Refactor to deduplicate unit test setup

As some of the setup is the same for each test, the tests can be
sections in a single test which share the same setup instead of copying
it.

Author: thomasspriggs

unit/solvers/smt2_incremental/struct_encoding.cpp

@@ -32,7 +32,7 @@ TEST_CASE(
   REQUIRE(test.struct_encoding.encode(input) == input);
 }
 
-TEST_CASE("struct encoding of struct_tag_type", "[core][smt2_incremental]")
+TEST_CASE("struct encoding of types", "[core][smt2_incremental]")
 {
   const struct_union_typet::componentst components{
     {"foo", unsignedbv_typet{8}}, {"bar", signedbv_typet{16}}};
@@ -41,45 +41,30 @@ TEST_CASE("struct encoding of struct_tag_type", "[core][smt2_incremental]")
   auto test = struct_encoding_test_environmentt::make();
   test.symbol_table.insert(type_symbol);
   struct_tag_typet struct_tag{type_symbol.name};
-  REQUIRE(test.struct_encoding.encode(struct_tag) == bv_typet{24});
-}
-
-TEST_CASE("struct encoding of array of structs", "[core][smt2_incremental]")
-{
-  const struct_union_typet::componentst components{
-    {"foo", unsignedbv_typet{8}}, {"bar", signedbv_typet{16}}};
-  struct_typet struct_type{components};
-  type_symbolt type_symbol{"my_structt", struct_type, ID_C};
-  auto test = struct_encoding_test_environmentt::make();
-  test.symbol_table.insert(type_symbol);
-  struct_tag_typet struct_tag{type_symbol.name};
-  const auto index_type = signedbv_typet{32};
-  const auto array_size = from_integer(5, index_type);
-  array_typet array_of_struct{struct_tag, array_size};
-  array_typet expected_encoded_array{bv_typet{24}, array_size};
-  REQUIRE(
-    test.struct_encoding.encode(array_of_struct) == expected_encoded_array);
-}
-
-TEST_CASE(
-  "struct encoding of array of array of structs",
-  "[core][smt2_incremental]")
-{
-  const struct_union_typet::componentst components{
-    {"foo", unsignedbv_typet{8}}, {"bar", signedbv_typet{16}}};
-  struct_typet struct_type{components};
-  type_symbolt type_symbol{"my_structt", struct_type, ID_C};
-  auto test = struct_encoding_test_environmentt::make();
-  test.symbol_table.insert(type_symbol);
-  struct_tag_typet struct_tag{type_symbol.name};
-  const auto index_type = signedbv_typet{32};
-  const auto array_size_inner = from_integer(4, index_type);
-  const auto array_size_outer = from_integer(2, index_type);
-  array_typet array_of_struct{struct_tag, array_size_inner};
-  array_typet array_of_array_of_struct{array_of_struct, array_size_outer};
-  array_typet expected_encoded_array{
-    array_typet{bv_typet{24}, array_size_inner}, array_size_outer};
-  REQUIRE(
-    test.struct_encoding.encode(array_of_array_of_struct) ==
-    expected_encoded_array);
+  SECTION("direct struct_tag_type encoding")
+  {
+    REQUIRE(test.struct_encoding.encode(struct_tag) == bv_typet{24});
+  }
+  SECTION("array of structs encoding")
+  {
+    const auto index_type = signedbv_typet{32};
+    const auto array_size = from_integer(5, index_type);
+    array_typet array_of_struct{struct_tag, array_size};
+    array_typet expected_encoded_array{bv_typet{24}, array_size};
+    REQUIRE(
+      test.struct_encoding.encode(array_of_struct) == expected_encoded_array);
+  }
+  SECTION("array of array of structs encoding")
+  {
+    const auto index_type = signedbv_typet{32};
+    const auto array_size_inner = from_integer(4, index_type);
+    const auto array_size_outer = from_integer(2, index_type);
+    array_typet array_of_struct{struct_tag, array_size_inner};
+    array_typet array_of_array_of_struct{array_of_struct, array_size_outer};
+    array_typet expected_encoded_array{
+      array_typet{bv_typet{24}, array_size_inner}, array_size_outer};
+    REQUIRE(
+      test.struct_encoding.encode(array_of_array_of_struct) ==
+      expected_encoded_array);
+  }
 }