GCCollector: user keyword arguments for construction.

src/Prometheus.jl

@@ -630,7 +630,7 @@ include("process_collector.jl")
 
 # Default registry and collectors
 const DEFAULT_REGISTRY = CollectorRegistry()
-const GC_COLLECTOR = GCCollector(DEFAULT_REGISTRY)
+const GC_COLLECTOR = GCCollector(; registry=DEFAULT_REGISTRY)
 const PROCESS_COLLECTOR = ProcessCollector(DEFAULT_REGISTRY)
 
 end # module Prometheus

src/gc_collector.jl

@@ -3,7 +3,7 @@
 ############################
 
 mutable struct GCCollector <: Collector
-    function GCCollector(registry::Union{CollectorRegistry, Nothing}=DEFAULT_REGISTRY)
+    function GCCollector(; registry::Union{CollectorRegistry, Nothing}=DEFAULT_REGISTRY)
         gcc = new()
         if registry !== nothing
             register(registry, gcc)

test/runtests.jl

@@ -281,7 +281,7 @@ end
 
 @testset "Prometheus.GCCollector" begin
     r = Prometheus.CollectorRegistry()
-    c = Prometheus.GCCollector(r)
+    c = Prometheus.GCCollector(; registry=r)
     @test c in r.collectors
     # Record before and after stats and test that the metrics are in between
     old_stats = Base.gc_num()