This is a groovy expression.

There is a utility class which implements Levenshtien distance to select different combinations.
The default is a distance of 12, which means to say all the capabilities have to be at least 12 characters different.

There are two objects available to the expression

• current
• selected

current is the next object candidate to add with three properties
selected is a list of the already added objects
The properties available are

• String browserName
• String platformName
• String browserVersion

and toString() returns the axis value.

Examples (you need to import the Levenshtien class to use it)

        import org.jenkinsci.plugins.Levenshtien

        def different = true
        selected.any {
          if (Levenshtien.distance(current.browserName, it.browserName) < 1) {
            different = false
            true
          }
          if (Levenshtien.distance(current.platformName, it.platformName) < 1) {
            different = false
            true
          }
          if (Levenshtien.distance(current.toString(), it.toString()) < 12) {
            different = false
            true
          }
        }
        return different
    

This example ensures the browser, platform and label are distinct.