cel-expr · copybara-service · Sep 16, 2026 · Sep 16, 2026
diff --git a/protobuf/src/main/java/dev/cel/protobuf/CelLiteDescriptor.java b/protobuf/src/main/java/dev/cel/protobuf/CelLiteDescriptor.java
@@ -18,6 +18,7 @@
 
 import com.google.errorprone.annotations.Immutable;
 import com.google.protobuf.MessageLite;
+import com.google.protobuf.WireFormat;
 import dev.cel.common.annotations.Internal;
 import java.util.Collections;
 import java.util.HashMap;
@@ -184,24 +185,95 @@ public enum JavaType {
      * <p>This is exactly the same as com.google.protobuf.Descriptors#Type
      */
     public enum Type {
-      DOUBLE,
-      FLOAT,
-      INT64,
-      UINT64,
-      INT32,
-      FIXED64,
-      FIXED32,
-      BOOL,
-      STRING,
-      GROUP,
-      MESSAGE,
-      BYTES,
-      UINT32,
-      ENUM,
-      SFIXED32,
-      SFIXED64,
-      SINT32,
-      SINT64
+      DOUBLE(1, WireFormat.FieldType.DOUBLE),
+      FLOAT(2, WireFormat.FieldType.FLOAT),
+      INT64(3, WireFormat.FieldType.INT64),
+      UINT64(4, WireFormat.FieldType.UINT64),
+      INT32(5, WireFormat.FieldType.INT32),
+      FIXED64(6, WireFormat.FieldType.FIXED64),
+      FIXED32(7, WireFormat.FieldType.FIXED32),
+      BOOL(8, WireFormat.FieldType.BOOL),
+      STRING(9, WireFormat.FieldType.STRING),
+      GROUP(10, WireFormat.FieldType.GROUP),
+      MESSAGE(11, WireFormat.FieldType.MESSAGE),
+      BYTES(12, WireFormat.FieldType.BYTES),
+      UINT32(13, WireFormat.FieldType.UINT32),
+      ENUM(14, WireFormat.FieldType.ENUM),
+      SFIXED32(15, WireFormat.FieldType.SFIXED32),
+      SFIXED64(16, WireFormat.FieldType.SFIXED64),
+      SINT32(17, WireFormat.FieldType.SINT32),
+      SINT64(18, WireFormat.FieldType.SINT64);
+
+      private final int number;
+      private final WireFormat.FieldType wireFormatFieldType;
+
+      /** Gets the type number corresponding to {@code FieldDescriptorProto.Type#getNumber()}. */
+      public int getNumber() {
+        return number;
+      }
+
+      /** Converts this type to the corresponding {@link WireFormat.FieldType}. */
+      public WireFormat.FieldType toWireFormatFieldType() {
+        return wireFormatFieldType;
+      }
+
+      /**
+       * Returns the {@link Type} for the specified protobuf type number.
+       *
+       * @throws IllegalArgumentException if the number does not correspond to a valid protobuf
+       *     type.
+       */
+      public static Type forNumber(int number) {
+        switch (number) {
+          case 1:
+            return DOUBLE;
+          case 2:
+            return FLOAT;
+          case 3:
+            return INT64;
+          case 4:
+            return UINT64;
+          case 5:
+            return INT32;
+          case 6:
+            return FIXED64;
+          case 7:
+            return FIXED32;
+          case 8:
+            return BOOL;
+          case 9:
+            return STRING;
+          case 10:
+            return GROUP;
+          case 11:
+            return MESSAGE;
+          case 12:
+            return BYTES;
+          case 13:
+            return UINT32;
+          case 14:
+            return ENUM;
+          case 15:
+            return SFIXED32;
+          case 16:
+            return SFIXED64;
+          case 17:
+            return SINT32;
+          case 18:
+            return SINT64;
+          default:
+            throw new IllegalArgumentException("Unsupported proto type code: " + number);
+        }
+      }
+
+      private Type(int number, WireFormat.FieldType wireFormatFieldType) {
+        this.number = number;
+        this.wireFormatFieldType = Objects.requireNonNull(wireFormatFieldType);
+      }
+    }
+
+    public int getFieldNumber() {
+      return fieldNumber;
     }
 
     public String getFieldName() {
@@ -269,9 +341,9 @@ public FieldLiteDescriptor(
         String fieldProtoTypeName) {
       this.fieldNumber = fieldNumber;
       this.fieldName = Objects.requireNonNull(fieldName);
-      this.javaType = javaType;
-      this.encodingType = encodingType;
-      this.protoFieldType = protoFieldType;
+      this.javaType = Objects.requireNonNull(javaType);
+      this.encodingType = Objects.requireNonNull(encodingType);
+      this.protoFieldType = Objects.requireNonNull(protoFieldType);
       this.isPacked = isPacked;
       this.fieldProtoTypeName = Objects.requireNonNull(fieldProtoTypeName);
     }

diff --git a/protobuf/src/test/java/dev/cel/protobuf/BUILD.bazel b/protobuf/src/test/java/dev/cel/protobuf/BUILD.bazel
@@ -16,6 +16,7 @@ java_test(
         "@cel_spec//proto/cel/expr/conformance/proto3:test_all_types_java_proto_lite",
         "@maven//:com_google_testparameterinjector_test_parameter_injector",
         "@maven//:junit_junit",
+        "@maven_android//:com_google_protobuf_protobuf_javalite",
     ],
 )
 

diff --git a/protobuf/src/test/java/dev/cel/protobuf/CelLiteDescriptorTest.java b/protobuf/src/test/java/dev/cel/protobuf/CelLiteDescriptorTest.java
@@ -15,7 +15,10 @@
 package dev.cel.protobuf;
 
 import static com.google.common.truth.Truth.assertThat;
+import static org.junit.Assert.assertThrows;
 
