[GROOVY-11119] String and Pattern conflict

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.5.22, 3.0.18, 4.0.13
• Fix Version/s: 4.0.14, 3.0.19
• Component/s: Static compilation

Language

groovy

• Assignee: Eric Milles
• Reporter: A. Lepe
• Created: 07/Jul/23 07:06
• Updated: 13/Aug/24 21:20
• Resolved: 10/Jul/23 17:23

Description

I'm not sure if its a bug or I am doing something wrong, but it is a little bit strange:

Consider the following class:

 

// code placeholder
@CompileStatic
static class Search {
    private String keyword
    private Pattern pattern
    private int code = 0
    void setCriteria(String keyword) {
        this.keyword = keyword
        code = 1
    }
    void setCriteria(Pattern pattern) {
        this.pattern = pattern
        code = 2
    }
    int getCode() {
        return code
    }
}
 

Now if you execute:

// code placeholder
String kw = "something"
assert new Search(
     criteria: kw
).code == 1        

Pattern p = ~/\w+/
assert p instanceof Pattern
assert new Search(
     criteria: p
).code == 2  // fails as value returned is 1

It fails as it is calling the `setCriteria(String)` instead of `setCriteria(Pattern)`. I'm not sure if that is the expected behavior.

 

One thing to note is that the above code works without issues when compiling dynamically. 

Another strange behavior is that if `setCriteria(Pattern)` is declared before `setCriteria(String)`, it fails to compile:

 

// code placeholder
@CompileStatic
static class Search {
    private String keyword
    private Pattern pattern
    private int code = 0

    // Pattern before String:
    void setCriteria(Pattern pattern) {
        this.pattern = pattern
        code = 2
    }
    void setCriteria(String keyword) {
        this.keyword = keyword
        code = 1
    }
    int getCode() {
        return code
    }
} 

new Search(
     criteria: "hello"  // <---- will fail here 
)

The error thrown is: 

Cannot cast object 'hello' with class 'java.lang.String' to class 'java.util.regex.Pattern'

Again, without `@CompileStatic` works fine.

 

It seems to happen in all Groovy versions (2.X, 3.X and 4.X).

NOTE: I maintain a library which is developed with Groovy, but that can be used from Java or Kotlin, for that reason I need to support `Pattern` class outside Groovy.

I have created a testing code in case you need it:

https://gitlab.com/intellisrc/groovy-bugs/-/tree/string-pattern

Issue Links

• relates to: GROOVY-11451 IncompatibleClassChange with map-style constructor and overloaded setters