/*

* Cppcheck - A tool for static C/C++ code analysis

* Copyright (C) 2007-2015 Cppcheck team.

*

* This program is free software: you can redistribute it and/or modify

* it under the terms of the GNU General Public License as published by

* the Free Software Foundation, either version 3 of the License, or

* (at your option) any later version.

*

* This program is distributed in the hope that it will be useful,

* but WITHOUT ANY WARRANTY; without even the implied warranty of

* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

* GNU General Public License for more details.

*

* You should have received a copy of the GNU General Public License

* along with this program. If not, see <http://www.gnu.org/licenses/>.

*/

#include "tokenize.h"

#include "checkcondition.h"

#include "testsuite.h"

#include <tinyxml2.h>

class TestCondition : public TestFixture {

public:

TestCondition() : TestFixture("TestCondition") {

}

private:

Settings settings0;

Settings settings1;

void run() {

settings0.addEnabled("style");

settings0.addEnabled("warning");

const char cfg[] = "<?xml version=\"1.0\"?>\n"

"<def>\n"

" <function name=\"bar\"> <pure/> </function>\n"

"</def>";

tinyxml2::XMLDocument xmldoc;

xmldoc.Parse(cfg, sizeof(cfg));

settings1.addEnabled("style");

settings1.addEnabled("warning");

settings1.library.load(xmldoc);

TEST_CASE(assignAndCompare); // assignment and comparison don't match

TEST_CASE(mismatchingBitAnd); // overlapping bitmasks

TEST_CASE(compare); // mismatching LHS/RHS in comparison

TEST_CASE(multicompare); // mismatching comparisons

TEST_CASE(duplicateIf); // duplicate conditions in if and else-if

TEST_CASE(checkBadBitmaskCheck);

TEST_CASE(incorrectLogicOperator1);

TEST_CASE(incorrectLogicOperator2);

TEST_CASE(incorrectLogicOperator3);

TEST_CASE(incorrectLogicOperator4);

TEST_CASE(incorrectLogicOperator5); // complex expressions

TEST_CASE(incorrectLogicOperator6); // char literals

TEST_CASE(incorrectLogicOperator7); // opposite expressions: (expr || !expr)

TEST_CASE(incorrectLogicOperator8); // !

TEST_CASE(incorrectLogicOperator9);

TEST_CASE(secondAlwaysTrueFalseWhenFirstTrueError);

TEST_CASE(incorrectLogicOp_condSwapping);

TEST_CASE(testBug5895);

TEST_CASE(testBug5309);

TEST_CASE(modulo);

TEST_CASE(oppositeInnerCondition);

TEST_CASE(clarifyCondition1); // if (a = b() < 0)

TEST_CASE(clarifyCondition2); // if (a & b == c)

TEST_CASE(clarifyCondition3); // if (! a & b)

TEST_CASE(clarifyCondition4); // ticket #3110

TEST_CASE(clarifyCondition5); // #3609 CWinTraits<WS_CHILD|WS_VISIBLE>..

TEST_CASE(clarifyCondition6); // #3818

TEST_CASE(alwaysTrue);

TEST_CASE(checkInvalidTestForOverflow);

}

void check(const char code[], const char* filename = "test.cpp") {

// Clear the error buffer..

errout.str("");

CheckCondition checkCondition;

// Tokenize..

Tokenizer tokenizer(&settings0, this);

std::istringstream istr(code);

tokenizer.tokenize(istr, filename);

checkCondition.runChecks(&tokenizer, &settings0, this);

tokenizer.simplifyTokenList2();

checkCondition.runSimplifiedChecks(&tokenizer, &settings0, this);

}

void assignAndCompare() {

// &

check("void foo(int x)\n"

"{\n"

" int y = x & 4;\n"

" if (y == 3);\n"

"}");

ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4]: (style) Mismatching assignment and comparison, comparison 'y==3' is always false.\n", errout.str());

check("void foo(int x)\n"

"{\n"

" int y = x & 4;\n"

" if (y != 3);\n"

"}");

ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4]: (style) Mismatching assignment and comparison, comparison 'y!=3' is always true.\n", errout.str());

// |

check("void foo(int x) {\n"

" int y = x | 0x14;\n"

" if (y == 0x710);\n"

"}");

ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Mismatching assignment and comparison, comparison 'y==1808' is always false.\n", errout.str());

check("void foo(int x) {\n"

" int y = x | 0x14;\n"

" if (y == 0x71f);\n"

"}");

ASSERT_EQUALS("", errout.str());

// various simple assignments

check("void foo(int x) {\n"

" int y = (x+1) | 1;\n"

" if (y == 2);\n"

"}");

ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Mismatching assignment and comparison, comparison 'y==2' is always false.\n", errout.str());

check("void foo() {\n"

" int y = 1 | x();\n"

" if (y == 2);\n"

"}");

ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Mismatching assignment and comparison, comparison 'y==2' is always false.\n", errout.str());

// multiple conditions

check("void foo(int x) {\n"

" int y = x & 4;\n"

" if ((y == 3) && (z == 1));\n"

"}");

ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Mismatching assignment and comparison, comparison 'y==3' is always false.\n", errout.str());

check("void foo(int x) {\n"

" int y = x & 4;\n"

" if ((x==123) || ((y == 3) && (z == 1)));\n"

"}");

ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Mismatching assignment and comparison, comparison 'y==3' is always false.\n", errout.str());

check("void f(int x) {\n"

" int y = x & 7;\n"

" if (setvalue(&y) && y != 8);\n"

"}");

ASSERT_EQUALS("", errout.str());

// recursive checking into scopes

check("void f(int x) {\n"

" int y = x & 7;\n"

" if (z) y=0;\n"

" else { if (y==8); }\n" // always false

"}");

ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:4]: (style) Mismatching assignment and comparison, comparison 'y==8' is always false.\n", errout.str());

// while

check("void f(int x) {\n"

" int y = x & 7;\n"

" while (y==8);\n" // local variable => always false

"}");

ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Mismatching assignment and comparison, comparison 'y==8' is always false.\n", errout.str());

check("void f(int x) {\n"

" extern int y; y = x & 7;\n"

" while (y==8);\n" // non-local variable => no error

"}");

ASSERT_EQUALS("", errout.str());

check("void f(int x) {\n"

" int a = 100;\n"

" while (x) {\n"

" int y = 16 | a;\n"

" while (y != 0) y--;\n"

" }\n"

"}");

ASSERT_EQUALS("", errout.str());

// calling function

check("void f(int x) {\n"

" int y = x & 7;\n"

" do_something();\n"

" if (y==8);\n" // local variable => always false

"}");

ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:4]: (style) Mismatching assignment and comparison, comparison 'y==8' is always false.\n", errout.str());

check("void f(int x) {\n"

" int y = x & 7;\n"

" do_something(&y);\n" // passing variable => no error

" if (y==8);\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void do_something(int);\n"

"void f(int x) {\n"

" int y = x & 7;\n"

" do_something(y);\n"

" if (y==8);\n"

"}");

ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:5]: (style) Mismatching assignment and comparison, comparison 'y==8' is always false.\n", errout.str());

check("void f(int x) {\n"

" extern int y; y = x & 7;\n"

" do_something();\n"

" if (y==8);\n" // non-local variable => no error

"}");

ASSERT_EQUALS("", errout.str());

// #4434 : false positive: ?:

check("void f(int x) {\n"

" x = x & 1;\n"

" x = x & 1 ? 1 : -1;\n"

" if(x != -1) { }\n"

"}");

ASSERT_EQUALS("", errout.str());

// #4735

check("void f() {\n"

" int x = *(char*)&0x12345678;\n"

" if (x==18) { }\n"

"}");

ASSERT_EQUALS("", errout.str());

// bailout: no variable info

check("void foo(int x) {\n"

" y = 2 | x;\n" // y not declared => no error

" if(y == 1) {}\n"

"}");

ASSERT_EQUALS("", errout.str());

// bailout: negative number

check("void foo(int x) {\n"

" int y = -2 | x;\n" // negative number => no error

" if (y==1) {}\n"

"}");

ASSERT_EQUALS("", errout.str());

// bailout: pass variable to function

check("void foo(int x) {\n"

" int y = 2 | x;\n"

" bar(&y);\n" // pass variable to function => no error

" if (y==1) {}\n"

"}");

ASSERT_EQUALS("", errout.str());

