PyMakeFunctionReturnTypeQuickFix.java

/*
 * Copyright 2000-2016 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.jetbrains.python.inspections.quickfix;

import com.intellij.codeInspection.LocalQuickFix;
import com.intellij.codeInspection.ProblemDescriptor;
import com.intellij.openapi.project.Project;
import com.intellij.psi.PsiComment;
import com.intellij.psi.SmartPointerManager;
import com.intellij.psi.SmartPsiElementPointer;
import com.jetbrains.python.PyBundle;
import com.jetbrains.python.documentation.PythonDocumentationProvider;
import com.jetbrains.python.psi.*;
import com.jetbrains.python.psi.types.TypeEvalContext;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

/**
 * @author lada
 */
public class PyMakeFunctionReturnTypeQuickFix implements LocalQuickFix {
  private final SmartPsiElementPointer<PyFunction> myFunction;
  private final SmartPsiElementPointer<PyAnnotation> myAnnotation;
  private final SmartPsiElementPointer<PsiComment> myTypeCommentAnnotation;
  private final String myReturnTypeName;

  public PyMakeFunctionReturnTypeQuickFix(@NotNull PyFunction function, @Nullable String returnTypeName, @NotNull TypeEvalContext context) {
    final SmartPointerManager manager = SmartPointerManager.getInstance(function.getProject());
    myFunction = manager.createSmartPsiElementPointer(function);
    PyAnnotation annotation = function.getAnnotation();
    myAnnotation = annotation != null ? manager.createSmartPsiElementPointer(annotation) : null;
    PsiComment typeCommentAnnotation = function.getTypeComment();
    myTypeCommentAnnotation = typeCommentAnnotation != null ? manager.createSmartPsiElementPointer(typeCommentAnnotation) : null;
    myReturnTypeName = (returnTypeName == null) ? PythonDocumentationProvider.getTypeName(function.getReturnStatementType(context), context) : returnTypeName;
  }

  @NotNull
  public String getName() {
    PyFunction function = myFunction.getElement();
    String functionName = function != null ? function.getName() : "function";
    return PyBundle.message("QFIX.NAME.make.$0.return.$1", functionName, myReturnTypeName);
  }

  @NotNull
  public String getFamilyName() {
    return PyBundle.message("QFIX.NAME.make.$0.return.$1", "function", "inferred type");
  }

  public void applyFix(@NotNull Project project, @NotNull ProblemDescriptor descriptor) {
    PyElementGenerator elementGenerator = PyElementGenerator.getInstance(project);
    if (myAnnotation != null) {
      final PyAnnotation annotation = myAnnotation.getElement();
      if (annotation != null) {
        final PyExpression annotationExpr = annotation.getValue();
        if (annotationExpr == null) return;
        annotationExpr.replace(elementGenerator.createExpressionFromText(LanguageLevel.PYTHON30, myReturnTypeName));
      }
    }
    else if (myTypeCommentAnnotation != null) {
      final PsiComment typeComment = myTypeCommentAnnotation.getElement();
      if (typeComment != null) {
        final StringBuilder typeCommentAnnotation = new StringBuilder(typeComment.getText());
        typeCommentAnnotation.delete(typeCommentAnnotation.indexOf("->"), typeCommentAnnotation.length());
        typeCommentAnnotation.append("-> ").append(myReturnTypeName);
        final PsiComment newTypeComment = elementGenerator.createFromText(LanguageLevel.PYTHON27, PsiComment.class, typeCommentAnnotation.toString());
        typeComment.replace(newTypeComment);
      }
    }
  }
}