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TreeOps.scala
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TreeOps.scala
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package org.scalafmt.util
import scala.annotation.tailrec
import scala.collection.immutable.HashMap
import scala.collection.mutable
import scala.meta._
import scala.meta.classifiers.Classifier
import scala.meta.tokens.Token
import scala.meta.tokens.Token._
import scala.meta.tokens.Tokens
import scala.reflect.ClassTag
import org.scalafmt.Error
import org.scalafmt.config.{DanglingParentheses, ScalafmtConfig}
import org.scalafmt.internal.{Modification, Space}
import org.scalafmt.internal.{FormatToken, FormatTokens}
import org.scalafmt.util.InfixApp._
/** Stateless helper functions on `scala.meta.Tree`.
*/
object TreeOps {
import TokenOps._
@tailrec
def topTypeWith(typeWith: Type.With): Type.With =
typeWith.parent match {
case Some(t: Type.With) => topTypeWith(t)
case _ => typeWith
}
@tailrec
def withChain(top: Tree, res: Seq[Type.With] = Seq.empty): Seq[Type.With] =
top match {
case t: Type.With => withChain(t.lhs, t +: res)
case _ => res
}
def getEnumStatements(enums: Seq[Enumerator]): Seq[Enumerator] = {
val ret = Seq.newBuilder[Enumerator]
enums.zipWithIndex.foreach {
case (x, 0) => x
case (enum: Enumerator.Guard, i) =>
// Only guard that follows another guards starts a statement.
if (enums(i - 1).is[Enumerator.Guard]) {
ret += enum
}
case (x, _) => ret += x
}
ret.result()
}
object SingleArgInBraces {
def unapply(tree: Tree): Option[Term] = tree match {
case t: Term.ArgClause => unapply(t)
case _ => None
}
def unapply(tree: Term.ArgClause): Option[Term] = tree.values match {
case arg :: Nil if inBraces(tree) => Some(arg)
case _ => None
}
@inline def inBraces(tree: Term.ArgClause): Boolean =
tree.tokens.head.is[LeftBrace]
def orBlock(tree: Tree): Option[Tree] = tree match {
case t: Term.ArgClause => unapply(t)
case Term.Block(arg :: Nil) => Some(arg)
case _ => None
}
object OrBlock {
def unapply(tree: Tree): Option[Tree] = orBlock(tree)
}
}
@tailrec
def isBlockFunction(fun: Term.FunctionTerm): Boolean =
fun.parent match {
case Some(p: Term.FunctionTerm) => isBlockFunction(p)
case Some(p) => isExprWithParentInBraces(fun)(p)
case None => false
}
def isFunctionWithBraces(fun: Term.FunctionTerm): Boolean =
fun.parent.exists(isExprWithParentInBraces(fun))
def isExprWithParentInBraces(expr: Tree)(parent: Tree): Boolean =
SingleArgInBraces.orBlock(parent).contains(expr)
def extractStatementsIfAny(tree: Tree): Seq[Tree] =
tree match {
case b: Term.Block => b.stats
case SingleArgInBraces(fun: Term.FunctionTerm) => fun :: Nil
case b: Term.FunctionTerm if isBlockFunction(b) => b.body :: Nil
case t: Pkg => t.stats
// TODO(olafur) would be nice to have an abstract "For" superclass.