+import com.google.protobuf.WireFormat;
+import com.google.testing.junit.testparameterinjector.TestParameter;
 import com.google.testing.junit.testparameterinjector.TestParameterInjector;
 import dev.cel.expr.conformance.proto3.TestAllTypesCelLiteDescriptor;
 import dev.cel.protobuf.CelLiteDescriptor.FieldLiteDescriptor;
@@ -146,4 +149,96 @@ public void fieldDescriptor_nestedMessage_fullyQualifiedNames() {
     assertThat(fieldLiteDescriptor.getFieldProtoTypeName())
         .isEqualTo("cel.expr.conformance.proto3.TestAllTypes.NestedMessage");
   }
+
+  private enum ProtoFieldTypeTestCase {
+    DOUBLE(FieldLiteDescriptor.Type.DOUBLE, 1, WireFormat.FieldType.DOUBLE),
+    FLOAT(FieldLiteDescriptor.Type.FLOAT, 2, WireFormat.FieldType.FLOAT),
+    INT64(FieldLiteDescriptor.Type.INT64, 3, WireFormat.FieldType.INT64),
+    UINT64(FieldLiteDescriptor.Type.UINT64, 4, WireFormat.FieldType.UINT64),
+    INT32(FieldLiteDescriptor.Type.INT32, 5, WireFormat.FieldType.INT32),
+    FIXED64(FieldLiteDescriptor.Type.FIXED64, 6, WireFormat.FieldType.FIXED64),
+    FIXED32(FieldLiteDescriptor.Type.FIXED32, 7, WireFormat.FieldType.FIXED32),
+    BOOL(FieldLiteDescriptor.Type.BOOL, 8, WireFormat.FieldType.BOOL),
+    STRING(FieldLiteDescriptor.Type.STRING, 9, WireFormat.FieldType.STRING),
+    GROUP(FieldLiteDescriptor.Type.GROUP, 10, WireFormat.FieldType.GROUP),
+    MESSAGE(FieldLiteDescriptor.Type.MESSAGE, 11, WireFormat.FieldType.MESSAGE),
+    BYTES(FieldLiteDescriptor.Type.BYTES, 12, WireFormat.FieldType.BYTES),
+    UINT32(FieldLiteDescriptor.Type.UINT32, 13, WireFormat.FieldType.UINT32),
+    ENUM(FieldLiteDescriptor.Type.ENUM, 14, WireFormat.FieldType.ENUM),
+    SFIXED32(FieldLiteDescriptor.Type.SFIXED32, 15, WireFormat.FieldType.SFIXED32),
+    SFIXED64(FieldLiteDescriptor.Type.SFIXED64, 16, WireFormat.FieldType.SFIXED64),
+    SINT32(FieldLiteDescriptor.Type.SINT32, 17, WireFormat.FieldType.SINT32),
+    SINT64(FieldLiteDescriptor.Type.SINT64, 18, WireFormat.FieldType.SINT64);
+
+    private final FieldLiteDescriptor.Type type;
+    private final int expectedNumber;
+    private final WireFormat.FieldType expectedWireType;
+
+    ProtoFieldTypeTestCase(
+        FieldLiteDescriptor.Type type, int expectedNumber, WireFormat.FieldType expectedWireType) {
+      this.type = type;
+      this.expectedNumber = expectedNumber;
+      this.expectedWireType = expectedWireType;
+    }
+  }
+
+  @Test
+  public void protoFieldType_numbersAndWireTypes(@TestParameter ProtoFieldTypeTestCase testCase) {
+    assertThat(testCase.type.getNumber()).isEqualTo(testCase.expectedNumber);
+    assertThat(testCase.type.toWireFormatFieldType()).isEqualTo(testCase.expectedWireType);
+  }
+
+  @Test
+  public void protoFieldType_forNumber_roundTripAllTypes(
+      @TestParameter FieldLiteDescriptor.Type type) {
+    assertThat(FieldLiteDescriptor.Type.forNumber(type.getNumber())).isEqualTo(type);
+  }
+
+  @Test
+  public void protoFieldType_forNumber_outOfRange_throws(
+      @TestParameter({"-2147483648", "-1", "0", "19", "100", "2147483647"}) int invalidNumber) {
+    IllegalArgumentException e =
+        assertThrows(
+            IllegalArgumentException.class,
+            () -> FieldLiteDescriptor.Type.forNumber(invalidNumber));
+
+    assertThat(e).hasMessageThat().isEqualTo("Unsupported proto type code: " + invalidNumber);
+  }
+
+  @Test
+  public void fieldLiteDescriptor_nullParameters_throws() {
+    assertThrows(
+        NullPointerException.class,
+        () ->
+            new FieldLiteDescriptor(
+                1,
+                "field",
+                null,
+                EncodingType.SINGULAR,
+                FieldLiteDescriptor.Type.INT32,
+                false,
+                ""));
+    assertThrows(
+        NullPointerException.class,
+        () ->
+            new FieldLiteDescriptor(
+                1,
+                "field",
+                FieldLiteDescriptor.JavaType.INT,
+                null,
+                FieldLiteDescriptor.Type.INT32,
+                false,
+                ""));
+    assertThrows(
+        NullPointerException.class,
+        () ->
+            new FieldLiteDescriptor(
+                1,
+                "field",
+                FieldLiteDescriptor.JavaType.INT,
+                EncodingType.SINGULAR,
+                null,
+                false,
+                ""));
+  }
 }