V7013. Suspicious assignment in the condition. A comparison may have been intended.

The analyzer has detected an assignment in a condition. The comparison operator was most likely intended instead of assignment.

The example:

function foo() {
  let mode = ....;

  if (mode = 1) {  // <=
    return; 
  } 
  ....
}

The code contains a typo: instead of comparing the mode variable to one, a value is assigned. As a result, the condition is always true, and the code does not work as originally intended.

The fixed code:

if (mode == 1) {
  ....
}

In some cases, using an assignment inside a condition can shorten the code:

let result = ....; 
while (result = exec()) {
  ....
}

Note. This approach is highly inadvisable because determining whether it is a typo or an attempt to shorten the code takes more time.

If the assignment is still required, it can be enclosed in parentheses:

while ((result = exec()))
  ....

The analyzer and many compilers/interpreters treat such code as safe. It also informs developers that the code is error-free.

This diagnostic rule is classified as:

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