From b447b6cf0ab35b80fc94f5000c2299ee5680cb50 Mon Sep 17 00:00:00 2001
From: whyrusleeping <why@ipfs.io>
Date: Tue, 5 Nov 2019 10:50:27 -0800
Subject: [PATCH] only trim zeros to the right of the decimal

---
 chain/types/bigint_test.go | 17 +++++++++++++++++
 chain/types/fil.go         |  5 ++++-
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/chain/types/bigint_test.go b/chain/types/bigint_test.go
index 7e2cd71f4..5209e7051 100644
--- a/chain/types/bigint_test.go
+++ b/chain/types/bigint_test.go
@@ -32,3 +32,20 @@ func TestBigIntSerializationRoundTrip(t *testing.T) {
 
 	}
 }
+
+func TestFilRoundTrip(t *testing.T) {
+	testValues := []string{
+		"0", "1", "1.001", "100.10001", "101100", "5000.01", "5000",
+	}
+
+	for _, v := range testValues {
+		fval, err := ParseFIL(v)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		if fval.String() != v {
+			t.Fatal("mismatch in values!", v, fval.String())
+		}
+	}
+}
diff --git a/chain/types/fil.go b/chain/types/fil.go
index f44336fb5..80de6ced3 100644
--- a/chain/types/fil.go
+++ b/chain/types/fil.go
@@ -12,7 +12,10 @@ type FIL BigInt
 
 func (f FIL) String() string {
 	r := new(big.Rat).SetFrac(f.Int, big.NewInt(build.FilecoinPrecision))
-	return strings.TrimRight(r.FloatString(18), "0.")
+	if r.Sign() == 0 {
+		return "0"
+	}
+	return strings.TrimRight(strings.TrimRight(r.FloatString(18), "0"), ".")
 }
 
 func (f FIL) Format(s fmt.State, ch rune) {