Add ScalaCheck specs

build.sbt

@@ -107,11 +107,14 @@ lazy val xml = crossProject(JSPlatform, JVMPlatform)
     libraryDependencies += "junit" % "junit" % "4.12" % Test,
     libraryDependencies += "com.novocode" % "junit-interface" % "0.11" % Test,
     libraryDependencies += "org.apache.commons" % "commons-lang3" % "3.9" % Test,
+    libraryDependencies += "org.scalacheck" %% "scalacheck" % "1.14.0" % Test,
     libraryDependencies += ("org.scala-lang" % "scala-compiler" % scalaVersion.value % Test).exclude("org.scala-lang.modules", s"scala-xml_${scalaBinaryVersion.value}")
   )
   .jsSettings(
     // Scala.js cannot run forked tests
-    fork in Test := false
+    fork in Test := false,
+
+    libraryDependencies += "org.scalacheck" %%% "scalacheck" % "1.14.0" % Test
   )
   .jsConfigure(_.enablePlugins(ScalaJSJUnitPlugin))
 

jvm/src/test/scala/scala/xml/NodeSeqSpec.scala

@@ -0,0 +1,161 @@
+/*                     __                                               *\
+**     ________ ___   / /  ___     Scala API                            **
+**    / __/ __// _ | / /  / _ |    (c) 2003-2018, LAMP/EPFL             **
+**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
+** /____/\___/_/ |_/____/_/ | |                                         **
+**                          |/                                          **
+\*                                                                      */
+
+package scala.xml
+
+import org.scalacheck.Prop
+import org.scalacheck.{ Properties => PropertiesFor }
+import org.scalacheck.Prop.AnyOperators
+
+object NodeSeqSpec extends PropertiesFor("NodeSeq")
+    with NodeSeqGen {
+
+  property("theSeq") = {
+    Prop.forAll { n: NodeSeq =>
+      n.theSeq ne null
+    }
+  }
+
+  property("length") = {
+    Prop.forAll { n: NodeSeq =>
+      n.length >= 0
+    }
+  }
+
+  property("\\ \"\".throws[Exception]") = {
+    Prop.forAll { n: NodeSeq =>
+      Prop.throws(classOf[IllegalArgumentException]) {
+        (n \ "")
+      }
+    }
+  }
+
+  property("\\ _.throws[Exception]") = {
+    Prop.forAll { n: NodeSeq =>
+      Prop.iff[NodeSeq](n, {
+        // FIXME: Exception thrown in NodeSeq.\.makeSeq
+        case g @ Group(_) =>
+          Prop.throws(classOf[UnsupportedOperationException]) {
+            (g \ "_")
+          }
+        case _ => {
+          (n \ "_")
+          Prop.passed
+        }
+      })
+    }
+  }
+
+  property("\\ @.throws[Exception]") = {
+    Prop.forAll { n: NodeSeq =>
+      Prop.iff[NodeSeq](n, {
+        case n: NodeSeq =>
+          Prop.throws(classOf[IllegalArgumentException]) {
+            (n \ "@")
+          }
+      })
+    }
+  }
+
+  property("\\") = {
+    Prop.forAll { (n: NodeSeq, s: String) =>
+      Prop.iff[String](s, {
+        // FIXME: Should be IllegalArgumentException, regardless of theSeq.
+        case "" =>
+          Prop.throws(classOf[IllegalArgumentException]) {
+            (n \ s)
+          }
+        case "@" =>
+          Prop.throws(classOf[IllegalArgumentException]) {
+            (n \ s)
+          }
+        case s =>
+          (n \ s)
+          Prop.passed
+      })
+    }
+  }
+
+  property("\\\\ \"\".throws[Exception]") = {
+    Prop.forAll { n: NodeSeq =>
+      Prop.throws(classOf[IllegalArgumentException]) {
+        (n \\ "")
+      }
+    }
+  }
+
+  property("\\\\ @.throws[Exception]") = {
+    Prop.forAll { n: NodeSeq =>
+      Prop.iff[NodeSeq](n, {
+        // FIXME: Should be IllegalArgumentException, regardless of theSeq
+        case n if n.filter(!_.isAtom).length == 0 =>
+          (n \\ "@") ?= NodeSeq.Empty
+        case n =>
+          Prop.throws(classOf[IllegalArgumentException]) {
+            (n \\ "@")
+          }
+      })
+    }
+  }
+
+  property("\\\\") = {
+    Prop.forAll { (n: NodeSeq, s: String) =>
+      Prop.iff[String](s, {
+        case "" | "@" =>
+          Prop.throws(classOf[IllegalArgumentException]) {
+            (n \\ s)
+          }
+        case s =>
+          (n \\ s)
+          Prop.passed
+      })
+    }
+  }
+
+  property("\\@ \"\".throws[Exception]") = {
+    Prop.forAll { n: NodeSeq =>
+      Prop.iff[NodeSeq](n, {
+        case s =>
+          Prop.throws(classOf[IllegalArgumentException]) {
+            (n \@ "")
+          }
+      })
+    }
+  }
+
+  property("\\@ _.throws[Exception]") = {
+    Prop.forAll { n: NodeSeq =>
+      Prop.iff[NodeSeq](n, {
+        // FIXME: Exception thrown in NodeSeq.\.makeSeq
+        case g @ Group(_) =>
+          Prop.throws(classOf[UnsupportedOperationException]) {
+            (g \@ "_")
+          }
+        case _ => {
+          (n \@ "_")
+          Prop.passed
+        }
+      })
+    }
+  }
+
+  property("\\@") = {
+    Prop.forAll { (n: NodeSeq, s: String) =>
+      // FIXME: Should be IllegalArgumentException, regardless of theSeq.
+      Prop.throws(classOf[IllegalArgumentException]) {
+        (n \@ s)
+      } || Prop.passed // FIXME: Error conditions are too complex.
+    }
+  }
+
+  property("text") = {
+    Prop.forAll { n: NodeSeq =>
+      n.text.length >= 0
+    }
+  }
+}

