d67998cb50ce1718bda016c7c05359a7a8ed Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Thu, 27 Mar 2025 07:00:53 +0800
Subject: [PATCH 21/22] fix code

---
 crates/emmylua_code_analysis/resources/std/string.lua  |  2 +-
 .../src/semantic/infer/infer_binary.rs                 | 10 +++++-----
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/crates/emmylua_code_analysis/resources/std/string.lua b/crates/emmylua_code_analysis/resources/std/string.lua
index 0e3d8b1a7..b5a8dd652 100644
--- a/crates/emmylua_code_analysis/resources/std/string.lua
+++ b/crates/emmylua_code_analysis/resources/std/string.lua
@@ -81,7 +81,7 @@ function string.dump(func, strip) end
 ---@param plain?  boolean
 ---@return integer|nil start
 ---@return integer|nil end
----@return any|nil ... captured
+---@return string ... captured
 ---@nodiscard
 function string.find(s, pattern, init, plain) end
 
diff --git a/crates/emmylua_code_analysis/src/semantic/infer/infer_binary.rs b/crates/emmylua_code_analysis/src/semantic/infer/infer_binary.rs
index 179ac60df..a54ae1681 100644
--- a/crates/emmylua_code_analysis/src/semantic/infer/infer_binary.rs
+++ b/crates/emmylua_code_analysis/src/semantic/infer/infer_binary.rs
@@ -67,9 +67,9 @@ fn infer_union(db: &DbIndex, u: &LuaUnionType, right: &LuaType, op: BinaryOperat
     }
 
     match unique_union_types.len() {
-        0 => Some(LuaType::Unknown),
-        1 => Some(unique_union_types.into_iter().next().unwrap()),
-        _ => Some(LuaType::Union(LuaUnionType::new(unique_union_types).into())),
+        0 => Ok(LuaType::Unknown),
+        1 => Ok(unique_union_types.into_iter().next().unwrap()),
+        _ => Ok(LuaType::Union(LuaUnionType::new(unique_union_types).into())),
     }
 }
 
@@ -167,8 +167,8 @@ fn infer_binary_expr_add(db: &DbIndex, left: LuaType, right: LuaType) -> InferRe
         };
     }
     match (left.is_nil(), right.is_nil()) {
-        (true, false) => return Some(right),
-        (false, true) => return Some(left),
+        (true, false) => return Ok(right),
+        (false, true) => return Ok(left),
         _ => {}
     }
 

From 26b67ec8a289d157d7d369f4fc7e88e20eca51d6 Mon Sep 17 00:00:00 2001
From: xuhuanzy <501417909@qq.com>
Date: Thu, 27 Mar 2025 08:12:40 +0800
Subject: [PATCH 22/22] diagnostic: fix MissingFields

---
 .../src/diagnostic/checker/check_field.rs          |  5 +++++
 .../src/diagnostic/test/missing_fields_test.rs     | 14 ++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/crates/emmylua_code_analysis/src/diagnostic/checker/check_field.rs b/crates/emmylua_code_analysis/src/diagnostic/checker/check_field.rs
index 4e9558233..4c1521b09 100644
--- a/crates/emmylua_code_analysis/src/diagnostic/checker/check_field.rs
+++ b/crates/emmylua_code_analysis/src/diagnostic/checker/check_field.rs
@@ -64,6 +64,11 @@ fn check_index_expr(
     let prefix_typ = semantic_model
         .infer_expr(index_expr.get_prefix_expr()?)
         .unwrap_or(LuaType::Unknown);
+
+    if !is_valid_prefix_type(&prefix_typ) {
+        return Some(());
+    }
+
     let index_name = index_key.get_path_part();
     match code {
         DiagnosticCode::InjectField => {
diff --git a/crates/emmylua_code_analysis/src/diagnostic/test/missing_fields_test.rs b/crates/emmylua_code_analysis/src/diagnostic/test/missing_fields_test.rs
index e44ad09d9..bc5e0b1c8 100644
--- a/crates/emmylua_code_analysis/src/diagnostic/test/missing_fields_test.rs
+++ b/crates/emmylua_code_analysis/src/diagnostic/test/missing_fields_test.rs
@@ -149,4 +149,18 @@ foo({})
         "#
         ));
     }
+
+    #[test]
+    fn test_1() {
+        let mut ws = VirtualWorkspace::new();
+        assert!(ws.check_code_for(
+            DiagnosticCode::MissingFields,
+            r#"
+                ---@type table 
+                local a = {}
+
+                print(a[1])
+        "#
+        ));
+    }
 }