Add support for context expr to CEL test case input

testing/src/main/java/dev/cel/testing/utils/ExprValueUtils.java

@@ -33,6 +33,7 @@
 import dev.cel.common.types.CelType;
 import dev.cel.common.types.ListType;
 import dev.cel.common.types.MapType;
+import dev.cel.common.types.OptionalType;
 import dev.cel.common.types.SimpleType;
 import dev.cel.common.types.TypeType;
 import java.io.IOException;
@@ -144,6 +145,9 @@ public static ExprValue toExprValue(Object object, CelType type) throws Exceptio
    */
   @SuppressWarnings("unchecked")
   public static Value toValue(Object object, CelType type) throws Exception {
+    if (!(object instanceof Optional) && type instanceof OptionalType) {
+      return toValue(object, type.parameters().get(0));
+    }
     if (object == null) {
       object = NullValue.NULL_VALUE;
     }
@@ -230,7 +234,11 @@ public static Value toValue(Object object, CelType type) throws Exception {
     }
 
     if (object instanceof Optional) {
-      return toValue(((Optional<?>) object).get(), type);
+      // TODO: Remove this once the ExprValue Native representation is added.
+      if (!((Optional<?>) object).isPresent()) {
+        return Value.getDefaultInstance();
+      }
+      return toValue(((Optional<?>) object).get(), type.parameters().get(0));
     }
 
     throw new IllegalArgumentException(

testing/src/test/resources/policy/context_pb/config.yaml

@@ -0,0 +1,19 @@
+# Copyright 2025 Google LLC
+#
+# 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
+#
+#    https://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.
+
+name: "context_pb"
+container: "cel.expr.conformance.proto3"
+extensions:
+  - name: "strings"
+    version: "latest"

testing/src/test/resources/policy/context_pb/policy.yaml

@@ -0,0 +1,25 @@
+# Copyright 2025 Google LLC
+#
+# 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
+#
+#    https://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.
+
+name: "context_pb"
+rule:
+  match:
+    - condition: >
+        single_int32 > TestAllTypes{single_int64: 10}.single_int64
+      output: |
+        ["invalid spec, got single_int32=" , single_int32 , ", wanted <= 10"].join()
+    - condition: >
+        standalone_enum == TestAllTypes.NestedEnum.BAR
+      output: |
+        "invalid spec, no nested enums may refer to BAR"

testing/src/test/resources/policy/context_pb/tests.yaml

@@ -0,0 +1,35 @@
+# Copyright 2025 Google LLC
+#
+# 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
+#
+#    https://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.
+
+name: "context_pb_cel_tests"
+description: "Protobuf input tests"
+sections:
+  - name: "valid"
+    description: "Valid context_expr"
+    tests:
+     - name: "good spec"
+       description: "good spec"
+       context_expr:
+             "TestAllTypes{single_int32: 10}"
+       output:
+        expr: "optional.none()"
+  - name: "invalid"
+    description: "Invalid context_expr"
+    tests:
+     - name: "bad spec"
+       description: "bad spec"
+       context_expr:
+             "TestAllTypes{single_int32: 11}"
+       output:
+         value: "invalid spec, got single_int32=11, wanted <= 10"