diff options
Diffstat (limited to 'src/math/big/rat_test.go')
| -rw-r--r-- | src/math/big/rat_test.go | 30 |
1 files changed, 26 insertions, 4 deletions
diff --git a/src/math/big/rat_test.go b/src/math/big/rat_test.go index 35bc85c8cd..02569c1b16 100644 --- a/src/math/big/rat_test.go +++ b/src/math/big/rat_test.go @@ -329,18 +329,40 @@ func TestIssue3521(t *testing.T) { t.Errorf("0) got %s want %s", zero.Denom(), one) } - // 1a) a zero value remains zero independent of denominator + // 1a) the denominator of an (uninitialized) zero value is not shared with the value + s := &zero.b + d := zero.Denom() + if d == s { + t.Errorf("1a) got %s (%p) == %s (%p) want different *Int values", d, d, s, s) + } + + // 1b) the denominator of an (uninitialized) value is a new 1 each time + d1 := zero.Denom() + d2 := zero.Denom() + if d1 == d2 { + t.Errorf("1b) got %s (%p) == %s (%p) want different *Int values", d1, d1, d2, d2) + } + + // 1c) the denominator of an initialized zero value is shared with the value x := new(Rat) + x.Set(x) // initialize x (any operation that sets x explicitly will do) + s = &x.b + d = x.Denom() + if d != s { + t.Errorf("1c) got %s (%p) != %s (%p) want identical *Int values", d, d, s, s) + } + + // 1d) a zero value remains zero independent of denominator x.Denom().Set(new(Int).Neg(b)) if x.Cmp(zero) != 0 { - t.Errorf("1a) got %s want %s", x, zero) + t.Errorf("1d) got %s want %s", x, zero) } - // 1b) a zero value may have a denominator != 0 and != 1 + // 1e) a zero value may have a denominator != 0 and != 1 x.Num().Set(a) qab := new(Rat).SetFrac(a, b) if x.Cmp(qab) != 0 { - t.Errorf("1b) got %s want %s", x, qab) + t.Errorf("1e) got %s want %s", x, qab) } // 2a) an integral value becomes a fraction depending on denominator |