add explicit type parameters available for conditional expr (IDEA-1179)

java/java-impl/src/com/intellij/codeInsight/daemon/impl/analysis/HighlightUtil.java

@@ -490,6 +490,7 @@ public class HighlightUtil {
     }
     if (expression != null && lType != null) {
       QuickFixAction.registerQuickFixAction(highlightInfo, new WrapExpressionFix(lType, expression));
+      AddTypeArgumentsConditionalFix.register(highlightInfo, expression, lType);
     }
     ChangeNewOperatorTypeFix.register(highlightInfo, expression, lType);
     return highlightInfo;

java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/AddTypeArgumentsConditionalFix.java

@@ -0,0 +1,153 @@
+/*
+ * Copyright 2000-2012 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.codeInsight.daemon.impl.quickfix;
+
+import com.intellij.codeInsight.daemon.impl.HighlightInfo;
+import com.intellij.codeInsight.intention.IntentionAction;
+import com.intellij.openapi.diagnostic.Logger;
+import com.intellij.openapi.editor.Editor;
+import com.intellij.openapi.project.Project;
+import com.intellij.openapi.util.text.StringUtil;
+import com.intellij.psi.*;
+import com.intellij.psi.impl.source.resolve.DefaultParameterTypeInferencePolicy;
+import com.intellij.psi.util.TypeConversionUtil;
+import com.intellij.refactoring.util.RefactoringUtil;
+import com.intellij.util.Function;
+import com.intellij.util.IncorrectOperationException;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * User: anna
+ * Date: 2/17/12
+ */
+public class AddTypeArgumentsConditionalFix implements IntentionAction {
+  private static final Logger LOG = Logger.getInstance("#" + AddTypeArgumentsConditionalFix.class.getName());
+
+  private final PsiSubstitutor mySubstitutor;
+  private final PsiMethodCallExpression myExpression;
+  private final PsiMethod myMethod;
+
+  public AddTypeArgumentsConditionalFix(PsiSubstitutor substitutor, PsiMethodCallExpression expression, PsiMethod method) {
+    mySubstitutor = substitutor;
+    myExpression = expression;
+    myMethod = method;
+  }
+
+  @NotNull
+  @Override
+  public String getText() {
+    return "Add explicit type arguments";
+  }
+
+  @NotNull
+  @Override
+  public String getFamilyName() {
+    return getText();
+  }
+
+  @Override
+  public boolean isAvailable(@NotNull Project project, Editor editor, PsiFile file) {
+    if (mySubstitutor.isValid() && myExpression.isValid() && myMethod.isValid()) {
+      return true;
+    }
+    return false;
+  }
+
+  @Override
+  public void invoke(@NotNull Project project, Editor editor, PsiFile file) throws IncorrectOperationException {
+    final PsiTypeParameter[] typeParameters = myMethod.getTypeParameters();
+    final String typeArguments = "<" + StringUtil.join(typeParameters, new Function<PsiTypeParameter, String>() {
+      @Override
+      public String fun(PsiTypeParameter parameter) {
+        final PsiType substituteTypeParam = mySubstitutor.substitute(parameter);
+        LOG.assertTrue(substituteTypeParam != null);
+        return substituteTypeParam.getCanonicalText();
+      }
+    }, ", ") + ">";
+    final PsiExpression expression = myExpression.getMethodExpression().getQualifierExpression();
+    String withTypeArgsText;
+    if (expression != null) {
+      withTypeArgsText = expression.getText();
+    }
+    else {
+      if (RefactoringUtil.isInStaticContext(myExpression, null) || myMethod.hasModifierProperty(PsiModifier.STATIC)) {
+        final PsiClass aClass = myMethod.getContainingClass();
+        LOG.assertTrue(aClass != null);
+        withTypeArgsText = aClass.getQualifiedName();
+      }
+      else {
+        withTypeArgsText = "this";
+      }
+    }
+    withTypeArgsText += "." + typeArguments + myExpression.getMethodExpression().getReferenceName();
