new tester; all tests categorized

tests/gensym/tgensym.nim

@@ -0,0 +1,16 @@
+discard """
+  output: "123100"
+"""
+
+template hygienic(val: expr) =
+  var x = val
+  stdout.write x
+
+var x = 100
+
+hygienic 1
+hygienic 2
+hygienic 3
+
+echo x
+

tests/gensym/tgensymgeneric.nim

@@ -0,0 +1,31 @@
+# We need to open the gensym'ed symbol again so that the instantiation
+# creates a fresh copy; but this is wrong the very first reason for gensym
+# is that scope rules cannot be used! So simply removing 'sfGenSym' does
+# not work. Copying the symbol does not work either because we're already
+# the owner of the symbol! What we need to do is to copy the symbol
+# in the generic instantiation process...
+
+type
+  TA = object
+    x: int
+  TB = object
+    x: string
+
+template genImpl() =
+  var gensymed: T
+  when T is TB:
+    gensymed.x = "abc"
+  else:
+    gensymed.x = 123
+  shallowCopy(result, gensymed)
+
+proc gen[T](x: T): T =
+  genImpl()
+
+var
+  a: TA
+  b: TB
+let x = gen(a)
+let y = gen(b)
+
+echo x.x, " ", y.x