diff --git a/base/src/com/google/idea/blaze/base/qsync/cache/ArtifactTrackerImpl.java b/base/src/com/google/idea/blaze/base/qsync/cache/ArtifactTrackerImpl.java
index 4e8fa3b3d6c..d0c35439f84 100644
--- a/base/src/com/google/idea/blaze/base/qsync/cache/ArtifactTrackerImpl.java
+++ b/base/src/com/google/idea/blaze/base/qsync/cache/ArtifactTrackerImpl.java
@@ -72,7 +72,9 @@
 import com.google.idea.blaze.common.PrintOutput;
 import com.google.idea.blaze.exception.BuildException;
 import com.google.idea.blaze.qsync.GeneratedSourceProjectUpdater;
+import com.google.idea.blaze.qsync.GeneratedSourceProjectUpdater.GeneratedSourceJar;
 import com.google.idea.blaze.qsync.SrcJarProjectUpdater;
+import com.google.idea.blaze.qsync.TestSourceGlobMatcher;
 import com.google.idea.blaze.qsync.cc.CcDependenciesInfo;
 import com.google.idea.blaze.qsync.project.BuildGraphData;
 import com.google.idea.blaze.qsync.project.ProjectDefinition;
@@ -81,7 +83,7 @@
 import com.google.idea.common.experiments.BoolExperiment;
 import com.google.protobuf.ExtensionRegistry;
 import com.intellij.openapi.diagnostic.Logger;
-import com.intellij.openapi.util.io.FileUtil;
+import com.intellij.openapi.util.io.FileUtilRt;
 import com.intellij.openapi.util.text.StringUtil;
 import java.io.File;
 import java.io.IOException;
@@ -609,18 +611,18 @@ private void updateMaps(Set<Label> targets, JavaArtifacts newArtifacts) {
       ImmutableSet.of("jar", "zip", "srcjar");
 
   private static boolean hasJarOrZipExtension(Path p) {
-    return JAR_ZIP_EXTENSIONS.contains(FileUtil.getExtension(p.toString()));
+    return JAR_ZIP_EXTENSIONS.contains(FileUtilRt.getExtension(p.toString()));
   }
 
   @Override
   public ProjectProto.Project updateProjectProto(
       ProjectProto.Project projectProto, BuildGraphData graph, Context<?> context)
       throws BuildException {
-    return updateProjectProtoForJavaDeps(projectProto);
+    return updateProjectProtoForJavaDeps(projectProto, graph);
   }
 
-  private ProjectProto.Project updateProjectProtoForJavaDeps(ProjectProto.Project projectProto)
-      throws BuildException {
+  private ProjectProto.Project updateProjectProtoForJavaDeps(
+      ProjectProto.Project projectProto, BuildGraphData graph) throws BuildException {
 
     Set<ProjectPath> generatedJavaSrcRoots = Sets.newHashSet();
 
@@ -641,26 +643,37 @@ private ProjectProto.Project updateProjectProtoForJavaDeps(ProjectProto.Project
       }
     }
 
-    ImmutableSet<ProjectPath> generatedProjectSrcJars;
-    Path srcJarDir =
-        generatedSrcFileCacheDirectory.resolve(JavaSourcesArchiveCacheLayout.ROOT_DIRECTORY_NAME);
-    try (Stream<Path> pathStream =
-        srcJarDir.toFile().exists() ? Files.walk(srcJarDir) : Stream.empty()) {
-      generatedProjectSrcJars =
-          pathStream
-              .filter(Files::isRegularFile)
-              .map(ideProjectBasePath::relativize)
-              .map(ProjectPath::projectRelative)
-              .collect(toImmutableSet());
-    } catch (IOException e) {
-      throw new BuildException(e);
+    TestSourceGlobMatcher testSourceMatcher = TestSourceGlobMatcher.create(projectDefinition);
+    ImmutableSet.Builder<GeneratedSourceJar> generatedProjectSrcJars = ImmutableSet.builder();
+    for (ArtifactInfo ai : javaArtifacts.values()) {
+      if (!projectDefinition.isIncluded(ai.label())) {
+        continue;
+      }
+      for (Path blazeOutRelativePath : ai.genSrcs()) {
+        // TODO(mathewi) depending on `JAVA_ARCHIVE_EXTENSIONS` here exposes a design problem, we
+        //  shouldn't have to depend on such implementation details. Figure out a better design
+        //  for the dance between this class and the cache.
+        if (!JavaSourcesArchiveCacheLayout.JAVA_ARCHIVE_EXTENSIONS.contains(
+            FileUtilRt.getExtension(blazeOutRelativePath.toString()))) {
+          continue;
+        }
+        Optional<Path> artifactPath = generatedSrcFileCache.getCacheFile(blazeOutRelativePath);
+        if (artifactPath.isEmpty()) {
+          logger.warn("No cached artifact found for source jar " + blazeOutRelativePath);
+          continue;
+        }
+        generatedProjectSrcJars.add(
+            GeneratedSourceJar.create(
+                ProjectPath.projectRelative(artifactPath.get()),
+                testSourceMatcher.matches(ai.label().getPackage())));
+      }
     }
 
