From b637b3f4465f240afa2c710541ff0dc22108c9c5 Mon Sep 17 00:00:00 2001
From: fennecdjay <fennecdjay@gmail.com>
Date: Sat, 16 Jul 2022 17:32:12 +0200
Subject: [PATCH] :art: Improve late and array semantics

---
 include/parse.h                    |  2 ++
 src/lib/opfunc.c                   |  4 ++++
 src/parse/scan1.c                  | 20 +++++++++++++++-----
 tests/array/array0.gw              |  7 +++++++
 tests/array/array1.gw              |  3 +++
 tests/array/array2.gw              |  1 +
 tests/array/array3.gw              |  3 +++
 tests/error/abstract_array.gw      |  2 +-
 tests/error/invalid_array_acces.gw |  2 +-
 9 files changed, 37 insertions(+), 7 deletions(-)
 create mode 100644 tests/array/array0.gw
 create mode 100644 tests/array/array1.gw
 create mode 100644 tests/array/array2.gw
 create mode 100644 tests/array/array3.gw

diff --git a/include/parse.h b/include/parse.h
index 6617a81e..fd03f95e 100644
--- a/include/parse.h
+++ b/include/parse.h
@@ -120,4 +120,6 @@ ANN static inline bool not_upvalue(const Env env, const Value v) {
       (v->from->owner_class && isa(v->from->owner_class, env->class_def) > 0) ||
       nspc_lookup_value1(env->curr, insert_symbol(v->name));
 }
+
+ANN m_bool abstract_array(const Env env, const Array_Sub array);
 #endif
diff --git a/src/lib/opfunc.c b/src/lib/opfunc.c
index 41fbf850..f9a46ce2 100644
--- a/src/lib/opfunc.c
+++ b/src/lib/opfunc.c
@@ -118,6 +118,10 @@ OP_CHECK(opck_new) {
   Exp_Unary *unary = (Exp_Unary *)data;
   const Array_Sub array = unary->ctor.td->array;
   DECL_ON(const Type, t, = known_type(env, unary->ctor.td));
+  if(array) {
+    const Type base = array_base(t);
+    if(GET_FLAG(base, abstract)) CHECK_BB(abstract_array(env, array));
+  }
   CHECK_BN(ensure_traverse(env, t));
   if (type_ref(t))
     ERR_N(unary->ctor.td->pos, _("can't use 'new' on ref type '%s'\n"), t->name);
diff --git a/src/parse/scan1.c b/src/parse/scan1.c
index b04f1818..24710be2 100644
--- a/src/parse/scan1.c
+++ b/src/parse/scan1.c
@@ -96,8 +96,14 @@ static inline bool array_ref(const Array_Sub array) {
   return array && !array->exp;
 }
 
-static inline bool array_ref2(const Array_Sub array) {
-  return array && !(array->exp && exp_is_zero(array->exp));
+ANN m_bool abstract_array(const Env env, const Array_Sub array) {
+  Exp e = array->exp;
+  while(e) {
+    if(!exp_is_zero(e))
+      ERR_B(e->pos, _("arrays of abstract type should use `0` size"));
+    e = e->next;
+  }
+  return GW_OK;
 }
 
 ANN static m_bool scan1_decl(const Env env, Exp_Decl *const decl) {
@@ -107,9 +113,13 @@ ANN static m_bool scan1_decl(const Env env, Exp_Decl *const decl) {
   Type t = decl->type;
   CHECK_BB(scan1_defined(env, vd));
   const Type base = array_base_simple(t);
-  if ((!GET_FLAG(decl->td, late) && GET_FLAG(base, abstract)) && array_ref2(decl->td->array))
-    ERR_B(vd->pos, _("arrays of abstract type '%s' must be declared empty"),
-          base->name);
+  if(decl->td->array) {
+    if (!GET_FLAG(decl->td, late) && !decl->td->array->exp)
+      ERR_B(decl->td->pos, _("arrays with no expressions should be declared `late`"));
+    if (GET_FLAG(decl->td, late) && decl->td->array->exp)
+      ERR_B(decl->td->array->exp->pos, _("late array should have no size"));
+    if (GET_FLAG(base, abstract)) CHECK_BB(abstract_array(env, decl->td->array));
+  }
   const Value v = vd->value =
       vd->value ?: new_value(env, t, s_name(vd->xid), vd->pos);
   nspc_add_value(env->curr, vd->xid, v);
diff --git a/tests/array/array0.gw b/tests/array/array0.gw
new file mode 100644
index 00000000..b091f579
--- /dev/null
+++ b/tests/array/array0.gw
@@ -0,0 +1,7 @@
+class abstract C {
+
+}
+
+class D {
+    var C[2] modules;
+}
diff --git a/tests/array/array1.gw b/tests/array/array1.gw
new file mode 100644
index 00000000..7117ca82
--- /dev/null
+++ b/tests/array/array1.gw
@@ -0,0 +1,3 @@
+class abstract C {}
+
+late C[2] c;
diff --git a/tests/array/array2.gw b/tests/array/array2.gw
new file mode 100644
index 00000000..59978267
--- /dev/null
+++ b/tests/array/array2.gw
@@ -0,0 +1 @@
+var int[] i;
diff --git a/tests/array/array3.gw b/tests/array/array3.gw
new file mode 100644
index 00000000..cbce2289
--- /dev/null
+++ b/tests/array/array3.gw
@@ -0,0 +1,3 @@
+class abstract C {}
+
+new C[2];
diff --git a/tests/error/abstract_array.gw b/tests/error/abstract_array.gw
index d89b9016..841e285d 100644
--- a/tests/error/abstract_array.gw
+++ b/tests/error/abstract_array.gw
@@ -1,2 +1,2 @@
-#! [contains] must be declared empty
+#! [contains] arrays of abstract type
 var Shred[12] shreds;
diff --git a/tests/error/invalid_array_acces.gw b/tests/error/invalid_array_acces.gw
index cee8891e..86ee14e4 100644
--- a/tests/error/invalid_array_acces.gw
+++ b/tests/error/invalid_array_acces.gw
@@ -1,3 +1,3 @@
 #! [contains] invalid array access expression
-var int[] j;
+var int[2] j;
 j[1,2,3,4] => i;
-- 
2.43.0