SPICE-0020: Deferred, type-safe references (#1354)

2026-09-13 13:21:47 +02:00 · 2026-06-23 15:26:06 +02:00
parent b3015a09cc
commit 8a43e51e6b
83 changed files with 2573 additions and 226 deletions
@@ -0,0 +1 @@
+foo: String
@@ -0,0 +1,7 @@
+open module ReferencedModuleWithOutputOverride
+
+foo: String
+
+hidden output: ModuleOutput = new {
+  text = foo
+}
@@ -0,0 +1,134 @@
+import "pkl:math"
+import "pkl:ref"
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String =
+    let (data = reference.getData())
+    let (root = if (data is Resource) data.name else data.toString())
+    let (
+      path =
+        reference
+          .getPath()
+          .map((elem) -> if (elem.isProperty) ".\(elem.property)" else "[\(elem.key)]")
+    )
+      "${\(root)\(path.join(""))}"
+}
+
+local const d: D = new {}
+typealias Ref<T> = ref.Reference<D, T>
+
+abstract class Resource {
+  name: String
+  hidden fixed $: Ref<Resource>
+}
+
+class A extends Resource {
+  id: String
+  hidden outputs: AProperties
+  hidden fixed $: Ref<A> = ref.Reference(d, A, this)
+}
+
+/// Test doc comment
+class AProperties {
+  foo: Int
+  someMapping: Mapping<String, Int?>
+  someMap: Map<MapKey, Int>
+  someListing: Listing<Int>
+  someList: List<Int>
+  nonInt: String
+}
+
+class B extends Resource {
+  id: String
+  hidden outputs: BProperties
+  hidden fixed $: Ref<B> = ref.Reference(d, B, this)
+}
+
+class BProperties {
+  foo: String
+  someMapping: Mapping<String, String?>
+  someMap: Map<MapKey, String>
+  someListing: Listing<String>
+  someList: List<String>
+  nonString: Int
+}
+
+class MapKey {
+  k: Int
+
+  function toString(): String = "key:\(k)"
+}
+
+class K {
+  aId: String | *Ref<String>?
+  bId: String | *Ref<String>?
+  aProperties: AProperties | *Ref<AProperties>?
+  bProperties: BProperties | *Ref<BProperties>?
+  aValues: Listing<Int | Ref<Int?>>?
+  bValues: Listing<String | Ref<String?>>?
+  splitUnion: Ref<Listing<String> | Listing<Int>>?
+}
+
+a: A = new {
+  name = "a"
+  id = "some-a-value"
+}
+
+b: B = new {
+  name = "b"
+  id = "some-b-value"
+}
+
+aOrB: A | B = a
+aRef: Ref<A> = a.$
+bRef: Ref<B> = b.$
+unknownRef: Ref<A | B> = aRef
+unknownRef2: Ref<A> | Ref<B> = aRef
+unknownRef3: Ref<B | A> = aOrB.$
+
+k: K = new {
+  aId = aRef.id
+  bId = bRef.id
+  aProperties = aRef.outputs
+  bProperties = bRef.outputs
+  aValues {
+    aRef.outputs.foo
+    aRef.outputs.someMapping["key"]
+    aRef.outputs.someMap[new MapKey { k = 123 }]
+    aRef.outputs.someListing[0]
+    aRef.outputs.someList[math.maxInt]
+    bRef.outputs.nonString
+  }
+  bValues {
+    bRef.outputs.foo
+    bRef.outputs.someMapping["key"]
+    bRef.outputs.someMap[new MapKey { k = 123 }]
+    bRef.outputs.someListing[0]
+    bRef.outputs.someList[math.maxInt]
+    aRef.outputs.nonInt
+  }
+}
+
+j: K = new {
+  local aRef2 = unknownRef as Ref<A>
+  aProperties = aRef2.outputs
+  splitUnion = unknownRef.outputs.someListing
+}
+
+refInterpolation = "\(aRef.outputs.someListing[1])"
+kInterpolation = "\(k)"
+aValuesJoined = k.aValues.join("\n").replaceAll(Regex("@[a-z0-9]+"), "@<addr>")
+
+// ensure that type arguments that are unions are handled correctly
+typeArgs = ref.Reference(d, TypeHolder, null).prop as Ref<Listing<Number | Boolean | String>>
+class TypeHolder {
+  prop: Listing<String | Boolean | Number>
+}
+
+output {
+  renderer {
+    converters {
+      [ref.Reference] = (it) -> it.toString()
+    }
+  }
+}
@@ -0,0 +1,9 @@
+import "pkl:ref"
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+local d: D = new {}
+typealias Ref<T> = ref.Reference<D, T>
+
+test = ref.Reference(d, String, "") as Ref<Int>
@@ -0,0 +1,9 @@
+import "pkl:ref"
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+typealias Ref<T> = ref.Reference<D, T>
+local d: D = new {}
+
+test = ref.Reference(d, String, "") as Ref<Listing<String(true)>>
@@ -0,0 +1,12 @@
+import "pkl:ref"
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+typealias Ref<T> = ref.Reference<D, T>
+local d: D = new {}
+
+test = ref.Reference(d, String, "") as Ref<Alias1?>
+
+typealias Alias1 = Int | Alias2?
