From 742fc50ccc1feed562b35256d9111236e2937752 Mon Sep 17 00:00:00 2001
From: Karol Stasiak <karol.m.stasiak@gmail.com>
Date: Tue, 31 Mar 2020 17:58:46 +0200
Subject: [PATCH] Don't used `str2word` as `scrstr2word` when the string
 terminator matches, but digits don't

---
 include/scrstring.mfk                          |  9 ++++++++-
 src/main/scala/millfork/Platform.scala         |  3 +++
 src/main/scala/millfork/parser/TextCodec.scala | 10 ++++++++++
 3 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/include/scrstring.mfk b/include/scrstring.mfk
index e99b88b0..4eee62f2 100644
--- a/include/scrstring.mfk
+++ b/include/scrstring.mfk
@@ -6,7 +6,6 @@ alias scrstrzcmp = strzcmp
 alias scrstrzcopy = strzcopy
 alias scrstrzpaste = strzpaste
 alias scrstrzappendchar = strzappendchar
-alias scrstrz2word = strz2word
 alias scrstrzappend = strzappend
 
 
@@ -27,6 +26,14 @@ void scrstrzappendchar(pointer buffer, byte char) {
    buffer[1] = nullchar_scr
 }
 
+#endif
+
+#if DECIMALS_SAME
+
+alias scrstrz2word = strz2word
+
+#else
+
 word scrstrz2word(pointer str) {
     byte i
     byte char
diff --git a/src/main/scala/millfork/Platform.scala b/src/main/scala/millfork/Platform.scala
index 29d0d093..d176c315 100644
--- a/src/main/scala/millfork/Platform.scala
+++ b/src/main/scala/millfork/Platform.scala
@@ -295,6 +295,9 @@ object Platform {
 
     val builtInFeatures = builtInCpuFeatures(cpu) ++ Map(
       "ENCODING_SAME" -> toLong(codec.name == srcCodec.name),
+      "DECIMALS_SAME" -> toLong(codec.stringTerminator == srcCodec.stringTerminator && ('0' to '9').forall{c =>
+        codec.encodeOneChar(c) == srcCodec.encodeOneChar(c)
+      }),
       "ENCCONV_SUPPORTED" -> toLong((codec.name, srcCodec.name) match {
         case (TextCodec.Petscii.name, TextCodec.CbmScreencodes.name) |
              (TextCodec.PetsciiJp.name, TextCodec.CbmScreencodesJp.name) |
diff --git a/src/main/scala/millfork/parser/TextCodec.scala b/src/main/scala/millfork/parser/TextCodec.scala
index e53739c0..eed934b1 100644
--- a/src/main/scala/millfork/parser/TextCodec.scala
+++ b/src/main/scala/millfork/parser/TextCodec.scala
@@ -21,6 +21,10 @@ sealed trait TextCodec {
 
   def decode(by: Int): Char
 
+  // encodes one char from BMP, without any lookup tables, conversions, and stuff
+  // useful only for things like ASCII digits
+  def encodeOneChar(c: Char): List[Int]
+
   def dump(): Unit = {
     (0 until 256).map(decode).zipWithIndex.grouped(32).map(row => row.head._2.toHexString + "\t" + row.map(_._1).mkString("")).foreach(println(_))
   }
@@ -105,6 +109,10 @@ class UnicodeTextCodec(override val name: String, val charset: Charset, override
     }
   }
 
+  def encodeOneChar(c: Char): List[Int] = {
+    c.toString.getBytes(charset).map(_.&(0xff)).toList
+  }
+
   override def decode(by: Int): Char = {
     if (by >= 0x20 && by <= 0x7E) by.toChar
     else if (by == 0) '.'
@@ -246,6 +254,8 @@ class TableTextCodec(override val name: String,
     val index = by & 0xff
     if (index < map.length) map(index) else TextCodec.NotAChar
   }
+
+  override def encodeOneChar(c: Char): List[Int] = List(map.indexOf(c.toInt))
 }
 
 object TextCodec {