Added examples from RFC to test and fixed decode error

punycode.c

@@ -99,7 +99,7 @@ static size_t encode_var_int(const size_t bias, const size_t delta, char *const
 
 static size_t decode_digit(uint32_t v) {
   if (isdigit(v)) {
-    return 22 + (v - '0');
+    return 26 + (v - '0');
   }
   if (islower(v)) {
     return v - 'a';

test-punycode.c

@@ -106,6 +106,54 @@ int main(void) {
     'J', 'a', 'h', 'r', 'e', 's', 0
   };
 
+  /* Examples from RFC */
+  const uint32_t exampleA[] = { 0x0644, 0x064A, 0x0647, 0x0645, 0x0627, 0x0628, 0x062A, 0x0643, 0x0644
+      , 0x0645, 0x0648, 0x0634, 0x0639, 0x0631, 0x0628, 0x064A, 0x061F, 0 };
+  const uint32_t exampleB[] = { 0x4ED6, 0x4EEC, 0x4E3A, 0x4EC0, 0x4E48, 0x4E0D, 0x8BF4, 0x4E2D, 0x6587, 0 };
+  const uint32_t exampleC[] = { 0x4ED6, 0x5011, 0x7232, 0x4EC0, 0x9EBD, 0x4E0D, 0x8AAA, 0x4E2D, 0x6587, 0 };
+  const uint32_t exampleD[] = { 0x0050, 0x0072, 0x006F, 0x010D, 0x0070, 0x0072, 0x006F, 0x0073, 0x0074
+      , 0x011B, 0x006E, 0x0065, 0x006D, 0x006C, 0x0075, 0x0076, 0x00ED, 0x010D
+      , 0x0065, 0x0073, 0x006B, 0x0079, 0 };
+  const uint32_t exampleE[] = { 0x05DC, 0x05DE, 0x05D4, 0x05D4, 0x05DD, 0x05E4, 0x05E9, 0x05D5, 0x05D8
+      , 0x05DC, 0x05D0, 0x05DE, 0x05D3, 0x05D1, 0x05E8, 0x05D9, 0x05DD, 0x05E2
+      , 0x05D1, 0x05E8, 0x05D9, 0x05EA, 0 };
+  const uint32_t exampleF[] = { 0x092F, 0x0939, 0x0932, 0x094B, 0x0917, 0x0939, 0x093F, 0x0928, 0x094D
+      , 0x0926, 0x0940, 0x0915, 0x094D, 0x092F, 0x094B, 0x0902, 0x0928, 0x0939
+      , 0x0940, 0x0902, 0x092C, 0x094B, 0x0932, 0x0938, 0x0915, 0x0924, 0x0947
+      , 0x0939, 0x0948, 0x0902, 0 };
+  const uint32_t exampleG[] = { 0x306A, 0x305C, 0x307F, 0x3093, 0x306A, 0x65E5, 0x672C, 0x8A9E, 0x3092
+      , 0x8A71, 0x3057, 0x3066, 0x304F, 0x308C, 0x306A, 0x3044, 0x306E, 0x304B, 0 };
+  const uint32_t exampleH[] = { 0xC138, 0xACC4, 0xC758, 0xBAA8, 0xB4E0, 0xC0AC, 0xB78C, 0xB4E4, 0xC774
+      , 0xD55C, 0xAD6D, 0xC5B4, 0xB97C, 0xC774, 0xD574, 0xD55C, 0xB2E4, 0xBA74
+      , 0xC5BC, 0xB9C8, 0xB098, 0xC88B, 0xC744, 0xAE4C, 0 };
+ const uint32_t exampleI[] = { 0x043F, 0x043E, 0x0447, 0x0435, 0x043C, 0x0443, 0x0436, 0x0435, 0x043E
+      , 0x043D, 0x0438, 0x043D, 0x0435, 0x0433, 0x043E, 0x0432, 0x043E, 0x0440
+      , 0x044F, 0x0442, 0x043F, 0x043E, 0x0440, 0x0443, 0x0441, 0x0441, 0x043A
+      , 0x0438, 0 };
+  const uint32_t exampleJ[] = { 0x0050, 0x006F, 0x0072, 0x0071, 0x0075, 0x00E9, 0x006E, 0x006F, 0x0070
+      , 0x0075, 0x0065, 0x0064, 0x0065, 0x006E, 0x0073, 0x0069, 0x006D, 0x0070
+      , 0x006C, 0x0065, 0x006D, 0x0065, 0x006E, 0x0074, 0x0065, 0x0068, 0x0061
+      , 0x0062, 0x006C, 0x0061, 0x0072, 0x0065, 0x006E, 0x0045, 0x0073, 0x0070
+      , 0x0061, 0x00F1, 0x006F, 0x006C, 0 };
