RELNOTES[NEW]: Added --relative_locations flag to the query command t…

…o make the locations of build files relative to the workspace root with protobuf and XML outputs

Protobuf and XML outputs of query are non-deterministic. This flag is a first step to make genquery deterministic accross machine.

--
MOS_MIGRATED_REVID=88428100

src/main/java/com/google/devtools/build/lib/events/Location.java

@@ -147,9 +147,13 @@ public LineAndColumn getEndLineAndColumn() {
    * </pre>
    */
   public String print() {
+    return printWithPath(getPath());
+  }
+
+  private String printWithPath(PathFragment path) {
     StringBuilder buf = new StringBuilder();
-    if (getPath() != null) {
-      buf.append(getPath()).append(':');
+    if (path != null) {
+      buf.append(path).append(':');
     }
     LineAndColumn start = getStartLineAndColumn();
     if (start == null) {
@@ -165,6 +169,37 @@ public String print() {
     return buf.toString();
   }
 
+  /**
+   * A default implementation of toString() that formats the location in the following ways based on
+   * the amount of information available:
+   *
+   * <pre>
+   *   "foo.cc:23:2"
+   *   "23:2"
+   *   "foo.cc:char offsets 123--456"
+   *   "char offsets 123--456"
+   *</pre>
+   *
+   * <p>This version replace the package's path with the relative package path. I.e., if {@code
+   * packagePath} is equivalent to "/absolute/path/to/workspace/pack/age" and {@code
+   * relativePackage} is equivalent to "pack/age" then the result for the 2nd character of the 23rd
+   * line of the "foo/bar.cc" file in "pack/age" would be "pack/age/foo/bar.cc:23:2" whereas with
+   * {@link #print()} the result would be "/absolute/path/to/workspace/pack/age/foo/bar.cc:23:2".
+   * 
+   * <p>If {@code packagePath} is not a parent of the location path, then the result of this
+   * function is the same as the result of {@link #print()}.
+   */
+  public String print(PathFragment packagePath, PathFragment relativePackage) {
+    PathFragment path = getPath();
+    if (path == null) {
+      return printWithPath(null);
+    } else if (path.startsWith(packagePath)) {
+      return printWithPath(relativePackage.getRelative(path.relativeTo(packagePath)));
+    } else {
+      return printWithPath(path);
+    }
+  }
+
   /**
    * Prints the object in a sort of reasonable way. This should never be used in user-visible
    * places, only for debugging and testing.

src/main/java/com/google/devtools/build/lib/query2/output/OutputFormatter.java

@@ -484,4 +484,20 @@ protected static Pair<Iterable<Object>, AttributeValueSource> getAttributeValues
 
     return Pair.of((Iterable<Object>) values, source);
   }
+
+  /**
+   * Returns the target location, eventually stripping out the workspace path to obtain a relative
+   * target (stable across machines / workspaces).
+   *
+   * @param target The target to extract location from.
+   * @param relative Whether to return a relative path or not.
+   * @return the target location
+   */
+  protected static String getLocation(Target target, boolean relative) {
+    Location location = target.getLocation();
+    return relative 
+        ? location.print(target.getPackage().getPackageDirectory().asFragment(),
+            target.getPackage().getNameFragment())
+        : location.print();
+  }
 }

src/main/java/com/google/devtools/build/lib/query2/output/ProtoOutputFormatter.java

@@ -79,6 +79,7 @@ public class ProtoOutputFormatter extends OutputFormatter implements UnorderedFo
   public static final String RULE_IMPLEMENTATION_HASH_ATTR_NAME = "$rule_implementation_hash";
 
   private BinaryPredicate<Rule, Attribute> dependencyFilter;
+  private boolean relativeLocations = false;
 
   protected void setDependencyFilter(QueryOptions options) {
     this.dependencyFilter = OutputFormatter.getDependencyFilter(options);
@@ -92,6 +93,8 @@ public String getName() {
   @Override
   public void outputUnordered(QueryOptions options, Iterable<Target> result, PrintStream out)
       throws IOException {
+    relativeLocations = options.relativeLocations;
+
     setDependencyFilter(options);
 
     Build.QueryResult.Builder queryResult = Build.QueryResult.newBuilder();
@@ -124,7 +127,7 @@ private void addTarget(Build.QueryResult.Builder queryResult, Target target) {
   protected Build.Target toTargetProtoBuffer(Target target) {
     Build.Target.Builder targetPb = Build.Target.newBuilder();
 
