src/main/java/com/google/devtools/build/lib/analysis/SourceManifestAction.java - bazel - Git at Google

 // Copyright 2014 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.lib.analysis;

 import static com.google.common.collect.ImmutableList.toImmutableList;
 import static java.nio.charset.StandardCharsets.ISO_8859_1;
 import static java.nio.charset.StandardCharsets.UTF_8;

 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.collect.ImmutableList;
 import com.google.devtools.build.lib.actions.AbstractAction;
 import com.google.devtools.build.lib.actions.ActionExecutionContext;
 import com.google.devtools.build.lib.actions.ActionKeyContext;
 import com.google.devtools.build.lib.actions.ActionOwner;
 import com.google.devtools.build.lib.actions.Artifact;
 import com.google.devtools.build.lib.analysis.actions.AbstractFileWriteAction;
 import com.google.devtools.build.lib.analysis.actions.DeterministicWriter;
 import com.google.devtools.build.lib.analysis.starlark.UnresolvedSymlinkAction;
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.collect.nestedset.Order;
 import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
 import com.google.devtools.build.lib.events.EventHandler;
 import com.google.devtools.build.lib.util.Fingerprint;
 import com.google.devtools.build.lib.vfs.PathFragment;
 import java.io.BufferedWriter;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.io.OutputStreamWriter;
 import java.io.Writer;
 import java.util.ArrayList;
 import java.util.Comparator;
 import java.util.List;
 import java.util.Map;
 import javax.annotation.Nullable;

 /**
  * Creates a manifest file describing a symlink tree.
  *
  * <p>In addition to symlink trees (whose manifests are a tree position -> exec path map), this
  * action can also create manifest consisting of just exec paths for historical reasons.
  *
  * <p>This action carefully avoids building the manifest content in memory because it can be large.
  */
 @Immutable // if all ManifestWriter implementations are immutable
 public final class SourceManifestAction extends AbstractFileWriteAction
     implements AbstractFileWriteAction.FileContentsProvider {

   private static final String GUID = "07459553-a3d0-4d37-9d78-18ed942470f4";

   private static final Comparator<Map.Entry<PathFragment, Artifact>> ENTRY_COMPARATOR =
       (path1, path2) -> path1.getKey().getPathString().compareTo(path2.getKey().getPathString());
   private final Artifact repoMappingManifest;
   /**
    * Interface for defining manifest formatting and reporting specifics. Implementations must be
    * immutable.
    */
   @VisibleForTesting
   interface ManifestWriter {

     /**
      * Writes a single line of manifest output.
      *
      * @param manifestWriter the output stream
      * @param rootRelativePath path of an entry relative to the manifest's root
      * @param symlink (optional) symlink that resolves the above path
      */
     void writeEntry(
         Writer manifestWriter, PathFragment rootRelativePath, @Nullable Artifact symlink)
         throws IOException;

     /** Fulfills {@link com.google.devtools.build.lib.actions.AbstractAction#getMnemonic()} */
     String getMnemonic();

     /**
      * Fulfills {@link com.google.devtools.build.lib.actions.AbstractAction#getRawProgressMessage()}
      */
     String getRawProgressMessage();

     /**
      * Fulfills {@link AbstractFileWriteAction#isRemotable()}.
      *
      * @return
      */
     boolean isRemotable();

     /** Whether the manifest includes absolute paths to artifacts. */
     boolean emitsAbsolutePaths();
   }

   /** The strategy we use to write manifest entries. */
   private final ManifestWriter manifestWriter;

   /** The runfiles for which to create the symlink tree. */
   private final Runfiles runfiles;

   private final boolean remotableSourceManifestActions;

   private NestedSet<Artifact> symlinkArtifacts = null;

   /**
    * Creates a new AbstractSourceManifestAction instance using latin1 encoding to write the manifest
    * file and with a specified root path for manifest entries.
    *
    * @param manifestWriter the strategy to use to write manifest entries
    * @param owner the action owner
    * @param primaryOutput the file to which to write the manifest
    * @param runfiles runfiles
    */
   @VisibleForTesting
   SourceManifestAction(
       ManifestWriter manifestWriter, ActionOwner owner, Artifact primaryOutput, Runfiles runfiles) {
     this(manifestWriter, owner, primaryOutput, runfiles, null, false);
   }