case t: Term.For => getEnumStatements(t.enums)
case t: Term.ForYield => getEnumStatements(t.enums)
case t: Term.Match => t.cases
case t: Type.Match => t.cases
case t: Term.PartialFunction => t.cases
case t: Term.Try => t.catchp
case t: Type.Refine => t.stats
case t: Source => t.stats
case t: Template => t.stats
case t: CaseTree if t.body.tokens.nonEmpty => t.body :: Nil
case _ => Nil
}
def getStatementStarts(
tree: Tree,
ftoks: FormatTokens,
soft: SoftKeywordClasses
): Map[TokenHash, Tree] = {
val ret = Map.newBuilder[TokenHash, Tree]
ret.sizeHint(tree.tokens.length)
def addFT(ft: FormatToken, tree: Tree): Unit = ret += hash(ft.left) -> tree
def addTok(token: Token, tree: Tree) = addFT(ftoks.after(token), tree)
def addTree(t: Tree, o: Tree) = ftoks.getHeadOpt(t).foreach(addFT(_, o))
def addOne(t: Tree) = addTree(t, t)
def addAll(trees: Seq[Tree]) = trees.foreach(addOne)
def addDefnTokens(
mods: Seq[Mod],
tree: Tree,
what: String,
isMatch: Token => Boolean
): Unit = {
// Each @annotation gets a separate line
val annotations = mods.filter(_.is[Mod.Annot])
addAll(annotations)
mods.find(!_.is[Mod.Annot]) match {
// Non-annotation modifier, for example `sealed`/`abstract`
case Some(x) => addTree(x, tree)
case _ =>
// No non-annotation modifier exists, fallback to keyword like `object`
tree.tokens.find(isMatch) match {
case Some(x) => addTok(x, tree)
case None => throw Error.CantFindDefnToken(what, tree)
}
}
}
def addDefn[T](mods: Seq[Mod], tree: Tree)(implicit
tag: ClassTag[T]
): Unit = {
val runtimeClass = tag.runtimeClass
addDefnTokens(
mods,
tree,
runtimeClass.getSimpleName,
runtimeClass.isInstance
)
}
def loop(subtree: Tree): Unit = {
subtree match {
case t: Defn.Class => addDefn[KwClass](t.mods, t)
case t: Decl.Def => addDefn[KwDef](t.mods, t)
case t: Defn.Def => addDefn[KwDef](t.mods, t)
case t: Defn.Macro => addDefn[KwDef](t.mods, t)
case t: Decl.Given => addDefn[KwGiven](t.mods, t)
case t: Defn.Given => addDefn[KwGiven](t.mods, t)
case t: Defn.GivenAlias => addDefn[KwGiven](t.mods, t)
case t: Defn.Enum => addDefn[KwEnum](t.mods, t)
case t: Defn.ExtensionGroup =>
addDefnTokens(Nil, t, "extension", soft.KwExtension.unapply)
case t: Defn.Object => addDefn[KwObject](t.mods, t)
case t: Defn.Trait => addDefn[KwTrait](t.mods, t)
case t: Defn.Type => addDefn[KwType](t.mods, t)
case t: Decl.Type => addDefn[KwType](t.mods, t)
case t: Defn.Val => addDefn[KwVal](t.mods, t)
case t: Decl.Val => addDefn[KwVal](t.mods, t)
case t: Defn.Var => addDefn[KwVar](t.mods, t)
case t: Decl.Var => addDefn[KwVar](t.mods, t)
case t: Ctor.Secondary =>
addDefn[KwDef](t.mods, t)
addAll(t.stats)
// special handling for rewritten blocks
case t @ Term.Block(arg :: Nil) // single-stat block
if t.tokens.headOption // see if opening brace was removed
.exists(x => x.is[Token.LeftBrace] && ftoks(x).left.ne(x)) =>
if (arg.is[Term.FunctionTerm]) {
// handle rewritten apply { { x => b } } to a { x => b }
val parentApply = findTreeWithParent(t) {
case Term.Block(_) => None
case p @ Term.ArgClause(_ :: Nil, _) => Some(isParentAnApply(p))
case _ => Some(false)
}
if (parentApply.isDefined) addOne(arg)
}
// special handling for rewritten apply(x => { b }) to a { x => b }
case t: Term.Apply =>
val ac = t.argClause
ac.values match {
case (f: Term.FunctionTerm) :: Nil if ac.tokens.lastOption.exists {
x => // see if closing paren is now brace
x.is[Token.RightParen] &&
ftoks.prevNonComment(ftoks(x)).left.is[Token.RightBrace]
} =>
addOne(f)
case _ =>
}
case t => // Nothing
addAll(extractStatementsIfAny(t))
}
subtree.children.foreach(loop)
}
loop(tree)
ret.result()
}
/** Finds matching parens [({})].
*
* Contains lookup keys in both directions, opening [({ and closing })].
