added acos() check to ticket #1513; added testcases for MathLib::toDoubleNumber(), now double conversion of zeros is handled correctly; changed assertEquals() function of testsuite parameters from unsigned int to double. This is needed to avoid overflow of unsigned int by comparing negative floating point values.

lib/checkother.cpp

@@ -30,6 +30,7 @@
 #include <cstring>
 #include <cctype>
 #include <memory>
+#include <cmath> // fabs()
 //---------------------------------------------------------------------------
 
 // Register this check class (by creating a static instance of it)
@@ -2472,6 +2473,12 @@ void CheckOther::checkMathFunctions()
                  MathLib::toLongNumber(tok->tokAt(2)->str()) <= 0)
         {
             mathfunctionCallError(tok);
+        }
+		// acos( x )  x is defined for intervall [-1,+1], but not beyound
+		else if(Token::Match(tok, "acos ( %num% )") &&
+				fabs(MathLib::toDoubleNumber(tok->tokAt(2)->str())) > 1.0)
+        {
+            mathfunctionCallError(tok);
         }
     }
 }

lib/mathlib.cpp

@@ -55,6 +55,11 @@ double MathLib::toDoubleNumber(const std::string &str)
     {
         return std::strtoul(str.c_str(), '\0', 16);
     }
+	// nullcheck
+	else if (str == "-0" || str == "-0.0" ||  str == "-0."
+         ||  str == "+0" || str == "+0.0" ||  str == "+0.")
+        	return 0.0;
+	// otherwise, convert to double
     std::istringstream istr(str.c_str());
     double ret;
     istr >> ret;

test/testmathlib.cpp

@@ -115,6 +115,27 @@ private:
         ASSERT_EQUALS(-1	, MathLib::toLongNumber("-10.E-1"));
         ASSERT_EQUALS(100	, MathLib::toLongNumber("+10.0E+1"));
         ASSERT_EQUALS(-1	, MathLib::toLongNumber("-10.0E-1"));
+
+		// -----------------
+		// to double number:
+		// -----------------
+        ASSERT_EQUALS(10.0	, MathLib::toDoubleNumber("10"));
+        ASSERT_EQUALS(1000.0, MathLib::toDoubleNumber("10E+2"));
+        ASSERT_EQUALS(100.0 , MathLib::toDoubleNumber("1.0E+2"));
+        ASSERT_EQUALS(-100.0, MathLib::toDoubleNumber("-1.0E+2"));
+        ASSERT_EQUALS(-1e+10, MathLib::toDoubleNumber("-1.0E+10"));
+        ASSERT_EQUALS(100.0 , MathLib::toDoubleNumber("+1.0E+2"));
+        ASSERT_EQUALS(1e+10 , MathLib::toDoubleNumber("+1.0E+10"));
+        ASSERT_EQUALS(100.0 , MathLib::toDoubleNumber("1.0E+2"));
+        ASSERT_EQUALS(1e+10 , MathLib::toDoubleNumber("1.0E+10"));
+        ASSERT_EQUALS(0.0   , MathLib::toDoubleNumber("0"));
+        ASSERT_EQUALS(0.0   , MathLib::toDoubleNumber("-0"));
+        ASSERT_EQUALS(0.0   , MathLib::toDoubleNumber("+0"));
+        ASSERT_EQUALS(0.0   , MathLib::toDoubleNumber("-0."));
+        ASSERT_EQUALS(0.0   , MathLib::toDoubleNumber("+0."));
+        ASSERT_EQUALS(0.0   , MathLib::toDoubleNumber("-0.0"));
+        ASSERT_EQUALS(0.0   , MathLib::toDoubleNumber("+0.0"));
+		
     }
 
     void isint()

test/testother.cpp

@@ -2169,6 +2169,7 @@ private:
 
     void mathfunctionCall1()
     {
+		// log|log10
         check("void foo()\n"
               "{\n"
               "    std::cout <<  log(-2) << std::endl;\n"
@@ -2228,9 +2229,42 @@ private:
               "    std::cout <<  log(1E-3) << std::endl;\n"
               "}");
         TODO_ASSERT_EQUALS("", errout.str());
+
+		// acos
+        check("void foo()\n"
+              "{\n"
+              "    std::cout <<  acos(1) 		<< std::endl;\n"
+              "    std::cout <<  acos(-1) 		<< std::endl;\n"
+              "    std::cout <<  acos(0.1)  	<< std::endl;\n"
+              "    std::cout <<  acos(0.0001) 	<< std::endl;\n"
+              "    std::cout <<  acos(0.01) 	<< std::endl;\n"
+              "    std::cout <<  acos(1.0E-1) 	<< std::endl;\n"
+              "    std::cout <<  acos(-1.0E-1)  << std::endl;\n"
+              "    std::cout <<  acos(+1.0E-1)  << std::endl;\n"
+              "    std::cout <<  acos(0.1E-1)   << std::endl;\n"
+              "    std::cout <<  acos(+0.1E-1)  << std::endl;\n"
+              "    std::cout <<  acos(-0.1E-1)  << std::endl;\n"
+              "}");
+        ASSERT_EQUALS("", errout.str());
+
+        check("void foo()\n"
+              "{\n"
+              "    std::cout <<  acos(1.1) << std::endl;\n"
+              "}");
+        ASSERT_EQUALS("[test.cpp:3]: (error) Passing value 1.1 to acos() leads to undefined result\n", errout.str());
+
+        check("void foo()\n"
+              "{\n"
+              "    std::cout <<  acos(-1.1) << std::endl;\n"
+              "}");
+        ASSERT_EQUALS("[test.cpp:3]: (error) Passing value -1.1 to acos() leads to undefined result\n", errout.str());
+
+        check("void foo()\n"
+              "{\n"
+              "    std::cout <<  acos(-110) << std::endl;\n"
+              "}");
+        ASSERT_EQUALS("[test.cpp:3]: (error) Passing value -110 to acos() leads to undefined result\n", errout.str());
     }
-
-
 };
 
 REGISTER_TEST(TestOther)

test/testsuite.cpp

@@ -118,7 +118,7 @@ void TestFixture::assertEquals(const char *filename, int linenr, const std::stri
     }
 }
 
-void TestFixture::assertEquals(const char *filename, int linenr, unsigned int expected, unsigned int actual)
+void TestFixture::assertEquals(const char *filename, int linenr, double expected, double actual)
 {
     std::ostringstream ostr1;
     ostr1 << expected;

test/testsuite.h

@@ -42,7 +42,11 @@ protected:
     bool runTest(const char testname[]);
 
     void assertEquals(const char *filename, int linenr, const std::string &expected, const std::string &actual);
-    void assertEquals(const char *filename, int linenr, unsigned int expected, unsigned int actual);
+
+	// the vars expected and actual need to be of type double, in order to avoid overflow of unsigned int
+	// e.g: ASSERT_EQUALS(-100.0, MathLib::toDoubleNumber("-1.0E+2")); whould not work without this.
+	void assertEquals(const char *filename, int linenr, double expected, double actual);
+
     void todoAssertEquals(const char *filename, int linenr, const std::string &expected, const std::string &actual);
     void todoAssertEquals(const char *filename, int linenr, unsigned int expected, unsigned int actual);
     void assertThrowFail(const char *filename, int linenr);