add support for math/big.Int

_assertauto/Test/MathBigInt/Default.txt

@@ -0,0 +1,6 @@
+[*math/big.Int] => .String() => (len=3) "123"
+	========== assertauto ==========
+[github.com/pierrre/assert/assertauto.allocsPerRun] {
+	Runs: [int] 100,
+	Allocs: [float64] 2,
+}

common.go

@@ -58,6 +58,7 @@ func NewCommonValueWriter() *CommonValueWriter {
 	vw.Stringer = NewStringerValueWriter()
 	vw.Iter = NewIterValueWriter(vw)
 	vw.Kind = NewKindValueWriter(vw)
+	vw.ByTypeValueWriters["*math/big.Int"] = vw.Stringer
 	return vw
 }
 

math_big_test.go

@@ -0,0 +1,14 @@
+package pretty_test
+
+import (
+	"math/big"
+)
+
+func init() {
+	addTestCasesPrefix("MathBigInt", []*testCase{
+		{
+			name:  "Default",
+			value: big.NewInt(123),
+		},
+	})
+}