+    final PsiExpression withTypeArgs = JavaPsiFacade.getElementFactory(project).createExpressionFromText(withTypeArgsText + myExpression.getArgumentList().getText(), myExpression);
+    myExpression.replace(withTypeArgs);
+  }
+
+  @Override
+  public boolean startInWriteAction() {
+    return true;
+  }
+
+  public static void register(HighlightInfo highlightInfo, PsiExpression expression, PsiType lType) {
+    if (expression instanceof PsiConditionalExpression) {
+      final PsiExpression thenExpression = ((PsiConditionalExpression)expression).getThenExpression();
+      final PsiExpression elseExpression = ((PsiConditionalExpression)expression).getElseExpression();
+      if (thenExpression != null && elseExpression != null) {
+        final PsiType thenType = thenExpression.getType();
+        final PsiType elseType = elseExpression.getType();
+        if (thenType != null && elseType != null) {
+          final boolean thenAssignable = TypeConversionUtil.isAssignable(lType, thenType);
+          final boolean elseAssignable = TypeConversionUtil.isAssignable(lType, elseType);
+          if (!thenAssignable && thenExpression instanceof PsiMethodCallExpression) {
+            inferTypeArgs(highlightInfo, lType, thenExpression);
+          }
+          if (!elseAssignable && elseExpression instanceof PsiMethodCallExpression) {
+            inferTypeArgs(highlightInfo, lType, elseExpression);
+          }
+        }
+      }
+    }
+  }
+
+  private static void inferTypeArgs(HighlightInfo highlightInfo, PsiType lType, PsiExpression thenExpression) {
+    final JavaResolveResult result = ((PsiMethodCallExpression)thenExpression).resolveMethodGenerics();
+    final PsiMethod method = (PsiMethod)result.getElement();
+    if (method != null) {
+      final PsiType returnType = method.getReturnType();
+      final PsiClass aClass = method.getContainingClass();
+      if (returnType != null && aClass != null && aClass.getQualifiedName() != null) {
+        final JavaPsiFacade javaPsiFacade = JavaPsiFacade.getInstance(method.getProject());
+        final PsiDeclarationStatement variableDeclarationStatement =
+          javaPsiFacade.getElementFactory().createVariableDeclarationStatement("xxx", lType, thenExpression);
+        final PsiExpression initializer =
+          ((PsiLocalVariable)variableDeclarationStatement.getDeclaredElements()[0]).getInitializer();
+        LOG.assertTrue(initializer != null);
+
+        final PsiSubstitutor substitutor = javaPsiFacade.getResolveHelper()
+          .inferTypeArguments(method.getTypeParameters(), method.getParameterList().getParameters(),
+                              ((PsiMethodCallExpression)thenExpression).getArgumentList().getExpressions(), PsiSubstitutor.EMPTY,
+                              initializer, DefaultParameterTypeInferencePolicy.INSTANCE);
+        PsiType substitutedType = substitutor.substitute(returnType);
+        if (substitutedType != null && TypeConversionUtil.isAssignable(lType, substitutedType)) {
+          QuickFixAction.registerQuickFixAction(highlightInfo,
+                                                thenExpression.getTextRange(),
+                                                new AddTypeArgumentsConditionalFix(substitutor, (PsiMethodCallExpression)thenExpression, method), null);
+        }
+      }
+    }
+  }
+}

java/java-impl/src/com/intellij/refactoring/util/RefactoringUtil.java

@@ -80,7 +80,7 @@ public class RefactoringUtil {
     return Comparing.equal(virtualFile, sourceRootForFile);
   }
 
-  public static boolean isInStaticContext(PsiElement element, final PsiClass aClass) {
+  public static boolean isInStaticContext(PsiElement element, @Nullable final PsiClass aClass) {
     return PsiUtil.getEnclosingStaticElement(element, aClass) != null;
   }