Operands always having the same value should be avoided

  • SAME_OPERAND_VALUE
  • Code Quality
  • Medium
  • No tags

This rule applies when the operation's result is fixed because operands have the same value always.

For example, the result of x - x is 0 for all values of x except NaN.

It is recommended to use the constant value because it is often indistinguishable from mistake.

The following operators are considered: -, /, %, ^, <, >, =, >=, ==, !=, ===, !==

Noncompliant Code Example

// Example 1
if (x) {
    diff = x - y;
} else {
    x = y;
    diff = x - y; // SAME_OPERAND_VALUE alarm. The result is always 0.
}

// Example 2
if (value > maxValue) {
    value = maxValue;
    diff = value - maxValue; // SAME_OPERAND_VALUE alarm. The result is always 0.
}

Compliant Code Example

// Example 1
if (x) {
    diff = x - y;
} else {
    x = y;
    diff = 0;
}

// Example 2
if (value > maxValue) {
  diff = value - maxValue;
  value = maxValue;
}

Version

This rule was introduced in DeepScan 1.0.0-alpha.