KT-1051 Java interoperability completion - fix java subpackages

compiler/frontend/src/org/jetbrains/jet/util/QualifiedNamesUtil.java

@@ -15,12 +15,12 @@ public final class QualifiedNamesUtil {
         return subpackageName.equals(packageName) ||
                (subpackageName.startsWith(packageName) && subpackageName.charAt(packageName.length()) == '.');
     }
-    
+
     public static boolean isShortNameForFQN(@NotNull final String name, @NotNull final String fqn) {
         return fqn.equals(name) ||
                (fqn.endsWith(name) && fqn.charAt(fqn.length() - name.length() - 1) == '.');
     }
-    
+
     public static boolean isOneSegmentFQN(@NotNull final String fqn) {
         if (fqn.isEmpty()) {
             return false;
@@ -30,14 +30,20 @@ public final class QualifiedNamesUtil {
     }
 
     @NotNull
-    public static String fqnToShortName(@NotNull String fqName) {
-        int lastDotIndex = fqName.lastIndexOf('.');
+    public static String fqnToShortName(@NotNull String fqn) {
+        return getLastSegment(fqn);
+    }
 
-        if (lastDotIndex != -1) {
-            return fqName.substring(lastDotIndex + 1, fqName.length());
-        }
+    @NotNull
+    public static String getLastSegment(@NotNull String fqn) {
+        int lastDotIndex = fqn.lastIndexOf('.');
+        return (lastDotIndex != -1) ? fqn.substring(lastDotIndex + 1, fqn.length()) : fqn;
+    }
 
-        return fqName;
+    @NotNull
+    public static String getFirstSegment(@NotNull String fqn) {
+        int dotIndex = fqn.indexOf('.');
+        return (dotIndex != -1) ? fqn.substring(0, dotIndex) : fqn;
     }
 
     @NotNull
@@ -55,17 +61,43 @@ public final class QualifiedNamesUtil {
         return first + "." + second;
     }
 
-//    private static String subPackageName(String packageName, String packageFQN) {
-//        if (!isInPackage(packageName, packageFQN)) {
-//            return null;
-//        }
-//
-//        int nextDotIndex = packageFQN.indexOf('.', (packageName + ".").length());
-//
-//        if (nextDotIndex != -1) {
-//            return packageFQN.substring((packageName + ".").length(), nextDotIndex);
-//        }
-//
-//        return packageFQN.substring((packageName + ".").length());
-//    }
-}
+    /**
+     * Get tail part of the full fqn by subtracting head part.
+     *
+     * @param headFQN
+     * @param fullFQN
+     * @return tail fqn. If first part is not a begging of the full fqn, fullFQN will be returned.
+     */
+    @NotNull
+    public static String tail(@NotNull String headFQN, @NotNull String fullFQN) {
+        if (!isSubpackageOf(fullFQN, headFQN)) {
+            return fullFQN;
+        }
+
+        return fullFQN.equals(headFQN) ?
+               "" :
+               fullFQN.substring(headFQN.length() + 1); // (headFQN + '.').length
+    }
+
+    /**
+     * Add one segment of nesting to given qualified name according to the full qualified name.
+     *
+     * @param fqn
+     * @param fullFQN
+     * @return qualified name with one more segment or null if fqn is not head part of fullFQN or there's no additional segment.
+     */
+    @Nullable
+    public static String plusOneSegment(String fqn, String fullFQN) {
+        if (!isSubpackageOf(fullFQN, fqn)) {
+            return null;
+        }
+
+        final String nextSegment = getFirstSegment(tail(fqn, fullFQN));
+
+        if (isOneSegmentFQN(nextSegment)) {
+            return combine(fqn, nextSegment);
+        }
+
+        return null;
+    }
+}

compiler/jet.as.java.psi/src/org/jetbrains/jet/asJava/JavaElementFinder.java

@@ -9,7 +9,6 @@ import com.intellij.psi.PsiClass;
 import com.intellij.psi.PsiElementFinder;
 import com.intellij.psi.PsiManager;
 import com.intellij.psi.PsiPackage;
-import com.intellij.psi.impl.file.PsiPackageImpl;
 import com.intellij.psi.search.GlobalSearchScope;
 import com.intellij.util.SmartList;
 import org.jetbrains.annotations.NotNull;
@@ -142,7 +141,7 @@ public class JavaElementFinder extends PsiElementFinder {
 
         for (JetFile psiFile : psiFiles) {
             if (JetPsiUtil.getFQName(psiFile).startsWith(qualifiedName)) {
-                return new PsiPackageImpl(psiFile.getManager(), qualifiedName);
+                return new JetLightPackage(psiManager, qualifiedName);
             }
         }
 