+typealias Alias2 = String(length < 5)
@@ -0,0 +1,12 @@
+import "pkl:ref"
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+typealias RefAlias1 = ref.Reference<D, Alias1?>
+local d: D = new {}
+
+test = ref.Reference(d, String, "") as RefAlias1
+
+typealias Alias1 = Int | Alias2?
+typealias Alias2 = String(length < 5)
@@ -0,0 +1,8 @@
+import "pkl:ref"
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+local d: D = new {}
+
+test = ref.Reference(d, Mapping, "").default
@@ -0,0 +1,8 @@
+import "pkl:ref"
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+local d: D = new {}
+
+test = ref.Reference(d, Listing, "").default
@@ -0,0 +1,8 @@
+import "pkl:ref"
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+local d: D = new {}
+
+test = ref.Reference(d, Dynamic, "").default
@@ -0,0 +1,10 @@
+import "pkl:ref"
+
+import ".../input-helper/errors/ReferencedModule.pkl"
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+local d: D = new {}
+
+test = ref.Reference(d, ReferencedModule.getClass(), "").output
@@ -0,0 +1,10 @@
+import "pkl:ref"
+
+import ".../input-helper/errors/ReferencedModuleWithOutputOverride.pkl"
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+local d: D = new {}
+
+test = ref.Reference(d, ReferencedModuleWithOutputOverride.getClass(), "").output
@@ -0,0 +1,12 @@
+import "pkl:ref"
+
+import ".../input-helper/errors/ReferencedModuleWithOutputOverride.pkl"
+
+class ModuleSubclass extends ReferencedModuleWithOutputOverride
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+local d: D = new {}
+
+test = ref.Reference(d, ModuleSubclass, "").output
@@ -0,0 +1,12 @@
+import "pkl:ref"
+
+class A {
+  foo: String | Int | Boolean
+}
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+local d: D = new {}
+
+test = ref.Reference(d, A, "").foo as ref.Reference<D, Int | Boolean>
@@ -0,0 +1,9 @@
+import "pkl:ref"
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+local d: D = new {}
+typealias Ref<T> = ref.Reference<D, T>
+
+test = ref.Reference(d, String, "") as Ref<Boolean | Int>
@@ -0,0 +1,15 @@
+import "pkl:ref"
+
+class A {
+  foo: String | Int | Boolean
+}
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+local d: D = new {}
+
+local test = ref.Reference(d, A, "").foo
+testInterpolation = "test:\(test)"
+
+// this tests that the interpolation appears in the output when referenceToString throws
@@ -0,0 +1,9 @@
+import "pkl:ref"
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+local d: D = new {}
+typealias Ref<T> = ref.Reference<D, T>
+
+test = ref.Reference(d, String, "") as Ref<Listing<String>>
@@ -0,0 +1,12 @@
+import "pkl:ref"
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+local d: D = new {}
+typealias Ref<T> = ref.Reference<D, T>
+
+test = ref.Reference(d, String, "") as Ref<Alias1?>
+
+typealias Alias1 = Int | Alias2?
