bahaghari/lib: update hex subset to properly accept inputs with mixed letter cases

subprojects/bahaghari/lib/hex.nix

@@ -27,10 +27,37 @@ let
   baseSet = self.generateBaseDigitType glyphList;
 in
 rec {
-  /* Returns a convenient glyph set for creating your own conversion or
+  inherit (baseSet) glyphSet conversionTable;
-     hex-related functions.
+
+  /* Converts a hexadecimal digit string into its decimal equivalent.
+
+     Type: toDec :: String -> Number
+
+     Example:
+       toDec "FF"
+       => 255
+
+       toDec "ff"
+       => 255
   */
-  inherit (baseSet) glyphSet conversionTable fromDec toDec;
+  toDec = digit:
+    let
+      digit' = lib.toUpper digit;
+    in
+      baseSet.toDec digit';
+
+  /* Converts a decimal digit into its hexadecimal notation.
+
+     Type: fromDec :: Number -> String
+
+     Example:
+       fromDec 255
+       => "FF"
+
+       fromDec 293454837
+       => "117DC3F5"
+  */
+  fromDec = decimal: lib.toUpper (baseSet.fromDec decimal);
 
   /* A variant of `lib.lists.range` function just with hexadecimal digits.
 

subprojects/bahaghari/tests/lib/hex.nix

@@ -41,6 +41,16 @@ lib.runTests {
     expected = 2565;
   };
 
+  testHexToDecLowercase = {
+    expr = self.hex.toDec "0A0FfbA";
+    expected = 10551226;
+  };
+
+  testHexToDecLowercase2 = {
+    expr = self.hex.toDec "0af";
+    expected = 175;
+  };
+
   testCreateHexRange = {
     expr = self.hex.range 10 17;
     expected = [ "A" "B" "C" "D" "E" "F" "10" "11" ];
@@ -75,4 +85,9 @@ lib.runTests {
     expr = self.hex.pad (-5) "A42C";
     expected = "A42C";
   };
+
+  testHexPadWithMixedLetterCase = {
+    expr = self.hex.pad 8 "AfB9";
+    expected = "0000AfB9";
+  };
 }