1 files changed, 93 insertions, 0 deletions
diff --git a/src/main/java/com/google/devtools/build/lib/runtime/commands/ProjectFileSupport.java b/src/main/java/com/google/devtools/build/lib/runtime/commands/ProjectFileSupport.java
new file mode 100644
index 0000000000..2e5faf6ca8
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/runtime/commands/ProjectFileSupport.java
@@ -0,0 +1,93 @@
+// Copyright 2014 Google Inc. 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.lib.runtime.commands;
+
+import com.google.devtools.build.lib.events.Event;
+import com.google.devtools.build.lib.pkgcache.PackageCacheOptions;
+import com.google.devtools.build.lib.pkgcache.PathPackageLocator;
+import com.google.devtools.build.lib.runtime.BlazeCommand;
+import com.google.devtools.build.lib.runtime.BlazeRuntime;
+import com.google.devtools.build.lib.runtime.CommonCommandOptions;
+import com.google.devtools.build.lib.runtime.ProjectFile;
+import com.google.devtools.build.lib.util.AbruptExitException;
+import com.google.devtools.build.lib.util.ExitCode;
+import com.google.devtools.build.lib.vfs.Path;
+import com.google.devtools.build.lib.vfs.PathFragment;
+import com.google.devtools.common.options.OptionPriority;
+import com.google.devtools.common.options.OptionsParser;
+import com.google.devtools.common.options.OptionsParsingException;
+import com.google.devtools.common.options.OptionsProvider;
+
+import java.util.List;
+
+/**
+ * Provides support for implementations for {@link BlazeCommand} to work with {@link ProjectFile}.
+ */
+public final class ProjectFileSupport {
+  static final String PROJECT_FILE_PREFIX = "+";
+  
+  private ProjectFileSupport() {}
+
+  /**
+   * Reads any project files specified on the command line and updates the options parser
+   * accordingly. If project files cannot be read or if they contain unparsable options, or if they
+   * are not enabled, then it throws an exception instead.
+   */
+  public static void handleProjectFiles(BlazeRuntime runtime, OptionsParser optionsParser,
+      String command) throws AbruptExitException {
+    List<String> targets = optionsParser.getResidue();
+    ProjectFile.Provider projectFileProvider = runtime.getProjectFileProvider();
+    if (projectFileProvider != null && targets.size() > 0
+        && targets.get(0).startsWith(PROJECT_FILE_PREFIX)) {
+      if (targets.size() > 1) {
+        throw new AbruptExitException("Cannot handle more than one +<file> argument yet",
+            ExitCode.COMMAND_LINE_ERROR);
+      }
+      if (!optionsParser.getOptions(CommonCommandOptions.class).allowProjectFiles) {
+        throw new AbruptExitException("project file support is not enabled",
+            ExitCode.COMMAND_LINE_ERROR);
+      }
+      // TODO(bazel-team): This is currently treated as a path relative to the workspace - if the
+      // cwd is a subdirectory of the workspace, that will be surprising, and we should interpret it
+      // relative to the cwd instead.
+      PathFragment projectFilePath = new PathFragment(targets.get(0).substring(1));
+      List<Path> packagePath = PathPackageLocator.create(
+          optionsParser.getOptions(PackageCacheOptions.class).packagePath, runtime.getReporter(),
+          runtime.getWorkspace(), runtime.getWorkingDirectory()).getPathEntries();
+      ProjectFile projectFile = projectFileProvider.getProjectFile(packagePath, projectFilePath);
+      runtime.getReporter().handle(Event.info("Using " + projectFile.getName()));
+
+      try {
+        optionsParser.parse(
+            OptionPriority.RC_FILE, projectFile.getName(), projectFile.getCommandLineFor(command));
+      } catch (OptionsParsingException e) {
+        throw new AbruptExitException(e.getMessage(), ExitCode.COMMAND_LINE_ERROR);
+      }
+    }
+  }
+
+  /**
+   * Returns a list of targets from the options residue. If a project file is supplied as the first
+   * argument, it will be ignored, on the assumption that handleProjectFiles() has been called to
+   * process it.
+   */
+  public static List<String> getTargets(BlazeRuntime runtime, OptionsProvider options) {
+    List<String> targets = options.getResidue();
+    if (runtime.getProjectFileProvider() != null && targets.size() > 0
+        && targets.get(0).startsWith(PROJECT_FILE_PREFIX)) {
+      return targets.subList(1, targets.size());
+    }
+    return targets;
+  }
+}