From 4c72b12c6a50b380babfcd91c3ebe0dafd471eec Mon Sep 17 00:00:00 2001
From: Dmitry Batkovich <dmitry.batkovich@jetbrains.com>
Date: Mon, 24 Oct 2016 17:46:45 +0300
Subject: [PATCH] function expression searcher: find most likely files only
 among of files where occurrences was found

---
 .../JavaFunctionalExpressionSearcher.java     | 29 ++++++++++---------
 .../lambda/FindFunctionalInterfaceTest.java   |  2 +-
 2 files changed, 17 insertions(+), 14 deletions(-)

diff --git a/java/java-indexing-impl/src/com/intellij/psi/impl/search/JavaFunctionalExpressionSearcher.java b/java/java-indexing-impl/src/com/intellij/psi/impl/search/JavaFunctionalExpressionSearcher.java
index e401087d5a86..b23e14b0fb01 100644
--- a/java/java-indexing-impl/src/com/intellij/psi/impl/search/JavaFunctionalExpressionSearcher.java
+++ b/java/java-indexing-impl/src/com/intellij/psi/impl/search/JavaFunctionalExpressionSearcher.java
@@ -84,7 +84,7 @@ public class JavaFunctionalExpressionSearcher extends QueryExecutorBase<PsiFunct
     PsiManager manager = ReadAction.compute(() -> p.getElementToSearch().getManager());
     manager.startBatchFilesProcessingMode();
     try {
-      processOffsets(descriptors, (file, offsets) -> {
+      processOffsets(descriptors, project, (file, offsets) -> {
         fileCount.incrementAndGet();
         exprCount.addAndGet(offsets.size());
         return processFile(consumer, descriptors, file, offsets);
@@ -99,9 +99,9 @@ public class JavaFunctionalExpressionSearcher extends QueryExecutorBase<PsiFunct
   }
 
   @TestOnly
-  public static Set<VirtualFile> getFilesToSearchInPsi(PsiClass samClass) {
+  public static Set<VirtualFile> getFilesToSearchInPsi(PsiClass samClass, Project project) {
     Set<VirtualFile> result = new HashSet<>();
-    processOffsets(calcDescriptors(new SearchParameters(samClass, samClass.getUseScope())), (file, offsets) -> result.add(file));
+    processOffsets(calcDescriptors(new SearchParameters(samClass, samClass.getUseScope())), project, (file, offsets) -> result.add(file));
     return result;
   }
 
@@ -134,8 +134,9 @@ public class JavaFunctionalExpressionSearcher extends QueryExecutorBase<PsiFunct
   }
 
   @NotNull
-  private static Set<VirtualFile> getLikelyFiles(List<SamDescriptor> descriptors) {
-    return JBIterable.from(descriptors).flatMap(SamDescriptor::getMostLikelyFiles).toSet();
+  private static Set<VirtualFile> getLikelyFiles(List<SamDescriptor> descriptors, Collection<VirtualFile> candidateFiles, Project project) {
+    final GlobalSearchScope candidateFilesScope = GlobalSearchScope.filesScope(project, candidateFiles);
+    return JBIterable.from(descriptors).flatMap(descriptor -> descriptor.getMostLikelyFiles(candidateFilesScope)).toSet();
   }
 
   @NotNull
@@ -156,12 +157,14 @@ public class JavaFunctionalExpressionSearcher extends QueryExecutorBase<PsiFunct
     return result;
   }
 
-  private static void processOffsets(List<SamDescriptor> descriptors, PairProcessor<VirtualFile, List<Integer>> processor) {
+  private static void processOffsets(List<SamDescriptor> descriptors, Project project, PairProcessor<VirtualFile, List<Integer>> processor) {
     if (descriptors.isEmpty()) return;
 
