diff --git a/platform/lang-impl/src/com/intellij/util/indexing/roots/ModuleIndexableFilesIteratorImpl.kt b/platform/lang-impl/src/com/intellij/util/indexing/roots/ModuleIndexableFilesIteratorImpl.kt
index f5c87e7929a5..c088bcea5780 100644
--- a/platform/lang-impl/src/com/intellij/util/indexing/roots/ModuleIndexableFilesIteratorImpl.kt
+++ b/platform/lang-impl/src/com/intellij/util/indexing/roots/ModuleIndexableFilesIteratorImpl.kt
@@ -16,7 +16,7 @@ import com.intellij.util.indexing.roots.origin.IndexingUrlRootHolder
 import com.intellij.util.indexing.roots.origin.ModuleRootOriginImpl
 
 /**
- * @param rootHolder is null when iterator should just iterate all files in module, no explicit root list
+ * @param rootHolder is null when iterator should just iterate all files in [module], no explicit root list
  */
 internal class ModuleIndexableFilesIteratorImpl private constructor(private val module: Module,
                                                                     rootHolder: IndexingRootHolder?,
@@ -34,10 +34,10 @@ internal class ModuleIndexableFilesIteratorImpl private constructor(private val
     fun createIterators(module: Module, urlRoots: IndexingUrlRootHolder): Collection<IndexableFilesIterator> {
       val roots = urlRoots.toRootHolder()
       if (roots.isEmpty()) return emptyList()
-      // 100 is a totally magic constant here, designed to help Rider to avoid indexing all non-recursive roots with one iterator => on a
-      // single thread
+      // 100 is a totally magic constant here, designed to help Rider to avoid indexing all non-recursive roots with one iterator,
+      // which results in indexing on a single thread
       if (roots.size() > 100) {
-        return roots.split(100).map { rootSublists -> ModuleIndexableFilesIteratorImpl(module, rootSublists, true) }
+        return roots.split(100).map { rootSublist -> ModuleIndexableFilesIteratorImpl(module, rootSublist, true) }
       }
       return setOf(ModuleIndexableFilesIteratorImpl(module, roots, true))
     }
@@ -99,7 +99,7 @@ internal class ModuleIndexableFilesIteratorImpl private constructor(private val
       }
       return nonRecursiveRoots?.all { root ->
         if (runReadAction { index.isInContent(root) } && fileFilter.accept(root)) fileIterator.processFile(root) else true
-      } ?: true
+      } != false
     }
   }