@@ -159,10 +158,9 @@ public class JavaElementFinder extends PsiElementFinder {
         for (JetFile psiFile : psiFiles) {
             String jetRootNamespace = JetPsiUtil.getFQName(psiFile);
 
-            if (QualifiedNamesUtil.isSubpackageOf(jetRootNamespace, psiPackage.getQualifiedName())) {
-
-                // TODO: wrong package here
-                answer.add(new JetLightPackage(psiFile.getManager(), jetRootNamespace));
+            final String subPackageFQN = QualifiedNamesUtil.plusOneSegment(psiPackage.getQualifiedName(), jetRootNamespace);
+            if (subPackageFQN != null) {
+                answer.add(new JetLightPackage(psiManager, subPackageFQN));
             }
         }
 

compiler/jet.as.java.psi/src/org/jetbrains/jet/asJava/JetLightClass.java

@@ -34,6 +34,7 @@ import org.jetbrains.jet.lang.resolve.BindingContext;
 import org.jetbrains.jet.lang.resolve.java.AnalyzerFacade;
 import org.jetbrains.jet.lang.resolve.java.JetJavaMirrorMarker;
 import org.jetbrains.jet.plugin.JetLanguage;
+import org.jetbrains.jet.util.QualifiedNamesUtil;
 
 import javax.swing.*;
 import java.util.Collections;
@@ -55,8 +56,7 @@ public class JetLightClass extends AbstractLightClass implements JetJavaMirrorMa
 
     @Override
     public String getName() {
-        int idx = qualifiedName.lastIndexOf('.');
-        return idx > 0 ? qualifiedName.substring(idx + 1) : qualifiedName;
+        return QualifiedNamesUtil.fqnToShortName(qualifiedName);
     }
 
     @Override
@@ -72,6 +72,7 @@ public class JetLightClass extends AbstractLightClass implements JetJavaMirrorMa
     @Override
     public PsiClass getDelegate() {
         if (delegate == null) {
+            // TODO: What is the reason for this?
             delegate = findClass(qualifiedName, getStub());
             if (delegate == null) {
                 delegate = findClass(qualifiedName, getStub());

compiler/jet.as.java.psi/src/org/jetbrains/jet/asJava/JetLightPackage.java

@@ -1,9 +1,12 @@
 package org.jetbrains.jet.asJava;
 
+import com.intellij.psi.PsiElement;
 import com.intellij.psi.PsiManager;
 import com.intellij.psi.impl.file.PsiPackageImpl;
 
 /**
+ * TODO: make more accurate wrapper
+ *
  * @author Nikolay Krasko
  */
 public class JetLightPackage extends PsiPackageImpl {
@@ -11,8 +14,14 @@ public class JetLightPackage extends PsiPackageImpl {
         super(manager, qualifiedName);
     }
 
+    @Override
+    public PsiElement copy() {
+        return new JetLightPackage(getManager(), getQualifiedName());
+    }
+
     @Override
     public boolean isValid() {
-        return true;
+        // TODO: invalidate properly
+        return super.isValid();
     }
 }

idea/testData/completion/injava/JetSubpackage.java

@@ -4,4 +4,8 @@ public class Testing {
     }
 }
 
-// EXIST: jet
+// EXIST: jet1
+// ABSENT: jet2
+
+// Only two proposals expected
+// NUMBER: 1

idea/testData/completion/injava/JetSubpackage.kt

@@ -1,4 +1,4 @@
-package testing.jet
+package testing.jet1.jet2
 
 fun somefun() {
 }