params('query') returns undef until params() has been called

Status: confirmed against main @ 21bc21d9

lib/Dancer2/Core/Request.pm:130 and 346-349. _query_params is a bare hash read with no lazy builder, unlike its two siblings which both self-initialise:

sub _body_params  { $_[0]->{'_body_params'}  ||= $_[0]->body_parameters->as_hashref_mixed }
sub _query_params { $_[0]->{'_query_params'} }                      # <-- no ||=
sub _route_params { $_[0]->{'_route_params'} ||= {} }

Reproduction

A) params("query") BEFORE any params() call: UNDEF
B) params("query") AFTER  params() call    : hashref

Impact

It usually works inside a route handler, because dispatch calls _set_route_params → _build_params → _parse_get_params on the way in. It breaks in early hooks that run before route matching, and in any code path reaching params('query') first. In list context it is worse — %{ undef }.

Suggested fix

sub _query_params { $_[0]->{'_query_params'} ||= $_[0]->_parse_get_params }

Note _parse_get_params already returns early with $self->_query_params when the value is set (line 539). That guard still terminates once the accessor is lazy, because _set_query_params writes the hash element directly rather than going through the accessor — but it is subtle enough to deserve a test.

Suggested test

params('query') returns a hashref on a fresh request with no prior params() call.

Start in lib/Dancer2/Core/Request.pm at _query_params around line 130 and the related logic around lines 346-349 and 539. Verify params('query') on a fresh request before any params() call, then add coverage showing it returns a hashref and that the existing lazy-parse guard still behaves correctly.