Arc global (#20768)

* temp

* unsure

* fix condition

* port macro arc runable examples to one file

* trigger doc ci

* fix

Co-authored-by: ringabout <43030857+ringabout@users.noreply.github.com>

compiler/injectdestructors.nim

@@ -490,7 +490,7 @@ proc pVarTopLevel(v: PNode; c: var Con; s: var Scope; res: PNode) =
       res.add newTree(nkFastAsgn, v, genDefaultCall(v.typ, c, v.info))
   elif sfThread notin v.sym.flags and sfCursor notin v.sym.flags:
     # do not destroy thread vars for now at all for consistency.
-    if sfGlobal in v.sym.flags and s.parent == nil: #XXX: Rethink this logic (see tarcmisc.test2)
+    if {sfGlobal, sfPure} <= v.sym.flags or sfGlobal in v.sym.flags and s.parent == nil:
       c.graph.globalDestructors.add c.genDestroy(v)
     else:
       s.final.add c.genDestroy(v)

tests/arc/tarc_macro.nim

@@ -0,0 +1,46 @@
+import macros
+
+var destroyCalled = false
+macro bar() =
+  let s = newTree(nnkAccQuoted, ident"=destroy")
+  # let s = ident"`=destroy`" # this would not work
+  result = quote do:
+    type Foo = object
+    # proc `=destroy`(a: var Foo) = destroyCalled = true # this would not work
+    proc `s`(a: var Foo) = destroyCalled = true
+    block:
+      let a = Foo()
+bar()
+doAssert destroyCalled
+
+# custom `op`
+var destroyCalled2 = false
+macro bar(ident) =
+  var x = 1.5
+  result = quote("@") do:
+    type Foo = object
+    let `@ident` = 0 # custom op interpolated symbols need quoted (``)
+    proc `=destroy`(a: var Foo) =
+      doAssert @x == 1.5
+      doAssert compiles(@x == 1.5)
+      let b1 = @[1,2]
+      let b2 = @@[1,2]
+      doAssert $b1 == "[1, 2]"
+      doAssert $b2 == "@[1, 2]"
+      destroyCalled2 = true
+    block:
+      let a = Foo()
+bar(someident)
+doAssert destroyCalled2
+
+proc `&%`(x: int): int = 1
+proc `&%`(x, y: int): int = 2
+
+macro bar2() =
+  var x = 3
+  result = quote("&%") do:
+    var y = &%x # quoting operator
+    doAssert &%&%y == 1 # unary operator => need to escape
+    doAssert y &% y == 2 # binary operator => no need to escape
+    doAssert y == 3
+bar2()

tests/arc/tarcmisc.nim

@@ -124,7 +124,7 @@ proc test(count: int) =
 test(3)
 
 proc test2(count: int) =
-  #block: #XXX: Fails with block currently
+  block: #XXX: Fails with block currently
     var v {.global.} = newVariable(20)
 
     var count = count - 1