   /**
    * Creates a new AbstractSourceManifestAction instance using latin1 encoding to write the manifest
    * file and with a specified root path for manifest entries.
    *
    * @param manifestWriter the strategy to use to write manifest entries
    * @param owner the action owner
    * @param primaryOutput the file to which to write the manifest
    * @param runfiles runfiles
    * @param repoMappingManifest the repository mapping manifest for runfiles
    */
   public SourceManifestAction(
       ManifestWriter manifestWriter,
       ActionOwner owner,
       Artifact primaryOutput,
       Runfiles runfiles,
       @Nullable Artifact repoMappingManifest,
       boolean remotableSourceManifestActions) {
     // The real set of inputs is computed in #getInputs().
     super(owner, NestedSetBuilder.emptySet(Order.STABLE_ORDER), primaryOutput, false);
     this.manifestWriter = manifestWriter;
     this.runfiles = runfiles;
     this.repoMappingManifest = repoMappingManifest;
     this.remotableSourceManifestActions = remotableSourceManifestActions;
   }

   /**
    * The manifest entry for a symlink artifact should contain the target of the symlink rather than
    * its exec path. Reading the symlink target requires that the symlink artifact is declared as an
    * input of this action. Since declaring all runfiles as inputs of the manifest action would
    * unnecessarily delay its execution, this action exceptionally overrides {@link
    * AbstractAction#getInputs()} and filters out the non-symlink runfiles by flattening the nested
    * set of runfiles. Benchmarks confirmed that this does not regress performance.
    *
    * <p>Alternatives considered:
    *
    * <ul>
    *   <li>Having users separate normal artifacts from symlink artifacts during analysis: Makes it
    *       impossible to pass symlink artifacts to rules that aren't aware of them and requires the
    *       use of custom providers to pass symlinks to stage as inputs to actions.
    *   <li>Reaching into {@link ActionExecutionContext} to look up the generating action of symlink
    *       artifacts and retrieving the target from {@link UnresolvedSymlinkAction}: This would not
    *       work for symlinks whose target is determined in the execution phase.
    *   <li>Input discovery: Complex and error-prone in general and conceptually not necessary here -
    *       we already know what the inputs will be during analysis, we just want to delay the
    *       required computations.
    * </ul>
    */
   @Override
   public synchronized NestedSet<Artifact> getInputs() {
     if (symlinkArtifacts == null) {
       ImmutableList<Artifact> symlinks =
           runfiles.getArtifacts().toList().stream()
               .filter(Artifact::isSymlink)
               .collect(toImmutableList());
       symlinkArtifacts = NestedSetBuilder.wrap(Order.STABLE_ORDER, symlinks);
     }
     return symlinkArtifacts;
   }

   @VisibleForTesting
   public void writeOutputFile(OutputStream out, @Nullable EventHandler eventHandler)
       throws IOException {
     writeFile(
         out,
         runfiles.getRunfilesInputs(eventHandler, getOwner().getLocation(), repoMappingManifest));
   }

   /**
    * Get the contents of a file internally using an in memory output stream.
    *
    * @return returns the file contents as a string.
    */
   @Override
   public String getFileContents(@Nullable EventHandler eventHandler) throws IOException {
     ByteArrayOutputStream stream = new ByteArrayOutputStream();
     writeOutputFile(stream, eventHandler);
     return stream.toString(UTF_8);
   }

   @Override
   public String getStarlarkContent() throws IOException {
     return getFileContents(null);
   }

   @Override
   public DeterministicWriter newDeterministicWriter(ActionExecutionContext ctx) {
     final Map<PathFragment, Artifact> runfilesInputs =
         runfiles.getRunfilesInputs(
             ctx.getEventHandler(), getOwner().getLocation(), repoMappingManifest);
     return out -> writeFile(out, runfilesInputs);
   }

   @Override
   public boolean isRemotable() {
     return remotableSourceManifestActions || manifestWriter.isRemotable();
   }