jvm/src/test/scala/scala/xml/NodeSerializationSpec.scala

@@ -0,0 +1,27 @@
+/*                     __                                               *\
+**     ________ ___   / /  ___     Scala API                            **
+**    / __/ __// _ | / /  / _ |    (c) 2003-2018, LAMP/EPFL             **
+**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
+** /____/\___/_/ |_/____/_/ | |                                         **
+**                          |/                                          **
+\*                                                                      */
+
+package scala.xml
+
+import org.scalacheck.Prop
+import org.scalacheck.{ Properties => CheckProperties }
+import org.scalacheck.Prop.AnyOperators
+import org.scalacheck.Prop.BooleanOperators
+
+object NodeSerializationSpec extends CheckProperties("NodeSerialization")
+    with NodeGen {
+
+  property("serialization") = {
+    Prop.forAll { n: Node =>
+      Prop.iff[Node](n, {
+        case n =>
+          JavaByteSerialization.roundTrip(n) ?= n
+      })
+    }
+  }
+}

jvm/src/test/scala/scala/xml/XmlStringGen.scala

@@ -0,0 +1,30 @@
+/*                     __                                               *\
+**     ________ ___   / /  ___     Scala API                            **
+**    / __/ __// _ | / /  / _ |    (c) 2003-2018, LAMP/EPFL             **
+**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
+** /____/\___/_/ |_/____/_/ | |                                         **
+**                          |/                                          **
+\*                                                                      */
+
+package scala.xml
+
+import org.scalacheck.Arbitrary
+import org.scalacheck.Gen
+
+trait XmlStringGen extends DocumentGen {
+
+  def xmlDeclGen(version: String, encoding: String): Gen[String] =
+    Gen.oneOf(
+      Gen.const(""),
+      Gen.const(s"<?xml version='$version' encoding='$encoding'?>")
+    )
+
+  val genXmlString: Gen[String] = for {
+    document <- Arbitrary.arbitrary[Document]
+    encoding <- Gen.const("UTF-8") // java.nio.charset.StandardCharsets.UTF_8.name
+    xmlDecl <- xmlDeclGen("1.0", encoding)
+  } yield {
+    val str = xmlDecl + Group(document.children ++ Seq(document.docElem)).toString
+    str
+  }
+}

jvm/src/test/scala/scala/xml/dtd/ExternalIDSpec.scala

@@ -0,0 +1,73 @@
+/*                     __                                               *\
+**     ________ ___   / /  ___     Scala API                            **
+**    / __/ __// _ | / /  / _ |    (c) 2003-2018, LAMP/EPFL             **
+**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
+** /____/\___/_/ |_/____/_/ | |                                         **
+**                          |/                                          **
+\*                                                                      */
+
+package scala.xml
+package dtd
+
+import org.scalacheck.Prop
+import org.scalacheck.{ Properties => PropertiesFor }
+import org.scalacheck.Prop.AnyOperators
+
+object ExternalIDSpec extends PropertiesFor("dtd.ExternalID")
+    with ExternalIDGen {
+
+  property("PublicID.throws[Exception]") = {
+    Prop.forAll(genNonPubIdStr) { s: String =>
+      Prop.throws(classOf[IllegalArgumentException]) {
+        PublicID(s, s)
+      }
+    }
+  }
+
+  property("SystemID.throws[Exception]") = {
+    Prop.forAll(genNonSysIdStr) { s: String =>
+      Prop.throws(classOf[IllegalArgumentException]) {
+        SystemID(s)
+      }
+    }
+  }
+
+  property("SystemID(null).throws[Exception]") = {
+    Prop.throws(classOf[NullPointerException]) {
+      SystemID(null)
+    }
+  }
+
+  property("label") = {
+    Prop.forAll { p: PublicID =>
+      p.label ?= "#PI"
+    }
+  }
+
+  property("attribute") = {
+    Prop.forAll { p: PublicID =>
+      p.attribute ?= Node.NoAttributes
+    }
+  }
+
+  property("child") = {
+    Prop.forAll { p: PublicID =>
+      p.child ?= Nil
+    }
+  }
+
+  property("toString") = Prop.forAll { e: ExternalID =>
+    val str = e.toString
+    Prop.atLeastOne(
+      str ?= "",
+      str ?= s"""SYSTEM '${e.systemId}'""",
+      str ?= s"""SYSTEM "${e.systemId}"""",
+      str ?= s"""PUBLIC '${e.publicId}'""",
+      str ?= s"""PUBLIC "${e.publicId}"""",
+      str ?= s"""PUBLIC '${e.publicId}' '${e.systemId}'""",
+      str ?= s"""PUBLIC "${e.publicId}" "${e.systemId}"""",
+      str ?= s"""PUBLIC '${e.publicId}' "${e.systemId}"""",
+      str ?= s"""PUBLIC "${e.publicId}" '${e.systemId}'"""
+    )
+  }
+}