From 64941b99e2bfbaf6f1c1fcfefd51d055beaafcbf Mon Sep 17 00:00:00 2001
From: Thomas Pelletier <pelletier.thomas@gmail.com>
Date: Mon, 25 Oct 2021 15:55:54 -0400
Subject: [PATCH] unmarshal: empty document results in map (#640)

Fixes #602
---
 unmarshaler.go      |  8 +++++++-
 unmarshaler_test.go | 10 ++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/unmarshaler.go b/unmarshaler.go
index 19efaa4..6e3abc6 100644
--- a/unmarshaler.go
+++ b/unmarshaler.go
@@ -174,7 +174,13 @@ func (d *decoder) FromParser(v interface{}) error {
 		return fmt.Errorf("toml: decoding pointer target cannot be nil")
 	}
 
-	err := d.fromParser(r.Elem())
+	r = r.Elem()
+	if r.Kind() == reflect.Interface && r.IsNil() {
+		newMap := map[string]interface{}{}
+		r.Set(reflect.ValueOf(newMap))
+	}
+
+	err := d.fromParser(r)
 	if err == nil {
 		return d.strict.Error(d.p.data)
 	}
diff --git a/unmarshaler_test.go b/unmarshaler_test.go
index 4374d87..362e937 100644
--- a/unmarshaler_test.go
+++ b/unmarshaler_test.go
@@ -1800,6 +1800,16 @@ func TestIssue596(t *testing.T) {
 	require.Error(t, err)
 }
 
+func TestIssue602(t *testing.T) {
+	var v interface{}
+	err := toml.Unmarshal([]byte(""), &v)
+	require.NoError(t, err)
+
+	var expected interface{} = map[string]interface{}{}
+
+	require.Equal(t, expected, v)
+}
+
 //nolint:funlen
 func TestUnmarshalDecodeErrors(t *testing.T) {
 	examples := []struct {