     List<PsiClass> samClasses = ContainerUtil.map(descriptors, d -> d.samClass);
     MultiMap<VirtualFile, FunExprOccurrence> allCandidates = getAllOccurrences(descriptors);
-    for (VirtualFile vFile : putLikelyFilesFirst(descriptors, allCandidates.keySet())) {
+    if (allCandidates.isEmpty()) return;
+
+    for (VirtualFile vFile : putLikelyFilesFirst(descriptors, allCandidates.keySet(), project)) {
       List<FunExprOccurrence> toLoad = filterInapplicable(samClasses, vFile, allCandidates.get(vFile));
       if (!toLoad.isEmpty()) {
         LOG.trace("To load " + vFile.getPath() + " with values: " + toLoad);
@@ -173,9 +176,9 @@ public class JavaFunctionalExpressionSearcher extends QueryExecutorBase<PsiFunct
   }
 
   @NotNull
-  private static Set<VirtualFile> putLikelyFilesFirst(List<SamDescriptor> descriptors, Set<VirtualFile> allFiles) {
-    Set<VirtualFile> orderedFiles = new LinkedHashSet<>(allFiles);
-    orderedFiles.retainAll(getLikelyFiles(descriptors));
+  private static Set<VirtualFile> putLikelyFilesFirst(List<SamDescriptor> descriptors, Set<VirtualFile> allFiles, Project project) {
+    Set<VirtualFile> orderedFiles = new LinkedHashSet<>(allFiles.size());
+    orderedFiles.addAll(getLikelyFiles(descriptors, allFiles, project));
     orderedFiles.addAll(allFiles);
     return orderedFiles;
   }
@@ -306,7 +309,7 @@ public class JavaFunctionalExpressionSearcher extends QueryExecutorBase<PsiFunct
     }
 
     @NotNull
-    private Set<VirtualFile> getMostLikelyFiles() {
+    private Set<VirtualFile> getMostLikelyFiles(GlobalSearchScope searchScope) {
       Set<VirtualFile> files = ContainerUtil.newLinkedHashSet();
       ReadAction.run(() -> {
         if (!samClass.isValid()) return;
@@ -317,7 +320,7 @@ public class JavaFunctionalExpressionSearcher extends QueryExecutorBase<PsiFunct
 
         Set<String> likelyNames = ContainerUtil.newLinkedHashSet(className);
         StubIndex.getInstance().processElements(JavaMethodParameterTypesIndex.getInstance().getKey(), className,
-                                                project, effectiveUseScope, PsiMethod.class, method -> {
+                                                project, searchScope, PsiMethod.class, method -> {
             ProgressManager.checkCanceled();
             likelyNames.add(method.getName());
             return true;
@@ -326,7 +329,7 @@ public class JavaFunctionalExpressionSearcher extends QueryExecutorBase<PsiFunct
         PsiSearchHelperImpl helper = (PsiSearchHelperImpl)PsiSearchHelper.SERVICE.getInstance(project);
         Processor<VirtualFile> processor = Processors.cancelableCollectProcessor(files);
         for (String word : likelyNames) {
-          helper.processFilesWithText(effectiveUseScope, UsageSearchContext.IN_CODE, true, word, processor);
+          helper.processFilesWithText(searchScope, UsageSearchContext.IN_CODE, true, word, processor);
         }
       });
       return files;
diff --git a/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/FindFunctionalInterfaceTest.java b/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/FindFunctionalInterfaceTest.java
index c02e3c770fec..801acf286bbb 100644
--- a/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/FindFunctionalInterfaceTest.java
+++ b/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/FindFunctionalInterfaceTest.java
@@ -172,7 +172,7 @@ public class FindFunctionalInterfaceTest extends LightCodeInsightFixtureTestCase
                        "}");
 
     assertSize(1, FunctionalExpressionSearch.search(sam).findAll());
-    for (VirtualFile file : JavaFunctionalExpressionSearcher.getFilesToSearchInPsi(sam)) {
+    for (VirtualFile file : JavaFunctionalExpressionSearcher.getFilesToSearchInPsi(sam, getProject())) {
       assertFalse(file.getName(), file.getName().startsWith("_"));
     }
   }