generic issues test cases (#24028)

closes #1969, closes #7547, closes #7737, closes #11838, closes #12283,
closes #12714, closes #12720, closes #14053, closes #16118, closes
#19670, closes #22645

I was going to wait on these but regression tests even for recent PRs
are turning out to be important in wide reaching PRs like #24010.

The other issues with the working label felt either finnicky (#7385,
#9156, #12732, #15247), excessive to test (#12405, #12424, #17527), or I
just don't know what fixed them/what the issue was (#16128: the PR link
gives a server error by Github, #12457, #12487).

tests/generics/tbracketinstantiation.nim

@@ -0,0 +1,86 @@
+discard """
+  nimout: '''
+type
+  Bob = object
+type
+  Another = object
+'''
+"""
+
+block: # issue #22645
+  type
+    Opt[T] = object
+    FutureBase = ref object of RootObj
+    Future[T] = ref object of FutureBase ## Typed future.
+      internalValue: T ## Stored value
+  template err[T](E: type Opt[T]): E = E()
+  proc works(): Future[Opt[int]] {.stackTrace: off, gcsafe, raises: [].} =
+    var chronosInternalRetFuture: FutureBase
+    template result(): untyped {.used.} =
+      Future[Opt[int]](chronosInternalRetFuture).internalValue
+    result = err(type(result))
+  proc breaks(): Future[Opt[int]] {.stackTrace: off, gcsafe, raises: [].} =
+    var chronosInternalRetFuture: FutureBase
+    template result(): untyped {.used.} =
+      cast[Future[Opt[int]]](chronosInternalRetFuture).internalValue
+    result = err(type(result))
+
+import macros
+
+block: # issue #16118
+  macro thing(name: static[string]) =
+    result = newStmtList(
+      nnkTypeSection.newTree(
+        nnkTypeDef.newTree(
+          ident(name),
+          newEmptyNode(),
+          nnkObjectTy.newTree(
+            newEmptyNode(),
+            newEmptyNode(),
+            nnkRecList.newTree()))))
+  template foo(name: string): untyped =
+    thing(name)
+  expandMacros:
+    foo("Bob")
+  block:
+    expandMacros:
+      foo("Another")
+
+block: # issue #19670
+  type
+    Past[Z] = object
+    OpenObject = object
+
+  macro rewriter(prc: untyped): untyped =
+    prc.body.add(nnkCall.newTree(
+      prc.params[0]
+    ))
+    prc
+
+  macro macroAsync(name, restype: untyped): untyped =
+    quote do:
+      proc `name`(): Past[seq[`restype`]] {.rewriter.} = discard
+
+  macroAsync(testMacro, OpenObject)
+
+import asyncdispatch
+
+block: # issue #11838 long
+  type
+    R[P] = object
+      updates: seq[P]
+    D[T, P] = ref object
+      ps: seq[P]
+      t: T
+  proc newD[T, P](ps: seq[P], t: T): D[T, P] =
+    D[T, P](ps: ps, t: t)
+  proc loop[T, P](d: D[T, P]) =
+    var results = newSeq[Future[R[P]]](10)
+  let d = newD[string, int](@[1], "")
+  d.loop()
+
+block: # issue #11838 minimal
+  type R[T] = object
+  proc loop[T]() =
+    discard newSeq[R[R[T]]]()
+  loop[int]()

tests/generics/tmacroinjectedsym.nim

@@ -172,3 +172,15 @@ block: # issue #23865
       return $error
     "ok"
   doAssert g(int) == "f"
+
+import sequtils
+
+block: # issue #12283
+  var b = 5
+  type Foo[T] = object
+    h, w: int
+  proc bar[T](foos: seq[Foo[T]]): T =
+    let w = foldl(foos, a + b.w, 0)
+    w
+  let foos = @[Foo[int](h: 3, w: 5), Foo[int](h: 4, w: 6)]
+  doAssert bar(foos) == 11

tests/generics/tuninstantiatedgenericcalls.nim

@@ -294,6 +294,37 @@ block: # issue #22647
   var x: b[4]
   x.p()
 
