Move summarization action to Aspects.

tree_shaker/src/main/java/com/google/devtools/treeshaker/Options.java

@@ -17,6 +17,7 @@
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Preconditions;
 import com.google.common.base.Strings;
+import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Lists;
 import com.google.common.io.Files;
 import com.google.common.io.Resources;
@@ -67,6 +68,7 @@ class Options {
   private File outputFile = new File("tree-shaker-report.txt");
   private LibraryInfo summary;
   private String summaryOutputFile;
+  private List<LibraryInfo> summaries = Lists.newArrayList();
 
   // The default source version number if not passed with -source is determined from the system
   // properties of the running java version after parsing the argument list.
@@ -135,11 +137,27 @@ public LibraryInfo getSummary() {
   public void setSummary(LibraryInfo summary) {
     this.summary = summary;
   }
-
+
+  public List<LibraryInfo> getSummaries() {
+    return summaries;
+  }
+
+  public void setSummaries(List<LibraryInfo> summaries) {
+    this.summaries = summaries;
+  }
+
+  public void addSummary(LibraryInfo summary) {
+    this.summaries.add(summary);
+  }
+
   public String getSummaryOutputFile() {
     return summaryOutputFile;
   }
 
+  public void setSummaryOutputFile(String summaryOutputFile) {
+    this.summaryOutputFile = summaryOutputFile;
+  }
+
   private void addManifest(String manifestFile) throws IOException {
     BufferedReader in = new BufferedReader(new FileReader(new File(manifestFile)));
     try {
@@ -192,6 +210,16 @@ public static Options parse(String[] args) throws IOException {
     return options;
   }
 
+  private static List<LibraryInfo> readSummaries(List<String> summaries) throws IOException {
+    List<LibraryInfo> result = Lists.newArrayList();
+    for (String summary : summaries) {
+      result.add(
+          LibraryInfo.parseFrom(
+              Files.toByteArray(new File(summary)), ExtensionRegistry.getGeneratedRegistry()));
+    }
+    return result;
+  }
+
   private static void processArgsFile(String filename, Options options) throws IOException {
     if (filename.isEmpty()) {
       usage("no @ file specified");
@@ -220,6 +248,11 @@ private static void processArgs(String[] args, Options options) throws IOExcepti
           usage("-classpath requires an argument");
         }
         options.classpath = args[nArg];
+      } else if (arg.equals("-summaries")) {
+        if (++nArg == args.length) {
+          usage("--summaries requires an argument");
+        }
+        options.setSummaries(readSummaries(ImmutableList.copyOf(args[nArg].split(":"))));
       } else if (arg.equals("-summary")) {
         if (++nArg == args.length) {
           usage("-summary requires an argument");

tree_shaker/src/main/java/com/google/devtools/treeshaker/TreeShaker.java

@@ -14,8 +14,11 @@
 
 package com.google.devtools.treeshaker;
 
+import static com.google.common.collect.ImmutableList.toImmutableList;
+
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Strings;
+import com.google.common.collect.ImmutableList;
 import com.google.common.flogger.GoogleLogger;
 import com.google.common.io.Files;
 import com.google.devtools.j2objc.ast.CompilationUnit;
@@ -170,6 +173,12 @@ private TypeGraphBuilder createTypeGraphBuilder() throws IOException {
       LibraryInfo info = options.getSummary();
       LibraryInfo markedInfo = UsedCodeMarker.mark(info, options.getTreeShakerRoots());
       return new TypeGraphBuilder(markedInfo);
+    } else if (!options.getSummaries().isEmpty()) {
+      ImmutableList<LibraryInfo> markedInfo =
+          options.getSummaries().stream()
+              .map(summary -> UsedCodeMarker.mark(summary, options.getTreeShakerRoots()))
+              .collect(toImmutableList());
+      return new TypeGraphBuilder(markedInfo);
     }
     return new TypeGraphBuilder(createLibraryInfo());
   }

tree_shaker/src/main/java/com/google/devtools/treeshaker/TypeGraphBuilder.java

@@ -16,6 +16,7 @@
 import java.util.Collection;
 import java.util.HashSet;
 import java.util.LinkedHashMap;
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
@@ -38,6 +39,25 @@ class TypeGraphBuilder {
     types = typesByName.values();
   }
 
+  TypeGraphBuilder(List<LibraryInfo> libraryInfos) {
+    Map<String, Type> typesByName = new LinkedHashMap<>();
+    externalTypeReferences = new HashSet<>();
+    unknownMethodReferences = new HashSet<>();
+    for (LibraryInfo libraryInfo : libraryInfos) {
+      for (TypeInfo typeInfo : libraryInfo.getTypeList()) {
+        Type type = Type.buildFrom(typeInfo, libraryInfo.getTypeMap(typeInfo.getTypeId()));
+        typesByName.put(type.getName(), type);
+      }
+    }
+
+    // Build cross-references between types and members
+    for (LibraryInfo libraryInfo : libraryInfos) {
+      buildCrossReferences(libraryInfo, typesByName);
+    }
+
+    types = typesByName.values();
+  }
+
   Collection<Type> getTypes() {
     return types;
   }