Merge pull request #8 from LKedward/fix-empty-tbl-stats

Fix: table stats values for uninitialised table.

Author: LKedward

src/fhash_tbl.f90

@@ -192,19 +192,18 @@ subroutine fhash_tbl_stats(tbl,num_buckets,num_items,num_collisions,max_depth)
 
   integer :: i, depth
 
-  if (.not.allocated(tbl%buckets)) then
-    if (present(num_buckets)) num_buckets = 0
-    return
-  end if
+  ! Initialise stats
+  if (present(num_items)) num_items = 0
+  if (present(num_collisions)) num_collisions = 0
+  if (present(max_depth)) max_depth = 0
+  if (present(num_buckets)) num_buckets = 0
+
+  if (.not.allocated(tbl%buckets)) return
 
   if (present(num_buckets)) then
     num_buckets = size(tbl%buckets)
   end if
 
-  if (present(num_items)) num_items = 0
-  if (present(num_collisions)) num_collisions = 0
-  if (present(max_depth)) max_depth = -1*huge(max_depth)
-
   do i=1,size(tbl%buckets)
 
     depth = node_depth(tbl%buckets(i))

test/test_tbl.f90

@@ -22,6 +22,7 @@ subroutine collect_tbl(testsuite)
         & new_unittest("fhash-tbl-pointer-value", test_fhash_pointer_value), &
         & new_unittest("fhash-tbl-derived-type-value", test_fhash_derived_type_value), &
         & new_unittest("fhash-tbl-invalid-keys", test_fhash_invalid_keys), &
+        & new_unittest("fhash-tbl-stats-empty", test_fhash_stats_empty), &
         & new_unittest("fhash-tbl-unset", test_fhash_unset), &
         & new_unittest("fhash-tbl-high-load", test_fhash_balanced_load) &
         ]
@@ -367,6 +368,41 @@ subroutine test_fhash_invalid_keys(error)
 
   end subroutine test_fhash_invalid_keys
 
+  !>  Check stats for empty table
+  subroutine test_fhash_stats_empty(error)
+    type(error_t), allocatable, intent(out) :: error
+
+    type(fhash_tbl_t) :: tbl
+    integer :: num_buckets, num_items, num_collisions, max_depth
+
+    call tbl%stats(num_buckets,num_items,num_collisions,max_depth)
+
+    if (num_buckets /= 0) then
+      print *, 'num_buckets: ', num_buckets
+      call test_failed(error,'empty table returned non-zero for num_buckets')
+      return
+    end if
+
+    if (num_items /= 0) then
+      print *, 'num_items: ', num_items
+      call test_failed(error,'empty table returned non-zero for num_items')
+      return
+    end if
+
+    if (num_collisions /= 0) then
+      print *, 'num_collisions: ', num_collisions
+      call test_failed(error,'empty table returned non-zero for num_collisions')
+      return
+    end if
+
+    if (max_depth > 0) then
+      print *, 'max_depth: ', max_depth
+      call test_failed(error,'empty table returned positive for max_depth')
+      return
+    end if
+
+  end subroutine test_fhash_stats_empty
+
 
   !>  Store lots of values and check stats
   subroutine test_fhash_balanced_load(error)