1 files changed, 337 insertions, 0 deletions
diff --git a/clang-tools-extra/test/clang-tidy/bugprone-suspicious-string-compare.cpp b/clang-tools-extra/test/clang-tidy/bugprone-suspicious-string-compare.cpp
new file mode 100644
index 00000000000..c1c24ffcd44
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/bugprone-suspicious-string-compare.cpp
@@ -0,0 +1,337 @@
+// RUN: %check_clang_tidy %s bugprone-suspicious-string-compare %t -- \
+// RUN: -config='{CheckOptions: \
+// RUN:  [{key: bugprone-suspicious-string-compare.WarnOnImplicitComparison, value: 1}, \
+// RUN:   {key: bugprone-suspicious-string-compare.WarnOnLogicalNotComparison, value: 1}]}' \
+// RUN: --
+
+typedef __SIZE_TYPE__ size;
+
+struct locale_t {
+  void* dummy;
+} locale;
+
+static const char A[] = "abc";
+static const unsigned char U[] = "abc";
+static const unsigned char V[] = "xyz";
+static const wchar_t W[] = L"abc";
+
+int strlen(const char *);
+
+int memcmp(const void *, const void *, size);
+int wmemcmp(const wchar_t *, const wchar_t *, size);
+int memicmp(const void *, const void *, size);
+int _memicmp(const void *, const void *, size);
+int _memicmp_l(const void *, const void *, size, locale_t);
+
+int strcmp(const char *, const char *);
+int strncmp(const char *, const char *, size);
+int strcasecmp(const char *, const char *);
+int strncasecmp(const char *, const char *, size);
+int stricmp(const char *, const char *);
+int strcmpi(const char *, const char *);
+int strnicmp(const char *, const char *, size);
+int _stricmp(const char *, const char * );
+int _strnicmp(const char *, const char *, size);
+int _stricmp_l(const char *, const char *, locale_t);
+int _strnicmp_l(const char *, const char *, size, locale_t);
+
+int wcscmp(const wchar_t *, const wchar_t *);
+int wcsncmp(const wchar_t *, const wchar_t *, size);
+int wcscasecmp(const wchar_t *, const wchar_t *);
+int wcsicmp(const wchar_t *, const wchar_t *);
+int wcsnicmp(const wchar_t *, const wchar_t *, size);
+int _wcsicmp(const wchar_t *, const wchar_t *);
+int _wcsnicmp(const wchar_t *, const wchar_t *, size);
+int _wcsicmp_l(const wchar_t *, const wchar_t *, locale_t);
+int _wcsnicmp_l(const wchar_t *, const wchar_t *, size, locale_t);
+
+int _mbscmp(const unsigned char *, const unsigned char *);
+int _mbsncmp(const unsigned char *, const unsigned char *, size);
+int _mbsnbcmp(const unsigned char *, const unsigned char *, size);
+int _mbsnbicmp(const unsigned char *, const unsigned char *, size);
+int _mbsicmp(const unsigned char *, const unsigned char *);
+int _mbsnicmp(const unsigned char *, const unsigned char *, size);
+int _mbscmp_l(const unsigned char *, const unsigned char *, locale_t);
+int _mbsncmp_l(const unsigned char *, const unsigned char *, size, locale_t);
+int _mbsicmp_l(const unsigned char *, const unsigned char *, locale_t);
+int _mbsnicmp_l(const unsigned char *, const unsigned char *, size, locale_t);
+int _mbsnbcmp_l(const unsigned char *, const unsigned char *, size, locale_t);
+int _mbsnbicmp_l(const unsigned char *, const unsigned char *, size, locale_t);
+
+int test_warning_patterns() {
+  if (strcmp(A, "a"))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'strcmp' is called without explicitly comparing result [bugprone-suspicious-string-compare]
+  // CHECK-FIXES: if (strcmp(A, "a") != 0)
+
+  if (strcmp(A, "a") == 0 ||
+      strcmp(A, "b"))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'strcmp' is called without explicitly comparing result
+  // CHECK-FIXES: strcmp(A, "b") != 0)
+
+  if (strcmp(A, "a") == 1)
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'strcmp' is compared to a suspicious constant
+
+  if (strcmp(A, "a") == -1)
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'strcmp' is compared to a suspicious constant
+
+  if (strcmp(A, "a") == true)
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'strcmp' is compared to a suspicious constant
+
+  if (strcmp(A, "a") < '0')
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'strcmp' is compared to a suspicious constant
+
+  if (strcmp(A, "a") < 0.)
