IDEA-76142: Gradle support - cannot update IDEA projects once one of build.gradle files changes

Don't process content roots that point to the unexisting files

plugins/gradle/src/org/jetbrains/plugins/gradle/diff/PlatformFacadeImpl.java

@@ -11,15 +11,11 @@ import com.intellij.openapi.roots.impl.libraries.ProjectLibraryTable;
 import com.intellij.openapi.roots.libraries.LibraryTable;
 import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.pom.java.LanguageLevel;
-import com.intellij.util.Function;
-import com.intellij.util.containers.ContainerUtil;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.plugins.gradle.model.intellij.ModuleAwareContentRoot;
 import org.jetbrains.plugins.gradle.util.GradleUtil;
 
-import java.util.Arrays;
-import java.util.Collection;
-import java.util.Collections;
+import java.util.*;
 
 /**
  * @author Denis Zhdanov
@@ -52,12 +48,14 @@ public class PlatformFacadeImpl implements PlatformFacade {
     if (entries == null) {
       return Collections.emptyList();
     }
-    return ContainerUtil.map(entries, new Function<ContentEntry, ModuleAwareContentRoot>() {
-      @Override
-      public ModuleAwareContentRoot fun(ContentEntry entry) {
-        return new ModuleAwareContentRoot(module, entry);
+    List<ModuleAwareContentRoot> result = new ArrayList<ModuleAwareContentRoot>();
+    for (ContentEntry entry : entries) {
+      final VirtualFile file = entry.getFile();
+      if (file != null) {
+        result.add(new ModuleAwareContentRoot(module, entry));
       }
-    });
+    }
+    return result;
   }
 
   @NotNull

plugins/gradle/src/org/jetbrains/plugins/gradle/model/intellij/ModuleAwareContentRoot.java

@@ -6,7 +6,6 @@ import com.intellij.openapi.roots.ExcludeFolder;
 import com.intellij.openapi.roots.SourceFolder;
 import com.intellij.openapi.vfs.VirtualFile;
 import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 
 /**
  * @author Denis Zhdanov
@@ -16,10 +15,19 @@ public class ModuleAwareContentRoot implements ContentEntry {
 
   @NotNull private final Module       myModule;
   @NotNull private final ContentEntry myDelegate;
+  @NotNull private final VirtualFile  myFile;
 
-  public ModuleAwareContentRoot(@NotNull Module module, @NotNull ContentEntry delegate) {
+  public ModuleAwareContentRoot(@NotNull Module module, @NotNull ContentEntry delegate) throws IllegalArgumentException {
     myDelegate = delegate;
     myModule = module;
+    final VirtualFile file = delegate.getFile();
+    if (file == null) {
+      throw new IllegalArgumentException(String.format(
+        "Detected attempt to create ModuleAwareContentRoot object for content root that points to the un-existing file - %s, module: %s",
+        delegate, module
+      ));
+    }
+    myFile = file;
   }
 
   @NotNull
@@ -27,10 +35,10 @@ public class ModuleAwareContentRoot implements ContentEntry {
     return myModule;
   }
 
+  @NotNull
   @Override
-  @Nullable
   public VirtualFile getFile() {
-    return myDelegate.getFile();
+    return myFile;
   }
 
   @Override