org.jetbrains.jet.lang.cfg.UnreachableCode.kt Maven / Gradle / Ivy
/*
* Copyright 2010-2014 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 org.jetbrains.jet.lang.cfg
import org.jetbrains.jet.lang.psi.JetElement
import com.intellij.openapi.util.TextRange
import java.util.HashSet
import org.jetbrains.jet.lang.psi.JetPsiUtil
import com.intellij.psi.PsiElement
import com.intellij.psi.PsiElementVisitor
import com.intellij.psi.PsiWhiteSpace
import java.util.ArrayList
import org.jetbrains.jet.lexer.JetTokens
import com.intellij.psi.util.PsiTreeUtil
import com.intellij.psi.PsiComment
trait UnreachableCode {
val elements: Set
fun getUnreachableTextRanges(element: JetElement): List
}
class UnreachableCodeImpl(
private val reachableElements: Set,
private val unreachableElements: Set
) : UnreachableCode {
// This is needed in order to highlight only '1 < 2' and not '1', '<' and '2' as well
override val elements = JetPsiUtil.findRootExpressions(unreachableElements)
override fun getUnreachableTextRanges(element: JetElement): List {
return if (element.hasChildrenInSet(reachableElements)) {
element.getLeavesOrReachableChildren().removeReachableElementsWithMeaninglessSiblings().mergeAdjacentTextRanges()
}
else {
listOf(element.getTextRange()!!)
}
}
private fun JetElement.hasChildrenInSet(set: Set): Boolean {
return PsiTreeUtil.collectElements(this) { it != this }.any { it in set }
}
private fun JetElement.getLeavesOrReachableChildren(): List {
val children = ArrayList()
acceptChildren(object : PsiElementVisitor() {
override fun visitElement(element: PsiElement) {
val isReachable = element is JetElement && reachableElements.contains(element) && !element.hasChildrenInSet(unreachableElements)
if (isReachable || element.getChildren().size == 0) {
children.add(element)
}
else {
element.acceptChildren(this)
}
}
})
return children
}
fun List.removeReachableElementsWithMeaninglessSiblings(): List {
fun PsiElement.isMeaningless() = this is PsiWhiteSpace
|| this.getNode()?.getElementType() == JetTokens.COMMA
|| this is PsiComment
val childrenToRemove = HashSet()
fun collectSiblingsIfMeaningless(elementIndex: Int, direction: Int) {
val index = elementIndex + direction
if (index !in 0..(size() - 1)) return
val element = this[index]
if (element.isMeaningless()) {
childrenToRemove.add(element)
collectSiblingsIfMeaningless(index, direction)
}
}
for ((index, element) in this.withIndices()) {
if (reachableElements.contains(element)) {
childrenToRemove.add(element)
collectSiblingsIfMeaningless(index, -1)
collectSiblingsIfMeaningless(index, 1)
}
}
return this.filter { it !in childrenToRemove }
}
private fun List.mergeAdjacentTextRanges(): List {
val result = ArrayList()
val lastRange = fold(null: TextRange?) {
currentTextRange, element ->
val elementRange = element.getTextRange()!!
if (currentTextRange == null) {
elementRange
}
else if (currentTextRange.getEndOffset() == elementRange.getStartOffset()) {
currentTextRange.union(elementRange)
}
else {
result.add(currentTextRange)
elementRange
}
}
if (lastRange != null) {
result.add(lastRange)
}
return result
}
}