Merge pull request #179 from barnardb/matchMap

Select the longest matching key in matchMap
sirthias · Jun 21, 2017 · d7ad77a · d7ad77a
2 parents 2724867 + ecf2ea4
commit d7ad77a
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Showing 2 changed files with 21 additions and 7 deletions.
diff --git a/parboiled-core/src/main/scala/org/parboiled2/Parser.scala b/parboiled-core/src/main/scala/org/parboiled2/Parser.scala
@@ -18,6 +18,7 @@ package org.parboiled2
 
 import scala.annotation.tailrec
 import scala.collection.immutable.VectorBuilder
+import scala.collection.mutable
 import scala.util.{ Failure, Success, Try }
 import scala.util.control.{ NonFatal, NoStackTrace }
 import shapeless._
@@ -449,10 +450,11 @@ abstract class Parser(initialValueStackSize: Int = 16,
    * THIS IS NOT PUBLIC API and might become hidden in future. Use only if you know what you are doing!
    */
   def __matchMap(m: Map[String, Any]): Boolean = {
-    val keys = m.keysIterator
-    while (keys.hasNext) {
+    val prioritizedKeys = new mutable.PriorityQueue[String]()(Ordering.by(_.length))
+    prioritizedKeys ++= m.keysIterator
+    while (prioritizedKeys.nonEmpty) {
       val mark = __saveState
-      val key = keys.next()
+      val key = prioritizedKeys.dequeue()
       if (__matchString(key)) {
         __push(m(key))
         return true
@@ -465,12 +467,13 @@ abstract class Parser(initialValueStackSize: Int = 16,
    * THIS IS NOT PUBLIC API and might become hidden in future. Use only if you know what you are doing!
    */
   def __matchMapWrapped(m: Map[String, Any]): Boolean = {
-    val keys = m.keysIterator
+    val prioritizedKeys = new mutable.PriorityQueue[String]()(Ordering.by(_.length))
+    prioritizedKeys ++= m.keysIterator
     val start = _cursor
     try {
-      while (keys.hasNext) {
+      while (prioritizedKeys.nonEmpty) {
         val mark = __saveState
-        val key = keys.next()
+        val key = prioritizedKeys.dequeue()
         if (__matchStringWrapped(key)) {
           __push(m(key))
           return true
@@ -670,4 +673,4 @@ object ParserMacros {
 
     reify { ctx.Expr[RuleX](ruleTree).splice.asInstanceOf[Rule[I, O]] }
   }
-}
+}
diff --git a/parboiled-core/src/test/scala/org/parboiled2/BasicSpec.scala b/parboiled-core/src/test/scala/org/parboiled2/BasicSpec.scala
@@ -168,6 +168,17 @@ class BasicSpec extends TestParserSpec {
       "blue" must beMatchedWith(3)
       "black" must beMismatched
     }
+
+    "Map[String, T] with keys that prefix each other" in new TestParser1[Int] {
+      val map = Map("a" -> 1, "ab" -> 2, "abc" -> 3, "abcd" -> 4, "abcde" -> 5, "abcdef" -> 6)
+      def targetRule = rule { map ~ EOI }
+      "a" must beMatchedWith(1)
+      "ab" must beMatchedWith(2)
+      "abc" must beMatchedWith(3)
+      "abcd" must beMatchedWith(4)
+      "abcde" must beMatchedWith(5)
+      "abcdef" must beMatchedWith(6)
+    }
   }
 
   "The Parser" should {