// no crash on unary operator& (#5643)

check("SdrObject* ApplyGraphicToObject() {\n"

" if (&rHitObject) {}\n"

" else if (rHitObject.IsClosedObj() && !&rHitObject) { }\n"

"}");

ASSERT_EQUALS("", errout.str());

// #5695: increment

check("void f(int a0, int n) {\n"

" int c = a0 & 3;\n"

" for (int a = 0; a < n; a++) {\n"

" c++;\n"

" if (c == 4)\n"

" c = 0;\n"

" }\n"

"}\n");

ASSERT_EQUALS("", errout.str());

check("void f(int a) {\n" // #6662

" int x = a & 1;\n"

" while (x <= 4) {\n"

" if (x != 5) {}\n"

" }\n"

"}\n");

ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:4]: (style) Mismatching assignment and comparison, comparison 'x!=5' is always true.\n", errout.str());

check("void f(int a) {\n" // #6662

" int x = a & 1;\n"

" while ((x += 4) < 10) {\n"

" if (x != 5) {}\n"

" }\n"

"}\n");

ASSERT_EQUALS("", errout.str());

}

void mismatchingBitAnd() {

check("void f(int a) {\n"

" int b = a & 0xf0;\n"

" b &= 1;\n"

"}");

ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Mismatching bitmasks. Result is always 0 (X = Y & 0xf0; Z = X & 0x1; => Z=0).\n", errout.str());

check("void f(int a) {\n"

" int b = a & 0xf0;\n"

" int c = b & 1;\n"

"}");

ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Mismatching bitmasks. Result is always 0 (X = Y & 0xf0; Z = X & 0x1; => Z=0).\n", errout.str());

check("void f(int a) {\n"

" int b = a;"

" switch (x) {\n"

" case 1: b &= 1; break;\n"

" case 2: b &= 2; break;\n"

" };\n"

"}");

ASSERT_EQUALS("", errout.str());

}

void compare() {

check("void foo(int x)\n"

"{\n"

" if ((x & 4) == 3);\n"

"}");

ASSERT_EQUALS("[test.cpp:3]: (style) Expression '(X & 0x4) == 0x3' is always false.\n", errout.str());

check("void foo(int x)\n"

"{\n"

" if ((x | 4) == 3);\n"

"}");

ASSERT_EQUALS("[test.cpp:3]: (style) Expression '(X | 0x4) == 0x3' is always false.\n", errout.str());

check("void foo(int x)\n"

"{\n"

" if ((x | 4) != 3);\n"

"}");

ASSERT_EQUALS("[test.cpp:3]: (style) Expression '(X | 0x4) != 0x3' is always true.\n", errout.str());

check("void foo(int x)\n"

"{\n"

" if ((x & y & 4 & z ) == 3);\n"

"}");

ASSERT_EQUALS("[test.cpp:3]: (style) Expression '(X & 0x4) == 0x3' is always false.\n", errout.str());

}

void multicompare() {

check("void foo(int x)\n"

"{\n"

" if (x & 7);\n"

" else { if (x == 1); }\n"

"}");

ASSERT_EQUALS("[test.cpp:4]: (style) Expression is always false because 'else if' condition matches previous condition at line 3.\n", errout.str());

check("void foo(int x)\n"

"{\n"

" if (x & 7);\n"

" else { if (x & 1); }\n"

"}");

ASSERT_EQUALS("[test.cpp:4]: (style) Expression is always false because 'else if' condition matches previous condition at line 3.\n", errout.str());

check("extern int bar() __attribute__((pure));\n"

"void foo(int x)\n"

"{\n"

" if ( bar() >1 && b) {}\n"

" else if (bar() >1 && b) {}\n"

"}");

ASSERT_EQUALS("[test.cpp:5]: (style) Expression is always false because 'else if' condition matches previous condition at line 4.\n", errout.str());

checkPureFunction("extern int bar();\n"

"void foo(int x)\n"

"{\n"

" if ( bar() >1 && b) {}\n"

" else if (bar() >1 && b) {}\n"

"}");

ASSERT_EQUALS("[test.cpp:5]: (style) Expression is always false because 'else if' condition matches previous condition at line 4.\n", errout.str());

}

void checkPureFunction(const char code[]) {

// Clear the error buffer..

errout.str("");

// Tokenize..