   /**
    * Sort the entries in both the normal and root manifests and write the output file.
    *
    * @param out is the message stream to write errors to.
    * @param output The actual mapping of the output manifest.
    * @throws IOException
    */
   private void writeFile(OutputStream out, Map<PathFragment, Artifact> output) throws IOException {
     Writer manifestFile = new BufferedWriter(new OutputStreamWriter(out, ISO_8859_1));
     List<Map.Entry<PathFragment, Artifact>> sortedManifest = new ArrayList<>(output.entrySet());
     sortedManifest.sort(ENTRY_COMPARATOR);
     for (Map.Entry<PathFragment, Artifact> line : sortedManifest) {
       manifestWriter.writeEntry(manifestFile, line.getKey(), line.getValue());
     }

     manifestFile.flush();
   }

   @Override
   public String getMnemonic() {
     return manifestWriter.getMnemonic();
   }

   @Override
   protected String getRawProgressMessage() {
     return manifestWriter.getRawProgressMessage() + " for " + getOwner().getLabel();
   }

   @Override
   protected void computeKey(
       ActionKeyContext actionKeyContext,
       @Nullable Artifact.ArtifactExpander artifactExpander,
       Fingerprint fp) {
     fp.addString(GUID);
     fp.addBoolean(remotableSourceManifestActions);
     runfiles.fingerprint(actionKeyContext, fp, manifestWriter.emitsAbsolutePaths());
     fp.addBoolean(repoMappingManifest != null);
     if (repoMappingManifest != null) {
       fp.addPath(repoMappingManifest.getExecPath());
     }
   }

   @Override
   public String describeKey() {
     return String.format(
         "GUID: %s\nremotableSourceManifestActions: %s\nrunfiles: %s\n",
         GUID,
         remotableSourceManifestActions,
         runfiles.describeFingerprint(manifestWriter.emitsAbsolutePaths()));
   }

   /** Supported manifest writing strategies. */
   public enum ManifestType implements ManifestWriter {

     /**
      * Writes each line as:
      *
      * <p>[rootRelativePath] [resolvingSymlink]
      *
      * <p>This strategy is suitable for creating an input manifest to a source view tree. Its output
      * is a valid input to {@link com.google.devtools.build.lib.analysis.actions.SymlinkTreeAction}.
      */
     SOURCE_SYMLINKS {
       @Override
       public void writeEntry(Writer manifestWriter, PathFragment rootRelativePath, Artifact symlink)
           throws IOException {
         manifestWriter.append(rootRelativePath.getPathString());
         // This trailing whitespace is REQUIRED to process the single entry line correctly.
         manifestWriter.append(' ');
         if (symlink != null) {
           if (symlink.isSymlink()) {
             manifestWriter.append(symlink.getPath().readSymbolicLink().getPathString());
           } else {
             manifestWriter.append(symlink.getPath().getPathString());
           }
         }
         manifestWriter.append('\n');
       }

       @Override
       public String getMnemonic() {
         return "SourceSymlinkManifest";
       }

       @Override
       public String getRawProgressMessage() {
         return "Creating source manifest";
       }

       @Override
       public boolean isRemotable() {
         // There is little gain to remoting these, since they include absolute path names inline.
         return false;
       }

       @Override
       public boolean emitsAbsolutePaths() {
         return true;
       }
     },

     /**
      * Writes each line as:
      *
      * <p>[rootRelativePath]
      *
      * <p>This strategy is suitable for an input into a packaging system (notably .par) that
      * consumes a list of all source files but needs that list to be constant with respect to how
      * the user has their client laid out on local disk.
      */
     SOURCES_ONLY {
       @Override
       public void writeEntry(Writer manifestWriter, PathFragment rootRelativePath, Artifact symlink)
           throws IOException {
         manifestWriter.append(rootRelativePath.getPathString());
         manifestWriter.append('\n');
         manifestWriter.flush();
       }

       @Override
       public String getMnemonic() {
         return "PackagingSourcesManifest";
       }

       @Override
       public String getRawProgressMessage() {
         return "Creating file sources list";
       }

       @Override
       public boolean isRemotable() {
         // Source-only symlink manifest has root-relative paths and does not include absolute paths.
         return true;
       }