*/
def getMatchingParentheses(tokens: Iterable[Token]): Map[TokenHash, Token] = {
val ret = Map.newBuilder[TokenHash, Token]
var stack = List.empty[Token]
tokens.foreach {
case open @ (LeftBrace() | LeftBracket() | LeftParen() |
Interpolation.Start() | Xml.Start() | Xml.SpliceStart()) =>
stack = open :: stack
case close @ (RightBrace() | RightBracket() | RightParen() |
Interpolation.End() | Xml.End() | Xml.SpliceEnd()) =>
val open = stack.head
assertValidParens(open, close)
ret += hash(open) -> close
ret += hash(close) -> open
stack = stack.tail
case _ =>
}
if (stack.nonEmpty)
throw new IllegalArgumentException(
stack.map(x => s"[${x.end}]$x").mkString("Orphan parens (", ", ", ")")
)
val result = ret.result()
result
}
def assertValidParens(open: Token, close: Token): Unit = {
(open, close) match {
case (Interpolation.Start(), Interpolation.End()) =>
case (Xml.Start(), Xml.End()) =>
case (Xml.SpliceStart(), Xml.SpliceEnd()) =>
case (LeftBrace(), RightBrace()) =>
case (LeftBracket(), RightBracket()) =>
case (LeftParen(), RightParen()) =>
case (o, c) =>
throw new IllegalArgumentException(s"Mismatching parens ($o, $c)")
}
}
final def childOf(child: Tree, tree: Tree): Boolean =
findTreeOrParentSimple(child)(_ eq tree).isDefined
@tailrec
final def numParents(tree: Tree, cnt: Int = 0)(f: Tree => Boolean): Int =
tree.parent match {
case Some(p) => numParents(p, if (f(p)) 1 + cnt else cnt)(f)
case _ => cnt
}
/** Returns first ancestor which matches the given predicate.
*/
def findTreeOrParent(
tree: Tree
)(pred: Tree => Option[Boolean]): Option[Tree] =
findTreeEx(tree) { t =>
pred(t) match {
case None => t.parent
case Some(true) => Some(null)
case Some(false) => None
}
}
/** Returns first tree which matches the given predicate. The predicate
* returns None to indicate failure; or the tree to recurse to; if the tree
* is null (or the same as current tree), the current tree is returned.
*/
@tailrec
def findTreeEx(
tree: Tree
)(pred: Tree => Option[Tree]): Option[Tree] =
pred(tree) match {
case None => None
case Some(null | `tree`) => Some(tree)
case Some(r) => findTreeEx(r)(pred)
}
def findTreeOrParentSimple(
tree: Tree,
flag: Boolean = true
)(pred: Tree => Boolean): Option[Tree] =
findTreeOrParent(tree)(x => if (pred(x) == flag) Some(true) else None)
/** Returns first ancestor whose parent matches the given predicate. The
* predicate returns None to continue with the parent, or the boolean match
* flag, which terminates the search.
*/
def findTreeWithParent(
tree: Tree
)(pred: Tree => Option[Boolean]): Option[Tree] =
findTreeWithParentEx(tree) { t =>
pred(t) match {
case None => Some(t)
case Some(true) => Some(null)
case Some(false) => None
}
}
/** Returns first ancestor whose parent matches the given predicate. The
* predicate returns None to indicate failure; or the tree to recurse to; if
* the recurse-to tree is null, the current tree is returned.
*/
@tailrec
def findTreeWithParentEx(
tree: Tree
)(pred: Tree => Option[Tree]): Option[Tree] =
tree.parent match {
case None => None
case Some(p) =>
pred(p) match {
case None => None
case Some(null) => Some(tree)
case Some(r) => findTreeWithParentEx(r)(pred)
}
}
def findTreeWithParentSimple(
tree: Tree,
flag: Boolean = true
)(pred: Tree => Boolean): Option[Tree] =
findTreeWithParent(tree)(x => if (pred(x) == flag) Some(true) else None)
/** Returns first ancestor with a parent of a given type.
*/
def findTreeWithParentOfType[A <: Tree](tree: Tree)(implicit
classifier: Classifier[Tree, A]
): Option[Tree] =
findTreeWithParentSimple(tree)(classifier.apply)
/** Returns true if a matching ancestor of a given type exists.