Tokenizer tokenizer(&settings1, this);

std::istringstream istr(code);

tokenizer.tokenize(istr, "test.cpp");

CheckCondition checkCondition;

checkCondition.runChecks(&tokenizer, &settings1, this);

tokenizer.simplifyTokenList2();

checkCondition.runSimplifiedChecks(&tokenizer, &settings1, this);

}

void duplicateIf() {

check("void f(int a, int &b) {\n"

" if (a) { b = 1; }\n"

" else { if (a) { b = 2; } }\n"

"}");

ASSERT_EQUALS("[test.cpp:3]: (style) Expression is always false because 'else if' condition matches previous condition at line 2.\n", errout.str());

check("void f(int a, int &b) {\n"

" if (a) { b = 1; }\n"

" else { if (a) { b = 2; } }\n"

"}");

ASSERT_EQUALS("[test.cpp:3]: (style) Expression is always false because 'else if' condition matches previous condition at line 2.\n", errout.str());

check("void f(int a, int &b) {\n"

" if (a == 1) { b = 1; }\n"

" else { if (a == 2) { b = 2; }\n"

" else { if (a == 1) { b = 3; } } }\n"

"}");

ASSERT_EQUALS("[test.cpp:4]: (style) Expression is always false because 'else if' condition matches previous condition at line 2.\n", errout.str());

check("void f(int a, int &b) {\n"

" if (a == 1) { b = 1; }\n"

" else { if (a == 2) { b = 2; }\n"

" else { if (a == 2) { b = 3; } } }\n"

"}");

ASSERT_EQUALS("[test.cpp:4]: (style) Expression is always false because 'else if' condition matches previous condition at line 3.\n", errout.str());

check("void f(int a, int &b) {\n"

" if (a++) { b = 1; }\n"

" else { if (a++) { b = 2; }\n"

" else { if (a++) { b = 3; } } }\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void f(int a, int &b) {\n"

" if (!strtok(NULL, \" \")) { b = 1; }\n"

" else { if (!strtok(NULL, \" \")) { b = 2; } }\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void f(int a, int &b) {\n"

" x = x / 2;\n"

" if (x < 100) { b = 1; }\n"

" else { x = x / 2; if (x < 100) { b = 2; } }\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void f(int i) {\n"

" if(i == 0x02e2000000 || i == 0xa0c6000000)\n"

" foo(i);\n"

"}");

ASSERT_EQUALS("", errout.str());

// ticket 3689 ( avoid false positive )

check("int fitInt(long long int nValue){\n"

" if( nValue < 0x7fffffffLL )\n"

" {\n"

" return 32;\n"

" }\n"

" if( nValue < 0x7fffffffffffLL )\n"

" {\n"

" return 48;\n"

" }\n"

" else {\n"

" if( nValue < 0x7fffffffffffffffLL )\n"

" {\n"

" return 64;\n"

" } else\n"

" {\n"

" return -1;\n"

" }\n"

" }\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void f(WIDGET *widget) {\n"

" if (dynamic_cast<BUTTON*>(widget)){}\n"

" else if (dynamic_cast<LABEL*>(widget)){}\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void f(int x) {\n" // #6482

" if (x & 1) {}\n"

" else if (x == 0) {}\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void f(int x) {\n"

" if (x & 15) {}\n"

" else if (x == 40) {}\n"

"}");

ASSERT_EQUALS("[test.cpp:3]: (style) Expression is always false because 'else if' condition matches previous condition at line 2.\n", errout.str());

}

void checkBadBitmaskCheck() {

check("bool f(int x) {\n"

" bool b = x | 0x02;\n"

" return b;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());

check("bool f(int x) {\n"

" bool b = 0x02 | x;\n"

" return b;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());

check("int f(int x) {\n"

" int b = x | 0x02;\n"

" return b;\n"

"}");

ASSERT_EQUALS("", errout.str());

check("bool f(int x) {\n"

" bool b = x & 0x02;\n"

" return b;\n"

"}");

ASSERT_EQUALS("", errout.str());

check("bool f(int x) {\n"

" if(x | 0x02)\n"

" return b;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());

check("bool f(int x) {\n"

" int y = 0x1;\n"

" if(b) y = 0;\n"

" if(x | y)\n"

