rdf to-jelly: add --delimited option

build.sbt

@@ -6,7 +6,7 @@ resolvers +=
   "Sonatype OSS Snapshots" at "https://s01.oss.sonatype.org/content/repositories/snapshots"
 
 lazy val jenaV = "5.3.0"
-lazy val jellyV = "2.9.1"
+lazy val jellyV = "2.9.1+8-58db074b-SNAPSHOT"
 
 addCommandAlias("fixAll", "scalafixAll; scalafmtAll")
 

src/main/scala/eu/neverblink/jelly/cli/command/rdf/RdfToJelly.scala

@@ -31,6 +31,11 @@ case class RdfToJellyOptions(
         "Default: false",
     )
     enableNamespaceDeclarations: Boolean = false,
+    @HelpMessage(
+      "Whether the output should be delimited. Setting it to false will force the output to be a single " +
+        "frame – make sure you know what you are doing. Default: true",
+    )
+    delimited: Boolean = true,
 ) extends HasJellyCommandOptions
 
 object RdfToJelly extends RdfCommand[RdfToJellyOptions, RdfFormat.Jena.Readable]:
@@ -85,6 +90,7 @@ object RdfToJelly extends RdfCommand[RdfToJellyOptions, RdfFormat.Jena.Readable]
         JellyLanguage.SYMBOL_ENABLE_NAMESPACE_DECLARATIONS,
         getOptions.enableNamespaceDeclarations,
       )
+      .set(JellyLanguage.SYMBOL_DELIMITED_OUTPUT, getOptions.delimited)
     val jellyWriter = StreamRDFWriter.getWriterStream(
       outputStream,
       JellyLanguage.JELLY,

src/test/scala/eu/neverblink/jelly/cli/command/rdf/RdfToJellySpec.scala

@@ -3,7 +3,7 @@ package eu.neverblink.jelly.cli.command.rdf
 import eu.neverblink.jelly.cli.command.helpers.{DataGenHelper, TestFixtureHelper}
 import eu.neverblink.jelly.cli.{ExitException, InvalidArgument, InvalidFormatSpecified}
 import eu.ostrzyciel.jelly.convert.jena.riot.JellyLanguage
-import eu.ostrzyciel.jelly.core.JellyOptions
+import eu.ostrzyciel.jelly.core.{IoUtils, JellyOptions}
 import eu.ostrzyciel.jelly.core.proto.v1.{LogicalStreamType, RdfStreamFrame}
 import org.apache.jena.rdf.model.{Model, ModelFactory}
 import org.apache.jena.riot.{RDFLanguages, RDFParser}
@@ -43,8 +43,10 @@ class RdfToJellySpec extends AnyWordSpec with TestFixtureHelper with Matchers:
       "a file to output stream" in withFullJenaFile { f =>
         val (out, err) =
           RdfToJelly.runTestCommand(List("rdf", "to-jelly", f))
-        val newIn = new ByteArrayInputStream(RdfToJelly.getOutBytes)
-        val content = translateJellyBack(newIn)
+        val bytes = RdfToJelly.getOutBytes
+        // Make sure it's written in the delimited format
+        IoUtils.autodetectDelimiting(new ByteArrayInputStream(bytes))._1 should be(true)
+        val content = translateJellyBack(ByteArrayInputStream(bytes))
         content.containsAll(DataGenHelper.generateTripleModel(testCardinality).listStatements())
       }
 
@@ -187,6 +189,26 @@ class RdfToJellySpec extends AnyWordSpec with TestFixtureHelper with Matchers:
           opts.version should be(2)
         }
       }
+
+      "a file to file, non-delimited output" in withFullJenaFile { f =>
+        withEmptyJellyFile { j =>
+          val (out, err) =
+            RdfToJelly.runTestCommand(
+              List(
+                "rdf",
+                "to-jelly",
+                f,
+                "--delimited=false",
+                "--to",
+                j,
+              ),
+            )
+          val (delimited, is) = IoUtils.autodetectDelimiting(new FileInputStream(j))
+          delimited should be(false)
+          val frame = RdfStreamFrame.parseFrom(is)
+          frame.rows.size should be > 0
+        }
+      }
     }
     "handle conversion of other formats to Jelly" when {
       "NTriples" in {