     GeneratedSourceProjectUpdater updater =
         new GeneratedSourceProjectUpdater(
             projectProto,
             ImmutableSet.copyOf(generatedJavaSrcRoots),
-            generatedProjectSrcJars,
+            generatedProjectSrcJars.build(),
             projectPathResolver);
 
     projectProto = updater.addGenSrcContentEntry();
diff --git a/base/src/com/google/idea/blaze/base/qsync/cache/JavaSourcesArchiveCacheLayout.java b/base/src/com/google/idea/blaze/base/qsync/cache/JavaSourcesArchiveCacheLayout.java
index a038517cfcc..75d6d166a06 100644
--- a/base/src/com/google/idea/blaze/base/qsync/cache/JavaSourcesArchiveCacheLayout.java
+++ b/base/src/com/google/idea/blaze/base/qsync/cache/JavaSourcesArchiveCacheLayout.java
@@ -29,7 +29,7 @@
 /** Places java source archives in a dedicated subdirectory. */
 public class JavaSourcesArchiveCacheLayout implements CacheLayout {
 
-  private static final ImmutableSet<String> JAVA_ARCHIVE_EXTENSIONS =
+  public static final ImmutableSet<String> JAVA_ARCHIVE_EXTENSIONS =
       ImmutableSet.of("jar", "srcjar");
 
   /** Cache subdirectory in which all source jars are placed. */
diff --git a/querysync/java/com/google/idea/blaze/qsync/GeneratedSourceProjectUpdater.java b/querysync/java/com/google/idea/blaze/qsync/GeneratedSourceProjectUpdater.java
index 9ce84b33ca1..ce4f9346d9f 100644
--- a/querysync/java/com/google/idea/blaze/qsync/GeneratedSourceProjectUpdater.java
+++ b/querysync/java/com/google/idea/blaze/qsync/GeneratedSourceProjectUpdater.java
@@ -17,6 +17,7 @@
 
 import static com.google.idea.blaze.qsync.SrcJarInnerPathFinder.AllowPackagePrefixes.ALLOW_NON_EMPTY_PACKAGE_PREFIXES;
 
+import com.google.auto.value.AutoValue;
 import com.google.common.collect.ImmutableSet;
 import com.google.idea.blaze.qsync.SrcJarInnerPathFinder.JarPath;
 import com.google.idea.blaze.qsync.project.ProjectPath;
@@ -26,9 +27,24 @@
 /** Updates project protos with a content entry for generated sources */
 public class GeneratedSourceProjectUpdater {
 
