Fix StringFormat garbled output for 5+ placeholders

modules/core/src/main/scala/io/taig/babel/StringFormat.scala

@@ -31,7 +31,7 @@ object StringFormat {
     }
   }
 
-  private[babel] def decoder[A](n: Int)(f: (String, Map[Int, String]) => A): Decoder[A] = Decoder[String].emap {
+  private[babel] def decoder[A](n: Int)(f: (String, List[(Int, String)]) => A): Decoder[A] = Decoder[String].emap {
     (value, path) =>
       val format = parse(value)
       val indices = format.segments.map { case (index, _) => index }
@@ -48,10 +48,10 @@ object StringFormat {
         val offenders = duplicates.mkString(", ")
         val message = s"StringFormat$n may not have duplicate indices, found duplicates for $offenders"
         Left(Decoder.Error(message, path, cause = None))
-      } else Right(f(format.head, format.segments.toMap))
+      } else Right(f(format.head, format.segments))
   }
 
-  private[babel] def build(head: String, segments: Map[Int, String], values: Vector[String]): String = {
+  private[babel] def build(head: String, segments: List[(Int, String)], values: Vector[String]): String = {
     val builder = new StringBuilder(head)
 
     segments.foreach { case (index, segment) =>

modules/tests/shared/src/test/scala/io/taig/babel/StringFormatTest.scala

@@ -38,4 +38,34 @@ final class StringFormatTest extends FunSuite {
   test("decoder has deuplicate placeholders") {
     assert(Decoder[StringFormat2].decode(Babel.Value("lorem {0} dolar {0} amet")).isLeft)
   }
+
+  test("decoder with 5+ placeholders preserves segment order") {
+    val format = Decoder[StringFormat6].decode(
+        Babel.Value("a {0} b {1} c {2} d {3} e {4} f {5} g")
+    )
+    assertEquals(
+        obtained = format.map(_.apply("V0", "V1", "V2", "V3", "V4", "V5")),
+        expected = Right("a V0 b V1 c V2 d V3 e V4 f V5 g")
+    )
+  }
+
+  test("decoder with 5+ placeholders out of order") {
+    val format = Decoder[StringFormat6].decode(
+        Babel.Value("{5} a {3} b {1} c {4} d {0} e {2} f")
+    )
+    assertEquals(
+        obtained = format.map(_.apply("V0", "V1", "V2", "V3", "V4", "V5")),
+        expected = Right("V5 a V3 b V1 c V4 d V0 e V2 f")
+    )
+  }
+
+  test("decoder with 8 placeholders") {
+    val format = Decoder[StringFormat8].decode(
+        Babel.Value("{0}-{1}-{2}-{3}-{4}-{5}-{6}-{7}")
+    )
+    assertEquals(
+        obtained = format.map(_.apply("a", "b", "c", "d", "e", "f", "g", "h")),
+        expected = Right("a-b-c-d-e-f-g-h")
+    )
+  }
 }

modules/tests/shared/src/test/scala/io/taig/babel/generic/DerivationTest.scala

@@ -16,8 +16,8 @@ final class DerivationTest extends FunSuite {
     val foo: Foo = {
 
       val messages: Quantities[StringFormat1] = {
-        val sfOne: StringFormat1 = (v0: String) => StringFormat.build("You clicked ", Map(0 -> " time"), Vector(v0))
-        val sfMany: StringFormat1 = (v0: String) => StringFormat.build("You clicked ", Map(0 -> " times"), Vector(v0))
+        val sfOne: StringFormat1 = (v0: String) => StringFormat.build("You clicked ", List(0 -> " time"), Vector(v0))
+        val sfMany: StringFormat1 = (v0: String) => StringFormat.build("You clicked ", List(0 -> " times"), Vector(v0))
         Quantities.from[StringFormat1](sfMany, List(Quantities.Element(Quantity.One, sfOne)))
       }