Skip struct test in case that Struct isn't implemented

test/t/struct.rb

 ##
 # Struct ISO Test
 
-assert('Struct', '15.2.18') do
-  Struct.class == Class
-end
+if StructEnabled
+  assert('Struct', '15.2.18') do
+    Struct.class == Class
+  end
 
-assert('Struct superclass', '15.2.18.2') do
-  Struct.superclass == Object
-end
+  assert('Struct superclass', '15.2.18.2') do
+    Struct.superclass == Object
+  end
 
-assert('Struct.new', '15.2.18.3.1') do
-  c = Struct.new(:m1, :m2)
-  c.superclass == Struct and
-    c.members == [:m1,:m2]
-end
+  assert('Struct.new', '15.2.18.3.1') do
+    c = Struct.new(:m1, :m2)
+    c.superclass == Struct and
+      c.members == [:m1,:m2]
+  end
 
-assert('Struct#[]', '15.2.18.4.2') do
-  c = Struct.new(:m1, :m2)
-  cc = c.new(1,2)
-  cc[:m1] == 1 and cc["m2"] == 2
-end
+  assert('Struct#[]', '15.2.18.4.2') do
+    c = Struct.new(:m1, :m2)
+    cc = c.new(1,2)
+    cc[:m1] == 1 and cc["m2"] == 2
+  end
 
-assert('Struct#[]=', '15.2.18.4.3') do
-  c = Struct.new(:m1, :m2)
-  cc = c.new(1,2)
-  cc[:m1] = 3
-  cc[:m1] == 3
-end
+  assert('Struct#[]=', '15.2.18.4.3') do
+    c = Struct.new(:m1, :m2)
+    cc = c.new(1,2)
+    cc[:m1] = 3
+    cc[:m1] == 3
+  end
 
-assert('Struct#each', '15.2.18.4.4') do
-  c = Struct.new(:m1, :m2)
-  cc = c.new(1,2)
-  a = []
-  cc.each{|x|
-    a << x
-  }
-  a[0] == 1 and a[1] == 2
-end
+  assert('Struct#each', '15.2.18.4.4') do
+    c = Struct.new(:m1, :m2)
+    cc = c.new(1,2)
+    a = []
+    cc.each{|x|
+      a << x
+    }
+    a[0] == 1 and a[1] == 2
+  end
 
-assert('Struct#each_pair', '15.2.18.4.5') do
-  c = Struct.new(:m1, :m2)
-  cc = c.new(1,2)
-  a = []
-  cc.each_pair{|k,v|
-    a << [k,v]
-  }
-  a[0] == [:m1, 1] and a[1] == [:m2, 2]
-end
+  assert('Struct#each_pair', '15.2.18.4.5') do
+    c = Struct.new(:m1, :m2)
+    cc = c.new(1,2)
+    a = []
+    cc.each_pair{|k,v|
+      a << [k,v]
+    }
+    a[0] == [:m1, 1] and a[1] == [:m2, 2]
+  end
 
-assert('Struct#members', '15.2.18.4.6') do
-  c = Struct.new(:m1, :m2)
-  cc = c.new(1,2)
-  cc.members == [:m1,:m2]
-end
+  assert('Struct#members', '15.2.18.4.6') do
+    c = Struct.new(:m1, :m2)
+    cc = c.new(1,2)
+    cc.members == [:m1,:m2]
+  end
 
-assert('Struct#select', '15.2.18.4.7') do
-  c = Struct.new(:m1, :m2)
-  cc = c.new(1,2)
-  cc.select{|v| v % 2 == 0} == [2]
+  assert('Struct#select', '15.2.18.4.7') do
+    c = Struct.new(:m1, :m2)
+    cc = c.new(1,2)
+    cc.select{|v| v % 2 == 0} == [2]
+  end
 end
+