Add tests for using Buf type objects and write-num*

S03-buf/write-num.t

@@ -18,27 +18,30 @@ my @values = (
   0e0, 1e0, -1e0, 42e0, -42e0
 );
 
-plan (@methods / 4) * 2
+plan (@methods / 4)
    + @byte-widths * @values * 8
 ;
 
 # run for all possible methods setting / returning unsigned values
 for @methods -> $bytes, $mask, $write, $read {
-  dies-ok { buf8."$write"(0,42) }, "does buf8 $write 0 42 die";
 
   subtest {
-    plan 2 + @endians * 2;
+    plan 3 + @endians * 3;
 
-    dies-ok { buf8.new."$write"(-1,42) },
-      "does $write -1 42 die on uninited";
-    dies-ok { buf8.new(255)."$write"(-1,42) },
-      "does $write -1 42 die on inited";
+    dies-ok { buf8."$write"(-1,42e0) },
+      "does $write -1 42e0 die on type object";
+    dies-ok { buf8.new."$write"(-1,42e0) },
+      "does $write -1 42e0 die on uninited";
+    dies-ok { buf8.new(255)."$write"(-1,42e0) },
+      "does $write -1 42e0 die on inited";
 
     for @endians -> $endian {
-      dies-ok { buf8.new."$write"(-1,42,$endian) },
-        "does $write -1 42 $endian die on uninited";
-      dies-ok { buf8.new(255)."$write"(-1,42,$endian) },
-        "does $write -1 42 $endian die";
+      dies-ok { buf8."$write"(-1,42e0,$endian) },
+        "does $write -1 42e0 $endian die on type object";
+      dies-ok { buf8.new."$write"(-1,42e0,$endian) },
+        "does $write -1 42e0 $endian die on uninited";
+      dies-ok { buf8.new(255)."$write"(-1,42e0,$endian) },
+        "does $write -1 42e0 $endian die";
     }
   }, "did all possible negative offsets die";
 
@@ -53,7 +56,7 @@ for @methods -> $bytes, $mask, $write, $read {
     for ^8 -> $offset {
 
       subtest {
-        plan 3 + @endians * 3 + 3 + @endians * 3;
+        plan 3 * (3 + @endians * 3);
 
         # tests on existing buf
         is-deeply existing."$write"($offset,$value), existing,
@@ -72,6 +75,23 @@ for @methods -> $bytes, $mask, $write, $read {
             "did existing $read $offset $endian give $value";
         }
 
+        # tests on type object
+        my $fromtype := buf8."$write"($offset,$value);
+        ok $fromtype ~~ buf8, 'did we get a buf8?';
+        is $fromtype.elems, $offset + $bytes,
+          "did type $write $offset $value set size {$offset + $bytes}";
+        is $fromtype."$read"($offset), $value,
+          "did type $read $offset give $value";
+
+        for @endians -> $endian {
+          my $fromtype := buf8."$write"($offset,$value,$endian);
+          ok $fromtype ~~ buf8, "did we get a buf8 for $endian?";
+          is $fromtype.elems, $offset + $bytes,
+            "did new $write $offset $value $endian set size {$offset + $bytes}";
+          is $fromtype."$read"($offset,$endian), $value,
+            "did new $read $offset $endian give $value";
+        }
+
         # tests on new buf
         is-deeply (my $buf := buf8.new)."$write"($offset,$value), $buf,
           "does new $write $offset $value return \$buf";