+typealias Alias2 = Boolean
@@ -0,0 +1,14 @@
+import "pkl:ref"
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+local d: D = new {}
+typealias Ref<T> = ref.Reference<D, T>
+
+class D2 extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+local d2: D2 = new {}
+
+test = ref.Reference(d2, String, "") as Ref<String>
@@ -0,0 +1,13 @@
+import "pkl:ref"
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+local d: D = new {}
+typealias Ref<T> = ref.Reference<D, T>
+
+class A {
+  b: String
+}
+
+test = ref.Reference(d, String, new A {}).c
@@ -0,0 +1,9 @@
+import "pkl:ref"
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+local d: D = new {}
+typealias Ref<T> = ref.Reference<D, T>
+
+test = ref.Reference(d, List, List())["hi"]
@@ -0,0 +1,9 @@
+import "pkl:ref"
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+typealias Ref<T> = ref.Reference<D, T>
+local d: D = new {}
+
+test = ref.Reference(d, String, "") as Ref<String(true)>
@@ -0,0 +1,9 @@
+import "pkl:ref"
+
+class D extends ref.Domain {
+  function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+}
+typealias Ref<T> = ref.Reference<D, T>
+local d: D = new {}
+
+test = ref.Reference(d, String, "") as Ref<String(true) | Int>
@@ -0,0 +1,60 @@
+a {
+  name = "a"
+  id = "some-a-value"
+}
+b {
+  name = "b"
+  id = "some-b-value"
+}
+aOrB {
+  name = "a"
+  id = "some-a-value"
+}
+aRef = "${a}"
+bRef = "${b}"
+unknownRef = "${a}"
+unknownRef2 = "${a}"
+unknownRef3 = "${a}"
+k {
+  aId = "${a.id}"
+  bId = "${b.id}"
+  aProperties = "${a.outputs}"
+  bProperties = "${b.outputs}"
+  aValues {
+    "${a.outputs.foo}"
+    "${a.outputs.someMapping[key]}"
+    "${a.outputs.someMap[key:123]}"
+    "${a.outputs.someListing[0]}"
+    "${a.outputs.someList[9223372036854775807]}"
+    "${b.outputs.nonString}"
+  }
+  bValues {
+    "${b.outputs.foo}"
+    "${b.outputs.someMapping[key]}"
+    "${b.outputs.someMap[key:123]}"
+    "${b.outputs.someListing[0]}"
+    "${b.outputs.someList[9223372036854775807]}"
+    "${a.outputs.nonInt}"
+  }
+  splitUnion = null
+}
+j {
+  aId = null
+  bId = null
+  aProperties = "${a.outputs}"
+  bProperties = null
+  aValues = null
+  bValues = null
+  splitUnion = "${a.outputs.someListing}"
+}
+refInterpolation = "${a.outputs.someListing[1]}"
+kInterpolation = "new K { aId = Reference(new D {}, String, new A { name = \"a\"; id = \"some-a-value\" }).id; bId = Reference(new D {}, String, new B { name = \"b\"; id = \"some-b-value\" }).id; aProperties = Reference(new D {}, reference#AProperties, new A { name = \"a\"; id = \"some-a-value\" }).outputs; bProperties = Reference(new D {}, reference#BProperties, new B { name = \"b\"; id = \"some-b-value\" }).outputs; aValues { Reference(new D {}, Int, new A { name = \"a\"; id = \"some-a-value\" }).outputs.foo; Reference(new D {}, Int | Null, new A { name = \"a\"; id = \"some-a-value\" }).outputs.someMapping[\"key\"]; Reference(new D {}, Int, new A { name = \"a\"; id = \"some-a-value\" }).outputs.someMap[new MapKey { k = 123 }]; Reference(new D {}, Int, new A { name = \"a\"; id = \"some-a-value\" }).outputs.someListing[0]; Reference(new D {}, Int, new A { name = \"a\"; id = \"some-a-value\" }).outputs.someList[9223372036854775807]; Reference(new D {}, Int, new B { name = \"b\"; id = \"some-b-value\" }).outputs.nonString }; bValues { Reference(new D {}, String, new B { name = \"b\"; id = \"some-b-value\" }).outputs.foo; Reference(new D {}, Null | String, new B { name = \"b\"; id = \"some-b-value\" }).outputs.someMapping[\"key\"]; Reference(new D {}, String, new B { name = \"b\"; id = \"some-b-value\" }).outputs.someMap[new MapKey { k = 123 }]; Reference(new D {}, String, new B { name = \"b\"; id = \"some-b-value\" }).outputs.someListing[0]; Reference(new D {}, String, new B { name = \"b\"; id = \"some-b-value\" }).outputs.someList[9223372036854775807]; Reference(new D {}, String, new A { name = \"a\"; id = \"some-a-value\" }).outputs.nonInt }; splitUnion = null }"
+aValuesJoined = """
+  org.pkl.core.runtime.VmReference@<addr>
+  org.pkl.core.runtime.VmReference@<addr>
+  org.pkl.core.runtime.VmReference@<addr>
+  org.pkl.core.runtime.VmReference@<addr>
+  org.pkl.core.runtime.VmReference@<addr>
+  org.pkl.core.runtime.VmReference@<addr>
+  """
+typeArgs = "${null.prop}"
@@ -20,6 +20,7 @@ pkl:pklbinary
 pkl:platform
 pkl:Project
 pkl:protobuf
+pkl:ref
 pkl:reflect
 pkl:release
 pkl:semver
@@ -0,0 +1,15 @@
+–– Pkl Error ––
+Expected value of type `pkl.ref#Reference<reference1#D, Int>`, but got type `pkl.ref#Reference<reference1#D, String>`.
