Fix big_integer literal parsing

NilFoundation · Nov 4, 2024 · 656991a · 656991a
1 parent f092a28
commit 656991a
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Showing 2 changed files with 14 additions and 8 deletions.
diff --git a/crypto3/libs/multiprecision/include/nil/crypto3/multiprecision/big_integer/literals.hpp b/crypto3/libs/multiprecision/include/nil/crypto3/multiprecision/big_integer/literals.hpp
@@ -38,26 +38,26 @@ namespace nil::crypto3::multiprecision::literals {
                 if (!is_valid_hex_digit(c)) {
                     throw std::invalid_argument("non hex character in literal");
                 }
-                int digit = parse_hex_digit(c);
                 result <<= 4;
                 if (bits != 0) {
                     bits += 4;
                 }
-                result += parse_hex_digit(c);
-                if (digit != 0) {
+                int digit = parse_hex_digit(c);
+                result += digit;
+                if (bits == 0 && digit != 0) {
                     if (digit >= 8) {
-                        bits = 4;
+                        bits += 4;
                     } else if (digit >= 4) {
-                        bits = 3;
+                        bits += 3;
                     } else if (digit >= 2) {
-                        bits = 2;
+                        bits += 2;
                     } else {
-                        bits = 1;
+                        bits += 1;
                     }
                 }
             }
             if (bits > Bits) {
-                throw "not enough bits to store literal";
+                throw std::invalid_argument("not enough bits to store literal");
             }
             return result;
         }

diff --git a/crypto3/libs/multiprecision/test/big_integer.cpp b/crypto3/libs/multiprecision/test/big_integer.cpp
@@ -17,6 +17,7 @@ CRYPTO3_MP_DEFINE_BIG_INTEGER_LITERAL(32)
 CRYPTO3_MP_DEFINE_BIG_INTEGER_LITERAL(33)
 CRYPTO3_MP_DEFINE_BIG_INTEGER_LITERAL(36)
 CRYPTO3_MP_DEFINE_BIG_INTEGER_LITERAL(37)
+CRYPTO3_MP_DEFINE_BIG_INTEGER_LITERAL(85)
 BOOST_MP_DEFINE_SIZED_CPP_INT_LITERAL(60)
 
 using namespace nil::crypto3::multiprecision::literals;
@@ -32,6 +33,11 @@ BOOST_AUTO_TEST_CASE(to_string_trivial) { BOOST_CHECK_EQUAL((0x1_big_integer60).
 
 BOOST_AUTO_TEST_CASE(to_string_small) { BOOST_CHECK_EQUAL((0x20_big_integer60).str(), "0x20"); }
 
+BOOST_AUTO_TEST_CASE(to_string_medium) {
+    constexpr auto a = 0x123456789ABCDEF1234321_big_integer85;
+    BOOST_CHECK_EQUAL(a.str(), "0x123456789ABCDEF1234321");
+}
+
 BOOST_AUTO_TEST_CASE(ops) {
     nil::crypto3::multiprecision::big_integer<60> a = 2u, b;