feat: add FailureBehavior enum to Cast immutable (#115)

Author: gatesn

core/src/main/java/io/substrait/expression/Expression.java

@@ -532,6 +532,8 @@ abstract static class Cast implements Expression {
 
     public abstract Expression input();
 
+    public abstract FailureBehavior failureBehavior();
+
     public Type getType() {
       return type();
     }
@@ -770,7 +772,7 @@ public static AggregationPhase fromProto(io.substrait.proto.AggregationPhase pro
     }
   }
 
-  public enum SortDirection {
+  enum SortDirection {
     ASC_NULLS_FIRST(io.substrait.proto.SortField.SortDirection.SORT_DIRECTION_ASC_NULLS_FIRST),
     ASC_NULLS_LAST(io.substrait.proto.SortField.SortDirection.SORT_DIRECTION_ASC_NULLS_LAST),
     DESC_NULLS_FIRST(io.substrait.proto.SortField.SortDirection.SORT_DIRECTION_DESC_NULLS_FIRST),
@@ -797,4 +799,32 @@ public static SortDirection fromProto(io.substrait.proto.SortField.SortDirection
       throw new IllegalArgumentException("Unknown type: " + proto);
     }
   }
+
+  enum FailureBehavior {
+    UNSPECIFIED(io.substrait.proto.Expression.Cast.FailureBehavior.FAILURE_BEHAVIOR_UNSPECIFIED),
+    RETURN_NULL(io.substrait.proto.Expression.Cast.FailureBehavior.FAILURE_BEHAVIOR_RETURN_NULL),
+    THROW_EXCEPTION(
+        io.substrait.proto.Expression.Cast.FailureBehavior.FAILURE_BEHAVIOR_THROW_EXCEPTION);
+
+    private final io.substrait.proto.Expression.Cast.FailureBehavior proto;
+
+    FailureBehavior(io.substrait.proto.Expression.Cast.FailureBehavior proto) {
+      this.proto = proto;
+    }
+
+    public io.substrait.proto.Expression.Cast.FailureBehavior toProto() {
+      return proto;
+    }
+
+    public static FailureBehavior fromProto(
+        io.substrait.proto.Expression.Cast.FailureBehavior proto) {
+      for (var v : values()) {
+        if (v.proto == proto) {
+          return v;
+        }
+      }
+
+      throw new IllegalArgumentException("Unknown type: " + proto);
+    }
+  }
 }

core/src/main/java/io/substrait/expression/ExpressionCreator.java

@@ -9,7 +9,9 @@
 import java.time.Instant;
 import java.time.LocalDateTime;
 import java.time.ZoneOffset;
-import java.util.*;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
 import java.util.concurrent.TimeUnit;
 
 public class ExpressionCreator {
@@ -341,7 +343,16 @@ public static WindowFunctionInvocation windowFunction(
   }
 
   public static Expression cast(Type type, Expression expression) {
-    return Expression.Cast.builder().type(type).input(expression).build();
+    return cast(type, expression, Expression.FailureBehavior.UNSPECIFIED);
+  }
+
+  public static Expression cast(
+      Type type, Expression expression, Expression.FailureBehavior failureBehavior) {
+    return Expression.Cast.builder()
+        .type(type)
+        .input(expression)
+        .failureBehavior(failureBehavior)
+        .build();
   }
 
   private static ByteString padLeftIfNeeded(byte[] value, int length) {

core/src/main/java/io/substrait/expression/proto/ExpressionProtoConverter.java

@@ -276,7 +276,8 @@ public Expression visit(io.substrait.expression.Expression.Cast expr) {
         .setCast(
             Expression.Cast.newBuilder()
                 .setInput(expr.input().accept(this))
-                .setType(expr.getType().accept(TypeProtoConverter.INSTANCE)))
+                .setType(expr.getType().accept(TypeProtoConverter.INSTANCE))
+                .setFailureBehavior(expr.failureBehavior().toProto()))
         .build();
   }
 

core/src/main/java/io/substrait/function/SimpleExtension.java

@@ -379,7 +379,7 @@ public abstract static class ScalarFunction {
 
     public abstract List<ScalarFunctionVariant> impls();
 
-    Stream<ScalarFunctionVariant> resolve(String uri) {
+    public Stream<ScalarFunctionVariant> resolve(String uri) {
       return impls().stream().map(f -> f.resolve(uri, name(), description()));
     }
   }