Provide a way to exclude directories under project sdk roots

platform/projectModel-impl/src/com/intellij/openapi/roots/impl/DirectoryIndexExcludePolicy.java

@@ -33,6 +33,11 @@ public interface DirectoryIndexExcludePolicy {
   @NotNull
   VirtualFile[] getExcludeRootsForProject();
 
+  @NotNull
+  default VirtualFile[] getExcludeRootsForProjectSdk() {
+    return VirtualFile.EMPTY_ARRAY;
+  }
+
   @NotNull
   VirtualFilePointer[] getExcludeRootsForModule(@NotNull ModuleRootModel rootModel);
 

platform/projectModel-impl/src/com/intellij/openapi/roots/impl/RootIndex.java

@@ -204,6 +204,7 @@ public class RootIndex {
     }
     for (DirectoryIndexExcludePolicy policy : Extensions.getExtensions(DirectoryIndexExcludePolicy.EP_NAME, project)) {
       info.excludedFromProject.addAll(ContainerUtil.filter(policy.getExcludeRootsForProject(), file -> ensureValid(file, policy)));
+      info.excludedFromProjectSdk.addAll(ContainerUtil.filter(policy.getExcludeRootsForProjectSdk(), file -> ensureValid(file, policy)));
     }
     for (UnloadedModuleDescription description : moduleManager.getUnloadedModuleDescriptions()) {
       for (VirtualFilePointer pointer : description.getContentRoots()) {
@@ -641,6 +642,7 @@ public class RootIndex {
     @NotNull final MultiMap<VirtualFile, Library> classOfLibraries = MultiMap.createSmart();
     @NotNull final MultiMap<VirtualFile, /*Library|SyntheticLibrary*/ Object> sourceOfLibraries = MultiMap.createSmart();
     @NotNull final Set<VirtualFile> excludedFromProject = ContainerUtil.newHashSet();
+    @NotNull final Set<VirtualFile> excludedFromProjectSdk = ContainerUtil.newHashSet();
     @NotNull final Map<VirtualFile, Module> excludedFromModule = ContainerUtil.newHashMap();
     @NotNull final Map<VirtualFile, FileTypeAssocTable<Boolean>> excludeFromContentRootTables = ContainerUtil.newHashMap();
     @NotNull final Map<VirtualFile, String> packagePrefix = ContainerUtil.newHashMap();
@@ -654,6 +656,7 @@ public class RootIndex {
       result.addAll(excludedFromLibraries.keySet());
       result.addAll(excludedFromModule.keySet());
       result.addAll(excludedFromProject);
+      result.addAll(excludedFromProjectSdk);
       return result;
     }
 
@@ -862,7 +865,9 @@ public class RootIndex {
     Pair<VirtualFile, Collection<Object>> libraryClassRootInfo = info.findLibraryRootInfo(hierarchy, false);
     VirtualFile libraryClassRoot = libraryClassRootInfo != null ? libraryClassRootInfo.first : null;
 
-    boolean inProject = moduleContentRoot != null || libraryClassRoot != null || librarySourceRoot != null;
+    boolean inProject = moduleContentRoot != null ||
+                        ( (libraryClassRoot != null || librarySourceRoot != null) && !info.excludedFromProjectSdk.contains(root));
+
     VirtualFile nearestContentRoot;
     if (inProject) {
       nearestContentRoot = moduleContentRoot;

python/ide/src/com/jetbrains/python/PyDirectoryIndexExcludePolicy.java

@@ -16,6 +16,7 @@
 package com.jetbrains.python;
 
 import com.google.common.collect.Lists;
+import com.google.common.collect.Sets;
 import com.intellij.openapi.module.Module;
 import com.intellij.openapi.module.ModuleManager;
 import com.intellij.openapi.project.Project;
@@ -30,11 +31,13 @@ import com.jetbrains.python.sdk.PythonSdkType;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.List;
+import java.util.Set;
 
 /**
  * @author traff
  */
 public class PyDirectoryIndexExcludePolicy implements DirectoryIndexExcludePolicy {
+  private final static String[] SITE_PACKAGES = new String[]{"site-packages", "dist-packages"};
 
   private final Project myProject;
 
@@ -53,13 +56,24 @@ public class PyDirectoryIndexExcludePolicy implements DirectoryIndexExcludePolic
       }
     }
 
+    return result.toArray(new VirtualFile[result.size()]);
+  }
+
+  @NotNull
+  @Override
+  public VirtualFile[] getExcludeRootsForProjectSdk() {
+    List<VirtualFile> result = Lists.newArrayList();
+
     for (Module m : ModuleManager.getInstance(myProject).getModules()) {
       Sdk sdk = PythonSdkType.findPythonSdk(m);
       if (sdk != null) {
+        Set<VirtualFile> roots = Sets.newHashSet(sdk.getRootProvider().getFiles(OrderRootType.CLASSES));
         for (VirtualFile dir : sdk.getRootProvider().getFiles(OrderRootType.CLASSES)) {
-          VirtualFile sitePackages = dir.findChild("site-packages");
-          if (sitePackages != null) {
-            result.add(sitePackages);
+          for (String name : SITE_PACKAGES) {
+            VirtualFile sitePackages = dir.findChild(name);
+            if (sitePackages != null && !roots.contains(sitePackages)) {
+              result.add(sitePackages);
+            }
           }
         }
       }
@@ -71,8 +85,8 @@ public class PyDirectoryIndexExcludePolicy implements DirectoryIndexExcludePolic
   @NotNull
   @Override
   public VirtualFilePointer[] getExcludeRootsForModule(@NotNull ModuleRootModel rootModel) {
-    
-    
+
+
     return VirtualFilePointer.EMPTY_ARRAY;
   }
 }