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'strcmp' has suspicious implicit cast
+}
+
+int test_valid_patterns() {
+  // The following cases are valid.
+  if (strcmp(A, "a") < 0)
+    return 0;
+  if (strcmp(A, "a") == 0)
+    return 0;
+  if (strcmp(A, "a") <= 0)
+    return 0;
+
+  if (wcscmp(W, L"a") < 0)
+    return 0;
+  if (wcscmp(W, L"a") == 0)
+    return 0;
+  if (wcscmp(W, L"a") <= 0)
+    return 0;
+
+  return 1;
+}
+
+int test_implicit_compare_with_functions() {
+
+  if (memcmp(A, "a", 1))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'memcmp' is called without explicitly comparing result
+  // CHECK-FIXES: memcmp(A, "a", 1) != 0)
+
+  if (wmemcmp(W, L"a", 1))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'wmemcmp' is called without explicitly comparing result
+  // CHECK-FIXES: wmemcmp(W, L"a", 1) != 0)
+
+  if (memicmp(A, "a", 1))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'memicmp' is called without explicitly comparing result
+  // CHECK-FIXES: memicmp(A, "a", 1) != 0)
+
+  if (_memicmp(A, "a", 1))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_memicmp' is called without explicitly comparing result
+  // CHECK-FIXES: _memicmp(A, "a", 1) != 0)
+
+  if (_memicmp_l(A, "a", 1, locale))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_memicmp_l' is called without explicitly comparing result
+  // CHECK-FIXES: _memicmp_l(A, "a", 1, locale) != 0)
+
+  if (strcmp(A, "a"))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'strcmp' is called without explicitly comparing result
+  // CHECK-FIXES: strcmp(A, "a") != 0)
+
+  if (strncmp(A, "a", 1))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'strncmp' is called without explicitly comparing result
+  // CHECK-FIXES: strncmp(A, "a", 1) != 0)
+
+  if (strcasecmp(A, "a"))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'strcasecmp' is called without explicitly comparing result
+  // CHECK-FIXES: strcasecmp(A, "a") != 0)
+
+  if (strncasecmp(A, "a", 1))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'strncasecmp' is called without explicitly comparing result
+  // CHECK-FIXES: strncasecmp(A, "a", 1) != 0)
+
+  if (stricmp(A, "a"))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'stricmp' is called without explicitly comparing result
+  // CHECK-FIXES: stricmp(A, "a") != 0)
+
+  if (strcmpi(A, "a"))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'strcmpi' is called without explicitly comparing result
+  // CHECK-FIXES: strcmpi(A, "a") != 0)
+
+  if (_stricmp(A, "a"))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_stricmp' is called without explicitly comparing result
+  // CHECK-FIXES: _stricmp(A, "a") != 0)
+
+  if (strnicmp(A, "a", 1))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'strnicmp' is called without explicitly comparing result
+  // CHECK-FIXES: strnicmp(A, "a", 1) != 0)
+
+  if (_strnicmp(A, "a", 1))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_strnicmp' is called without explicitly comparing result
+  // CHECK-FIXES: _strnicmp(A, "a", 1) != 0)
+
+  if (_stricmp_l(A, "a", locale))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_stricmp_l' is called without explicitly comparing result
+  // CHECK-FIXES: _stricmp_l(A, "a", locale) != 0)
+
+  if (_strnicmp_l(A, "a", 1, locale))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_strnicmp_l' is called without explicitly comparing result
+  // CHECK-FIXES: _strnicmp_l(A, "a", 1, locale) != 0)
+
+  if (wcscmp(W, L"a"))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'wcscmp' is called without explicitly comparing result
+  // CHECK-FIXES: wcscmp(W, L"a") != 0)
+
+  if (wcsncmp(W, L"a", 1))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'wcsncmp' is called without explicitly comparing result
+  // CHECK-FIXES: wcsncmp(W, L"a", 1) != 0)
+
+  if (wcscasecmp(W, L"a"))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'wcscasecmp' is called without explicitly comparing result
+  // CHECK-FIXES: wcscasecmp(W, L"a") != 0)
+
+  if (wcsicmp(W, L"a"))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'wcsicmp' is called without explicitly comparing result
+  // CHECK-FIXES: wcsicmp(W, L"a") != 0)
+
+  if (_wcsicmp(W, L"a"))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_wcsicmp' is called without explicitly comparing result
+  // CHECK-FIXES: _wcsicmp(W, L"a") != 0)
+
