diff --git a/internal/putil/putil.go b/internal/putil/putil.go
index f88f446..1d8a3f9 100644
--- a/internal/putil/putil.go
+++ b/internal/putil/putil.go
@@ -15,7 +15,10 @@
 // Package putil contains utility functions for working with [resource.PropertyValue]s.
 package putil
 
-import "github.com/pulumi/pulumi/sdk/v3/go/common/resource"
+import (
+	"github.com/pulumi/pulumi/sdk/v3/go/common/resource"
+	"github.com/pulumi/pulumi/sdk/v3/go/common/util/contract"
+)
 
 // IsComputed checks if v is some form of a computed/unknown value.
 func IsComputed(v resource.PropertyValue) bool {
@@ -106,6 +109,8 @@ func MakeKnown(v resource.PropertyValue) resource.PropertyValue {
 // 2. It doesn't panic when computed values are present.
 func DeepEquals(a, b resource.PropertyValue) bool {
 	a, b = foldOutputValue(a), foldOutputValue(b)
+	contract.Assertf(!a.IsSecret() && !b.IsSecret(), "Secrets should be Outputs at this point")
+	contract.Assertf(!a.IsComputed() && !b.IsComputed(), "Computed should be Outputs at this point")
 	switch {
 	case a.IsOutput() && b.IsOutput():
 		a, b := a.OutputValue(), b.OutputValue()
diff --git a/internal/putil/putil_test.go b/internal/putil/putil_test.go
new file mode 100644
index 0000000..d38874e
--- /dev/null
+++ b/internal/putil/putil_test.go
@@ -0,0 +1,103 @@
+// Copyright 2024, Pulumi Corporation.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package putil_test
+
+import (
+	"testing"
+
+	"github.com/pulumi/pulumi-go-provider/internal/putil"
+	rresource "github.com/pulumi/pulumi-go-provider/internal/rapid/resource"
+	r "github.com/pulumi/pulumi/sdk/v3/go/common/resource"
+	"github.com/pulumi/pulumi/sdk/v3/go/common/resource/urn"
+	"github.com/stretchr/testify/assert"
+	"pgregory.net/rapid"
+)
+
+func TestRapidDeepEqual(t *testing.T) {
+	t.Parallel()
+
+	t.Run("reflexivity", rapid.MakeCheck(func(t *rapid.T) { //nolint:paralleltest
+		value := rresource.PropertyValue(5).Draw(t, "value")
+		assert.True(t, putil.DeepEquals(value, value))
+	}))
+
+	// Check that "distinct" values never equal themselves.
+	t.Run("distinct-values", rapid.MakeCheck(func(t *rapid.T) { //nolint:paralleltest
+		// keyFn is how [rapid] determines that values are distinct.
+		//
+		// We do this by calling [fmt.Stringer.String] on the normalized form of v.
+		keyFn := func(v r.PropertyValue) string { return normalize(v).String() }
+		values := rapid.SliceOfNDistinct(
+			rresource.PropertyValue(5), 2, 2, keyFn,
+		).Draw(t, "distinct")
+		assert.False(t, putil.DeepEquals(values[0], values[1]))
+	}))
+
+	t.Run("nested-outputs", func(t *testing.T) {
+		t.Parallel()
+
+		v1 := r.NewProperty(r.Output{
+			Element: r.NewProperty(r.Output{
+				Element: r.PropertyValue{V: interface{}(nil)},
+				Known:   false,
+				Secret:  false,
+				Dependencies: []urn.URN{
+					"",
+					"&\n[?", "\x7f=&\u202c\x7fᾩ:AȺ~",
+					"!aAὂ̥\ue007~a\x01?۵%",
+					"*\"\u2005\ue005-a=\v\u2008䍨~ᶞ٣_",
+				},
+			}),
+			Known:  true,
+			Secret: true,
+			Dependencies: []urn.URN{
+				"",
+				"A#@\u008b%\x00$\u202e\U000e006a|ᛮ<:ፘ.᭴ो〦\U000fd7da!𞥋\v%\x7fڌ֝[A{ॊⅣ\nA1|_\u3000%a",
+				"%",
+			},
+		})
+		v2 := r.NewProperty(r.Output{
+			Element: r.PropertyValue{V: interface{}(nil)},
+			Known:   false,
+			Secret:  true,
+			Dependencies: []urn.URN{
+				"",
+				"̿A#꙲ .\u2029\u1680~;,*\ue000֍\ue001º`a貦",
+				"_¦?!",
+				"\u2007�",
+				";\U000e003e\r𞥋\\𞓶\x02٦Lj$=1𝛜ᾫ?",
+				"{Aັ\\Dž",
+				"̆aLjⅺ*~",
+			},
+		})
+
+		assert.True(t, putil.DeepEquals(v1, v2))
+	})
+
+	t.Run("folding-secret-computed", func(t *testing.T) {
+		t.Parallel()
+
+		assert.True(t, putil.DeepEquals(
+			r.MakeComputed(r.MakeSecret(r.NewStringProperty("hi"))),
+			r.MakeSecret(r.MakeComputed(r.NewStringProperty("hi")))))
+		assert.False(t, putil.DeepEquals(
+			r.MakeSecret(r.NewStringProperty("hi")),
+			r.MakeComputed(r.NewStringProperty("hi"))))
+	})
+}
+
+func normalize(p r.PropertyValue) r.PropertyValue {
+	return r.ToResourcePropertyValue(r.FromResourcePropertyValue(p))
+}
diff --git a/putil/putil_test.go b/putil/putil_test.go
deleted file mode 100644
index c13eae0..0000000
--- a/putil/putil_test.go
+++ /dev/null
@@ -1,53 +0,0 @@
-// Copyright 2024, Pulumi Corporation.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package putil_test
-
-import (
-	"testing"
-
-	"github.com/pulumi/pulumi-go-provider/internal/putil"
-	rresource "github.com/pulumi/pulumi-go-provider/internal/rapid/resource"
-	r "github.com/pulumi/pulumi/sdk/v3/go/common/resource"
-	"github.com/stretchr/testify/assert"
-	"pgregory.net/rapid"
-)
-
-func TestRapidDeepEqual(t *testing.T) {
-	t.Parallel()
-	// Check that a value always equals itself
-	rapid.Check(t, func(t *rapid.T) {
-		value := rresource.PropertyValue(5).Draw(t, "value")
-
-		assert.True(t, putil.DeepEquals(value, value))
-	})
-
-	// Check that "distinct" values never equal themselves.
-	rapid.Check(t, func(t *rapid.T) {
-		values := rapid.SliceOfNDistinct(rresource.PropertyValue(5), 2, 2,
-			func(v r.PropertyValue) string {
-				return v.String()
-			}).Draw(t, "distinct")
-		assert.False(t, putil.DeepEquals(values[0], values[1]))
-	})
-
-	t.Run("folding", func(t *testing.T) {
-		assert.True(t, putil.DeepEquals(
-			r.MakeComputed(r.MakeSecret(r.NewStringProperty("hi"))),
-			r.MakeSecret(r.MakeComputed(r.NewStringProperty("hi")))))
-		assert.False(t, putil.DeepEquals(
-			r.MakeSecret(r.NewStringProperty("hi")),
-			r.MakeComputed(r.NewStringProperty("hi"))))
-	})
-}