+Value: Reference(new D {}, String, "")
+
+x | typealias Ref<T> = ref.Reference<D, T>
+                       ^^^^^^^^^^^^^^^^^^^
+at reference1#test (file:///$snippetsDir/input/errors/reference1.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)
@@ -0,0 +1,14 @@
+–– Pkl Error ––
+`Reference` referent type argument may not include type constraints.
+
+x | test = ref.Reference(d, String, "") as Ref<Listing<String(true)>>
+                                           ^^^^^^^^^^^^^^^^^^^^^^^^^^
+at reference10#test (file:///$snippetsDir/input/errors/reference10.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)
@@ -0,0 +1,14 @@
+–– Pkl Error ––
+`Reference` referent type argument may not include type constraints.
+
+x | test = ref.Reference(d, String, "") as Ref<Alias1?>
+                                           ^^^^^^^^^^^^
+at reference11#test (file:///$snippetsDir/input/errors/reference11.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)
@@ -0,0 +1,14 @@
+–– Pkl Error ––
+`Reference` referent type argument may not include type constraints.
+
+x | typealias RefAlias1 = ref.Reference<D, Alias1?>
+                          ^^^^^^^^^^^^^^^^^^^^^^^^^
+at reference12#RefAlias1 (file:///$snippetsDir/input/errors/reference12.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)
@@ -0,0 +1,14 @@
+–– Pkl Error ––
+Cannot find property `default` in object of type `pkl.ref#Reference<reference13#D, Mapping<unknown, unknown>>`.
+
+x | test = ref.Reference(d, Mapping, "").default
+           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at reference13#test (file:///$snippetsDir/input/errors/reference13.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)
@@ -0,0 +1,14 @@
+–– Pkl Error ––
+Cannot find property `default` in object of type `pkl.ref#Reference<reference14#D, Listing<unknown>>`.
+
+x | test = ref.Reference(d, Listing, "").default
+           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at reference14#test (file:///$snippetsDir/input/errors/reference14.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)
@@ -0,0 +1,14 @@
+–– Pkl Error ––
+Cannot find property `default` in object of type `pkl.ref#Reference<reference15#D, Dynamic>`.
+
+x | test = ref.Reference(d, Dynamic, "").default
+           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at reference15#test (file:///$snippetsDir/input/errors/reference15.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)
@@ -0,0 +1,14 @@
+–– Pkl Error ––
+Cannot find property `output` in object of type `pkl.ref#Reference<reference16#D, ReferencedModule>`.
+
+xx | test = ref.Reference(d, ReferencedModule.getClass(), "").output
+            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at reference16#test (file:///$snippetsDir/input/errors/reference16.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)
@@ -0,0 +1,14 @@
+–– Pkl Error ––
+Cannot find property `output` in object of type `pkl.ref#Reference<reference17#D, ReferencedModuleWithOutputOverride>`.
+
+xx | test = ref.Reference(d, ReferencedModuleWithOutputOverride.getClass(), "").output
+            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at reference17#test (file:///$snippetsDir/input/errors/reference17.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)
@@ -0,0 +1,14 @@
+–– Pkl Error ––
+Cannot find property `output` in object of type `pkl.ref#Reference<reference18#D, reference18#ModuleSubclass>`.
+
+xx | test = ref.Reference(d, ModuleSubclass, "").output
+            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at reference18#test (file:///$snippetsDir/input/errors/reference18.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)
@@ -0,0 +1,15 @@
+–– Pkl Error ––
+Expected value of type `pkl.ref#Reference<reference19#D, Int | Boolean>`, but got type `pkl.ref#Reference<reference19#D, Boolean | Int | String>`.
