add a few more tests

tests/freespace_hirom.asm

@@ -0,0 +1,28 @@
+;`+
+;`08000 53 54 41 52 01 00 fe ff 01 02
+;`0fff8 53 54 41 52 fd ff 02 00
+;`1fffd 03
+;`2fff8 53 54 41 52 ff ff 00 00
+;`3ffff 04
+;`58000 53 54 41 52 00 00 ff ff 05
+;`71234 06
+warnings disable Wmapper_already_set
+norom ; hack: this disables checksum generation
+hirom
+
+freecode cleaned
+db $01,$02
+
+freedata cleaned
+skip $fffd
+db $03
+
+freedata cleaned
+skip $ffff
+db $04
+
+freespace cleaned,bank=$05
+db $05
+
+segment bank=$47,start=$471234
+db $06

tests/ratsoverwrite.asm

@@ -0,0 +1,32 @@
+;`+ #2
+;`80000
+;`53 54 41 52 02 00 fd ff 01 02 03
+;`42 00 00 00
+;`53 54 41 52 02 00 fd ff 04 05 06
+;`07 08 09 0a 0b 0c
+;`01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01
+;`fffff 00
+
+; make sure the freespace allocator doesn't overwrite stuff it's not supposed to
+
+if not(canread1($108000))
+    ; first pass
+    freecode cleaned
+    db 1,2,3
+
+    segment
+    fill 4
+
+    freecode cleaned
+    db 4,5,6
+else
+    ; second pass
+    segment
+    db 7,8,9,10,11,12
+
+    segment
+    fillbyte 1 : fill 24
+
+    segment
+    db $42
+endif