*/
@inline
def existsParentOfType[A <: Tree](
tree: Tree
)(implicit classifier: Classifier[Tree, A]): Boolean =
findTreeWithParentOfType[A](tree).isDefined
@tailrec
def defDefBody(tree: Tree): Option[Tree] =
tree match {
case d: Defn with Tree.WithBody => Some(d.body)
case d: Defn with Stat.WithTemplate => Some(d.templ)
case t: Ctor.Secondary => Some(t.init)
case _: Ctor.Primary | _: Pat.Var | _: Term.Name =>
tree.parent match {
case Some(p) => defDefBody(p)
case _ => None
}
case _ => None
}
@tailrec
def defDefBodyParent(tree: Tree): Option[Tree] = tree.parent match {
case Some(p: Member.ParamClauseGroup) => defDefBodyParent(p)
case Some(p) => defDefBody(p)
case None => None
}
@tailrec
private def defDefReturnTypeImpl(tree: Tree): Option[Type] =
tree match {
case d: Decl.Def => Some(d.decltpe)
case d: Defn.Def => d.decltpe
case d: Defn.Macro => d.decltpe
case d: Defn.Given => d.templ.inits.headOption.map(_.tpe)
case d: Defn.GivenAlias => Some(d.decltpe)
case d: Decl.Given => Some(d.decltpe)
case d: Defn.Val => d.decltpe
case d: Defn.Var => d.decltpe
case _: Pat.Var | _: Term.Name | _: Member.ParamClause |
_: Member.ParamClauseGroup =>
tree.parent match {
case Some(p) => defDefReturnTypeImpl(p)
case _ => None
}
case _ => None
}
def defDefReturnType(tree: Tree): Option[Type] =
defDefReturnTypeImpl(tree).filter(!_.pos.isEmpty)
val DefDefReturnTypeLeft =
new FormatToken.ExtractFromMeta(x => defDefReturnType(x.leftOwner))
val DefDefReturnTypeRight =
new FormatToken.ExtractFromMeta(x => defDefReturnType(x.rightOwner))
def isParamClauseSite(tree: Tree): Boolean =
tree match {
case _: Type.ParamClause => !tree.parent.exists(_.is[Type.Lambda])
case _: Term.ParamClause =>
tree.parent match {
case Some(p: Term.FunctionTerm) => !isSeqSingle(p.paramClause.values)
case _ => true
}
case _: Type.FuncParamClause | _: Type.Tuple => true
case _: Member.Function => true // enclosed
case _ => false
}
@inline
def isTokenHeadOrBefore(token: Token, owner: Tree): Boolean =
isTokenHeadOrBefore(token, owner.pos)
@inline
def isTokenHeadOrBefore(token: Token, pos: Position): Boolean =
pos.start >= token.start
@inline
def isTokenLastOrAfter(token: Token, owner: Tree): Boolean =
isTokenLastOrAfter(token, owner.pos)
@inline
def isTokenLastOrAfter(token: Token, pos: Position): Boolean =
pos.end <= token.end
def isArgClauseSite(tree: Tree)(implicit style: ScalafmtConfig): Boolean =
tree match {
case t: Member.ArgClause =>
!t.parent.exists(_.is[Member.Infix]) || (t.values match {
case (_: Term.Assign | _: Lit.Unit) :: Nil => true
case Nil | _ :: Nil => false
case _ => style.newlines.formatInfix
})
case _: Term.Super | _: Lit.Unit | _: Term.Tuple | _: Pat.Tuple => true
case _ => false
}
def isTuple(tree: Tree): Boolean =
tree.is[Member.Tuple]
def noSpaceBeforeOpeningParen(
tree: Tree
): Boolean =
tree match {
case _: Term.Super => true
case t: Member.ArgClause => !t.parent.exists(_.is[Member.Infix])
case _: Member.ParamClause =>
tree.parent.exists {
case _: Term.FunctionTerm => false
case t: Ctor.Primary =>
t.mods.isEmpty || !t.paramClauses.headOption.contains(tree)
case _ => true
}
case _ => false
}
def isModPrivateProtected(tree: Tree): Boolean =
tree match {
case _: Mod.Private | _: Mod.Protected => true
case _ => false
}
val DefValAssignLeft =
new FormatToken.ExtractFromMeta(_.leftOwner match {
case _: Enumerator => None // it's WithBody
case t: Ctor.Secondary => Some(t.init)
case t: Tree.WithBody => Some(t.body)
case t: Term.Param => t.default
case _ => None
})
/** How many parents of tree are Term.Apply?
*/
@tailrec
def nestedApplies(tree: Tree): Int = tree match {
case _: Member.SyntaxValuesClause | _: Member.ParamClauseGroup =>
tree.parent match {
case Some(p) => nestedApplies(p)
case _ => 0
}
case _ =>
numParents(tree) {
case _: Term.Apply | _: Term.ApplyInfix | _: Type.Apply => true
case _ => false
}
}
def nestedSelect(tree: Tree): Int = numParents(tree)(_.is[Term.Select])
/** Calculates depth to deepest child in tree.
