Add parser tests (#103)

project/WeePicklePlugin.scala

@@ -14,8 +14,8 @@ object WeePicklePlugin extends AutoPlugin {
 
     val scala211 = "2.11.12"
     val scala212 = "2.12.12"
-    val scala213 = "2.13.5"
-    val scala3 = "3.0.1"
+    val scala213 = "2.13.7"
+    val scala3 = "3.1.0"
     val supportedScala2Versions = Seq(scala211, scala212, scala213)
     val supportedScalaVersions = supportedScala2Versions :+ scala3
 
@@ -119,6 +119,14 @@ object WeePicklePlugin extends AutoPlugin {
 
       builder.result()
     },
+    Test / scalacOptions ++= {
+      scalaBinaryVersion.value match {
+        case "3" => Seq(
+          "-Wconf:cat=deprecation:info" // scalacheck uses Stream
+        )
+        case _ => Nil
+      }
+    },
     testFrameworks += new TestFramework("utest.runner.Framework"),
   )
 }

weejson/src/test/scala/com/rallyhealth/weejson/v1/GenBufferedValue.scala

@@ -1,11 +1,11 @@
 package com.rallyhealth.weejson.v1
 
-import org.scalacheck.{Arbitrary, Gen}
+import org.scalacheck.{Arbitrary, Gen, Shrink}
 
 import scala.collection.mutable.ArrayBuffer
 
 trait GenBufferedValue {
-  import BufferedValue.{Arr, Obj, Str, Bool, Null, AnyNum}
+  import com.rallyhealth.weejson.v1.BufferedValue._
 
   def genArray(depth: Int): Gen[Arr] = {
     for {
@@ -52,6 +52,17 @@ trait GenBufferedValue {
   }
 
   implicit val arbNum: Arbitrary[AnyNum] = Arbitrary {
-    Arbitrary.arbitrary[Double].map(BigDecimal(_)).map(AnyNum(_))
+    Arbitrary.arbitrary[Double].map(BigDecimal(_)).map(AnyNum(_)) // TODO open to all BigDecimals after #102
+  }
+
+  implicit val shrinkValue: Shrink[BufferedValue] = Shrink[BufferedValue] {
+    case Obj(map) => Shrink.shrink(map).map(Obj(_))
+    case Arr(buf) => Shrink.shrink(buf).map(Arr(_))
+    case NumDouble(d) => NumLong(d.longValue) +: Shrink.shrink(d).map(NumDouble(_))
+    case NumLong(long) => Shrink.shrink(long).map(NumLong(_))
+    case Str(s) => Shrink.shrink(s).map(Str(_))
+    case Timestamp(s) => Shrink.shrink(s).map(Timestamp(_))
+    case Ext(tag, bytes) => Shrink.shrink(bytes).map(Ext(tag, _))
+    case _ => Stream.empty
   }
 }

weejson/src/test/scala/com/rallyhealth/weejson/v1/GenValue.scala

@@ -1,7 +1,7 @@
 package com.rallyhealth.weejson.v1
 
 import com.rallyhealth.weejson.v1._
-import org.scalacheck.{Arbitrary, Gen}
+import org.scalacheck.{Arbitrary, Gen, Shrink}
 
 import scala.collection.mutable.ArrayBuffer
 
@@ -54,4 +54,12 @@ trait GenValue {
   implicit val arbNum: Arbitrary[Num] = Arbitrary {
     Arbitrary.arbitrary[Double].map(Num(_))
   }
+
+  implicit val shrinkValue: Shrink[Value] = Shrink[Value] {
+    case Obj(map) => Shrink.shrink(map).map(Obj(_))
+    case Arr(buf) => Shrink.shrink(buf).map(Arr(_))
+    case Num(bd) => Shrink.shrink(bd).map(Num(_))
+    case Str(s) => Shrink.shrink(s).map(Str(_))
+    case _ => Stream.empty
+  }
 }

weepickle-tests/src/test/scala/com/rallyhealth/weepickle/v1/MaxDepthVisitor.scala