       @Override
       public boolean emitsAbsolutePaths() {
         return false;
       }
     }
   }
 }
	// Copyright 2014 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.lib.analysis;

	import static com.google.common.collect.ImmutableList.toImmutableList;
	import static java.nio.charset.StandardCharsets.ISO_8859_1;
	import static java.nio.charset.StandardCharsets.UTF_8;

	import com.google.common.annotations.VisibleForTesting;
	import com.google.common.collect.ImmutableList;
	import com.google.devtools.build.lib.actions.AbstractAction;
	import com.google.devtools.build.lib.actions.ActionExecutionContext;
	import com.google.devtools.build.lib.actions.ActionKeyContext;
	import com.google.devtools.build.lib.actions.ActionOwner;
	import com.google.devtools.build.lib.actions.Artifact;
	import com.google.devtools.build.lib.analysis.actions.AbstractFileWriteAction;
	import com.google.devtools.build.lib.analysis.actions.DeterministicWriter;
	import com.google.devtools.build.lib.analysis.starlark.UnresolvedSymlinkAction;
	import com.google.devtools.build.lib.collect.nestedset.NestedSet;
	import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
	import com.google.devtools.build.lib.collect.nestedset.Order;
	import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
	import com.google.devtools.build.lib.events.EventHandler;
	import com.google.devtools.build.lib.util.Fingerprint;
	import com.google.devtools.build.lib.vfs.PathFragment;
	import java.io.BufferedWriter;
	import java.io.ByteArrayOutputStream;
	import java.io.IOException;
	import java.io.OutputStream;
	import java.io.OutputStreamWriter;
	import java.io.Writer;
	import java.util.ArrayList;
	import java.util.Comparator;
	import java.util.List;
	import java.util.Map;
	import javax.annotation.Nullable;

	/**
	* Creates a manifest file describing a symlink tree.
	*
	* <p>In addition to symlink trees (whose manifests are a tree position -> exec path map), this
	* action can also create manifest consisting of just exec paths for historical reasons.
	*
	* <p>This action carefully avoids building the manifest content in memory because it can be large.
	*/
	@Immutable // if all ManifestWriter implementations are immutable
	public final class SourceManifestAction extends AbstractFileWriteAction
	implements AbstractFileWriteAction.FileContentsProvider {

	private static final String GUID = "07459553-a3d0-4d37-9d78-18ed942470f4";

	private static final Comparator<Map.Entry<PathFragment, Artifact>> ENTRY_COMPARATOR =
	(path1, path2) -> path1.getKey().getPathString().compareTo(path2.getKey().getPathString());
	private final Artifact repoMappingManifest;
	/**
	* Interface for defining manifest formatting and reporting specifics. Implementations must be
	* immutable.
	*/
	@VisibleForTesting
	interface ManifestWriter {

	/**
	* Writes a single line of manifest output.
	*
	* @param manifestWriter the output stream
	* @param rootRelativePath path of an entry relative to the manifest's root
	* @param symlink (optional) symlink that resolves the above path
	*/
	void writeEntry(
	Writer manifestWriter, PathFragment rootRelativePath, @Nullable Artifact symlink)
	throws IOException;

	/** Fulfills {@link com.google.devtools.build.lib.actions.AbstractAction#getMnemonic()} */
	String getMnemonic();

	/**
	* Fulfills {@link com.google.devtools.build.lib.actions.AbstractAction#getRawProgressMessage()}
	*/
	String getRawProgressMessage();

	/**
	* Fulfills {@link AbstractFileWriteAction#isRemotable()}.
	*
	* @return
	*/
	boolean isRemotable();

	/** Whether the manifest includes absolute paths to artifacts. */
	boolean emitsAbsolutePaths();
	}

	/** The strategy we use to write manifest entries. */
	private final ManifestWriter manifestWriter;

	/** The runfiles for which to create the symlink tree. */
	private final Runfiles runfiles;

	private final boolean remotableSourceManifestActions;

	private NestedSet<Artifact> symlinkArtifacts = null;

	/**
	* Creates a new AbstractSourceManifestAction instance using latin1 encoding to write the manifest
	* file and with a specified root path for manifest entries.
	*
	* @param manifestWriter the strategy to use to write manifest entries
	* @param owner the action owner
	* @param primaryOutput the file to which to write the manifest
	* @param runfiles runfiles
	*/
	@VisibleForTesting
	SourceManifestAction(
	ManifestWriter manifestWriter, ActionOwner owner, Artifact primaryOutput, Runfiles runfiles) {
	this(manifestWriter, owner, primaryOutput, runfiles, null, false);
	}