+  /**
+   * Information about a generated source jar, comprising its path and whether or not it's test only
+   * source.
+   */
+  @AutoValue
+  public abstract static class GeneratedSourceJar {
+    public abstract ProjectPath path();
+
+    public abstract boolean isTestSource();
+
+    public static GeneratedSourceJar create(ProjectPath path, boolean isTestSource) {
+      return new AutoValue_GeneratedSourceProjectUpdater_GeneratedSourceJar(path, isTestSource);
+    }
+  }
+
   private final Project project;
   private final ImmutableSet<ProjectPath> genSrcRoots;
-  private final ImmutableSet<ProjectPath> genSrcJars;
+  private final ImmutableSet<GeneratedSourceJar> genSrcJars;
   private final ProjectPath.Resolver resolver;
 
   private final SrcJarInnerPathFinder srcJarInnerPathFinder;
@@ -36,7 +52,7 @@ public class GeneratedSourceProjectUpdater {
   public GeneratedSourceProjectUpdater(
       Project project,
       ImmutableSet<ProjectPath> genSrcFileFolders,
-      ImmutableSet<ProjectPath> genSrcJars,
+      ImmutableSet<GeneratedSourceJar> genSrcJars,
       ProjectPath.Resolver resolver) {
     this.project = project;
     this.genSrcRoots = genSrcFileFolders;
@@ -70,15 +86,16 @@ public Project addGenSrcContentEntry() {
       workspaceModule.addContentEntries(genSourcesContentEntry);
     }
 
-    for (ProjectPath path : genSrcJars) {
+    for (GeneratedSourceJar jar : genSrcJars) {
       ProjectProto.ContentEntry.Builder genSrcJarContentEntry =
-          ProjectProto.ContentEntry.newBuilder().setRoot(path.toProto());
+          ProjectProto.ContentEntry.newBuilder().setRoot(jar.path().toProto());
       for (JarPath innerPath :
-          srcJarInnerPathFinder.findInnerJarPaths(resolver.resolve(path).toFile())) {
+          srcJarInnerPathFinder.findInnerJarPaths(resolver.resolve(jar.path()).toFile())) {
         genSrcJarContentEntry.addSources(
             ProjectProto.SourceFolder.newBuilder()
-                .setProjectPath(path.withInnerJarPath(innerPath.path).toProto())
+                .setProjectPath(jar.path().withInnerJarPath(innerPath.path).toProto())
                 .setIsGenerated(true)
+                .setIsTest(jar.isTestSource())
                 .setPackagePrefix(innerPath.packagePrefix));
       }
       workspaceModule.addContentEntries(genSrcJarContentEntry);
diff --git a/querysync/java/com/google/idea/blaze/qsync/GraphToProjectConverter.java b/querysync/java/com/google/idea/blaze/qsync/GraphToProjectConverter.java
index 2814692cda9..28de8d90af7 100644
--- a/querysync/java/com/google/idea/blaze/qsync/GraphToProjectConverter.java
+++ b/querysync/java/com/google/idea/blaze/qsync/GraphToProjectConverter.java
@@ -402,8 +402,7 @@ public ProjectProto.Project createProject(BuildGraphData graph) throws BuildExce
 
     ListMultimap<Path, Path> excludesByRootDirectory =
         projectDefinition.getExcludesByRootDirectory();
-    TestSourceGlobMatcher testSourceGlobMatcher =
-        new TestSourceGlobMatcher(projectDefinition.testSources());
+    TestSourceGlobMatcher testSourceGlobMatcher = TestSourceGlobMatcher.create(projectDefinition);
     for (Path dir : projectDefinition.projectIncludes()) {
       ProjectProto.ContentEntry.Builder contentEntry =
           ProjectProto.ContentEntry.newBuilder()
diff --git a/querysync/java/com/google/idea/blaze/qsync/TestSourceGlobMatcher.java b/querysync/java/com/google/idea/blaze/qsync/TestSourceGlobMatcher.java
index 7140945df6a..84c3f2fba6a 100644
--- a/querysync/java/com/google/idea/blaze/qsync/TestSourceGlobMatcher.java
+++ b/querysync/java/com/google/idea/blaze/qsync/TestSourceGlobMatcher.java
@@ -17,7 +17,9 @@
 
 import static com.google.common.collect.ImmutableSet.toImmutableSet;
 
+import com.google.common.annotations.VisibleForTesting;
 import com.google.common.collect.ImmutableSet;
+import com.google.idea.blaze.qsync.project.ProjectDefinition;
 import java.io.File;
 import java.nio.file.Path;
 
@@ -29,6 +31,11 @@ public class TestSourceGlobMatcher {
 
   private final ImmutableSet<String> testSourceGlobs;
 