*/
// TODO(olafur) inefficient, precalculate?
def treeDepth(tree: Tree): Int = tree match {
case Member.ParamClauseGroup(tparams, paramss) =>
maxTreeDepth(tparams +: paramss)
case Member.SyntaxValuesClause(v) => maxTreeDepth(v)
case _ =>
val children = tree.children
if (children.isEmpty) 0 else 1 + maxTreeDepth(children)
}
def maxTreeDepth(trees: Seq[Tree]): Int =
trees.foldLeft(0) { case (res, t) => math.max(res, treeDepth(t)) }
@tailrec
final def lastLambda(first: Term.FunctionTerm): Term.FunctionTerm =
first.body match {
case child: Term.FunctionTerm => lastLambda(child)
case _ => first
}
@inline final def isInfixOp(tree: Tree): Boolean =
AsInfixOp.unapply(tree).isDefined
object AsInfixOp {
def unapply(tree: Tree): Option[Member.Infix] =
tree.parent.collect {
case ia: Member.Infix if ia.op eq tree => ia
}
}
@inline
final def asInfixApp(tree: Tree): Option[Member.Infix] =
InfixApp.unapply(tree)
@inline
final def isInfixApp(tree: Tree): Boolean = asInfixApp(tree).isDefined
@tailrec
def findNextInfixInParent(tree: Tree, scope: Tree): Option[Name] =
tree.parent match {
case Some(t: Member.ArgClause) => findNextInfixInParent(t, scope)
case Some(t: Member.Infix) if tree ne scope =>
if (t.lhs eq tree) Some(t.op) else findNextInfixInParent(t, scope)
case _ => None
}
def infixSequenceLength(app: Member.Infix): Int = {
val queue = new mutable.Queue[Member.Infix]()
queue += app
var length = 0
while (queue.nonEmpty) {
val elem = queue.dequeue()
length += 1
queue ++= elem.nestedInfixApps
}
length
}
// procedure syntax has decltpe: Some("")
def isProcedureSyntax(defn: Defn.Def): Boolean =
defn.decltpe.exists(_.tokens.isEmpty)
def isXmlBrace(owner: Tree): Boolean =
owner match {
case _: Term.Xml | _: Pat.Xml => true
case b: Term.Block => b.parent.exists(_.isInstanceOf[Term.Xml])
case _ => false
}
def getAssignAtSingleArgCallSite(args: Seq[Tree]): Option[Term.Assign] =
args match {
case Seq(fun: Term.Assign) => Some(fun)
case _ => None
}
@inline
def isSeqSingle(seq: Seq[_]): Boolean = seq.lengthCompare(1) == 0
@inline
def isSeqMulti(seq: Seq[_]): Boolean = seq.lengthCompare(1) > 0
@inline
def isSingleStatBlock(tree: Term.Block): Boolean = isSeqSingle(tree.stats)
@inline
def isMultiStatBlock(tree: Term.Block): Boolean = isSeqMulti(tree.stats)
def isSingleElement(elements: List[Tree], value: Tree): Boolean =
elements match {
case `value` :: Nil => true
case _ => false
}
def getBlockSingleStat(b: Term.Block): Option[Stat] = b.stats match {
case stat :: Nil => Some(stat)
case _ => None
}
def isTreeMultiStatBlock(tree: Tree): Boolean = tree match {
case t: Term.Block => isMultiStatBlock(t)
case _ => false
}
@tailrec
def isTreeSingleExpr(tree: Tree): Boolean = tree match {
case t: Term.Block =>
t.stats match {
case stat :: Nil => isTreeSingleExpr(stat)
case _ => false
}
case _: Defn => false
case _ => true
}
/* An end marker is really more like a closing brace for formatting purposes
* (but not when rewriting) so we should ignore it when considering whether a
* block contains only a single statement. NB: in FormatWriter, when choosing
* to insert or remove end markers, we avoid such borderline cases.
