From 9ab4f9976d7b8c7e80f154b9d74105753ff01652 Mon Sep 17 00:00:00 2001
From: chrchr-github <78114321+chrchr-github@users.noreply.github.com>
Date: Mon, 29 Aug 2022 12:25:10 +0200
Subject: [PATCH] Fix #10426 FN (style) Condition 's.empty()' is always false
 (#4414)

* Fix #10426 FN (style) Condition 's.empty()' is always false

* Fix test
---
 lib/checkcondition.cpp |  2 +-
 test/cfg/qt.cpp        |  2 +-
 test/testcondition.cpp | 12 ++++++++++++
 3 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/lib/checkcondition.cpp b/lib/checkcondition.cpp
index 97e378cfe..eaf0ac338 100644
--- a/lib/checkcondition.cpp
+++ b/lib/checkcondition.cpp
@@ -1516,7 +1516,7 @@ void CheckCondition::alwaysTrueFalse()
                 tok->astParent() && Token::Match(tok->astTop()->astOperand1(), "if|while") && !tok->astTop()->astOperand1()->isConstexpr() &&
                 (Token::Match(tok->astParent(), "%oror%|&&") || Token::Match(tok->astParent()->astOperand1(), "if|while"));
             const bool constValExpr = tok->isNumber() && Token::Match(tok->astParent(),"%oror%|&&|?"); // just one number in boolean expression
-            const bool compExpr = Token::Match(tok, "%comp%|!"); // a compare expression
+            const bool compExpr = Token::Match(tok, "%comp%|!|("); // a compare expression
             const bool ternaryExpression = Token::simpleMatch(tok->astParent(), "?");
             const bool returnExpression = Token::simpleMatch(tok->astTop(), "return") && (tok->isComparisonOp() || Token::Match(tok, "&&|%oror%"));
 
diff --git a/test/cfg/qt.cpp b/test/cfg/qt.cpp
index 736fbf2ee..c793e48fc 100644
--- a/test/cfg/qt.cpp
+++ b/test/cfg/qt.cpp
@@ -32,7 +32,7 @@ void QString1(QString s)
 int QString2()
 {
     QString s;
-    // FIXME cppcheck-suppress reademptycontainer
+    // cppcheck-suppress knownConditionTrueFalse
     return s.size();
 }
 
diff --git a/test/testcondition.cpp b/test/testcondition.cpp
index df87884af..f85fdebab 100644
--- a/test/testcondition.cpp
+++ b/test/testcondition.cpp
@@ -4305,6 +4305,18 @@ private:
               "    else if (x < 1) {}\n"
               "}\n");
         ASSERT_EQUALS("", errout.str());
+
+        // #10426
+        check("void f() {\n"
+              "    std::string s;\n"
+              "    for (; !s.empty();) {}\n"
+              "    for (; s.empty();) {}\n"
+              "    if (s.empty()) {}\n"
+              "}\n");
+        ASSERT_EQUALS("[test.cpp:3]: (style) Condition '!s.empty()' is always false\n"
+                      "[test.cpp:4]: (style) Condition 's.empty()' is always true\n"
+                      "[test.cpp:5]: (style) Condition 's.empty()' is always true\n",
+                      errout.str());
     }
 
     void alwaysTrueSymbolic()