Test dropout state that follows an input layer

Author: milancurcic

test/test_dropout_layer.f90

@@ -1,8 +1,11 @@
 program test_dropout_layer
   use iso_fortran_env, only: stderr => error_unit
-  use nf, only: dropout, layer
+  use nf, only: dropout, input, layer, network
   use nf_dropout_layer, only: dropout_layer
   type(layer) :: layer1
+  type(network) :: net
+  integer :: input_size
+
   logical :: ok = .true.
 
   layer1 = dropout(0.5)
@@ -29,6 +32,39 @@ program test_dropout_layer
 
   end select
 
+  ! Now we're gonna initialize a minimal network with an input layer and a
+  ! dropout that follows and we'll check that the dropout layer has expected
+  ! state.
+  input_size = 10
+  net = network([ &
+    input(input_size), &
+    dropout(0.5) &
+  ])
+
+  select type(layer1_p => net % layers(1) % p)
+    type is(dropout_layer)
+      if (layer1_p % input_size /= input_size) then
+        ok = .false.
+        write(stderr, '(a)') 'dropout layer input size should be the same as the input layer.. failed'
+      end if
+
+      if (.not. allocated(layer1_p % output)) then
+        ok = .false.
+        write(stderr, '(a)') 'dropout layer output array should be allocated.. failed'
+      end if
+
+      if (.not. allocated(layer1_p % gradient)) then
+        ok = .false.
+        write(stderr, '(a)') 'dropout layer gradient array should be allocated.. failed'
+      end if
+
+      if (.not. allocated(layer1_p % mask)) then
+        ok = .false.
+        write(stderr, '(a)') 'dropout layer mask array should be allocated.. failed'
+      end if
+
+  end select
+
   if (ok) then
     print '(a)', 'test_dropout_layer: All tests passed.'
   else