*/
def getSingleStatExceptEndMarker(s: Seq[Stat]): Option[Stat] =
s.headOption.filter { _ =>
val len2 = s.lengthCompare(2)
len2 < 0 || len2 == 0 && s(1).is[Term.EndMarker]
}
def getSingleStatExceptEndMarker(t: Tree): Option[Tree] = t match {
case Term.Block(s) => getSingleStatExceptEndMarker(s)
case _ => Some(t)
}
def getTreeSingleStat(t: Tree): Option[Tree] =
t match {
case b: Term.Block => getBlockSingleStat(b)
case _ => Some(t)
}
def getTreeLineSpan(b: Tree): Int = getTreeLineSpan(b.pos)
def getTreeLineSpan(pos: Position): Int =
if (pos.isEmpty) 0 else pos.endLine - pos.startLine
def hasSingleTermStat(t: Term.Block): Boolean =
getBlockSingleStat(t).exists(_.is[Term])
def hasSingleTermStatIfBlock(t: Tree): Boolean = t match {
case b: Term.Block => hasSingleTermStat(b)
case _ => true
}
/** In cases like:
* {{{
* class X(
* implicit
* private[this] val i1: Int,
* private[this] var i2: String,
* implicit private[this] var i3: Boolean
* )
* }}}
*
* `val i1`, and `var i2` positions do not include their ``Mod.Implicit``.
* `var i3` has a ``Mod.Implicit`` which is included.
*/
def noExplicitImplicit(m: Mod.Implicit, ownerStart: Int): Boolean = {
val modPos = m.pos
modPos.start < ownerStart || modPos.isEmpty
}
def noExplicitImplicit(ownerStart: Int, orElse: Boolean)(m: Mod): Boolean =
m match {
case m: Mod.Implicit => noExplicitImplicit(m, ownerStart)
case _ => orElse
}
def noExplicitImplicit(param: Term.Param): Boolean = {
val pStart = param.pos.start
param.mods.forall(noExplicitImplicit(pStart, true))
}
def getImplicitParamList(kwOwner: Tree): Option[Member.SyntaxValuesClause] =
kwOwner.parent match {
case Some(v @ Term.ArgClause(_, Some(`kwOwner`))) => Some(v)
case Some(v @ Term.ParamClause(_ :: rest, Some(`kwOwner`)))
if !kwOwner.is[Mod.Implicit] || rest.isEmpty ||
rest.exists(noExplicitImplicit) =>
Some(v)
case _ => None
}
def hasImplicitParamList(kwOwner: Tree): Boolean =
getImplicitParamList(kwOwner).isDefined
def shouldNotDangleAtDefnSite(
tree: Option[Tree],
isVerticalMultiline: Boolean
)(implicit style: ScalafmtConfig): Boolean =
!style.danglingParentheses.defnSite || {
val excludes = style.danglingParentheses.getExclude(isVerticalMultiline)
excludes.nonEmpty && tree
.flatMap {
case _: Ctor.Primary | _: Defn.Class =>
Some(DanglingParentheses.Exclude.`class`)
case _: Defn.Trait => Some(DanglingParentheses.Exclude.`trait`)
case _: Defn.Enum => Some(DanglingParentheses.Exclude.`enum`)
case t: Member.ParamClauseGroup =>
t.parent.collect {
case _: Defn.ExtensionGroup =>
DanglingParentheses.Exclude.`extension`
case _: Decl.Def | _: Defn.Def | _: Defn.Macro =>
DanglingParentheses.Exclude.`def`
case _: Decl.Given | _: Defn.Given | _: Defn.GivenAlias =>
DanglingParentheses.Exclude.`given`
}
case _ => None
}
.exists(excludes.contains)
}
def isChildOfCaseClause(tree: Tree): Boolean =
findTreeWithParent(tree) {
case t: Case => Some(tree ne t.body)
case _: Pat | _: Pat.ArgClause => None
case _ => Some(false)
}.isDefined
object EndOfFirstCall {
def unapply(tree: Tree): Option[Token] =
traverse(tree, None).map(_.tokens.last)
@tailrec
private def traverse(tree: Tree, res: Option[Tree]): Option[Tree] =
tree match {
case t: Term.Select if res.isDefined => traverse(t.qual, Some(t.qual))
case t: Term.ApplyType => traverse(t.fun, Some(t))
case t: Member.Apply => traverse(t.fun, Some(t.fun))
case t: Init => traverse(t.tpe, Some(t.tpe))
case _ => res
}
}
@inline
def getLastCall(tree: Tree): Tree = getLastCall(tree, tree)
@tailrec
private def getLastCall(tree: Tree, lastCall: Tree): Tree = {