+block: # issue #1969
+  type ZeroGenerator = object
+  proc next(g: ZeroGenerator): int = 0
+  # This compiles.
+  type TripleOfInts = tuple
+    a, b, c: typeof(new(ZeroGenerator)[].next)
+  # This raises a compiler error before it's even instantiated.
+  # The `new` proc can't be resolved because `Generator` is not defined.
+  type TripleLike[Generator] = tuple
+    a, b, c: typeof(new(Generator)[].next)
+
+import std/atomics
+
+block: # issue #12720
+  const CacheLineSize = 128
+  type
+    Enqueueable = concept x, type T
+      x is ptr
+      x.next is Atomic[pointer]
+    MyChannel[T: Enqueueable] = object
+      pad: array[CacheLineSize - sizeof(default(T)[]), byte]
+      dummy: typeof(default(T)[])
+
+block: # issue #12714
+  type
+    Enqueueable = concept x, type T
+      x is ptr
+      x.next is Atomic[pointer]
+    MyChannel[T: Enqueueable] = object
+      dummy: type(default(T)[])
+
 when false: # issue #22342, type section version of #22607
   type GenAlias[isInt: static bool] = (
     when isInt:

tests/macros/tgettypeinst7737.nim

@@ -0,0 +1,61 @@
+discard """
+  nimout: '''
+seq[int]
+CustomSeq[int]
+'''
+"""
+
+import macros, typetraits, sequtils
+
+block: # issue #7737 original
+  type
+    CustomSeq[T] = object
+      data: seq[T]
+
+  proc getSubType(T: NimNode): NimNode =
+    echo getTypeInst(T).repr
+    result = getTypeInst(T)[1]
+
+  macro typed_helper(x: varargs[typed]): untyped =
+    let foo = getSubType(x[0])
+    result = quote do: discard
+
+  macro untyped_heavylifting(x: varargs[untyped]): untyped =
+    var containers = nnkArgList.newTree()
+    for arg in x:
+      case arg.kind:
+      of nnkInfix:
+        if eqIdent(arg[0], "in"):
+          containers.add arg[2]
+      else:
+        discard
+    result = quote do:
+      typed_helper(`containers`)
+  var a, b, c: seq[int]
+  untyped_heavylifting z in c, x in a, y in b:
+    discard
+  ## The following gives me CustomSeq instead
+  ## of CustomSeq[int] in getTypeInst
+  var u, v, w: CustomSeq[int]
+  untyped_heavylifting z in u, x in v, y in w:
+    discard
+
+block: # issue #7737 comment
+  type
+    CustomSeq[T] = object
+      data: seq[T]
+  # when using just one argument, `foo` and `bar` should be exactly
+  # identical.
+  macro foo(arg: typed): string =
+    result = newLit(arg.getTypeInst.repr)
+  macro bar(args: varargs[typed]): untyped =
+    result = newTree(nnkBracket)
+    for arg in args:
+      result.add newLit(arg.getTypeInst.repr)
+  var
+    a: seq[int]
+    b: CustomSeq[int]
+  doAssert foo(a) == "seq[int]"
+  doAssert bar(a) == ["seq[int]"]
+  doAssert foo(b) == "CustomSeq[int]"
+  doAssert bar(b) == ["CustomSeq[int]"]

tests/proc/tstaticsignature.nim

@@ -192,6 +192,37 @@ block: # issue #4990 comment
   let bar = Bar(curIndex: 0)
   doAssert bar.next() == meB
 
+block: # issue #14053
+  template returnType(value: static[int]): typedesc =
+    when value == 1:
+      int
+    else:
+      float
+  proc fun(value: static[int]): returnType(value) = discard
+  doAssert fun(1) is int
+  template returnType2(value: static[int]): typedesc =
+    int
+  proc fun2(value: static[int]): returnType2(value) = discard
+  doAssert fun2(1) is int
+
+block: # issue #7547
+  macro foo(N: static[int]): untyped =
+    result = getType(int)
+  type
+    Foo[N: static[int]] = foo(N)
+    ContainsFoo[N: static[int]] = object
+      Ffoo: Foo[N]
+  proc initFoo(N: static[int]): Foo[N] = discard
+  proc initContainsFoo(size: static[int]): ContainsFoo[size] = discard
+  var a: Foo[10] # Works
+  doAssert a is int
+  let b = initFoo(10) # Works
+  doAssert b is int
+  let c = ContainsFoo[5]() # Works
+  doAssert c.Ffoo is int
+  let z = initContainsFoo(5) # Error: undeclared identifier: 'N'
+  doAssert z.Ffoo is int
+
 when false: # issue #22607, needs nkWhenStmt to be handled like nkRecWhen
   proc test[x: static bool](
     t: (