KT-1426 Implement "Optimize Imports" in plugin - do not remove imports for objects

compiler/frontend/src/org/jetbrains/jet/lang/psi/JetPsiUtil.java

@@ -145,49 +145,37 @@ public class JetPsiUtil {
     }
 
     @Nullable
-    public static FqName getFQName(@NotNull JetClassOrObject jetClass) {
-        if (jetClass.getName() == null) {
-            return null;
-        }
-
-        PsiElement parent = jetClass.getParent();
-        if (parent instanceof JetFile) {
-            return makeFQName(getFQName((JetFile) parent), jetClass);
-        }
-        while (parent instanceof JetClassBody) {
-            parent = parent.getParent();
-            if (parent instanceof JetObjectDeclaration && parent.getParent() instanceof JetClassObject) {
-                parent = parent.getParent().getParent();
+    public static FqName getFQName(JetNamedDeclaration namedDeclaration) {
+        if (namedDeclaration instanceof JetObjectDeclarationName) {
+            JetObjectDeclaration objectDeclaration = PsiTreeUtil.getParentOfType(namedDeclaration, JetObjectDeclaration.class);
+            if (objectDeclaration == null) {
+                return null;
             }
-        }
-        if (parent instanceof JetClassOrObject) {
-            return makeFQName(getFQName(((JetClassOrObject) parent)), jetClass);
-        }
-        return new FqName(jetClass.getName());
-    }
 
-    @Nullable
-    public static FqName getFQName(@NotNull JetNamedFunction jetNamedFunction) {
+            return getFQName(objectDeclaration);
+        }
 
-        String functionName = jetNamedFunction.getName();
+        String functionName = namedDeclaration.getName();
         if (functionName == null) {
             return null;
         }
 
-        @SuppressWarnings("unchecked")
-        PsiElement qualifiedElement = PsiTreeUtil.getParentOfType(
-                jetNamedFunction,
-                JetFile.class, JetClassOrObject.class, JetNamedFunction.class);
+        PsiElement parent = namedDeclaration.getParent();
+        if (parent instanceof JetClassBody) {
+            // One nesting to JetClassBody doesn't affect to qualified name
+            parent = parent.getParent();
+        }
 
-        FqName firstPart = FqName.ROOT;
-        if (qualifiedElement instanceof JetFile) {
-            firstPart = getFQName((JetFile) qualifiedElement);
+        FqName firstPart = null;
+        if (parent instanceof JetFile) {
+            firstPart = getFQName((JetFile) parent);
         }
-        else if (qualifiedElement instanceof JetClassOrObject) {
-            firstPart = getFQName((JetClassOrObject) qualifiedElement);
+        else if (parent instanceof JetNamedDeclaration) {
+            firstPart = getFQName((JetNamedDeclaration) parent);
         }
-        else if (qualifiedElement instanceof JetNamedFunction) {
-            firstPart = getFQName((JetNamedFunction) qualifiedElement);
+
+        if (firstPart == null) {
+            return null;
         }
 
         return firstPart.child(functionName);

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

@@ -130,7 +130,7 @@ public final class QualifiedNamesUtil {
     }
 
     public static boolean isImported(@NotNull ImportPath alreadyImported, @NotNull FqName fqName) {
-        if (alreadyImported.isAllUnder()) {
+        if (alreadyImported.isAllUnder() && !fqName.isRoot()) {
             return alreadyImported.fqnPart().equals(fqName.parent());
         }
 

idea/src/org/jetbrains/jet/plugin/editor/importOptimizer/JetImportOptimizer.java

@@ -83,9 +83,17 @@ public class JetImportOptimizer implements ImportOptimizer {
                         // Remove imports
                         List<JetImportDirective> imports = jetFile.getImportDirectives();
                         if (!imports.isEmpty()) {
-                            jetFile.deleteChildRange(
-                                    getWithPreviousWhitespaces(imports.get(0)),
-                                    getWithFollowedWhitespaces(imports.get(imports.size() - 1)));
+                            PsiElement firstForDelete = getWithPreviousWhitespaces(imports.get(0));
+                            PsiElement lastForDelete = getWithFollowedWhitespaces(imports.get(imports.size() - 1));
+
+                            // Should be found before deletion
+                            PsiElement elementBeforeImports = firstForDelete.getPrevSibling();
+
+                            jetFile.deleteChildRange(firstForDelete, lastForDelete);
+
+                            if (elementBeforeImports != null) {
+                                jetFile.addAfter(JetPsiFactory.createWhiteSpace(jetFile.getProject(), "\n"), elementBeforeImports);
+                            }
                         }
 
