EvalIndex.java

// Copyright 2026 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.

package dev.cel.runtime.planner;

import static dev.cel.runtime.planner.EvalHelpers.evalNonstrictly;
import static dev.cel.runtime.planner.EvalHelpers.evalStrictly;

import com.google.errorprone.annotations.Immutable;
import dev.cel.common.ast.CelExpr;
import dev.cel.common.values.CelValueConverter;
import dev.cel.runtime.AccumulatedUnknowns;
import dev.cel.runtime.CelEvaluationException;
import dev.cel.runtime.CelResolvedOverload;
import dev.cel.runtime.GlobalResolver;

@Immutable
final class EvalIndex extends PlannedInterpretable {

  private final String functionName;
  private final CelResolvedOverload resolvedOverload;
  private final PlannedInterpretable target;
  private final PlannedInterpretable index;
  private final CelValueConverter celValueConverter;

  @Override
  Object evalInternal(GlobalResolver resolver, ExecutionFrame frame) throws CelEvaluationException {
    boolean isStrict = resolvedOverload.isStrict();
    Object targetVal =
        isStrict ? evalStrictly(target, resolver, frame) : evalNonstrictly(target, resolver, frame);
    Object indexVal =
        isStrict ? evalStrictly(index, resolver, frame) : evalNonstrictly(index, resolver, frame);

    if (isStrict) {
      AccumulatedUnknowns unknowns = AccumulatedUnknowns.maybeMerge(null, targetVal);
      unknowns = AccumulatedUnknowns.maybeMerge(unknowns, indexVal);
      if (unknowns != null) {
        return unknowns;
      }
    }

    return EvalHelpers.dispatch(
        functionName, resolvedOverload, celValueConverter, targetVal, indexVal);
  }

  static EvalIndex create(
      CelExpr expr,
      String functionName,
      CelResolvedOverload resolvedOverload,
      PlannedInterpretable target,
      PlannedInterpretable index,
      CelValueConverter celValueConverter) {
    return new EvalIndex(expr, functionName, resolvedOverload, target, index, celValueConverter);
  }

  private EvalIndex(
      CelExpr expr,
      String functionName,
      CelResolvedOverload resolvedOverload,
      PlannedInterpretable target,
      PlannedInterpretable index,
      CelValueConverter celValueConverter) {
    super(expr);
    this.functionName = functionName;
    this.resolvedOverload = resolvedOverload;
    this.target = target;
    this.index = index;
    this.celValueConverter = celValueConverter;
  }
}