-    String location = target.getLocation().print();
+    String location = getLocation(target, relativeLocations);
     if (target instanceof Rule) {
       Rule rule = (Rule) target;
       Build.Rule.Builder rulePb = Build.Rule.newBuilder()

src/main/java/com/google/devtools/build/lib/query2/output/QueryOptions.java

@@ -128,6 +128,15 @@ public class QueryOptions extends OptionsBase {
           + "targets.")
   public List<String> universeScope;
 
+  @Option(name = "relative_locations",
+      defaultValue = "false",
+      category = "query",
+      help = "If true, the location of BUILD files in xml and proto outputs will be relative. "
+        + "By default, the location output is an absolute path and will not be consistent "
+        + "across machines. You can set this option to true to have a consistent result "
+        + "across machines.")
+  public boolean relativeLocations;
+
   /**
    * Return the current options as a set of QueryEnvironment settings.
    */

src/main/java/com/google/devtools/build/lib/query2/output/XmlOutputFormatter.java

@@ -56,6 +56,7 @@ class XmlOutputFormatter extends OutputFormatter implements OutputFormatter.Unor
 
   private boolean xmlLineNumbers;
   private boolean showDefaultValues;
+  private boolean relativeLocations;
   private BinaryPredicate<Rule, Attribute> dependencyFilter;
 
   @Override
@@ -67,6 +68,7 @@ public String getName() {
   public void outputUnordered(QueryOptions options, Iterable<Target> result, PrintStream out) {
     this.xmlLineNumbers = options.xmlLineNumbers;
     this.showDefaultValues = options.xmlShowDefaultValues;
+    this.relativeLocations = options.relativeLocations;
     this.dependencyFilter = OutputFormatter.getDependencyFilter(options);
 
     Document doc;
@@ -182,7 +184,7 @@ private Element createTargetElement(Document doc, Target target) {
     }
 
     elem.setAttribute("name", target.getLabel().toString());
-    String location = target.getLocation().print();
+    String location = getLocation(target, relativeLocations);
     if (!xmlLineNumbers) {
       int firstColon = location.indexOf(':');
       if (firstColon != -1) {

src/test/java/com/google/devtools/build/lib/events/EventTestTemplate.java

@@ -32,7 +32,7 @@ public abstract class EventTestTemplate {
   @Before
   public void setUp() throws Exception {
     String message = "This is not an error message.";
-    path = scratch.path("/my/sample/path.txt");
+    path = scratch.path("/path/to/workspace/my/sample/path.txt");
 
     location = Location.fromPathAndStartColumn(path, 21, 31, new LineAndColumn(3, 4));
 

src/test/java/com/google/devtools/build/lib/events/LocationTest.java

@@ -16,6 +16,8 @@
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNull;
 
+import com.google.devtools.build.lib.vfs.PathFragment;
+
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;
@@ -33,4 +35,17 @@ public void fromFile() throws Exception {
     assertNull(location.getEndLineAndColumn());
     assertEquals(path + ":1", location.print());
   }
+
+  @Test
+  public void testPrintRelative() throws Exception {
+    Location location = Location.fromFile(path);
+    assertEquals("/path/to/workspace/my/sample/path.txt:1",
+        location.print(new PathFragment("/some/other/path"), new PathFragment("baz")));
+    assertEquals("new/sample/path.txt:1",
+        location.print(new PathFragment("/path/to/workspace/my"), new PathFragment("new")));
+    assertEquals("new/path.txt:1",
+        location.print(new PathFragment("/path/to/workspace/my/sample"), new PathFragment("new")));
+    assertEquals("new:1", location.print(new PathFragment("/path/to/workspace/my/sample/path.txt"),
+        new PathFragment("new")));
+  }
 }

src/test/java/com/google/devtools/build/lib/events/PrintingEventHandlerTest.java

@@ -34,7 +34,7 @@ public void collectsEvents() {
     PrintingEventHandler handler = new PrintingEventHandler(EventKind.ERRORS_AND_WARNINGS);
     handler.setOutErr(recordingOutErr);
     handler.handle(event);
-    MoreAsserts.assertEqualsUnifyingLineEnds("WARNING: /my/sample/path.txt:3:4: "
+    MoreAsserts.assertEqualsUnifyingLineEnds("WARNING: /path/to/workspace/my/sample/path.txt:3:4: "
                  + "This is not an error message.\n",
                  recordingOutErr.errAsLatin1());
     assertThat(recordingOutErr.outAsLatin1()).isEmpty();