hugeint conversion

Author: jraymakers

bindings/src/duckdb_node_bindings.cpp

@@ -1230,14 +1230,33 @@ class DuckDBNodeAddon : public Napi::Addon<DuckDBNodeAddon> {
   // function hugeint_to_double(hugeint: bigint): number
   Napi::Value hugeint_to_double(const Napi::CallbackInfo& info) {
     auto env = info.Env();
-    throw Napi::Error::New(env, "Not implemented yet");
+    auto hugeint_as_bigint = info[0].As<Napi::BigInt>();
+    int sign_bit;
+    size_t word_count = 2;
+    uint64_t words[2];
+    hugeint_as_bigint.ToWords(&sign_bit, &word_count, words);
+    if (word_count > 2) {
+      throw Napi::Error::New(env, "bigint out of hugeint range");
+    }
+    uint64_t lower = word_count > 0 ? (sign_bit ? -1 : 1) * words[0] : 0;
+    int64_t upper = word_count > 1 ? (sign_bit ? -1 : 1) * words[1] : (word_count > 0 && sign_bit ? -1 : 0);
+    duckdb_hugeint hugeint = { lower, upper };
+    auto output_double = duckdb_hugeint_to_double(hugeint);
+    return Napi::Number::New(env, output_double);
   }
 
   // DUCKDB_API duckdb_hugeint duckdb_double_to_hugeint(double val);
   // function double_to_hugeint(double: number): bigint
   Napi::Value double_to_hugeint(const Napi::CallbackInfo& info) {
     auto env = info.Env();
-    throw Napi::Error::New(env, "Not implemented yet");
+    auto input_double = info[0].As<Napi::Number>().DoubleValue();
+    auto hugeint = duckdb_double_to_hugeint(input_double);
+    int sign_bit = input_double < 0 ? 1 : 0;
+    size_t word_count = hugeint.upper == -1 ? 1 : 2;
+    uint64_t words[2];
+    words[0] = (sign_bit ? -1 : 1) * hugeint.lower;
+    words[1] = (sign_bit ? -1 : 1) * hugeint.upper;
+    return Napi::BigInt::New(env, sign_bit, word_count, words);
   }
 
   // DUCKDB_API double duckdb_uhugeint_to_double(duckdb_uhugeint val);

bindings/test/conversion.test.ts

@@ -178,4 +178,71 @@ suite('conversion', () => {
       expect(duckdb.is_finite_timestamp({ micros: -(2n ** 63n - 1n) })).toBe(false);
     });
   });
+  suite('hugeint_to_double', () => {
+    test('one', () => {
+      expect(duckdb.hugeint_to_double(1n)).toBe(1);
+    });
+    test('zero', () => {
+      expect(duckdb.hugeint_to_double(0n)).toBe(0);
+    });
+    test('negative one', () => {
+      expect(duckdb.hugeint_to_double(-1n)).toBe(-1);
+    });
+    test('one word', () => {
+      expect(duckdb.hugeint_to_double(2n ** 63n)).toBe(9.223372036854776e+18);
+    });
+    test('two words', () => {
+      expect(duckdb.hugeint_to_double(2n ** 65n)).toBe(3.6893488147419103e+19);
+    });
+    test('negative one word', () => {
+      expect(duckdb.hugeint_to_double(-(2n ** 63n))).toBe(-9.223372036854776e+18);
+    });
+    test('negative two words', () => {
+      expect(duckdb.hugeint_to_double(-(2n ** 65n))).toBe(-3.6893488147419103e+19);
+    });
+    test('min', () => {
+      expect(duckdb.hugeint_to_double(-(2n ** 127n - 1n))).toBe(-1.7014118346046923e+38);
+    });
+    test('max', () => {
+      expect(duckdb.hugeint_to_double(2n ** 127n - 1n)).toBe(1.7014118346046923e+38);
+    });
+    test('near min', () => {
+      expect(duckdb.hugeint_to_double(-(2n ** 127n - 2n ** 74n))).toBe(-1.7014118346046922e+38);
+    });
+    test('near max', () => {
+      expect(duckdb.hugeint_to_double(2n ** 127n - 2n ** 74n)).toBe(1.7014118346046922e+38);
+    });
+    test('out of range', () => {
+      expect(() => duckdb.hugeint_to_double(2n ** 129n)).toThrowError('bigint out of hugeint range');
+    });
+  });
+  suite('double_to_hugeint', () => {
+    test('one', () => {
+      expect(duckdb.double_to_hugeint(1)).toBe(1n);
+    });
+    test('zero', () => {
+      expect(duckdb.double_to_hugeint(0)).toBe(0n);
+    });
+    test('negative one', () => {
+      expect(duckdb.double_to_hugeint(-1)).toBe(-1n);
+    });
+    test('one word', () => {
+      expect(duckdb.double_to_hugeint(9.223372036854776e+18)).toBe(2n ** 63n);
+    });
+    test('two words', () => {
+      expect(duckdb.double_to_hugeint(3.6893488147419103e+19)).toBe(2n ** 65n);
+    });
+    test('negative one word', () => {
+      expect(duckdb.double_to_hugeint(-9.223372036854776e+18)).toBe(-(2n ** 63n));
+    });
+    test('negative two words', () => {
+      expect(duckdb.double_to_hugeint(-3.6893488147419103e+19)).toBe(-(2n ** 65n));
+    });
+    test('near min', () => {
+      expect(duckdb.double_to_hugeint(-1.7014118346046922e+38)).toBe(-(2n ** 127n - 2n ** 74n));
+    });
+    test('near max', () => {
+      expect(duckdb.double_to_hugeint(1.7014118346046922e+38)).toBe(2n ** 127n - 2n ** 74n);
+    });
+  });
 });