Added kwargs support to retry. (#21419)

* Added kwargs support to `retry`.

* Updated retry example in doc string and added a couple tests.

Author: Rory Finnegan

base/error.jl

@@ -128,15 +128,15 @@ retry(f, delays=fill(5.0, 3))
 retry(f, delays=rand(5:10, 2))
 retry(f, delays=Base.ExponentialBackOff(n=3, first_delay=5, max_delay=1000))
 retry(http_get, check=(s,e)->e.status == "503")(url)
-retry(read, check=(s,e)->isa(e, UVError))(io)
+retry(read, check=(s,e)->isa(e, UVError))(io, 128; all=false)
 ```
 """
 function retry(f::Function;  delays=ExponentialBackOff(), check=nothing)
-    (args...) -> begin
+    (args...; kwargs...) -> begin
         state = start(delays)
         while true
             try
-                return f(args...)
+                return f(args...; kwargs...)
             catch e
                 done(delays, state) && rethrow(e)
                 if check !== nothing

test/error.jl

@@ -63,4 +63,9 @@ let
     @test typeof(ex) == ErrorException
     @test ex.msg == "foo"
     @test c[1] == 1
+
+    # Functions with keyword arguments
+    foo_kwargs(x; y=5) = x + y
+    @test retry(foo_kwargs)(3) == 8
+    @test retry(foo_kwargs)(3; y=4) == 7
 end