1 files changed, 69 insertions, 0 deletions
diff --git a/test/fiddle/test_c_struct_builder.rb b/test/fiddle/test_c_struct_builder.rb
new file mode 100644
index 0000000000..ca44c6cf7a
--- /dev/null
+++ b/test/fiddle/test_c_struct_builder.rb
@@ -0,0 +1,69 @@
+# frozen_string_literal: true
+begin
+  require_relative 'helper'
+  require 'fiddle/struct'
+  require 'fiddle/cparser'
+  require 'fiddle/import'
+rescue LoadError
+end
+
+module Fiddle
+  class TestCStructBuilder < TestCase
+    include Fiddle::CParser
+    extend Fiddle::Importer
+
+    RBasic = struct ['void * flags',
+                     'void * klass' ]
+
+
+    RObject = struct [
+      { 'basic' => RBasic },
+      { 'as'    => union([
+                          { 'heap'=> struct([ 'uint32_t numiv',
+                                              'void * ivptr',
+                                              'void * iv_index_tbl' ]) },
+                             'void *ary[3]' ])}
+    ]
+
+
+    def test_basic_embedded_members
+      assert_equal 0, RObject.offsetof("basic.flags")
+      assert_equal Fiddle::SIZEOF_VOIDP, RObject.offsetof("basic.klass")
+    end
+
+    def test_embedded_union_members
+      assert_equal 2 * Fiddle::SIZEOF_VOIDP, RObject.offsetof("as")
+      assert_equal 2 * Fiddle::SIZEOF_VOIDP, RObject.offsetof("as.heap")
+      assert_equal 2 * Fiddle::SIZEOF_VOIDP, RObject.offsetof("as.heap.numiv")
+      assert_equal 3 * Fiddle::SIZEOF_VOIDP, RObject.offsetof("as.heap.ivptr")
+      assert_equal 4 * Fiddle::SIZEOF_VOIDP, RObject.offsetof("as.heap.iv_index_tbl")
+    end
+
+    def test_as_ary
+      assert_equal 2 * Fiddle::SIZEOF_VOIDP, RObject.offsetof("as.ary")
+    end
+
+    def test_offsetof
+      types, members = parse_struct_signature(['int64_t i','char c'])
+      my_struct = Fiddle::CStructBuilder.create(Fiddle::CStruct, types, members)
+      assert_equal 0, my_struct.offsetof("i")
+      assert_equal Fiddle::SIZEOF_INT64_T, my_struct.offsetof("c")
+    end
+
+    def test_offset_with_gap
+      types, members = parse_struct_signature(['void *p', 'char c', 'long x'])
+      my_struct = Fiddle::CStructBuilder.create(Fiddle::CStruct, types, members)
+
+      assert_equal PackInfo.align(0, ALIGN_VOIDP), my_struct.offsetof("p")
+      assert_equal PackInfo.align(SIZEOF_VOIDP, ALIGN_CHAR), my_struct.offsetof("c")
+      assert_equal SIZEOF_VOIDP + PackInfo.align(SIZEOF_CHAR, ALIGN_LONG), my_struct.offsetof("x")
+    end
+
+    def test_union_offsetof
+      types, members = parse_struct_signature(['int64_t i','char c'])
+      my_struct = Fiddle::CStructBuilder.create(Fiddle::CUnion, types, members)
+      assert_equal 0, my_struct.offsetof("i")
+      assert_equal 0, my_struct.offsetof("c")
+    end
+  end
+end if defined?(Fiddle)