+  if (_wcsicmp_l(W, L"a", locale))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_wcsicmp_l' is called without explicitly comparing result
+  // CHECK-FIXES: _wcsicmp_l(W, L"a", locale) != 0)
+
+  if (wcsnicmp(W, L"a", 1))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'wcsnicmp' is called without explicitly comparing result
+  // CHECK-FIXES: wcsnicmp(W, L"a", 1) != 0)
+
+  if (_wcsnicmp(W, L"a", 1))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_wcsnicmp' is called without explicitly comparing result
+  // CHECK-FIXES: _wcsnicmp(W, L"a", 1) != 0)
+
+  if (_wcsnicmp_l(W, L"a", 1, locale))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_wcsnicmp_l' is called without explicitly comparing result
+  // CHECK-FIXES: _wcsnicmp_l(W, L"a", 1, locale) != 0)
+
+  if (_mbscmp(U, V))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_mbscmp' is called without explicitly comparing result
+  // CHECK-FIXES: _mbscmp(U, V) != 0)
+
+  if (_mbsncmp(U, V, 1))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_mbsncmp' is called without explicitly comparing result
+  // CHECK-FIXES: _mbsncmp(U, V, 1) != 0)
+
+  if (_mbsnbcmp(U, V, 1))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_mbsnbcmp' is called without explicitly comparing result
+  // CHECK-FIXES: _mbsnbcmp(U, V, 1) != 0)
+
+  if (_mbsnbicmp(U, V, 1))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_mbsnbicmp' is called without explicitly comparing result
+  // CHECK-FIXES: _mbsnbicmp(U, V, 1) != 0)
+
+  if (_mbsicmp(U, V))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_mbsicmp' is called without explicitly comparing result
+  // CHECK-FIXES: _mbsicmp(U, V) != 0)
+
+  if (_mbsnicmp(U, V, 1))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_mbsnicmp' is called without explicitly comparing result
+  // CHECK-FIXES: _mbsnicmp(U, V, 1) != 0)
+
+  if (_mbscmp_l(U, V, locale))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_mbscmp_l' is called without explicitly comparing result
+  // CHECK-FIXES: _mbscmp_l(U, V, locale) != 0)
+
+  if (_mbsncmp_l(U, V, 1, locale))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_mbsncmp_l' is called without explicitly comparing result
+  // CHECK-FIXES: _mbsncmp_l(U, V, 1, locale) != 0)
+
+  if (_mbsicmp_l(U, V, locale))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_mbsicmp_l' is called without explicitly comparing result
+  // CHECK-FIXES: _mbsicmp_l(U, V, locale) != 0)
+
+  if (_mbsnicmp_l(U, V, 1, locale))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_mbsnicmp_l' is called without explicitly comparing result
+  // CHECK-FIXES: _mbsnicmp_l(U, V, 1, locale) != 0)
+
+  if (_mbsnbcmp_l(U, V, 1, locale))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_mbsnbcmp_l' is called without explicitly comparing result
+  // CHECK-FIXES: _mbsnbcmp_l(U, V, 1, locale) != 0)
+
+  if (_mbsnbicmp_l(U, V, 1, locale))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function '_mbsnbicmp_l' is called without explicitly comparing result
+  // CHECK-FIXES: _mbsnbicmp_l(U, V, 1, locale) != 0)
+
+  return 1;
+}
+
+int strcmp_wrapper1(const char* a, const char* b) {
+  return strcmp(a, b);
+}
+
+int strcmp_wrapper2(const char* a, const char* b) {
+  return (a && b) ? strcmp(a, b) : 0;
+}
+
+#define macro_strncmp(s1, s2, n)                                              \
+  (__extension__ (__builtin_constant_p (n)                                    \
+                  && ((__builtin_constant_p (s1)                              \
+                       && strlen (s1) < ((size) (n)))                         \
+                      || (__builtin_constant_p (s2)                           \
+                          && strlen (s2) < ((size) (n))))                     \
+                  ? strcmp (s1, s2) : strncmp (s1, s2, n)))
+
+int strncmp_macro(const char* a, const char* b) {
+  if (macro_strncmp(a, b, 4))
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'strcmp' is called without explicitly comparing result
+
+  if (macro_strncmp(a, b, 4) == 2)
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'strcmp' is compared to a suspicious constant
+
+  if (macro_strncmp(a, b, 4) <= .0)
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: function 'strcmp' has suspicious implicit cast
+
+  if (macro_strncmp(a, b, 4) + 0)
+    return 0;
+  // CHECK-MESSAGES: [[@LINE-2]]:7: warning: results of function 'strcmp' used by operator '+'
+
+  return 1;
+}