add label support

src/main/scala/com/htmlism/mos6502/dsl/DslDemo.scala

@@ -113,6 +113,9 @@ class AssemblyContext {
   def push(instruction: Instruction, s: String): Unit =
     xs.append(UnaryInstruction(instruction, s.some))
 
+  def push(s: String): Unit =
+    xs.append(Label(s))
+
   def push[A: Operand](instruction: Instruction, x: A): Unit =
     xs.append(InstructionWithOperand(instruction, x, None))
 

src/main/scala/com/htmlism/mos6502/dsl/Statement.scala

@@ -53,3 +53,11 @@ case class InstructionWithOperand[A](instruction: Instruction, operand: A, comme
   def toTriplet: (String, Option[String], Option[String]) =
     (instruction.toString, ev.toAddressLiteral(operand).some, comment)
 }
+
+case class Label(s: String) extends Statement {
+  def toAsm: String =
+    s + ":"
+
+  def toTriplet: (String, Option[String], Option[String]) =
+    (s, None, None)
+}

src/main/scala/com/htmlism/mos6502/dsl/package.scala

@@ -20,6 +20,10 @@ package object dsl {
       .push(asmCtx.toFragment)
   }
 
+  def label(s: String)(implicit ctx: AssemblyContext): Unit =
+    ctx
+      .push(s)
+
   def group[A](s: String)(f: DefinitionGroupContext => A)(implicit ctx: AsmDocumentContext): A = {
     val g: DefinitionGroupContext =
       new DefinitionGroupContext

src/test/scala/com/htmlism/mos6502/dsl/DslSpec.scala

@@ -126,6 +126,25 @@ class DslSpec extends AnyFlatSpec with should.Matchers {
       )
     )
   }
+
+  "label" should "compile" in {
+    val doc =
+      asmDoc { implicit ctx =>
+        asm { implicit a =>
+          label("init")
+        }
+      }
+
+    doc shouldEqual AsmDocument(
+      List(
+        AsmFragment(
+          List(
+            Label("init")
+          )
+        )
+      )
+    )
+  }
 }
 
 sealed trait Triforce