test: add basic test

tests/lean/run/meta2.lean

@@ -0,0 +1,42 @@
+import Init.Lean.Meta
+open Lean
+open Lean.Meta
+
+def dbgOpt : Options :=
+let opt : Options := {};
+let opt := opt.setBool `trace.Meta.debug true;
+let opt := opt.setBool `trace.Meta.isDefEq true;
+let opt := opt.setBool `trace.Meta.isDefEq true;
+opt
+
+def print (msg : MessageData) : MetaM Unit :=
+trace! `Meta.debug msg
+
+def run (mods : List Name) (x : MetaM Unit) (opts : Options := dbgOpt) : IO Unit :=
+do env ← importModules $ mods.map $ fun m => {module := m};
+   match x { config := { opts := opts } } { env := env } with
+   | EStateM.Result.ok _ s    => do
+     s.traceState.traces.forM $ fun m => IO.println $ format m;
+     pure ()
+   | EStateM.Result.error err _ => throw (IO.userError (toString err))
+
+def tst1 : MetaM Unit :=
+do print "----- tst1 -----";
+   let nat := mkConst `Nat;
+   mvar ← mkFreshExprMVar nat;
+   isExprDefEq mvar (mkNatLit 10);
+   isExprDefEq mvar (mkNatLit 10);
+   pure ()
+
+#eval run [`Init.Data.Nat] tst1
+
+def tst2 : MetaM Unit :=
+do print "----- tst2 -----";
+   let nat  := mkConst `Nat;
+   let succ := mkConst `Nat.succ;
+   mvar ← mkFreshExprMVar nat;
+   isExprDefEq (mkApp succ mvar) (mkApp succ (mkNatLit 10));
+   isExprDefEq mvar (mkNatLit 10);
+   pure ()
+
+#eval run [`Init.Data.Nat] tst2