src/main/java/com/google/devtools/build/skydoc/fakebuildapi/FakeProviderApi.java

// Copyright 2018 The Bazel Authors. All rights reserved.
//
// 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 com.google.devtools.build.skydoc.fakebuildapi;

import com.google.devtools.build.lib.skylarkbuildapi.ProviderApi;
import com.google.devtools.build.lib.skylarkinterface.SkylarkPrinter;
import com.google.devtools.build.lib.syntax.BaseFunction;
import com.google.devtools.build.lib.syntax.Environment;
import com.google.devtools.build.lib.syntax.EvalException;
import com.google.devtools.build.lib.syntax.FuncallExpression;
import com.google.devtools.build.lib.syntax.FunctionSignature;
import javax.annotation.Nullable;

/**
 * Fake implementation of {@link ProviderApi}. This fake is a subclass of {@link BaseFunction},
 * as providers are themselves callable.
 */
public class FakeProviderApi extends BaseFunction implements ProviderApi {

  /**
   * Each fake is constructed with a unique name, controlled by this counter being the name suffix.
   */
  private static int idCounter = 0;

  public FakeProviderApi() {
    super("ProviderIdentifier" + idCounter++,
        FunctionSignature.WithValues.create(FunctionSignature.KWARGS));
  }

  @Override
  protected Object call(Object[] args, @Nullable FuncallExpression ast, Environment env)
      throws EvalException, InterruptedException {
    return new FakeStructApi();
  }

  @Override
  public void repr(SkylarkPrinter printer) {}

  @Override
  public boolean equals(@Nullable Object other) {
    // Use exact object matching.
    return this == other;
  }
}