" return b;\n"

"}");

ASSERT_EQUALS("", errout.str());

check("bool f(int x) {\n"

" foo(a && (x | 0x02));\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());

check("int f(int x) {\n"

" return (x | 0x02) ? 0 : 5;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());

check("int f(int x) {\n"

" return x ? (x | 0x02) : 5;\n"

"}");

ASSERT_EQUALS("", errout.str());

check("bool f(int x) {\n"

" return x | 0x02;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());

check("bool f(int x) {\n"

" if (x) {\n"

" return x | 0x02;\n"

" }\n"

" return 0;\n"

"}");

ASSERT_EQUALS("[test.cpp:3]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());

check("const bool f(int x) {\n"

" return x | 0x02;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());

check("struct F {\n"

" static const bool f(int x) {\n"

" return x | 0x02;\n"

" }\n"

"};");

ASSERT_EQUALS("[test.cpp:3]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());

check("struct F {\n"

" typedef bool b_t;\n"

"};\n"

"F::b_t f(int x) {\n"

" return x | 0x02;\n"

"}");

ASSERT_EQUALS("[test.cpp:5]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());

check("int f(int x) {\n"

" return x | 0x02;\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void create_rop_masks_4( rop_mask_bits *bits) {\n"

"DWORD mask_offset;\n"

"BYTE *and_bits = bits->and;\n"

"rop_mask *rop_mask;\n"

"and_bits[mask_offset] |= (rop_mask->and & 0x0f);\n"

"}");

ASSERT_EQUALS("", errout.str());

}

void incorrectLogicOperator1() {

check("void f(int x) {\n"

" if ((x != 1) || (x != 3))\n"

" a++;\n"

"}\n"

);

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x != 1 || x != 3.\n", errout.str());

check("void f(int x) {\n"

" if (1 != x || 3 != x)\n"

" a++;\n"

"}\n"

);

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x != 1 || x != 3.\n", errout.str());

check("void f(int x) {\n"

" if (x<0 && !x) {}\n"

"}\n");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x < 0 && !x.\n", errout.str());

check("void f(int x) {\n"

" if (x==0 && x) {}\n"

"}\n");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x == 0 && x.\n", errout.str());

check("void f(int x) {\n" // ast..

" if (y == 1 && x == 1 && x == 7) { }\n"

"}\n");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x == 1 && x == 7.\n", errout.str());

check("void f(int x, int y) {\n"

" if (x != 1 || y != 1)\n"

" a++;\n"

"}\n"

);

ASSERT_EQUALS("", errout.str());

check("void f(int x, int y) {\n"

" if ((y == 1) && (x != 1) || (x != 3))\n"

" a++;\n"

"}\n"

);

ASSERT_EQUALS("", errout.str());

check("void f(int x, int y) {\n"

" if ((x != 1) || (x != 3) && (y == 1))\n"

" a++;\n"

"}\n"

);

ASSERT_EQUALS("", errout.str());

check("void f(int x) {\n"

" if ((x != 1) && (x != 3))\n"

" a++;\n"

"}\n"

);

ASSERT_EQUALS("", errout.str());

check("void f(int x) {\n"

" if ((x == 1) || (x == 3))\n"

" a++;\n"

"}\n"

);

ASSERT_EQUALS("", errout.str());

check("void f(int x, int y) {\n"

" if ((x != 1) || (y != 3))\n"

" a++;\n"

"}\n"

);

ASSERT_EQUALS("", errout.str());

check("void f(int x, int y) {\n"

" if ((x != hotdog) || (y != hotdog))\n"

" a++;\n"

"}\n"

);

ASSERT_EQUALS("", errout.str());

check("void f(int x, int y) {\n"

" if ((x != 5) || (y != 5))\n"

" a++;\n"

"}\n"

);

ASSERT_EQUALS("", errout.str());

check("void f(int x) {\n"

" if ((x != 5) || (x != 6))\n"

" a++;\n"

"}\n"

);

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x != 5 || x != 6.\n", errout.str());

check("void f(unsigned int a, unsigned int b, unsigned int c) {\n"

" if((a != b) || (c != b) || (c != a))\n"

" {\n"

" return true;\n"

" }\n"

" return false;\n"

"}\n"

);

