Splat flows/adapters passed to Rackstash::Logger#initialize

This ensures that we are not unduely altering (i.e. flattening) adapter
specifications when creating the flows.

lib/rackstash/flows.rb

@@ -19,7 +19,7 @@ module Rackstash
     def initialize(*flows)
       @flows = Concurrent::Array.new
 
-      flows.flatten.each do |flow|
+      flows.each do |flow|
         add(flow)
       end
     end

lib/rackstash/logger.rb

@@ -57,10 +57,10 @@ module Rackstash
     #   By default we use {PROGNAME}.
     # @param formatter [#call] the log formatter for each individual buffered
     #   line. See {#formatter} for details.
-    def initialize(flows, level: DEBUG, progname: PROGNAME, formatter: Formatter.new)
+    def initialize(*flows, level: DEBUG, progname: PROGNAME, formatter: Formatter.new)
       @buffer_stack = Concurrent::ThreadLocalVar.new
 
-      @sink = Rackstash::Sink.new(flows)
+      @sink = Rackstash::Sink.new(*flows)
       self.level = level
       self.progname = progname
       self.formatter = formatter

lib/rackstash/sink.rb

@@ -15,8 +15,8 @@ module Rackstash
     # @param flows [Array<Flow, Object>, Flow, Adapters::Adapter, Object]
     #   an array of {Flow}s or a single {Flow}, respectivly object which can be
     #   used as a {Flow}'s adapter. See {Flow#initialize}.
-    def initialize(flows)
-      @flows = Rackstash::Flows.new(flows)
+    def initialize(*flows)
+      @flows = Rackstash::Flows.new(*flows)
 
       @default_fields = {}
       @default_tags = []

spec/rackstash/flows_spec.rb

@@ -27,9 +27,6 @@ describe Rackstash::Flows do
     it 'accepts a list of flows' do
       raw_flows = Array.new(3) { a_flow }
 
-      list_with_array = described_class.new(raw_flows)
-      expect(list_with_array.size).to eql 3
-
       list_with_splat = described_class.new(*raw_flows)
       expect(list_with_splat.size).to eql 3
     end

spec/rackstash/sink_spec.rb

@@ -19,27 +19,27 @@ describe Rackstash::Sink do
     flow
   end
 
-  let(:flow) { a_flow }
-  let(:sink) { described_class.new(flow) }
+  let(:flows) { [a_flow] }
+  let(:sink) { described_class.new(*flows) }
 
   describe 'initialize' do
     # We deliberately use the real Rackstash::Flows class here to server as an
     # integration test
     it 'wraps a single flow in a flows list' do
-      expect(Rackstash::Flows).to receive(:new).with(flow)
+      expect(Rackstash::Flows).to receive(:new).with(*flows)
         .and_call_original
 
-      sink = described_class.new(flow)
+      sink = described_class.new(*flows)
       expect(sink.flows).to be_a Rackstash::Flows
-      expect(sink.flows.to_a).to eql [flow]
+      expect(sink.flows.to_a).to eql flows
     end
 
     it 'wraps multiple flows in a flows list' do
       flows = [a_flow, a_flow]
 
-      expect(Rackstash::Flows).to receive(:new).with(flows)
+      expect(Rackstash::Flows).to receive(:new).with(*flows)
         .and_call_original
-      sink = described_class.new(flows)
+      sink = described_class.new(*flows)
 
       expect(sink.flows).to be_a Rackstash::Flows
       expect(sink.flows.to_a).to eql flows
@@ -111,19 +111,19 @@ describe Rackstash::Sink do
   end
 
   describe '#close' do
-    let(:flow) { [a_flow, a_flow] }
+    let(:flows) { [a_flow, a_flow] }
 
     it 'calls close on all flows' do
-      expect(flow).to all receive(:close)
+      expect(flows).to all receive(:close)
       expect(sink.close).to be_nil
     end
   end
 
   describe '#reopen' do
-    let(:flow) { [a_flow, a_flow] }
+    let(:flows) { [a_flow, a_flow] }
 
     it 'calls reopen on all flows' do
-      expect(flow).to all receive(:reopen)
+      expect(flows).to all receive(:reopen)
       expect(sink.reopen).to be_nil
     end
   end
@@ -134,7 +134,6 @@ describe Rackstash::Sink do
         allow(flow).to receive(:write)
       end
     }
-    let(:sink) { described_class.new(flows) }
     let(:buffer) { Rackstash::Buffer.new(sink) }
 
     it 'merges default_fields and default_tags' do