                         // Insert back only necessary imports in correct order
@@ -120,7 +128,7 @@ public class JetImportOptimizer implements ImportOptimizer {
         return false;
     }
 
-    public static Set<FqName> extractUsedQualifiedNames(JetFile jetFile) {
+    public static Set<FqName> extractUsedQualifiedNames(final JetFile jetFile) {
         final Set<FqName> usedQualifiedNames = new HashSet<FqName>();
         jetFile.accept(new JetVisitorVoid() {
             @Override
@@ -131,7 +139,9 @@ public class JetImportOptimizer implements ImportOptimizer {
 
             @Override
             public void visitReferenceExpression(JetReferenceExpression expression) {
-                if (PsiTreeUtil.getParentOfType(expression, JetImportDirective.class) == null) {
+                if (PsiTreeUtil.getParentOfType(expression, JetImportDirective.class) == null &&
+                        PsiTreeUtil.getParentOfType(expression, JetNamespaceHeader.class) == null) {
+
                     PsiReference reference = expression.getReference();
                     if (reference != null) {
                         List<PsiElement> references = new ArrayList<PsiElement>();
@@ -141,7 +151,7 @@ public class JetImportOptimizer implements ImportOptimizer {
                         }
 
                         if (references.isEmpty() && reference instanceof PsiPolyVariantReference) {
-                            for (ResolveResult resolveResult : ((PsiPolyVariantReference) reference).multiResolve(true)) {
+                            for (ResolveResult resolveResult : ((PsiPolyVariantReference)reference).multiResolve(true)) {
                                 references.add(resolveResult.getElement());
                             }
                         }
@@ -153,7 +163,6 @@ public class JetImportOptimizer implements ImportOptimizer {
                             }
                         }
                     }
-
                 }
 
                 super.visitReferenceExpression(expression);
@@ -166,18 +175,22 @@ public class JetImportOptimizer implements ImportOptimizer {
 
     @Nullable
     public static FqName getElementUsageFQName(PsiElement element) {
-        if (element instanceof JetClassOrObject) {
-            return JetPsiUtil.getFQName((JetClassOrObject) element);
+        if (element instanceof JetFile) {
+            return JetPsiUtil.getFQName((JetFile) element);
         }
-        if (element instanceof JetNamedFunction) {
-            return JetPsiUtil.getFQName((JetNamedFunction) element);
+
+        if (element instanceof JetNamedDeclaration) {
+            return JetPsiUtil.getFQName((JetNamedDeclaration) element);
         }
+
         if (element instanceof PsiClass) {
             String qualifiedName = ((PsiClass) element).getQualifiedName();
             if (qualifiedName != null) {
                 return new FqName(qualifiedName);
             }
         }
+
+        // TODO: Still problem with kotlin global properties imported from class files
         if (element instanceof PsiMethod) {
             PsiMethod method = (PsiMethod) element;
 
@@ -201,6 +214,10 @@ public class JetImportOptimizer implements ImportOptimizer {
             }
         }
 
+        if (element instanceof PsiPackage) {
+            return new FqName(((PsiPackage) element).getQualifiedName());
+        }
+
         return null;
     }
 

idea/testData/editor/optimizeImports/UnusedImports.kt

@@ -5,9 +5,15 @@ import java.net.HttpRetryException
 import java.util.ArrayList
 import kotlin.util.measureTimeMillis
 import java.util.HashMap
+import kotlin.test.asserter
+import kotlin.test.Asserter
+import kotlin.Assertions
 
 class Action {
     fun test() {
+        // val traait : Asserter = asserter
+        val traait : Asserter? = null
+        val objectImport : Assertions? = null
         measureTimeMillis({ println(HashMap<String, Int>().size()) })
         val test : ArrayList<Int>? = null
     }

idea/testData/editor/optimizeImports/UnusedImports_after.kt

@@ -1,9 +1,13 @@
 import java.util.ArrayList
 import java.util.HashMap
+import kotlin.test.Asserter
 import kotlin.util.measureTimeMillis
 
 class Action {
     fun test() {
+        // val traait : Asserter = asserter
+        val traait : Asserter? = null
+        val objectImport : Assertions? = null
         measureTimeMillis({ println(HashMap<String, Int>().size()) })
         val test : ArrayList<Int>? = null
     }