	/**
	* Creates a new AbstractSourceManifestAction instance using latin1 encoding to write the manifest
	* file and with a specified root path for manifest entries.
	*
	* @param manifestWriter the strategy to use to write manifest entries
	* @param owner the action owner
	* @param primaryOutput the file to which to write the manifest
	* @param runfiles runfiles
	* @param repoMappingManifest the repository mapping manifest for runfiles
	*/
	public SourceManifestAction(
	ManifestWriter manifestWriter,
	ActionOwner owner,
	Artifact primaryOutput,
	Runfiles runfiles,
	@Nullable Artifact repoMappingManifest,
	boolean remotableSourceManifestActions) {
	// The real set of inputs is computed in #getInputs().
	super(owner, NestedSetBuilder.emptySet(Order.STABLE_ORDER), primaryOutput, false);
	this.manifestWriter = manifestWriter;
	this.runfiles = runfiles;
	this.repoMappingManifest = repoMappingManifest;
	this.remotableSourceManifestActions = remotableSourceManifestActions;
	}

	/**
	* The manifest entry for a symlink artifact should contain the target of the symlink rather than
	* its exec path. Reading the symlink target requires that the symlink artifact is declared as an
	* input of this action. Since declaring all runfiles as inputs of the manifest action would
	* unnecessarily delay its execution, this action exceptionally overrides {@link
	* AbstractAction#getInputs()} and filters out the non-symlink runfiles by flattening the nested
	* set of runfiles. Benchmarks confirmed that this does not regress performance.
	*
	* <p>Alternatives considered:
	*
	* <ul>
	* <li>Having users separate normal artifacts from symlink artifacts during analysis: Makes it
	* impossible to pass symlink artifacts to rules that aren't aware of them and requires the
	* use of custom providers to pass symlinks to stage as inputs to actions.
	* <li>Reaching into {@link ActionExecutionContext} to look up the generating action of symlink
	* artifacts and retrieving the target from {@link UnresolvedSymlinkAction}: This would not
	* work for symlinks whose target is determined in the execution phase.
	* <li>Input discovery: Complex and error-prone in general and conceptually not necessary here -
	* we already know what the inputs will be during analysis, we just want to delay the
	* required computations.
	* </ul>
	*/
	@Override
	public synchronized NestedSet<Artifact> getInputs() {
	if (symlinkArtifacts == null) {
	ImmutableList<Artifact> symlinks =
	runfiles.getArtifacts().toList().stream()
	.filter(Artifact::isSymlink)
	.collect(toImmutableList());
	symlinkArtifacts = NestedSetBuilder.wrap(Order.STABLE_ORDER, symlinks);
	}
	return symlinkArtifacts;
	}

	@VisibleForTesting
	public void writeOutputFile(OutputStream out, @Nullable EventHandler eventHandler)
	throws IOException {
	writeFile(
	out,
	runfiles.getRunfilesInputs(eventHandler, getOwner().getLocation(), repoMappingManifest));
	}

	/**
	* Get the contents of a file internally using an in memory output stream.
	*
	* @return returns the file contents as a string.
	*/
	@Override
	public String getFileContents(@Nullable EventHandler eventHandler) throws IOException {
	ByteArrayOutputStream stream = new ByteArrayOutputStream();
	writeOutputFile(stream, eventHandler);
	return stream.toString(UTF_8);
	}

	@Override
	public String getStarlarkContent() throws IOException {
	return getFileContents(null);
	}

	@Override
	public DeterministicWriter newDeterministicWriter(ActionExecutionContext ctx) {
	final Map<PathFragment, Artifact> runfilesInputs =
	runfiles.getRunfilesInputs(
	ctx.getEventHandler(), getOwner().getLocation(), repoMappingManifest);
	return out -> writeFile(out, runfilesInputs);
	}

	@Override
	public boolean isRemotable() {
	return remotableSourceManifestActions \|\| manifestWriter.isRemotable();
	}