+Value: Reference(new D {}, Boolean | Int | String, "").foo
+
+xx | test = ref.Reference(d, A, "").foo as ref.Reference<D, Int | Boolean>
+                                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at reference19#test (file:///$snippetsDir/input/errors/reference19.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)
@@ -0,0 +1,15 @@
+–– Pkl Error ––
+Expected value of type `pkl.ref#Reference<reference2#D, Boolean | Int>`, but got type `pkl.ref#Reference<reference2#D, String>`.
+Value: Reference(new D {}, String, "")
+
+x | typealias Ref<T> = ref.Reference<D, T>
+                       ^^^^^^^^^^^^^^^^^^^
+at reference2#test (file:///$snippetsDir/input/errors/reference2.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)
@@ -0,0 +1,22 @@
+–– Pkl Error ––
+not supported
+
+x | function renderReference(reference: ref.Reference<D, Any>): String = throw("not supported")
+                                                                         ^^^^^^^^^^^^^^^^^^^^^^
+at reference20#D.renderReference (file:///$snippetsDir/input/errors/reference20.pkl)
+
+xxx | function toString(): String = getDomain().renderReference(this)
+                                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.ref#Reference.toString (pkl:ref)
+
+xx | testInterpolation = "test:\(test)"
+                               ^^^^^^^
+at reference20#testInterpolation (file:///$snippetsDir/input/errors/reference20.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)
@@ -0,0 +1,15 @@
+–– Pkl Error ––
+Expected value of type `pkl.ref#Reference<reference3#D, Listing<String>>`, but got type `pkl.ref#Reference<reference3#D, String>`.
+Value: Reference(new D {}, String, "")
+
+x | typealias Ref<T> = ref.Reference<D, T>
+                       ^^^^^^^^^^^^^^^^^^^
+at reference3#test (file:///$snippetsDir/input/errors/reference3.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)
@@ -0,0 +1,15 @@
+–– Pkl Error ––
+Expected value of type `pkl.ref#Reference<reference4#D, reference4#Alias1?>`, but got type `pkl.ref#Reference<reference4#D, String>`.
+Value: Reference(new D {}, String, "")
+
+x | typealias Ref<T> = ref.Reference<D, T>
+                       ^^^^^^^^^^^^^^^^^^^
+at reference4#test (file:///$snippetsDir/input/errors/reference4.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)
@@ -0,0 +1,15 @@
+–– Pkl Error ––
+Expected value of type `pkl.ref#Reference<reference5#D, String>`, but got type `pkl.ref#Reference<reference5#D2, String>`.
+Value: Reference(new D2 {}, String, "")
+
+x | typealias Ref<T> = ref.Reference<D, T>
+                       ^^^^^^^^^^^^^^^^^^^
+at reference5#test (file:///$snippetsDir/input/errors/reference5.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)
@@ -0,0 +1,14 @@
+–– Pkl Error ––
+Cannot find property `c` in object of type `pkl.ref#Reference<reference6#D, String>`.
+
+xx | test = ref.Reference(d, String, new A {}).c
+            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at reference6#test (file:///$snippetsDir/input/errors/reference6.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)
@@ -0,0 +1,16 @@
+–– Pkl Error ––
+Operator `[]` is not defined for operand types `pkl.ref#Reference<reference7#D, List<unknown>>` and `String`.
+Left operand : Reference(new D {}, List<unknown>, List())
+Right operand: "hi"
+
+x | test = ref.Reference(d, List, List())["hi"]
+           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at reference7#test (file:///$snippetsDir/input/errors/reference7.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)
@@ -0,0 +1,14 @@
+–– Pkl Error ––
+`Reference` referent type argument may not include type constraints.
+
+x | test = ref.Reference(d, String, "") as Ref<String(true)>
+                                           ^^^^^^^^^^^^^^^^^
+at reference8#test (file:///$snippetsDir/input/errors/reference8.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)
@@ -0,0 +1,14 @@
+–– Pkl Error ––
+`Reference` referent type argument may not include type constraints.
+
+x | test = ref.Reference(d, String, "") as Ref<String(true) | Int>
+                                           ^^^^^^^^^^^^^^^^^^^^^^^
+at reference9#test (file:///$snippetsDir/input/errors/reference9.pkl)
+
+xxx | renderer.renderDocument(value)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+at pkl.base#Module.output.text (pkl:base)
+
+xxx | if (renderer is BytesRenderer) renderer.renderDocument(value) else text.encodeToBytes("UTF-8")
+                                                                         ^^^^
+at pkl.base#Module.output.bytes (pkl:base)