From c8393f8554419dc27b688c535b8fa4afb82146a4 Mon Sep 17 00:00:00 2001
From: Abseil Team <absl-team@google.com>
Date: Mon, 20 May 2024 07:35:58 -0700
Subject: [PATCH] Print mismatches for UnorderedElements() of different sizes.

Changes the behavior of UnorderedElements()/UnorderedElementsAreArray() to print items-without-matchers and matchers-without-items in the case where the actual and expected are different sizes.

PiperOrigin-RevId: 635451316
Change-Id: I2181bb28a14c14cdb577af9268d403e12e942bea
---
 googlemock/src/gmock-matchers.cc              | 27 +++++++++----------
 .../test/gmock-matchers-containers_test.cc    | 17 +++++++++---
 2 files changed, 27 insertions(+), 17 deletions(-)

diff --git a/googlemock/src/gmock-matchers.cc b/googlemock/src/gmock-matchers.cc
index 81a5b7ea5a..277add6b62 100644
--- a/googlemock/src/gmock-matchers.cc
+++ b/googlemock/src/gmock-matchers.cc
@@ -236,9 +236,8 @@ static void LogElementMatcherPairVec(const ElementMatcherPairs& pairs,
   os << "{";
   const char* sep = "";
   for (Iter it = pairs.begin(); it != pairs.end(); ++it) {
-    os << sep << "\n  ("
-       << "element #" << it->first << ", "
-       << "matcher #" << it->second << ")";
+    os << sep << "\n  (" << "element #" << it->first << ", " << "matcher #"
+       << it->second << ")";
     sep = ",";
   }
   os << "\n}";
@@ -374,20 +373,20 @@ bool UnorderedElementsAreMatcherImplBase::VerifyMatchMatrix(
     return true;
   }
 
-  if (match_flags() == UnorderedMatcherRequire::ExactMatch) {
-    if (matrix.LhsSize() != matrix.RhsSize()) {
-      // The element count doesn't match.  If the container is empty,
-      // there's no need to explain anything as Google Mock already
-      // prints the empty container. Otherwise we just need to show
-      // how many elements there actually are.
-      if (matrix.LhsSize() != 0 && listener->IsInterested()) {
-        *listener << "which has " << Elements(matrix.LhsSize());
-      }
-      return false;
+  const bool is_exact_match_with_size_discrepency =
+      match_flags() == UnorderedMatcherRequire::ExactMatch &&
+      matrix.LhsSize() != matrix.RhsSize();
+  if (is_exact_match_with_size_discrepency) {
+    // The element count doesn't match.  If the container is empty,
+    // there's no need to explain anything as Google Mock already
+    // prints the empty container. Otherwise we just need to show
+    // how many elements there actually are.
+    if (matrix.LhsSize() != 0 && listener->IsInterested()) {
+      *listener << "which has " << Elements(matrix.LhsSize()) << "\n";
     }
   }
 
-  bool result = true;
+  bool result = !is_exact_match_with_size_discrepency;
   ::std::vector<char> element_matched(matrix.LhsSize(), 0);
   ::std::vector<char> matcher_matched(matrix.RhsSize(), 0);
 
diff --git a/googlemock/test/gmock-matchers-containers_test.cc b/googlemock/test/gmock-matchers-containers_test.cc
index 38fd9a5dd7..acea4ec357 100644
--- a/googlemock/test/gmock-matchers-containers_test.cc
+++ b/googlemock/test/gmock-matchers-containers_test.cc
@@ -2014,7 +2014,14 @@ TEST_F(UnorderedElementsAreTest, FailMessageCountWrong) {
   StringMatchResultListener listener;
   EXPECT_FALSE(ExplainMatchResult(UnorderedElementsAre(1, 2, 3), v, &listener))
       << listener.str();
-  EXPECT_THAT(listener.str(), Eq("which has 1 element"));
+  EXPECT_THAT(listener.str(),
+              Eq("which has 1 element\n"
+                 "where the following matchers don't match any elements:\n"
+                 "matcher #0: is equal to 1,\n"
+                 "matcher #1: is equal to 2,\n"
+                 "matcher #2: is equal to 3\n"
+                 "and where the following elements don't match any matchers:\n"
+                 "element #0: 4"));
 }
 
 TEST_F(UnorderedElementsAreTest, FailMessageCountWrongZero) {
@@ -2022,7 +2029,11 @@ TEST_F(UnorderedElementsAreTest, FailMessageCountWrongZero) {
   StringMatchResultListener listener;
   EXPECT_FALSE(ExplainMatchResult(UnorderedElementsAre(1, 2, 3), v, &listener))
       << listener.str();
-  EXPECT_THAT(listener.str(), Eq(""));
+  EXPECT_THAT(listener.str(),
+              Eq("where the following matchers don't match any elements:\n"
+                 "matcher #0: is equal to 1,\n"
+                 "matcher #1: is equal to 2,\n"
+                 "matcher #2: is equal to 3"));
 }
 
 TEST_F(UnorderedElementsAreTest, FailMessageUnmatchedMatchers) {
@@ -2438,7 +2449,7 @@ TEST(UnorderedPointwiseTest, RejectsWrongSize) {
   const double lhs[2] = {1, 2};
   const int rhs[1] = {0};
   EXPECT_THAT(lhs, Not(UnorderedPointwise(Gt(), rhs)));
-  EXPECT_EQ("which has 2 elements",
+  EXPECT_EQ("which has 2 elements\n",
             Explain(UnorderedPointwise(Gt(), rhs), lhs));
 
   const int rhs2[3] = {0, 1, 2};