com.google.errorprone.bugpatterns.javadoc.Utils Maven / Gradle / Ivy
/*
* Copyright 2018 The Error Prone Authors.
*
* 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.google.errorprone.bugpatterns.javadoc;
import static com.google.errorprone.names.LevenshteinEditDistance.getEditDistance;
import com.google.errorprone.VisitorState;
import com.google.errorprone.fixes.FixedPosition;
import com.google.errorprone.fixes.SuggestedFix;
import com.google.errorprone.util.ASTHelpers;
import com.sun.source.doctree.DocCommentTree;
import com.sun.source.doctree.DocTree;
import com.sun.source.tree.CompilationUnitTree;
import com.sun.source.tree.Tree;
import com.sun.source.util.DocSourcePositions;
import com.sun.source.util.DocTreePath;
import com.sun.tools.javac.api.JavacTrees;
import com.sun.tools.javac.tree.DCTree.DCDocComment;
import com.sun.tools.javac.tree.JCTree;
import com.sun.tools.javac.tree.JCTree.JCCompilationUnit;
import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
import com.sun.tools.javac.util.Position;
import java.util.Optional;
import javax.annotation.Nullable;
/** Common utility methods for fixing Javadocs. */
final class Utils {
static Optional getBestMatch(String to, int maxEditDistance, Iterable choices) {
String bestMatch = null;
int minDistance = Integer.MAX_VALUE;
for (String choice : choices) {
int distance = getEditDistance(to, choice);
if (distance < minDistance && distance < maxEditDistance) {
bestMatch = choice;
minDistance = distance;
}
}
return Optional.ofNullable(bestMatch);
}
static DCDocComment getDocComment(VisitorState state, Tree tree) {
return ((JCCompilationUnit) state.getPath().getCompilationUnit())
.docComments.getCommentTree((JCTree) tree);
}
static SuggestedFix replace(DocTree docTree, String replacement, VisitorState state) {
DocSourcePositions positions = JavacTrees.instance(state.context).getSourcePositions();
CompilationUnitTree compilationUnitTree = state.getPath().getCompilationUnit();
int startPos = getStartPosition(docTree, state);
int endPos =
(int) positions.getEndPosition(compilationUnitTree, getDocCommentTree(state), docTree);
if (endPos == Position.NOPOS) {
return SuggestedFix.emptyFix();
}
return SuggestedFix.replace(startPos, endPos, replacement);
}
static int getStartPosition(DocTree docTree, VisitorState state) {
DocSourcePositions positions = JavacTrees.instance(state.context).getSourcePositions();
CompilationUnitTree compilationUnitTree = state.getPath().getCompilationUnit();
return (int) positions.getStartPosition(compilationUnitTree, getDocCommentTree(state), docTree);
}
static int getEndPosition(DocTree docTree, VisitorState state) {
DocSourcePositions positions = JavacTrees.instance(state.context).getSourcePositions();
CompilationUnitTree compilationUnitTree = state.getPath().getCompilationUnit();
return (int) positions.getEndPosition(compilationUnitTree, getDocCommentTree(state), docTree);
}
/**
* Gets a {@link DiagnosticPosition} for the {@link DocTree} pointed to by {@code path}, attached
* to the {@link Tree} which it documents.
*/
static DiagnosticPosition diagnosticPosition(DocTreePath path, VisitorState state) {
int startPosition = getStartPosition(path.getLeaf(), state);
Tree tree = path.getTreePath().getLeaf();
if (startPosition == Position.NOPOS) {
// javac doesn't seem to store positions for e.g. trivial empty javadoc like `/** */`
// see: https://github.com/google/error-prone/issues/1981
startPosition = ASTHelpers.getStartPosition(tree);
}
return getDiagnosticPosition(startPosition, tree);
}
static DiagnosticPosition getDiagnosticPosition(int startPosition, Tree tree) {
return new FixedPosition(tree, startPosition);
}
@Nullable
static DocTreePath getDocTreePath(VisitorState state) {
DocCommentTree docCommentTree = getDocCommentTree(state);
if (docCommentTree == null) {
return null;
}
return new DocTreePath(state.getPath(), docCommentTree);
}
@Nullable
private static DocCommentTree getDocCommentTree(VisitorState state) {
return JavacTrees.instance(state.context).getDocCommentTree(state.getPath());
}
private Utils() {}
}