From 42afde47afb5a116d5d2d42cbab8d6ea8d38c520 Mon Sep 17 00:00:00 2001
From: Brandon Bodnar <33429657+brandonbodnar-wk@users.noreply.github.com>
Date: Mon, 17 Sep 2018 07:37:43 -0500
Subject: [PATCH] Introduce unexported match method to report errors matching

Changes to the method signature for argumentMatcher.Matches may lead to breaking existing
external uses of that function. Introducing a  new method used internally allows presenting
the error information out for internal testify functionality while not breaking other
existing uses of Matches.
---
 mock/mock.go | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/mock/mock.go b/mock/mock.go
index 3b4a31f..c47696d 100644
--- a/mock/mock.go
+++ b/mock/mock.go
@@ -580,7 +580,11 @@ type argumentMatcher struct {
 	fn reflect.Value
 }
 
-func (f argumentMatcher) Matches(argument interface{}) error {
+func (f argumentMatcher) Matches(argument interface{}) bool {
+	return f.match(argument) == nil
+}
+
+func (f argumentMatcher) match(argument interface{}) error {
 	expectType := f.fn.Type().In(0)
 	expectTypeNilSupported := false
 	switch expectType.Kind() {
@@ -718,7 +722,7 @@ func (args Arguments) Diff(objects []interface{}) (string, int) {
 		}
 
 		if matcher, ok := expected.(argumentMatcher); ok {
-			if matchError := matcher.Matches(actual); matchError == nil {
+			if matchError := matcher.match(actual); matchError == nil {
 				output = fmt.Sprintf("%s\t%d: PASS:  %s matched by %s\n", output, i, actualFmt, matcher)
 			} else {
 				differences++