ASSERT_EQUALS("", errout.str());

}

void incorrectLogicOperator2() {

check("void f(float x) {\n"

" if ((x == 1) && (x == 1.0))\n"

" a++;\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void f(int x) {\n"

" if ((x == 1) && (x == 0x00000001))\n"

" a++;\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void f(int x) {\n"

" if (x == 1 && x == 3)\n"

" a++;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x == 1 && x == 3.\n", errout.str());

check("void f(int x) {\n"

" if (x == 1.0 && x == 3.0)\n"

" a++;\n"

"}");

ASSERT_EQUALS("", errout.str()); // float comparisons with == and != are not checked right now - such comparison is a bad idea

check("void f(float x) {\n"

" if (x == 1 && x == 1.0)\n"

" a++;\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void bar(float f) {\n" // #5246

" if ((f > 0) && (f < 1)) {}\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void f(int x) {\n"

" if (x < 1 && x > 1)\n"

" a++;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x < 1 && x > 1.\n", errout.str());

check("void f(int x) {\n"

" if (x < 1.0 && x > 1.0)\n"

" a++;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x < 1.0 && x > 1.0.\n", errout.str());

check("void f(int x) {\n"

" if (x < 1 && x > 1.0)\n"

" a++;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x < 1 && x > 1.0.\n", errout.str());

check("void f(int x) {\n"

" if (x >= 1.0 && x <= 1.001)\n"

" a++;\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void f(int x) {\n"

" if (x < 1 && x > 3)\n"

" a++;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x < 1 && x > 3.\n", errout.str());

check("void f(float x) {\n"

" if (x < 1.0 && x > 3.0)\n"

" a++;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x < 1.0 && x > 3.0.\n", errout.str());

check("void f(int x) {\n"

" if (1 > x && 3 < x)\n"

" a++;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x < 1 && x > 3.\n", errout.str());

check("void f(int x) {\n"

" if (x < 3 && x > 1)\n"

" a++;\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void f(int x) {\n"

" if (x > 3 || x < 10)\n"

" a++;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x > 3 || x < 10.\n", errout.str());

check("void f(int x) {\n"

" if (x >= 3 || x <= 10)\n"

" a++;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x >= 3 || x <= 10.\n", errout.str());

check("void f(int x) {\n"

" if (x >= 3 || x < 10)\n"

" a++;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x >= 3 || x < 10.\n", errout.str());

check("void f(int x) {\n"

" if (x > 3 || x <= 10)\n"

" a++;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x > 3 || x <= 10.\n", errout.str());

check("void f(int x) {\n"

" if (x > 3 || x < 3)\n"

" a++;\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void f(int x) {\n"

" if (x >= 3 || x <= 3)\n"

" a++;\n"

"}"

);

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x >= 3 || x <= 3.\n", errout.str());

check("void f(int x) {\n"

" if (x >= 3 || x < 3)\n"

" a++;\n"

"}"

);

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x >= 3 || x < 3.\n", errout.str());

check("void f(int x) {\n"

" if (x > 3 || x <= 3)\n"

" a++;\n"

"}"

);

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x > 3 || x <= 3.\n", errout.str());

check("void f(int x) {\n"

" if((x==3) && (x!=4))\n"

" a++;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: If 'x == 3', the comparison 'x != 4' is always true.\n", errout.str());

check("void f(int x) {\n"

" if ((x!=4) && (x==3))\n"

" a++;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: If 'x == 3', the comparison 'x != 4' is always true.\n", errout.str());

check("void f(int x) {\n"

" if ((x==3) || (x!=4))\n"

" a++;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: If 'x == 3', the comparison 'x != 4' is always true.\n", errout.str());

check("void f(int x) {\n"

" if ((x!=4) || (x==3))\n"

" a++;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: If 'x == 3', the comparison 'x != 4' is always true.\n", errout.str());

check("void f(int x) {\n"

" if ((x==3) && (x!=3))\n"

" a++;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x == 3 && x != 3.\n", errout.str());

check("void f(int x) {\n"

" if ((x==6) || (x!=6))\n"

" a++;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x == 6 || x != 6.\n", errout.str());

check("void f(int x) {\n"

" if (x > 10 || x < 3)\n"

" a++;\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void f(int x) {\n"

