Cannot convert PathVariable Map<String,String> when building link

In building some infrastructure, we want to use a Map for the path variables

public List<Resource> list(@PathVariable Map<String, String> pathVariables) { ... }

However when we want to build a list using a map:

methodOn(TheController.class).list(mapOfPathVariables)

We get:

org.springframework.core.convert.ConverterNotFoundException: No converter found capable of converting from type [@org.springframework.web.bind.annotation.PathVariable java.util.Map<java.lang.String, java.lang.String>] to type [java.lang.String]
	at org.springframework.core.convert.support.GenericConversionService.handleConverterNotFound(GenericConversionService.java:324) ~[spring-core-4.3.5.RELEASE.jar:4.3.5.RELEASE]
	at org.springframework.core.convert.support.GenericConversionService.convert(GenericConversionService.java:206) ~[spring-core-4.3.5.RELEASE.jar:4.3.5.RELEASE]
	at org.springframework.hateoas.mvc.AnnotatedParametersParameterAccessor$BoundMethodParameter.asString(AnnotatedParametersParameterAccessor.java:192) ~[spring-hateoas-0.23.0.RELEASE.jar:na]
	at org.springframework.hateoas.mvc.ControllerLinkBuilderFactory.linkTo(ControllerLinkBuilderFactory.java:150) ~[spring-hateoas-0.23.0.RELEASE.jar:na]
	at org.springframework.hateoas.mvc.ControllerLinkBuilder.linkTo(ControllerLinkBuilder.java:193) ~[spring-hateoas-0.23.0.RELEASE.jar:na]

Looking at exiting PRs, it seems that a similar issue for property placeholders is in progress on @gregturn's PR #602

Start with AnnotatedParametersParameterAccessor.BoundMethodParameter.asString and the link-building path through ControllerLinkBuilderFactory.linkTo, using the controller and Map invocation shown in the report. Reproduce the ConverterNotFoundException, then verify that building the link accepts the map path variables without that conversion failure.