diff --git a/src/google/protobuf/stubs/strutil.cc b/src/google/protobuf/stubs/strutil.cc
index 5486887295..06250b1dd3 100644
--- a/src/google/protobuf/stubs/strutil.cc
+++ b/src/google/protobuf/stubs/strutil.cc
@@ -80,21 +80,6 @@ inline bool isprint(char c) {
   return c >= 0x20 && c <= 0x7E;
 }
 
-// ----------------------------------------------------------------------
-// StripString
-//    Replaces any occurrence of the character 'remove' (or the characters
-//    in 'remove') with the character 'replacewith'.
-// ----------------------------------------------------------------------
-void StripString(string* s, const char* remove, char replacewith) {
-  const char * str_start = s->c_str();
-  const char * str = str_start;
-  for (str = strpbrk(str, remove);
-       str != nullptr;
-       str = strpbrk(str + 1, remove)) {
-    (*s)[str - str_start] = replacewith;
-  }
-}
-
 // ----------------------------------------------------------------------
 // ReplaceCharacters
 //    Replaces any occurrence of the character 'remove' (or the characters
diff --git a/src/google/protobuf/stubs/strutil.h b/src/google/protobuf/stubs/strutil.h
index 790500d26e..e28d22ec8b 100644
--- a/src/google/protobuf/stubs/strutil.h
+++ b/src/google/protobuf/stubs/strutil.h
@@ -159,8 +159,6 @@ inline string StripSuffixString(const string& str, const string& suffix) {
 // ----------------------------------------------------------------------
 PROTOBUF_EXPORT void ReplaceCharacters(string* s, const char* remove,
                                        char replacewith);
-PROTOBUF_EXPORT void StripString(string* s, const char* remove,
-                                 char replacewith);
 
 PROTOBUF_EXPORT void StripWhitespace(string* s);
 
diff --git a/src/google/protobuf/stubs/strutil_unittest.cc b/src/google/protobuf/stubs/strutil_unittest.cc
index f830e37704..07d16efacd 100644
--- a/src/google/protobuf/stubs/strutil_unittest.cc
+++ b/src/google/protobuf/stubs/strutil_unittest.cc
@@ -836,6 +836,50 @@ TEST(StrCat, Ints) {
   EXPECT_EQ(answer, "130");
 }
 
+class ReplaceChars : public ::testing::TestWithParam<std::tuple<string, string, const char*, char>> {
+};
+
+TEST_P(ReplaceChars, ReplacesAllOccurencesOfAnyCharInReplaceWithAReplaceChar) {
+    string expected = std::get<0>(GetParam());
+    string string_to_replace_in = std::get<1>(GetParam());
+    const char* what_to_replace = std::get<2>(GetParam());
+    char replacement = std::get<3>(GetParam());
+    ReplaceCharacters(&string_to_replace_in, what_to_replace, replacement);
+    ASSERT_EQ(expected, string_to_replace_in);
+}
+
+INSTANTIATE_TEST_CASE_P(Replace,
+    ReplaceChars,
+    ::testing::Values(
+        std::make_tuple("", "", "", '_'), // empty string should remain empty
+        std::make_tuple(" ", " ", "", '_'), // no replacement string
+        std::make_tuple(" ", " ", "_-abcedf", '*'), // replacement character not in string
+        std::make_tuple("replace", "Replace", "R", 'r'), // replace one character
+        std::make_tuple("not_spaces__", "not\nspaces\t ", " \t\r\n", '_'), // replace some special characters
+        std::make_tuple("c++", "cxx", "x", '+'), // same character multiple times
+        std::make_tuple("qvvvvvng v T", "queueing a T", "aeiou", 'v'))); // replace all voewls
+
+class StripWs: public ::testing::TestWithParam<std::tuple<string, string>> {
+};
+
+TEST_P(StripWs, AlwaysStripsLeadingAndTrailingWhitespace) {
+    string expected = std::get<0>(GetParam());
+    string string_to_strip = std::get<1>(GetParam());
+    StripWhitespace(&string_to_strip);
+    ASSERT_EQ(expected, string_to_strip);
+}
+
+INSTANTIATE_TEST_CASE_P(Strip,
+    StripWs,
+    ::testing::Values(
+        std::make_tuple("", ""), // empty string should remain empty
+        std::make_tuple("", " "), // only ws should become empty
+        std::make_tuple("no whitespace", " no whitespace"), // leading ws removed
+        std::make_tuple("no whitespace", "no whitespace "), // trailing ws removed
+        std::make_tuple("no whitespace", " no whitespace "), // same nb. of leading and trailing
+        std::make_tuple("no whitespace", "  no whitespace "), // different nb. of leading/trailing
+        std::make_tuple("no whitespace", " no whitespace  "))); // more trailing than leading
+
 }  // anonymous namespace
 }  // namespace protobuf
 }  // namespace google