// this is to cover types which include one parameter group at a time
val matches = tree match {
case t: Member.Apply if t.fun eq lastCall => true
case _ => tree eq lastCall
}
if (matches)
tree.parent match {
case Some(p) => getLastCall(p, tree)
case _ => tree
}
else lastCall
}
@tailrec
def findInterpolate(tree: Tree): Option[Term.Interpolate] =
tree match {
case ti: Term.Interpolate => Some(ti)
case _ =>
tree.parent match {
case Some(p) => findInterpolate(p)
case _ => None
}
}
def findArgAfter(end: Int, trees: Seq[Tree]): Option[Tree] =
trees.find(_.pos.start >= end)
def getStripMarginCharForInterpolate(tree: Tree): Option[Char] =
findInterpolate(tree).flatMap(getStripMarginChar)
def getStripMarginChar(t: Tree): Option[Char] = {
t.parent match {
case Some(ts: Term.Select) if ts.name.value == "stripMargin" =>
ts.parent match {
case Some(Term.Apply.Initial(_, List(arg: Lit.Char))) =>
Some(arg.value)
case _ => Some('|')
}
case _ => None
}
}
@inline
def isTripleQuote(syntax: String): Boolean = syntax.startsWith("\"\"\"")
@tailrec
def findFirstTreeBetween(tree: Tree, beg: Token, end: Token): Option[Tree] = {
def isWithinRange(x: Tokens): Boolean = {
x.nonEmpty && x.head.start >= beg.start && x.last.end <= end.end
}
def matches(tree: Tree): Boolean = {
val x = tree.tokens
isWithinRange(x) ||
x.nonEmpty && x.head.start <= beg.start && x.last.end >= end.end
}
if (isWithinRange(tree.tokens)) Some(tree)
else
tree.children.find(matches) match {
case Some(c) => findFirstTreeBetween(c, beg, end)
case _ => None
}
}
@inline
def ifWithoutElse(t: Term.If) = t.elsep.is[Lit.Unit]
def ifWithoutElse(tree: Tree): Boolean = tree match {
case t: Term.If => ifWithoutElse(t)
case _ => false
}
@tailrec
def existsIfWithoutElse(t: Term.If): Boolean =
existsIfWithoutElse(t.thenp) || (t.elsep match {
case x: Term.If => existsIfWithoutElse(x)
case _ => ifWithoutElse(t)
})
def existsIfWithoutElse(tree: Tree): Boolean = tree match {
case t: Term.If => existsIfWithoutElse(t)
case _ => false
}
def cannotStartSelectChainOnExpr(expr: Term): Boolean =
expr match {
case _: Term.Placeholder => true
case t: Term.Name => isSymbolicName(t.value)
case t: Term.Select => isSymbolicName(t.name.value)
case _ => false
}
// Redundant {} block around case statements
def isCaseBodyABlock(ft: FormatToken, caseStat: CaseTree): Boolean =
ft.right.is[Token.LeftBrace] && (caseStat.body eq ft.meta.rightOwner)
def getStartOfTemplateBody(template: Template): Option[Token] =
template.self.tokens.headOption
.orElse(template.stats.headOption.flatMap(_.tokens.headOption))
def getTemplateGroups(template: Template): Option[Seq[List[Tree]]] = {
val groups = Seq(template.inits, template.derives).filter(_.nonEmpty)
if (groups.isEmpty) None else Some(groups)
}
@tailrec
final def followedBySelectOrApply(tree: Tree): Boolean = tree.parent match {
case Some(p: Term.New) => followedBySelectOrApply(p)
case Some(_: Term.Select) => true
case Some(p: Member.Infix) => p.lhs.eq(tree) || followedBySelectOrApply(p)
case Some(p: Member.Apply) if p.fun eq tree =>
p.argClause match {
case SingleArgInBraces(_) => false
case _ => true
}
case _ => false
}
// Scala syntax allows commas before right braces in weird places,
// like constructor bodies:
// def this() = {
// this(1),
// }
// This code simply ignores those commas because it does not
// consider them "trailing" commas. It does not remove them
// in the TrailingCommas.never branch, nor does it
// try to add them in the TrainingCommas.always branch.