" if (x > 5 && x == 1)\n"

" a++;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x > 5 && x == 1.\n", errout.str());

check("void f(int x) {\n"

" if (x > 5 && x == 6)\n"

" a++;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: If 'x == 6', the comparison 'x > 5' is always true.\n", errout.str());

// #3419

check("void f() {\n"

" if ( &q != &a && &q != &b ) { }\n"

"}");

ASSERT_EQUALS("", errout.str());

// #3676

check("void f(int m_x2, int w, int x) {\n"

" if (x + w - 1 > m_x2 || m_x2 < 0 )\n"

" m_x2 = x + w - 1;\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void f(float x) {\n" // x+1 => x

" if (x <= 1.0e20 && x >= -1.0e20) {}\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void f(float x) {\n" // x+1 => x

" if (x >= 1.0e20 && x <= 1.0e21) {}\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void f(float x) {\n" // x+1 => x

" if (x <= -1.0e20 && x >= -1.0e21) {}\n"

"}");

ASSERT_EQUALS("", errout.str());

}

void incorrectLogicOperator3() {

check("void f(int x, bool& b) {\n"

" b = x > 5 && x == 1;\n"

" c = x < 1 && x == 3;\n"

" d = x >= 5 && x == 1;\n"

" e = x <= 1 && x == 3;\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x > 5 && x == 1.\n"

"[test.cpp:3]: (warning) Logical conjunction always evaluates to false: x < 1 && x == 3.\n"

"[test.cpp:4]: (warning) Logical conjunction always evaluates to false: x >= 5 && x == 1.\n"

"[test.cpp:5]: (warning) Logical conjunction always evaluates to false: x <= 1 && x == 3.\n", errout.str());

}

void incorrectLogicOperator4() {

check("void f(int x) {\n"

" if (x && x != $0) {}\n"

"}");

ASSERT_EQUALS("", errout.str());

}

void incorrectLogicOperator5() { // complex expressions

check("void f(int x) {\n"

" if (x+3 > 2 || x+3 < 10) {}\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: EXPR > 2 || EXPR < 10.\n", errout.str());

}

void incorrectLogicOperator6() { // char literals

check("void f(char x) {\n"

" if (x == '1' || x == '2') {}\n"

"}");

ASSERT_EQUALS("", errout.str());

check("void f(char x) {\n"

" if (x == '1' && x == '2') {}\n"

"}");

TODO_ASSERT_EQUALS("error", "", errout.str());

}

void incorrectLogicOperator7() { // opposite expressions

check("void f(int i) {\n"

" if (i || !i) {}\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: i||!i.\n", errout.str());

check("void f(int a, int b) {\n"

" if (a>b || a<=b) {}\n"

"}");

TODO_ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: a>b||a<=b.\n", "", errout.str());

check("void f(int a, int b) {\n"

" if (a>b || a<b) {}\n"

"}");

ASSERT_EQUALS("", errout.str());

// #6064 False positive incorrectLogicOperator - invalid assumption about template type?

check("template<typename T> T icdf( const T uniform ) {\n"

" if ((0<uniform) && (uniform<1))\n"

" {}\n"

"}");

ASSERT_EQUALS("", errout.str());

// #6081 False positive: incorrectLogicOperator, with close negative comparisons

check("double neg = -1.0 - 1.0e-13;\n"

"void foo() {\n"

" if ((neg < -1.0) && (neg > -1.0 - 1.0e-12))\n"

" return;\n"

" else\n"

" return;\n"

"}");

TODO_ASSERT_EQUALS("", "[test.cpp:3]: (warning) Logical conjunction always evaluates to false: neg < -1.0 && neg > -1.0.\n", errout.str());

}

void incorrectLogicOperator8() { // opposite expressions

check("void f(int i) {\n"

" if (!(i!=10) && !(i!=20)) {}\n"

"}");

ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: !(i != 10) && !(i != 20).\n", errout.str());

}

void incorrectLogicOperator9() { // #6069 "False positive incorrectLogicOperator due to dynamic_cast"

check("class MyType;\n"

"class OtherType;\n"

"void foo (OtherType* obj) { \n"

" assert((!obj) || dynamic_cast<MyType*>(obj));\n"

"}");

ASSERT_EQUALS("", errout.str());

}