[GROOVY-8490] Extend @Newify to support a class name pattern parameter

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.6.0-alpha-4, 2.5.0-rc-2, 3.0.0-alpha-3
• Component/s: Compiler
• Assignee: Daniel Sun
• Reporter: mgroovy
• Created: 04/Mar/18 21:50
• Updated: 26/Jul/18 04:38
• Resolved: 22/Apr/18 23:46

Description

• @Newify should be extended to support a classNamePattern parameter
• All class names inside e.g. a @Newify annotated class that match the given pattern shall support having its ctor called without the new keyword ("Python style")
• Example:

  @Newify(classNamePattern=/[A-Z].*/)
  class Foo {
    // Any class whose name starts with an uppercase letter
    // can have its ctors called without new keyword inside Foo
    
    String s
    Integer x
    File f
    
    Foo(String s, File f, Integer x) { 
      this.s = s
      this.f = f
      this.x = x
    }
    
    void createFoo(File base) {
      // Java style
      new Foo(new String('abc'), new File(base,'log'), new Integer(123))
      // new Groovy style
      Foo(String('abc'), File(base,'log'), Integer(123))
    }
  } 
  

• The classNamePattern parameter:
  1. Is 100% backwards compatible (same as the existing value parameter)
  2. Would allow e.g. @Newify(classNamePattern=/[A-Z].*/) to be auto-applied to all classes in a project (same as e.g. @AutoFinal (GROOVY-8300))
     • In practice that would typically cover 99.9...% of all classes, since most projects follow the Java convention of classes being the only callable entities to start with an uppercase letter
     • The existing value parameter cannot be used that way on a global level, since it is not practical to explicitly list all project classes
  3. Compile time performance wise classNamePattern=/[A-Z].*/ avoids having to check any (method/field/variable)() call whether it is a class ctor call if it is lowercase (i.e. again typically in 99.9...% of cases), i.e. the approach is fast

Issue Links

• is related to: GROOVY-8491 @NamingConvention: Supply class/method/field/... name patterns to compiler