Add support for pretty JSON rendering

Author: sirthias

Diff for: core/src/main/scala/io/bullet/borer/Borer.scala

@@ -8,9 +8,9 @@
 
 package io.bullet.borer
 
-import io.bullet.borer.cbor._
+import io.bullet.borer.cbor.*
 import io.bullet.borer.internal.Util
-import io.bullet.borer.json._
+import io.bullet.borer.json.*
 
 import scala.annotation.unchecked.uncheckedVariance
 
@@ -52,7 +52,7 @@ case object Cbor extends Target:
       output: Output,
       config: EncodingConfig = EncodingConfig.default,
       receiverWrapper: Receiver.Transformer[EncodingConfig] = CborValidation.wrapper): Writer =
-    new Writer(output, receiverWrapper(CborRenderer(output), config), this, config)
+    new Writer(output, receiverWrapper(CborRenderer(output, config), config), this, config)
 
   /**
    * Constructs a new [[Reader]] that reads CBOR from the given [[Input]].
@@ -211,7 +211,7 @@ case object Json extends Target:
       output: Output,
       config: EncodingConfig = EncodingConfig.default,
       receiverWrapper: Receiver.Transformer[EncodingConfig] = Receiver.nopTransformer): Writer =
-    new Writer(output, receiverWrapper(JsonRenderer(output), config), null, config)
+    new Writer(output, receiverWrapper(JsonRenderer(output, config), config), null, config)
 
   /**
    * Constructs a new [[Reader]] that reads JSON from the given [[Input]].
@@ -227,12 +227,14 @@ case object Json extends Target:
 
   final case class EncodingConfig(
       bufferSize: Int = 1024,
-      allowBufferCaching: Boolean = true
+      allowBufferCaching: Boolean = true,
+      indent: Int = 0
   ) extends Borer.EncodingConfig:
 
     def compressFloatingPointValues = false
 
     if (bufferSize < 8) throw new IllegalArgumentException(s"bufferSize must be >= 8, but was $bufferSize")
+    if (indent < 0) throw new IllegalArgumentException(s"indent must be non-negative, but was $indent")
 
   object EncodingConfig:
     val default = EncodingConfig()

Diff for: core/src/main/scala/io/bullet/borer/EncodingSetup.scala

@@ -8,11 +8,10 @@
 
 package io.bullet.borer
 
-import java.nio.charset.StandardCharsets.UTF_8
-import java.nio.ByteBuffer
-
 import io.bullet.borer.internal.Renderer
 
+import java.nio.charset.StandardCharsets.UTF_8
+import java.nio.ByteBuffer
 import scala.util.{Failure, Success, Try}
 import scala.util.control.NonFatal
 
@@ -80,6 +79,8 @@ object EncodingSetup:
 
   sealed trait JsonApi[T, Config <: Borer.EncodingConfig] extends Api[Config]:
 
+    def withPrettyRendering(indent: Int = 2): this.type
+
     /**
      * Short-cut for encoding to a plain byte array, throwing an exception in case of any failures,
      * and then immediately UTF-8 decoding into a [[String]].
@@ -91,11 +92,14 @@ object EncodingSetup:
       target: Target,
       defaultConfig: Config,
       defaultWrapper: Receiver.Transformer[Config],
-      rendererCreator: Output => Renderer)
+      rendererCreator: (Output, Config) => Renderer)
       extends CommonApi.Impl[Config](defaultConfig, defaultWrapper) with JsonApi[T, Config] with Sealed[Output, Any]:
 
     private[this] var _output: Output = _
 
+    def withPrettyRendering(indent: Int): Impl.this.type =
+      withConfig(config.asInstanceOf[Json.EncodingConfig].copy(indent = indent).asInstanceOf[Config])
+
     def toUtf8String: String = new String(toByteArray, UTF_8)
 
     def toByteArray: Array[Byte] = to[Array[Byte]].result
@@ -119,37 +123,37 @@ object EncodingSetup:
       this.asInstanceOf[Sealed[op.Out, R]]
 
     def result: Any =
-      val renderer = rendererCreator(_output)
+      val renderer = rendererCreator(_output, config)
       try render(renderer).out.result()
       catch
         case e: Borer.Error[_] => throw e.withOut(renderer.out)
         case NonFatal(e)       => throw new Borer.Error.General(renderer.out, e)
 
     def resultTry: Try[Any] =
-      val renderer = rendererCreator(_output)
+      val renderer = rendererCreator(_output, config)
       try Success(render(renderer).out.result())
       catch
         case e: Borer.Error[_] => Failure(e.withOut(renderer.out))
         case NonFatal(e)       => Failure(new Borer.Error.General(renderer.out, e))
 
     def resultEither: Either[Borer.Error[Output], Any] =
-      val renderer = rendererCreator(_output)
+      val renderer = rendererCreator(_output, config)
       try Right(render(renderer).out.result())
       catch
         case e: Borer.Error[_] => Left(e.withOut(renderer.out))
         case NonFatal(e)       => Left(new Borer.Error.General(renderer.out, e))
 
-    def output: Output = render(rendererCreator(_output)).out
+    def output: Output = render(rendererCreator(_output, config)).out
 
     def outputTry: Try[Output] =
-      val renderer = rendererCreator(_output)
+      val renderer = rendererCreator(_output, config)
       try Success(render(renderer).out)
       catch
         case e: Borer.Error[_] => Failure(e.withOut(renderer.out))
         case NonFatal(e)       => Failure(new Borer.Error.General(renderer.out, e))
 
     def outputEither: Either[Borer.Error[Output], Output] =
-      val renderer = rendererCreator(_output)
+      val renderer = rendererCreator(_output, config)
       try Right(render(renderer).out)
       catch
         case e: Borer.Error[_] => Left(e.withOut(renderer.out))

Diff for: core/src/main/scala/io/bullet/borer/Output.scala

@@ -8,7 +8,7 @@
 
 package io.bullet.borer
 
-import io.bullet.borer.output.{ToByteArrayOutput, ToByteBufferOutput, ToFileOutput, ToOutputStreamOutput, ToUnitOutput}
+import io.bullet.borer.output.*
 
 import scala.annotation.tailrec
 

Diff for: core/src/main/scala/io/bullet/borer/cbor/CborRenderer.scala

@@ -8,11 +8,11 @@
 
 package io.bullet.borer.cbor
 
-import java.nio.charset.StandardCharsets.UTF_8
-
-import io.bullet.borer._
+import io.bullet.borer.*
 import io.bullet.borer.internal.{Renderer, Util}
 
+import java.nio.charset.StandardCharsets.UTF_8
+
 /**
  * Encapsulates basic CBOR encoding logic.
  * Has no internal state and can therefore be a singleton object.
@@ -111,5 +111,5 @@ final private[borer] class CborRenderer(var out: Output) extends Renderer:
        v += majorType; out
      }).writeByte(v.toByte)
 
-object CborRenderer extends (Output => CborRenderer):
-  def apply(out: Output) = new CborRenderer(out)
+object CborRenderer extends ((Output, Borer.EncodingConfig) => CborRenderer):
+  def apply(out: Output, config: Borer.EncodingConfig) = new CborRenderer(out)