Create rule S8346: Increment and decrement operators (++/--) should not be used with floating point variables.

[github-actions]

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Description

Increment and decrement operators (++ and --) shouldn't be used with floating-point variables (like float or double). While the language allows it, the usage is not idiomatic and most developers intuitively expect x++ to apply to integer types. Using it on a float violates this common expectation and can lead to misleading code.

In particular floating point arithmetic has some non-intuitive properties, which can lead to unexpected bugs. For example, the following loop will not terminate:

for (float x = 16_000_000; x < 17_000_000; x++) {
  // ...
}
// The loop does not terminate

This happens because float has only 24 bits of precision and once a number gets large enough, adding 1.0 becomes insignificant.

The problem would not occur if int is used instead of float, even though both bytes occupy 32 bits.

for (int x = 16_000_000; x < 17_000_000; x++) {
  // ...
}
// This loop terminates.

Noncompliant code

x++;
y--;

Compliant code

x += 1.0;
y -= 1.0;

[sonarqube-next]

Quality Gate passed for 'rspec-tools'

Issues
0 New issues
0 Fixed issues
0 Accepted issues

Measures
0 Security Hotspots
0 Dependency risks
No data about Coverage
No data about Duplication

See analysis details on SonarQube

[sonarqube-next]

Quality Gate passed for 'rspec-frontend'

Issues
0 New issues
0 Fixed issues
0 Accepted issues

Measures
0 Security Hotspots
0 Dependency risks
No data about Coverage
No data about Duplication

See analysis details on SonarQube

[tomasz-tylenda-sonarsource]

Let's merge it with the previous sentence to improve flow. For example, "adding 1.0 becomes insignificant and the operation does nothing"

[tomasz-tylenda-sonarsource]

How about we move this sentence to "How to fix it"?