Track Boolean values which are constant

dataunitylab · Nov 9, 2023 · 4cac5e8 · 4cac5e8
1 parent d79ae98
commit 4cac5e8
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Showing 4 changed files with 105 additions and 5 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -15,6 +15,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Set `items` to `false` in tuple schemas
 - Declare lack of support for `unevaluatedItems` and `if`/`then`
 - Declare partial support for `additionalProperties`
+- Track Boolean values which are constant
 
 ## [0.17.0]
 ### Added

diff --git a/src/main/scala/edu/rit/cs/dataunitylab/jsonoid/discovery/schemas/BooleanSchema.scala b/src/main/scala/edu/rit/cs/dataunitylab/jsonoid/discovery/schemas/BooleanSchema.scala
@@ -15,14 +15,23 @@ object BooleanSchema {
     )
   }
 
-  lazy val MinProperties: SchemaProperties[Boolean] =
-    SchemaProperties.empty[Boolean]
+  lazy val MinProperties: SchemaProperties[Boolean] = {
+    val props = SchemaProperties.empty[Boolean]
+    props.add(BooleanConstantProperty())
 
-  lazy val SimpleProperties: SchemaProperties[Boolean] =
-    SchemaProperties.empty[Boolean]
+    props
+  }
+
+  lazy val SimpleProperties: SchemaProperties[Boolean] = {
+    val props = SchemaProperties.empty[Boolean]
+    props.add(BooleanConstantProperty())
+
+    props
+  }
 
   lazy val AllProperties: SchemaProperties[Boolean] = {
     val props = SchemaProperties.empty[Boolean]
+    props.add(BooleanConstantProperty())
     props.add(BooleanPercentProperty())
 
     props
@@ -54,6 +63,16 @@ final case class BooleanSchema(
     newSchema
   }
 
+  override def toJson()(implicit p: JsonoidParams): JObject = {
+    properties.getOrNone[BooleanConstantProperty] match {
+      case Some(BooleanConstantProperty(Some(true), _)) =>
+        ("const" -> JBool(true))
+      case Some(BooleanConstantProperty(_, Some(true))) =>
+        ("const" -> JBool(false))
+      case _ => super.toJson()(p)
+    }
+  }
+
   override def collectAnomalies[S <: JValue](
       value: S,
       path: String
@@ -108,3 +127,72 @@ final case class BooleanPercentProperty(
     )
   }
 }
+
+/** Tracks whether all values are either true or false
+  *
+  * @constructor Create a new Boolean constant property
+  * @param allTrue whether all values are true
+  * @param allFalse whether all values are false
+  */
+final case class BooleanConstantProperty(
+    allTrue: Option[Boolean] = None,
+    allFalse: Option[Boolean] = None
+) extends SchemaProperty[Boolean] {
+  override type S = BooleanConstantProperty
+
+  override def newDefault()(implicit
+      p: JsonoidParams
+  ): BooleanConstantProperty =
+    BooleanConstantProperty()
+
+  override val isInformational = false
+
+  override def toJson()(implicit p: JsonoidParams): JObject = Nil
+
+  override def unionMerge(
+      otherProp: BooleanConstantProperty
+  )(implicit p: JsonoidParams): BooleanConstantProperty = {
+    BooleanConstantProperty(
+      (allTrue, otherProp.allTrue) match {
+        case (None, None) => None
+        case _ =>
+          Some(allTrue.getOrElse(false) && otherProp.allTrue.getOrElse(false))
+      },
+      (allFalse, otherProp.allFalse) match {
+        case (None, None) => None
+        case _ =>
+          Some(allFalse.getOrElse(false) && otherProp.allFalse.getOrElse(false))
+      }
+    )
+  }
+
+  override def mergeValue(
+      value: Boolean
+  )(implicit p: JsonoidParams): BooleanConstantProperty = {
+    BooleanConstantProperty(
+      Some(allTrue.getOrElse(true) && value),
+      Some(allFalse.getOrElse(true) && !value)
+    )
+  }
+
+  override def isSubsetOf(
+      other: BooleanConstantProperty,
+      recursive: Boolean = true
+  )(implicit p: JsonoidParams): Boolean = {
+    val trueCompat = (allTrue, other.allTrue) match {
+      case (Some(a), Some(b)) => a >= b
+      case _                  => true
+    }
+    val falseCompat = (allFalse, other.allFalse) match {
+      case (Some(a), Some(b)) => a >= b
+      case _                  => true
+    }
+    trueCompat && falseCompat
+  }
+
+  override def expandTo(
+      other: Option[BooleanConstantProperty]
+  ): BooleanConstantProperty = {
+    BooleanConstantProperty(Some(false), Some(false))
+  }
+}
diff --git a/src/main/scala/edu/rit/cs/dataunitylab/jsonoid/discovery/schemas/JsonSchema.scala b/src/main/scala/edu/rit/cs/dataunitylab/jsonoid/discovery/schemas/JsonSchema.scala
@@ -67,7 +67,13 @@ object JsonSchema {
           case e: org.json4s.MappingException => Set.empty[JValue]
           // $COVERAGE-ON$
         }
-      EnumSchema(values)
+
+      if (values.size === 1 && values.head.isInstanceOf[JBool]) {
+        // Convert Boolean constants to BooleanSchema
+        BooleanSchema(values.head.asInstanceOf[JBool].value)
+      } else {
+        EnumSchema(values)
+      }
     } else {
       val schemaTypes: List[String] = if ((schema \ "type") =/= JNothing) {
         try {

diff --git a/src/test/scala/edu/rit/cs/dataunitylab/jsonoid/discovery/schemas/BooleanSchemaSpec.scala b/src/test/scala/edu/rit/cs/dataunitylab/jsonoid/discovery/schemas/BooleanSchemaSpec.scala
@@ -43,6 +43,11 @@ class BooleanSchemaSpec extends UnitSpec with ScalaCheckPropertyChecks {
     booleanSchema.validTypes shouldBe Set(classOf[JBool])
   }
 
+  it should "convert to constant where possible" in {
+    val trueSchema = BooleanSchema(true)
+    trueSchema.toJson() shouldBe JObject(List(("const" -> JBool(true))))
+  }
+
   behavior of "BooleanPercentProperty"
 
   it should "track the percentage of true values" in {