def rightIsCloseDelimForTrailingComma(
left: Token,
ft: FormatToken,
whenNL: Boolean = true
)(implicit style: ScalafmtConfig): Boolean = {
def owner = ft.meta.rightOwner
def isArgOrParamClauseSite(tree: Tree) =
!whenNL || isArgClauseSite(tree) || isParamClauseSite(tree)
// skip empty parens/braces/brackets
ft.right match {
case _: Token.RightBrace =>
!left.is[Token.LeftBrace] && owner.is[Importer]
case _: Token.RightParen =>
!left.is[Token.LeftParen] && isArgOrParamClauseSite(owner)
case _: Token.RightBracket =>
!left.is[Token.LeftBracket] && isArgOrParamClauseSite(owner)
case _ => false
}
}
def findEnclosedBetweenParens(
lt: Token,
rt: Token,
tree: Tree
): Option[Tree] = {
val beforeParens = lt.start
val afterParens = rt.end
@tailrec
def iter(trees: List[Tree]): Option[Tree] = trees match {
case head :: rest =>
val headPos = head.pos
val headEnd = headPos.end
if (headEnd <= beforeParens) iter(rest)
else if (
headEnd <= afterParens && headPos.start < headEnd &&
rest.headOption.forall(_.pos.start >= afterParens)
) Some(head)
else None
case _ => None
}
val pos = tree.pos
val found = beforeParens <= pos.start && pos.end <= afterParens
if (found) Some(tree) else iter(tree.children)
}
def getStyleAndOwners(
topSourceTree: Tree,
baseStyle: ScalafmtConfig
): (ScalafmtConfig, collection.Map[TokenHash, Tree]) = {
var infixCount = 0
// Creates lookup table from token offset to its closest scala.meta tree
val ownersMap = HashMap.newBuilder[TokenHash, Tree]
@inline def setOwner(tok: Token, tree: Tree): Unit =
ownersMap += hash(tok) -> tree
val allTokens = topSourceTree.tokens
var prevParens: List[Token] = Nil
def treeAt(elemIdx: Int, elem: Tree, outerPrevLPs: Int): Int = {
if (TreeOps.isInfixApp(elem)) infixCount += 1
val endPos = elem.pos.end
val allChildren: List[(Tree, Int)] = elem.children
.flatMap { x =>
val pos = x.pos
val startPos = pos.start
if (startPos == pos.end) None else Some((x, startPos))
}
.sortBy(_._2)
allChildren match {
case Nil =>
@tailrec
def tokenAt(idx: Int): Int =
if (idx == allTokens.length) idx
else {
val tok = allTokens(idx)
if (elem != topSourceTree && tok.start >= endPos) idx
else {
setOwner(tok, elem)
tokenAt(idx + 1)
}
}
tokenAt(elemIdx)
case (firstChild, firstChildStart) :: rest =>
var nextChild = firstChild
var nextChildStart = firstChildStart
var children = rest
var prevChild: Tree = null
var prevLPs = outerPrevLPs
var prevComma: Token = null
@tailrec
def tokenAt(idx: Int): Int = {
if (idx == allTokens.length) idx
else {
val tok = allTokens(idx)
val tokStart = tok.start
if (elem != topSourceTree && tokStart >= endPos) idx
else if (nextChild != null && tokStart >= nextChildStart) {
if (prevChild != null) prevLPs = 0
prevChild = nextChild
val nextIdx = treeAt(idx, nextChild, prevLPs)
children match {
case Nil =>
nextChild = null
nextChildStart = endPos
case (head, start) :: rest =>
nextChild = head
children = rest
nextChildStart = start
}
prevComma = null
tokenAt(nextIdx)
} else {
def excludeRightParen: Boolean = elem match {
case t: Term.If =>
prevLPs == 1 && prevChild == t.cond // `expr` after `mods`
case _: Term.While | _: Term.For | _: Term.ForYield =>
prevLPs == 1 && prevChild == firstChild // `expr` is first
case _: Member.SyntaxValuesClause | _: Member.Tuple |
_: Term.Do | _: Term.AnonymousFunction =>
endPos == tok.end
case t: Init => prevChild ne t.tpe // include tpe
case _: Ctor.Primary => true
case _ => false
}
if (prevParens.nonEmpty && tok.is[RightParen]) {
if (prevChild == null || prevLPs <= 0 || excludeRightParen)
setOwner(tok, elem)
else {
setOwner(tok, prevChild)
setOwner(prevParens.head, prevChild)
if (prevComma != null)
setOwner(prevComma, prevChild)
}
prevLPs -= 1