custom flag as compiler argument is not accessible from BugChecker

[dganesh5]

tried passing additional key value pair to Custom BugChecker following the instructions from this doc : http://errorprone.info/docs/flags

Tried setting this in pom

<compilerArgs> <arg>-XepOpt:mvnBuildDirectory=${project.build.directory}</arg> </compilerArgs>

And access using below code in MyCustomChecker
public MyCustomChecker(ErrorProneFlags flags) { this.pwd = flags.get("mvnBuildDirectory").toString(); }

upon running this, I get an java.util.ServiceConfigurationError.
java.util.ServiceConfigurationError: com.google.errorprone.bugpatterns.BugChecker: Provider com.abc.errorprone.MyCustomChecker could not be instantiated

[nick-someone]

Ah, sorry about that!

Due to the requirements of ServiceLoader, the object must still have a no-arg constructor. However, if you have another constructor with ErrorProneFlags as a parameter, it will be picked up.

See #691