new tester; all tests categorized

tests/discard/tdiscardable.nim

@@ -0,0 +1,13 @@
+# Test the discardable pragma
+
+proc p(x, y: int): int {.discardable.} = 
+  return x + y
+
+# test that it is inherited from generic procs too:
+proc q[T](x, y: T): T {.discardable.} = 
+  return x + y
+
+
+p(8, 2)
+q[float](0.8, 0.2)
+

tests/discard/tneedsdiscard.nim

@@ -0,0 +1,12 @@
+discard """
+  line: 10
+  errormsg: "value returned by statement has to be discarded"
+"""
+
+proc p =
+  var f: TFile
+  echo "hi"
+  
+  open(f, "arg.txt")
+  
+p()