+  public static TestSourceGlobMatcher create(ProjectDefinition projectDefinition) {
+    return new TestSourceGlobMatcher(projectDefinition.testSources());
+  }
+
+  @VisibleForTesting
   public TestSourceGlobMatcher(ImmutableSet<String> testSources) {
     this.testSourceGlobs =
         testSources.stream().map(TestSourceGlobMatcher::modifyPattern).collect(toImmutableSet());
diff --git a/querysync/javatests/com/google/idea/blaze/qsync/GeneratedSourceProjectUpdaterTest.java b/querysync/javatests/com/google/idea/blaze/qsync/GeneratedSourceProjectUpdaterTest.java
index 9a31c552410..d7815508c97 100644
--- a/querysync/javatests/com/google/idea/blaze/qsync/GeneratedSourceProjectUpdaterTest.java
+++ b/querysync/javatests/com/google/idea/blaze/qsync/GeneratedSourceProjectUpdaterTest.java
@@ -20,6 +20,7 @@
 import static com.google.idea.blaze.qsync.QuerySyncTestUtils.createSrcJar;
 
 import com.google.common.collect.ImmutableSet;
+import com.google.idea.blaze.qsync.GeneratedSourceProjectUpdater.GeneratedSourceJar;
 import com.google.idea.blaze.qsync.QuerySyncTestUtils.PathPackage;
 import com.google.idea.blaze.qsync.project.ProjectPath;
 import com.google.idea.blaze.qsync.project.ProjectPath.Resolver;
@@ -105,7 +106,7 @@ public void addGenSrcContentEntry_withGenSrcJar_addsContentEntry() throws Except
         new GeneratedSourceProjectUpdater(
             project,
             ImmutableSet.of(),
-            ImmutableSet.of(srcJarPath),
+            ImmutableSet.of(GeneratedSourceJar.create(srcJarPath, false)),
             Resolver.create(workspaceRoot, projectRoot));
 
     ProjectProto.Project newProject = updater.addGenSrcContentEntry();
@@ -120,6 +121,29 @@ public void addGenSrcContentEntry_withGenSrcJar_addsContentEntry() throws Except
     ProjectProto.SourceFolder sourceFolder = contentEntry.getSources(0);
     assertThat(sourceFolder.getProjectPath()).isEqualTo(srcJarPath.toProto());
     assertThat(sourceFolder.getIsGenerated()).isTrue();
+    assertThat(sourceFolder.getIsTest()).isFalse();
+  }
+
+  @Test
+  public void addGenSrcContentEntry_withGenSrcJar_addsContentEntry_testSources() throws Exception {
+    ProjectProto.Project project =
+        ProjectProtos.forTestProject(TestData.JAVA_LIBRARY_NO_DEPS_QUERY);
+
+    ProjectPath srcJarPath = ProjectPath.projectRelative("generated/srcjars/sources.srcjar");
+    createSrcJar(
+        projectRoot.resolve(srcJarPath.relativePath()),
+        PathPackage.of("com/package/Class.java", "com.package"));
+
+    GeneratedSourceProjectUpdater updater =
+        new GeneratedSourceProjectUpdater(
+            project,
+            ImmutableSet.of(),
+            ImmutableSet.of(GeneratedSourceJar.create(srcJarPath, true)),
+            Resolver.create(workspaceRoot, projectRoot));
+
+    ProjectProto.Project newProject = updater.addGenSrcContentEntry();
+
+    assertThat(newProject.getModules(0).getContentEntries(1).getSources(0).getIsTest()).isTrue();
   }
 
   @Test
@@ -137,7 +161,7 @@ public void addGenSrcContentEntry_withGenSrcJarWithNestedRoot_addsContentEntryWi
         new GeneratedSourceProjectUpdater(
             project,
             ImmutableSet.of(),
-            ImmutableSet.of(srcJarPath),
+            ImmutableSet.of(GeneratedSourceJar.create(srcJarPath, false)),
             Resolver.create(workspaceRoot, projectRoot));
 
     ProjectProto.Project newProject = updater.addGenSrcContentEntry();