+  const uint32_t exampleK[] = { 0x0054, 0x1EA1, 0x0069, 0x0073, 0x0061, 0x006F, 0x0068, 0x1ECD, 0x006B
+      , 0x0068, 0x00F4, 0x006E, 0x0067, 0x0074, 0x0068, 0x1EC3, 0x0063, 0x0068
+      , 0x1EC9, 0x006E, 0x00F3, 0x0069, 0x0074, 0x0069, 0x1EBF, 0x006E, 0x0067
+      , 0x0056, 0x0069, 0x1EC7, 0x0074, 0 };
+  const uint32_t exampleL[] = { 0x0033, 0x5E74, 0x0042, 0x7D44, 0x91D1, 0x516B, 0x5148, 0x751F, 0 };
+  const uint32_t exampleM[] = { 0x5B89, 0x5BA4, 0x5948, 0x7F8E, 0x6075, 0x002D, 0x0077, 0x0069, 0x0074
+      , 0x0068, 0x002D, 0x0053, 0x0055, 0x0050, 0x0045, 0x0052, 0x002D, 0x004D
+      , 0x004F, 0x004E, 0x004B, 0x0045, 0x0059, 0x0053, 0 };
+  const uint32_t exampleN[] = { 0x0048, 0x0065, 0x006C, 0x006C, 0x006F, 0x002D, 0x0041, 0x006E, 0x006F
+      , 0x0074, 0x0068, 0x0065, 0x0072, 0x002D, 0x0057, 0x0061, 0x0079, 0x002D
+      , 0x305D, 0x308C, 0x305E, 0x308C, 0x306E, 0x5834, 0x6240, 0 };
+  const uint32_t exampleO[] = { 0x3072, 0x3068, 0x3064, 0x5C4B, 0x6839, 0x306E, 0x4E0B, 0x0032, 0 };
+  const uint32_t exampleP[] = { 0x004D, 0x0061, 0x006A, 0x0069, 0x3067, 0x004B, 0x006F, 0x0069, 0x3059
+      , 0x308B, 0x0035, 0x79D2, 0x524D, 0 };
+  const uint32_t exampleQ[] = { 0x30D1, 0x30D5, 0x30A3, 0x30FC, 0x0064, 0x0065, 0x30EB, 0x30F3, 0x30D0, 0 };
+  const uint32_t exampleR[] = { 0x305D, 0x306E, 0x30B9, 0x30D4, 0x30FC, 0x30C9, 0x3067, 0 };
+  const uint32_t exampleS[] = { 0x002D, 0x003E, 0x0020, 0x0024, 0x0031, 0x002E, 0x0030, 0x0030, 0x0020
+      , 0x003C, 0x002D, 0 };
+
   struct {
     const uint32_t *unicode;
     const char *punycode;
@@ -115,6 +163,25 @@ int main(void) {
     { stanza1, "Bach-" },
     { stanza2, "bcher-kva" },
     { stanza3, "Willst du die Blthe des frhen, die Frchte des spteren Jahres-x9e96lkal" },
+    { exampleA, "egbpdaj6bu4bxfgehfvwxn" },
+    { exampleB, "ihqwcrb4cv8a8dqg056pqjye"},
+    { exampleC, "ihqwctvzc91f659drss3x8bo0yb"},
+    { exampleD, "Proprostnemluvesky-uyb24dma41a"},
+    { exampleE, "4dbcagdahymbxekheh6e0a7fei0b"},
+    { exampleF, "i1baa7eci9glrd9b2ae1bj0hfcgg6iyaf8o0a1dig0cd"},
+    { exampleG, "n8jok5ay5dzabd5bym9f0cm5685rrjetr6pdxa"},
+    { exampleH, "989aomsvi5e83db1d2a355cv1e0vak1dwrv93d5xbh15a0dt30a5jpsd879ccm6fea98c"},
+    { exampleI, "b1abfaaepdrnnbgefbadotcwatmq2g4l"},
+    { exampleJ, "PorqunopuedensimplementehablarenEspaol-fmd56a"},
+    { exampleK, "TisaohkhngthchnitingVit-kjcr8268qyxafd2f1b9g"},
+    { exampleL, "3B-ww4c5e180e575a65lsy2b"},
+    { exampleM, "-with-SUPER-MONKEYS-pc58ag80a8qai00g7n9n"},
+    { exampleN, "Hello-Another-Way--fc4qua05auwb3674vfr0b"},
+    { exampleO, "2-u9tlzr9756bt3uc0v"},
+    { exampleP, "MajiKoi5-783gue6qz075azm5e"},
+    { exampleQ, "de-jg4avhby1noc0d"},
+    { exampleR, "d9juau41awczczp"},
+    { exampleS, "-> $1.00 <--"}
   };
 
   unsigned i;