Allow passing both float and precision in BigDecimal#div

mrkn · mrkn · commit 900bb7fcf52e · 2021-12-09T21:42:36.000+09:00
Fix GH-212.
diff --git a/ext/bigdecimal/bigdecimal.c b/ext/bigdecimal/bigdecimal.c
@@ -1938,11 +1938,15 @@ BigDecimal_div2(VALUE self, VALUE b, VALUE n)
         Real *res = NULL;
         Real *av = NULL, *bv = NULL, *cv = NULL;
         size_t mx = ix + VpBaseFig()*2;
+        size_t b_prec = ix;
         size_t pl = VpSetPrecLimit(0);
 
         GUARD_OBJ(cv, VpCreateRbObject(mx + VpBaseFig(), "0", true));
         GUARD_OBJ(av, GetVpValue(self, 1));
-        GUARD_OBJ(bv, GetVpValue(b, 1));
+        if (RB_FLOAT_TYPE_P(b) && b_prec > BIGDECIMAL_DOUBLE_FIGURES) {
+            b_prec = BIGDECIMAL_DOUBLE_FIGURES;
+        }
+        GUARD_OBJ(bv, GetVpValueWithPrec(b, b_prec, 1));
         mx = av->Prec + bv->Prec + 2;
         if (mx <= cv->MaxPrec) mx = cv->MaxPrec + 1;
         GUARD_OBJ(res, VpCreateRbObject((mx * 2  + 2)*VpBaseFig(), "#0", true));
diff --git a/test/bigdecimal/test_bigdecimal.rb b/test/bigdecimal/test_bigdecimal.rb
@@ -1091,6 +1091,16 @@ def test_div_bigdecimal
     end
   end
 
+  def test_div_bigdecimal_with_float_and_precision
+    x = BigDecimal(5)
+    y = 5.1
+    assert_equal(x.div(BigDecimal(y, 0), 8),
+                 x.div(y, 8))
+
+    assert_equal(x.div(BigDecimal(y, 0), 100),
+                 x.div(y, 100))
+  end
+
   def test_abs_bigdecimal
     x = BigDecimal((2**100).to_s)
     assert_equal(1267650600228229401496703205376, x.abs)
