diagnostic

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'

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
 
 ---

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
 
@@ -114,7 +113,7 @@ 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
 
@@ -232,7 +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[] | {[K]: V}
 ---@return fun(tbl: any):K, std.NotNull<V>
 function pairs(t) end
 ---

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

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 string ... 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

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
 

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

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);

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),
     }
 }

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
+
+        "#
+        ));
+    }
 }

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,

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 => {
@@ -92,3 +97,22 @@ 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,
+        }
+    }
+}

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())
+}