new tester; all tests categorized

tests/borrow/tborrow.nim

@@ -0,0 +1,21 @@
+discard """
+  output: "4887 true"
+"""
+
+# test the new borrow feature that works with generics:
+
+proc `++`*[T: int | float](a, b: T): T =
+  result = a + b
+  
+type
+  DI = distinct int
+  DF = distinct float
+  DS = distinct string
+  
+proc `++`(x, y: DI): DI {.borrow.}
+proc `++`(x, y: DF): DF {.borrow.}
+
+proc `$`(x: DI): string {.borrow.}
+proc `$`(x: DF): string {.borrow.}
+
+echo  4544.DI ++ 343.di, " ", (4.5.df ++ 0.5.df).float == 5.0

tests/borrow/tinvalidborrow.nim

@@ -0,0 +1,17 @@
+discard """
+  line: 11
+  errormsg: "no symbol to borrow from found"
+"""
+
+# bug #516
+
+type
+  TAtom = culong
+
+proc `==`*(a, b: TAtom): bool {.borrow.}
+
+var
+  d, e: TAtom
+
+echo( $(d == e) )
+