Merge pull request #6 from vcaesar/dev

add Error() assert support and IsType() is nil return

Author: vcaesar

assert.go

@@ -76,6 +76,15 @@ func (at *Assertions) NotNil(actual interface{}, args ...interface{}) bool {
 	return NotEqual(at.t, nil, actual, info, call, cinfo)
 }
 
+// Error asserts that not equal error.
+//
+//    at.Error(t *testing.T, err)
+//
+func (at *Assertions) Error(actual interface{}, args ...interface{}) bool {
+	info, call, cinfo := callAdd(Type, args...)
+	return IsType(at.t, "*errors.errorString", actual, info, call, cinfo)
+}
+
 // Empty asserts that empty and objects are equal.
 func (at *Assertions) Empty(actual interface{}, args ...interface{}) bool {
 	info, call, cinfo := typeCall("", actual, args...)

tt.go

@@ -85,6 +85,13 @@ func TypeOf(expect, actual interface{}) bool {
 
 // IsType asserts that two objects type are equal
 func IsType(t TestingT, expect string, actual interface{}, args ...interface{}) bool {
+	if actual == nil && expect == "nil" {
+		return true
+	}
+	if actual == nil {
+		return false
+	}
+
 	s := reflect.TypeOf(actual).String()
 
 	info, call, cinfo := typeCall(expect, s, args...)
@@ -236,6 +243,12 @@ func NotNil(t TestingT, actual interface{}, args ...interface{}) bool {
 	return NotEqual(t, nil, actual, info, call, cinfo)
 }
 
+// Error asserts that equal error.
+func Error(t TestingT, actual interface{}, args ...interface{}) bool {
+	info, call, cinfo := callAdd(Type, args...)
+	return IsType(t, "*errors.errorString", actual, info, call, cinfo)
+}
+
 // Empty asserts that empty and objects are equal.
 func Empty(t TestingT, actual interface{}, args ...interface{}) bool {
 	info, call, cinfo := typeCall("", actual, args...)

tt_test.go

@@ -1,6 +1,7 @@
 package tt
 
 import (
+	"errors"
 	"fmt"
 	"testing"
 
@@ -33,6 +34,8 @@ func TestTT(t *testing.T) {
 	Equal(t, 2, add.Add(1, 1))
 
 	Nil(t, nil)
+	Error(t, errors.New("error new"))
+	IsType(t, "nil", nil)
 	Empty(t, "")
 	Zero(t, 0)
 	Bool(t, 1 == 1)
@@ -121,6 +124,8 @@ func TestArgs(t *testing.T) {
 	at.NotEqual(3, add.Add(1, 1), "", 5)
 
 	at.Nil(nil, "", 4)
+	at.NotNil(1, "", "tt_test.go:127")
+	at.Error(errors.New("error new"), "", "tt_test.go:128")
 	at.Empty("", "", 4)
 	at.Bool(1 == 1, "", 4)
 	at.True(1 == 1, "", 4)