From 2bb54fef69ab653943ceff0b428046a55c2df5dc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Marjam=C3=A4ki?= <daniel.marjamaki@gmail.com>
Date: Fri, 19 May 2017 14:34:59 +0200
Subject: [PATCH] ValueFlow: Test ErrorPath handling

---
 lib/valueflow.cpp      | 39 +++++++++++-----------------
 test/testvalueflow.cpp | 58 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 73 insertions(+), 24 deletions(-)

diff --git a/lib/valueflow.cpp b/lib/valueflow.cpp
index ac33e579e..829fed58d 100644
--- a/lib/valueflow.cpp
+++ b/lib/valueflow.cpp
@@ -2746,45 +2746,36 @@ static void valueFlowSubFunction(TokenList *tokenlist, ErrorLogger *errorLogger,
         if (!functionScope)
             continue;
 
-        unsigned int argnr = 0U;
-        for (const Token *argtok = tok->tokAt(2); argtok; argtok = argtok->nextArgument()) {
+        const std::vector<const Token *> &callArguments = getArguments(tok);
+        for (unsigned int argnr = 0U; argnr < callArguments.size(); ++argnr) {
+            const Token *argtok = callArguments[argnr];
             // Get function argument
-            const Variable * const arg = currentFunction->getArgumentVar(argnr++);
-            if (!arg)
+            const Variable * const argvar = currentFunction->getArgumentVar(argnr);
+            if (!argvar)
                 break;
 
-            std::list<ValueFlow::Value> argvalues;
-
             // passing value(s) to function
-            if (!argtok->values().empty() && Token::Match(argtok, "%name%|%num%|%str% [,)]"))
+            std::list<ValueFlow::Value> argvalues;
+            if (Token::Match(argtok, "%comp%|%oror%|&&|!") && !argtok->hasKnownIntValue()) {
+                argvalues.push_back(ValueFlow::Value(0));
+                argvalues.push_back(ValueFlow::Value(1));
+            } else {
                 argvalues = argtok->values();
-            else {
-                // bool operator => values 1/0 are passed to function..
-                const Token *op = argtok;
-                while (op && op->astParent() && !Token::Match(op->astParent(), "[(,]"))
-                    op = op->astParent();
-                if (Token::Match(op, "%comp%|%oror%|&&|!")) {
-                    argvalues.clear();
-                    argvalues.push_back(ValueFlow::Value(0));
-                    argvalues.push_back(ValueFlow::Value(1));
-                } else if (Token::Match(op, "%cop%") && !op->values().empty()) {
-                    argvalues = op->values();
-                } else {
-                    // possible values are unknown..
-                    continue;
-                }
             }
 
+            if (argvalues.empty())
+                continue;
+
             // Error path..
             for (std::list<ValueFlow::Value>::iterator it = argvalues.begin(); it != argvalues.end(); ++it)
-                it->errorPath.push_back(ErrorPathItem(argtok, "function call argument"));
+                it->errorPath.push_back(ErrorPathItem(argtok, "Function argument, integer value " + MathLib::toString(it->intvalue)));
 
             // passed values are not "known"..
             for (std::list<ValueFlow::Value>::iterator it = argvalues.begin(); it != argvalues.end(); ++it) {
                 it->changeKnownToPossible();
             }
 
-            valueFlowInjectParameter(tokenlist, errorLogger, settings, arg, functionScope, argvalues);
+            valueFlowInjectParameter(tokenlist, errorLogger, settings, argvar, functionScope, argvalues);
         }
     }
 }
diff --git a/test/testvalueflow.cpp b/test/testvalueflow.cpp
index 90d97bc17..8ce3323cd 100644
--- a/test/testvalueflow.cpp
+++ b/test/testvalueflow.cpp
@@ -53,6 +53,8 @@ private:
 
         TEST_CASE(valueFlowCalculations);
 
+        TEST_CASE(valueFlowErrorPath);
+
         TEST_CASE(valueFlowBeforeCondition);
         TEST_CASE(valueFlowBeforeConditionAndAndOrOrGuard);
         TEST_CASE(valueFlowBeforeConditionAssignIncDec);
@@ -108,6 +110,30 @@ private:
         return false;
     }
 
+    std::string getErrorPathForX(const char code[], unsigned int linenr) {
+        // Tokenize..
+        Tokenizer tokenizer(&settings, this);
+        std::istringstream istr(code);
+        tokenizer.tokenize(istr, "test.cpp");
+
+        for (const Token *tok = tokenizer.tokens(); tok; tok = tok->next()) {
+            if (tok->str() != "x" || tok->linenr() != linenr)
+                continue;
+
+            std::ostringstream ostr;
+            std::list<ValueFlow::Value>::const_iterator it;
+            for (it = tok->values().begin(); it != tok->values().end(); ++it) {
+                for (ValueFlow::Value::ErrorPath::const_iterator ep = it->errorPath.begin(); ep != it->errorPath.end(); ++ep) {
+                    const Token *eptok = ep->first;
+                    const std::string &msg = ep->second;
+                    ostr << eptok->linenr() << ',' << msg << '\n';
+                }
+            }
+            return ostr.str();
+        }
+
+        return "";
+    }
 
     bool testValueOfX(const char code[], unsigned int linenr, const char value[]) {
         // Tokenize..
@@ -562,6 +588,38 @@ private:
         ASSERT_EQUALS(1, values.front().intvalue);
     }
 
+    void valueFlowErrorPath() {
+        const char *code;
+
+        code = "void f() {\n"
+               "  int x = 53;\n"
+               "  a = x;\n"
+               "}\n";
+        ASSERT_EQUALS("2,Assignment, integer value 53\n",
+                      getErrorPathForX(code, 3U));
+
+        code = "void f(int y) {\n"
+               "  int x = y;\n"
+               "  a = x;\n"
+               "  y += 12;\n"
+               "  if (y == 32) {}"
+               "}\n";
+        ASSERT_EQUALS("5,Condition 'y==32'\n"
+                      "2,Assignment, integer value 20\n",
+                      getErrorPathForX(code, 3U));
+
+        code = "void f1(int x) {\n"
+               "  a = x;\n"
+               "}\n"
+               "void f2() {\n"
+               "  int x = 3;\n"
+               "  f1(x+1);\n"
+               "}\n";
+        ASSERT_EQUALS("5,Assignment, integer value 3\n"
+                      "6,Function argument, integer value 4\n",
+                      getErrorPathForX(code, 2U));
+    }
+
     void valueFlowBeforeCondition() {
         const char *code;