@@ -0,0 +1,46 @@
+package com.rallyhealth.weepickle.v1
+
+import com.rallyhealth.weepickle.v1.core.{ArrVisitor, NoOpVisitor, ObjArrVisitor, ObjVisitor, Visitor}
+
+/**
+  * Returns the max depth encountered.
+  * Useful for creating valid test inputs that can be sent to a parser that throws at high depth.
+  */
+class MaxDepthVisitor extends NoOpVisitor[Int](0) {
+
+  private[this] var maxDepth = 0
+  private[this] var currentDepth = 0
+
+  private def inc() = {
+    currentDepth += 1
+    maxDepth = math.max(maxDepth, currentDepth)
+  }
+
+  private def dec() = {
+    currentDepth -= 1
+  }
+
+  private trait ObjArrBase {
+    self: ObjArrVisitor[Any, Int] =>
+
+    override def subVisitor: Visitor[_, _] = {
+      inc()
+      MaxDepthVisitor.this.map(_ => maxDepth)
+    }
+
+    override def visitValue(v: Any): Unit = dec()
+
+    override def visitEnd(): Int = maxDepth
+  }
+
+  override def visitObject(length: Int): ObjVisitor[Any, Int] = new ObjVisitor[Any, Int] with ObjArrBase {
+    override def visitKey(): Visitor[_, _] = {
+      inc()
+      NoOpVisitor
+    }
+
+    override def visitKeyValue(v: Any): Unit = dec()
+  }
+
+  override def visitArray(length: Int): ArrVisitor[Any, Int] = new ArrVisitor[Any, Int] with ObjArrBase
+}

weepickle-tests/src/test/scala/com/rallyhealth/weepickle/v1/ParserSpec.scala

@@ -0,0 +1,68 @@
+package com.rallyhealth.weepickle.v1
+
+import com.rallyhealth.weejson.v1.jackson.{FromJson, ToJson, ToPrettyJson}
+import com.rallyhealth.weejson.v1.{BufferedValue, GenBufferedValue}
+import com.rallyhealth.weepickle.v1.core.FromInput
+import org.scalactic.TypeCheckedTripleEquals
+import org.scalatest.freespec.AnyFreeSpec
+import org.scalatestplus.scalacheck.ScalaCheckPropertyChecks
+
+import java.io.{ByteArrayInputStream, StringReader}
+import java.nio.file.Files
+import scala.language.{existentials, implicitConversions}
+
+abstract class ParserSpec(parse: Array[Byte] => FromInput, depthLimit: Int = 100)
+  extends AnyFreeSpec
+    with ScalaCheckPropertyChecks
+    with GenBufferedValue
+    with TypeCheckedTripleEquals {
+
+  import com.rallyhealth.weejson.v1.BufferedValue._
+  import com.rallyhealth.weejson.v1.BufferedValueOps._
+
+  private implicit def toBytes(s: String): Array[Byte] = s.getBytes
+
+  "roundtrip" in testJson()
+  "deep arr" in testDepth(Arr(_))
+  "deep obj" in testDepth(b => Obj("k" -> b))
+
+  private def testJson(tweak: BufferedValue => BufferedValue = identity) = {
+    forAll { (b: BufferedValue) =>
+      val value = tweak(b)
+      val expected = value.transform(ToJson.string)
+
+      def testInput(s: Array[Byte]) = assert(parse(s).transform(ToJson.string) === expected)
+
+      testInput(expected)
+      testInput(s"\n $expected \n ")
+      testInput(value.transform(ToPrettyJson.bytes))
+
+      assert(parse(expected.getBytes()).transform(BufferedValue.Builder) === value)
+    }
+  }
+
+  private def testDepth(f: BufferedValue => BufferedValue) = {
+    testJson { in =>
+      val depth = in.transform(new MaxDepthVisitor)
+      val numPads = math.max(depthLimit - depth, 0)
+      (0 to numPads).foldLeft(in)((p, _) => f(p))
+    }
+  }
+}
+
+class FromJsonBytesSpec extends ParserSpec(FromJson(_))
+
+class FromJsonStringSpec extends ParserSpec(b => FromJson(new String(b)))
+
+class FromJsonInputStreamSpec extends ParserSpec(b => FromJson(new ByteArrayInputStream(b)))
+
+class FromJsonReaderSpec extends ParserSpec(b => FromJson(new StringReader(new String(b))))
+
+class FromJsonPathSpec extends ParserSpec(
+  b => FromJson(Files.write(Files.createTempFile("FromJsonPathSpec", ".json"), b))
+)
+
+class FromJsonFileSpec extends ParserSpec(
+  b => FromJson(Files.write(Files.createTempFile("FromJsonFileSpec", ".json"), b).toFile)
+)
+