com.facebook.buck.cxx.CxxWriteArgsToFileStep.java Source code

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Here is the source code for com.facebook.buck.cxx.CxxWriteArgsToFileStep.java

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/*
 * Copyright 2016-present Facebook, Inc.
 *
 * 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.facebook.buck.cxx;

import com.facebook.buck.io.MoreFiles;
import com.facebook.buck.rules.args.Arg;
import com.facebook.buck.rules.args.FileListableLinkerInputArg;
import com.facebook.buck.rules.args.SourcePathArg;
import com.facebook.buck.step.ExecutionContext;
import com.facebook.buck.step.Step;
import com.facebook.buck.step.StepExecutionResult;
import com.facebook.buck.util.MoreCollectors;
import com.google.common.base.Function;
import com.google.common.collect.ImmutableCollection;
import com.google.common.collect.ImmutableList;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.Optional;

/**
 * This step takes a list of args, stringify, escape them (if {@link #escaper} is present), and
 * finally store to a file {@link #argFilePath}.
 */
public class CxxWriteArgsToFileStep implements Step {

    private final Path argFilePath;
    private final ImmutableList<Arg> args;
    private final Optional<Function<String, String>> escaper;
    private final Path currentCellPath;

    CxxWriteArgsToFileStep(Path argFilePath, ImmutableList<Arg> args, Optional<Function<String, String>> escaper,
            Path currentCellPath) {
        this.argFilePath = argFilePath;
        this.args = args;
        this.escaper = escaper;
        this.currentCellPath = currentCellPath;
    }

    private void createArgFile() throws IOException {
        if (Files.notExists(argFilePath.getParent())) {
            Files.createDirectories(argFilePath.getParent());
        }
        ImmutableList<String> argFileContents = stringify(args, currentCellPath);
        if (escaper.isPresent()) {
            argFileContents = argFileContents.stream().map(escaper.get()::apply)
                    .collect(MoreCollectors.toImmutableList());
        }
        MoreFiles.writeLinesToFile(argFileContents, argFilePath);
    }

    static ImmutableList<String> stringify(ImmutableCollection<Arg> args, Path currentCellPath) {
        ImmutableList.Builder<String> builder = ImmutableList.builder();
        for (Arg arg : args) {
            if (arg instanceof FileListableLinkerInputArg) {
                ((FileListableLinkerInputArg) arg).appendToCommandLineRel(builder, currentCellPath);
            } else if (arg instanceof SourcePathArg) {
                ((SourcePathArg) arg).appendToCommandLineRel(builder, currentCellPath);
            } else {
                arg.appendToCommandLine(builder);
            }
        }
        return builder.build();
    }

    @Override
    public StepExecutionResult execute(ExecutionContext context) throws IOException, InterruptedException {
        createArgFile();
        return StepExecutionResult.SUCCESS;
    }

    @Override
    public String getShortName() {
        return "write args to file";
    }

    @Override
    public String getDescription(ExecutionContext context) {
        return "Write list of args to file, use string escape if provided.";
    }
}