1 files changed, 169 insertions, 0 deletions
diff --git a/tests/stdlib/tjsonmacro.nim b/tests/stdlib/tjsonmacro.nim
new file mode 100644
index 000000000..345c5a2fc
--- /dev/null
+++ b/tests/stdlib/tjsonmacro.nim
@@ -0,0 +1,169 @@
+discard """
+  file: "tjsonmacro.nim"
+  output: ""
+"""
+import json, strutils
+
+when isMainModule:
+  # Tests inspired by own use case (with some additional tests).
+  # This should succeed.
+  type
+    Point[T] = object
+      x, y: T
+
+    ReplayEventKind* = enum
+      FoodAppeared, FoodEaten, DirectionChanged
+
+    ReplayEvent* = object
+      time*: float
+      case kind*: ReplayEventKind
+      of FoodAppeared, FoodEaten:
+        foodPos*: Point[float]
+      of DirectionChanged:
+        playerPos*: float
+
+    Replay* = ref object
+      events*: seq[ReplayEvent]
+      test: int
+      test2: string
+      test3: bool
+      testNil: string
+
+  var x = Replay(
+    events: @[
+      ReplayEvent(
+        time: 1.2345,
+        kind: FoodEaten,
+        foodPos: Point[float](x: 5.0, y: 1.0)
+      )
+    ],
+    test: 18827361,
+    test2: "hello world",
+    test3: true,
+    testNil: nil
+  )
+
+  let node = %x
+
+  let y = to(node, Replay)
+  doAssert y.events[0].time == 1.2345
+  doAssert y.events[0].kind == FoodEaten
+  doAssert y.events[0].foodPos.x == 5.0
+  doAssert y.events[0].foodPos.y == 1.0
+  doAssert y.test == 18827361
+  doAssert y.test2 == "hello world"
+  doAssert y.test3
+  doAssert y.testNil.isNil
+
+  # Test for custom object variants (without an enum) and with an else branch.
+  block:
+    type
+      TestVariant = object
+        name: string
+        case age: uint8
+        of 2:
+          preSchool: string
+        of 8:
+          primarySchool: string
+        else:
+          other: int
+
+    var node = %{
+      "name": %"Nim",
+      "age": %8,
+      "primarySchool": %"Sandtown"
+    }
+
+    var result = to(node, TestVariant)
+    doAssert result.age == 8
+    doAssert result.name == "Nim"
+    doAssert result.primarySchool == "Sandtown"
+
+    node = %{
+      "name": %"⚔️Foo☢️",
+      "age": %25,
+      "other": %98
+    }
+
+    result = to(node, TestVariant)
+    doAssert result.name == node["name"].getStr()
+    doAssert result.age == node["age"].getNum().uint8
+    doAssert result.other == node["other"].getNum()
+
+  # TODO: Test object variant with set in of branch.
+  # TODO: Should we support heterogenous arrays?
+
+  # Tests that verify the error messages for invalid data.
+  block:
+    type
+      Person = object
+        name: string
+        age: int
+
+    var node = %{
+      "name": %"Dominik"
+    }
+
+    try:
+      discard to(node, Person)
+      doAssert false
+    except KeyError as exc:
+      doAssert("age" in exc.msg)
+    except:
+      doAssert false
+
+    node["age"] = %false
+
+    try:
+      discard to(node, Person)
+      doAssert false
+    except JsonKindError as exc:
+      doAssert("age" in exc.msg)
+    except:
+      doAssert false
+
+    type
+      PersonAge = enum
+        Fifteen, Sixteen
+
+      PersonCase = object
+        name: string
+        case age: PersonAge
+        of Fifteen:
+          discard
+        of Sixteen:
+          id: string
+
+    try:
+      discard to(node, PersonCase)
+      doAssert false
+    except JsonKindError as exc:
+      doAssert("age" in exc.msg)
+    except:
+      doAssert false
+
+  # Test the example in json module.
+  block:
+    let jsonNode = parseJson("""
+      {
+        "person": {
+          "name": "Nimmer",
+          "age": 21
+        },
+        "list": [1, 2, 3, 4]
+      }
+    """)
+
+    type
+      Person = object
+        name: string
+        age: int
+
+      Data = object
+        person: Person
+        list: seq[int]
+
+    var data = to(jsonNode, Data)
+    doAssert data.person.name == "Nimmer"
+    doAssert data.person.age == 21
+    doAssert data.list == @[1, 2, 3, 4]
\ No newline at end of file