Add an ES6 module's relative path to closure as an implicit provide w…

…hen parsing deps.js files so that dependency graphs are correct.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=190859615

src/com/google/javascript/jscomp/deps/DepsFileParser.java

@@ -48,7 +48,6 @@
  */
 @GwtIncompatible("java.util.regex")
 public final class DepsFileParser extends JsFileLineParser {
-
   private static final Logger logger = Logger.getLogger(DepsFileParser.class.getName());
 
   /**
@@ -82,7 +81,7 @@ public final class DepsFileParser extends JsFileLineParser {
    * @param errorManager Handles parse errors.
    */
   public DepsFileParser(ErrorManager errorManager) {
-    this(Functions.<String>identity(), errorManager);
+    this(Functions.identity(), errorManager);
   }
 
   /**
@@ -166,17 +165,26 @@ protected boolean parseLine(String line) throws ParseException {
               + addDependencyParams, true);
         }
         // Parse the file path.
-        String path = pathTranslator.apply(parseJsString(depArgsMatch.group(1)));
+        String relativePath = parseJsString(depArgsMatch.group(1));
+        String path = pathTranslator.apply(relativePath);
+
+        List<String> provides = parseJsStringArray(depArgsMatch.group(2));
+        Map<String, String> loadFlags = parseLoadFlags(depArgsMatch.group(4));
+
+        // ES6 modules are require'd by path but do not provide them in the addDependency call.
+        if ("es6".equals(loadFlags.get("module"))) {
+          provides.add(relativePath);
+        }
 
         DependencyInfo depInfo =
             SimpleDependencyInfo.builder(path, filePath)
-                .setProvides(parseJsStringArray(depArgsMatch.group(2)))
+                .setProvides(provides)
                 .setRequires(
                     parseJsStringArray(depArgsMatch.group(3))
                         .stream()
                         .map(Require::parsedFromDeps)
                         .collect(toImmutableList()))
-                .setLoadFlags(parseLoadFlags(depArgsMatch.group(4)))
+                .setLoadFlags(loadFlags)
                 .build();
 
         if (logger.isLoggable(Level.FINE)) {

src/com/google/javascript/jscomp/deps/DepsGenerator.java

@@ -47,6 +47,7 @@
 import java.util.Set;
 import java.util.logging.Level;
 import java.util.logging.Logger;
+import java.util.stream.Collectors;
 
 /**
  * Generates deps.js files by scanning JavaScript files for
@@ -477,7 +478,18 @@ private Map<String, DependencyInfo> parseDepsFiles() throws IOException {
           reportNoDepsInDepsFile(file.getName());
         } else {
           for (DependencyInfo info : depInfos) {
-            depsFiles.put(info.getPathRelativeToClosureBase(), info);
+            // DepsFileParser adds an ES6 module's relative path to closure as a provide so that
+            // the resulting depgraph is valid. But we don't want to write this "fake" provide
+            // back out, so remove it here.
+            depsFiles.put(
+                info.getPathRelativeToClosureBase(),
+                SimpleDependencyInfo.Builder.from(info)
+                    .setProvides(
+                        info.getProvides()
+                            .stream()
+                            .filter(p -> !p.equals(info.getPathRelativeToClosureBase()))
+                            .collect(Collectors.toList()))
+                    .build());
           }
         }
       }

src/com/google/javascript/jscomp/deps/SimpleDependencyInfo.java

@@ -45,6 +45,16 @@ public static Builder builder(String srcPathRelativeToClosure, String pathOfDefi
    */
   @AutoValue.Builder
   public abstract static class Builder {
+    public static Builder from(DependencyInfo copy) {
+      return new AutoValue_SimpleDependencyInfo.Builder()
+          .setName(copy.getName())
+          .setPathRelativeToClosureBase(copy.getPathRelativeToClosureBase())
+          .setProvides(copy.getProvides())
+          .setRequires(copy.getRequires())
+          .setWeakRequires(copy.getWeakRequires())
+          .setLoadFlags(copy.getLoadFlags());
+    }
+
     abstract Builder setName(String name);
     abstract Builder setPathRelativeToClosureBase(String srcPathRelativeToClosure);
 

test/com/google/javascript/jscomp/deps/DepsFileParserTest.java

@@ -115,7 +115,7 @@ public void testBadLoadFlagsSyntax() {
     assertThat(errorManager.getWarningCount()).isEqualTo(0);
   }
 
-  public void testModule() {
+  public void testGoogModule() {
     List<DependencyInfo> result = parser.parseFile(SRC_PATH,
         "goog.addDependency('yes1', [], [], true);\n" +
         "goog.addDependency('yes2', [], [], false);\n");
@@ -126,6 +126,27 @@ public void testModule() {
     assertThat(result).isEqualTo(expected);
   }
 
+  public void testEs6Module() {
+    List<DependencyInfo> result =
+        parser.parseFile(
+            SRC_PATH,
+            "goog.addDependency('path/from/closure.js', [], ['nexttoclosure.js'], "
+                + "{'module':'es6'});\n"
+                + "goog.addDependency('nexttoclosure.js', [], [], {'module':'es6'});\n");
+    ImmutableList<DependencyInfo> expected =
+        ImmutableList.of(
+            SimpleDependencyInfo.builder("path/from/closure.js", SRC_PATH)
+                .setLoadFlags(ImmutableMap.of("module", "es6"))
+                .setProvides(ImmutableList.of("path/from/closure.js"))
+                .setRequires(Require.parsedFromDeps("nexttoclosure.js"))
+                .build(),
+            SimpleDependencyInfo.builder("nexttoclosure.js", SRC_PATH)
+                .setLoadFlags(ImmutableMap.of("module", "es6"))
+                .setProvides(ImmutableList.of("nexttoclosure.js"))
+                .build());
+    assertThat(result).isEqualTo(expected);
+  }
+
   public void testLoadFlags() {
     List<DependencyInfo> result = parser.parseFile(SRC_PATH, ""
         + "goog.addDependency('yes1', [], [], {'module': 'goog'});\n"