	/**
	* Sort the entries in both the normal and root manifests and write the output file.
	*
	* @param out is the message stream to write errors to.
	* @param output The actual mapping of the output manifest.
	* @throws IOException
	*/
	private void writeFile(OutputStream out, Map<PathFragment, Artifact> output) throws IOException {
	Writer manifestFile = new BufferedWriter(new OutputStreamWriter(out, ISO_8859_1));
	List<Map.Entry<PathFragment, Artifact>> sortedManifest = new ArrayList<>(output.entrySet());
	sortedManifest.sort(ENTRY_COMPARATOR);
	for (Map.Entry<PathFragment, Artifact> line : sortedManifest) {
	manifestWriter.writeEntry(manifestFile, line.getKey(), line.getValue());
	}

	manifestFile.flush();
	}

	@Override
	public String getMnemonic() {
	return manifestWriter.getMnemonic();
	}

	@Override
	protected String getRawProgressMessage() {
	return manifestWriter.getRawProgressMessage() + " for " + getOwner().getLabel();
	}

	@Override
	protected void computeKey(
	ActionKeyContext actionKeyContext,
	@Nullable Artifact.ArtifactExpander artifactExpander,
	Fingerprint fp) {
	fp.addString(GUID);
	fp.addBoolean(remotableSourceManifestActions);
	runfiles.fingerprint(actionKeyContext, fp, manifestWriter.emitsAbsolutePaths());
	fp.addBoolean(repoMappingManifest != null);
	if (repoMappingManifest != null) {
	fp.addPath(repoMappingManifest.getExecPath());
	}
	}

	@Override
	public String describeKey() {
	return String.format(
	"GUID: %s\nremotableSourceManifestActions: %s\nrunfiles: %s\n",
	GUID,
	remotableSourceManifestActions,
	runfiles.describeFingerprint(manifestWriter.emitsAbsolutePaths()));
	}

	/** Supported manifest writing strategies. */
	public enum ManifestType implements ManifestWriter {

	/**
	* Writes each line as:
	*
	* <p>[rootRelativePath] [resolvingSymlink]
	*
	* <p>This strategy is suitable for creating an input manifest to a source view tree. Its output
	* is a valid input to {@link com.google.devtools.build.lib.analysis.actions.SymlinkTreeAction}.
	*/
	SOURCE_SYMLINKS {
	@Override
	public void writeEntry(Writer manifestWriter, PathFragment rootRelativePath, Artifact symlink)
	throws IOException {
	manifestWriter.append(rootRelativePath.getPathString());
	// This trailing whitespace is REQUIRED to process the single entry line correctly.
	manifestWriter.append(' ');
	if (symlink != null) {
	if (symlink.isSymlink()) {
	manifestWriter.append(symlink.getPath().readSymbolicLink().getPathString());
	} else {
	manifestWriter.append(symlink.getPath().getPathString());
	}
	}
	manifestWriter.append('\n');
	}

	@Override
	public String getMnemonic() {
	return "SourceSymlinkManifest";
	}

	@Override
	public String getRawProgressMessage() {
	return "Creating source manifest";
	}

	@Override
	public boolean isRemotable() {
	// There is little gain to remoting these, since they include absolute path names inline.
	return false;
	}

	@Override
	public boolean emitsAbsolutePaths() {
	return true;
	}
	},

	/**
	* Writes each line as:
	*
	* <p>[rootRelativePath]
	*
	* <p>This strategy is suitable for an input into a packaging system (notably .par) that
	* consumes a list of all source files but needs that list to be constant with respect to how
	* the user has their client laid out on local disk.
	*/
	SOURCES_ONLY {
	@Override
	public void writeEntry(Writer manifestWriter, PathFragment rootRelativePath, Artifact symlink)
	throws IOException {
	manifestWriter.append(rootRelativePath.getPathString());
	manifestWriter.append('\n');
	manifestWriter.flush();
	}

	@Override
	public String getMnemonic() {
	return "PackagingSourcesManifest";
	}

	@Override
	public String getRawProgressMessage() {
	return "Creating file sources list";
	}

	@Override
	public boolean isRemotable() {
	// Source-only symlink manifest has root-relative paths and does not include absolute paths.
	return true;
	}

	@Override
	public boolean emitsAbsolutePaths() {
	return false;
	}
	}
	}
	}