refactor generic infer

crates/emmylua_code_analysis/src/compilation/analyzer/lua/for_range_stat.rs

@@ -3,7 +3,8 @@ use emmylua_parser::{LuaAstNode, LuaAstToken, LuaExpr, LuaForRangeStat};
 use crate::{
     compilation::analyzer::unresolve::UnResolveIterVar, infer_expr, instantiate_doc_function,
     tpl_pattern_match_args, DbIndex, InferFailReason, LuaDeclId, LuaInferCache,
-    LuaOperatorMetaMethod, LuaType, LuaTypeCache, TypeOps, TypeSubstitutor, VariadicType,
+    LuaOperatorMetaMethod, LuaType, LuaTypeCache, TplContext, TypeOps, TypeSubstitutor,
+    VariadicType,
 };
 
 use super::LuaAnalyzer;
@@ -149,19 +150,19 @@ pub fn infer_for_range_iter_expr_func(
         return Ok(doc_function.get_variadic_ret());
     }
     let mut substitutor = TypeSubstitutor::new();
+    let mut context = TplContext {
+        db,
+        cache,
+        substitutor: &mut substitutor,
+        root: root,
+    };
     let params = doc_function
         .get_params()
         .iter()
         .map(|(_, opt_ty)| opt_ty.clone().unwrap_or(LuaType::Any))
         .collect::<Vec<_>>();
-    tpl_pattern_match_args(
-        db,
-        cache,
-        &params,
-        &vec![status_param.clone().unwrap()],
-        &root,
-        &mut substitutor,
-    )?;
+
+    tpl_pattern_match_args(&mut context, &params, &vec![status_param.clone().unwrap()])?;
 
     let instantiate_func = if let LuaType::DocFunction(f) =
         instantiate_doc_function(db, &doc_function, &substitutor)

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

@@ -0,0 +1,70 @@
+#[cfg(test)]
+mod test {
+    use crate::VirtualWorkspace;
+
+    #[test]
+    fn test_issue_586() {
+        let mut ws = VirtualWorkspace::new_with_init_std_lib();
+        ws.def(
+            r#"
+            --- @generic T
+            --- @param cb fun(...: T...)
+            --- @param ... T...
+            function invoke1(cb, ...)
+                cb(...)
+            end
+
+            invoke1(
+                function(a, b, c)
+                    _a = a 
+                    _b = b 
+                    _c = c 
+                end,
+                1, "2", "3"
+            )
+            "#,
+        );
+
+        let a_ty = ws.expr_ty("_a");
+        let b_ty = ws.expr_ty("_b");
+        let c_ty = ws.expr_ty("_c");
+
+        assert_eq!(a_ty, ws.ty("integer"));
+        assert_eq!(b_ty, ws.ty("string"));
+        assert_eq!(c_ty, ws.ty("string"));
+    }
+
+    #[test]
+    fn test_issue_658() {
+        let mut ws = VirtualWorkspace::new_with_init_std_lib();
+        ws.def(
+            r#"
+            --- @generic T1, T2, R
+            --- @param fn fun(_:T1..., _:T2...): R...
+            --- @param ... T1...
+            --- @return fun(_:T2...): R...
+            local function curry(fn, ...)
+            local nargs, args = select('#', ...), { ... }
+            return function(...)
+                local nargs2 = select('#', ...)
+                for i = 1, nargs2 do
+                args[nargs + i] = select(i, ...)
+                end
+                return fn(unpack(args, 1, nargs + nargs2))
+            end
+            end
+
+            --- @param a string
+            --- @param b string
+            --- @param c table
+            local function foo(a, b, c) end
+
+            bar = curry(foo, 'a')
+            "#,
+        );
+
+        let bar_ty = ws.expr_ty("bar");
+        let expected = ws.ty("fun(b:string, c:table)");
+        assert_eq!(bar_ty, expected);
+    }
+}

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

@@ -9,6 +9,7 @@ mod diagnostic_disable_test;
 mod export_test;
 mod flow;
 mod for_range_var_infer_test;
+mod generic_test;
 mod infer_str_tpl_test;
 mod inherit_type;
 mod mathlib_test;

crates/emmylua_code_analysis/src/db_index/type/mod.rs

@@ -3,6 +3,7 @@ mod test;
 mod type_decl;
 mod type_ops;
 mod type_owner;
+mod type_visit_trait;
 mod types;
 
 use super::traits::LuaIndex;
@@ -14,6 +15,7 @@ pub use type_decl::{
 };
 pub use type_ops::TypeOps;
 pub use type_owner::{LuaTypeCache, LuaTypeOwner};
+pub use type_visit_trait::TypeVisitTrait;
 pub use types::*;
 
 #[derive(Debug)]

crates/emmylua_code_analysis/src/db_index/type/type_visit_trait.rs

@@ -0,0 +1,7 @@
+use crate::LuaType;
+
+pub trait TypeVisitTrait {
+    fn visit_type<F>(&self, f: &mut F)
+    where
+        F: FnMut(&LuaType);
+}