Use context instead of input in Gate

lib/mars/gate.rb

@@ -27,10 +27,9 @@ def initialize(name = "Gate", check: nil, fallbacks: nil, **kwargs)
 
     def run(context)
       context = ensure_context(context)
-      input = context.current_input
-      result = check.call(input)
+      result = check.call(context)
 
-      return input if result.nil? || result == :default
+      return context if result.nil? || result == :default
 
       branch = fallbacks[result]
       raise ArgumentError, "No fallback registered for #{result.inspect}" unless branch

spec/mars/gate_spec.rb

@@ -22,17 +22,17 @@ def run(context)
       it "passes through when check returns falsy" do
         gate = described_class.new(
           "PassGate",
-          check: ->(_input) {},
+          check: ->(_context) {},
           fallbacks: { fail: fallback_step }
         )
 
-        expect(gate.run("hello")).to eq("hello")
+        expect(gate.run("hello").current_input).to eq("hello")
       end
 
       it "returns the fallback branch result when check returns a registered key" do
         gate = described_class.new(
           "FailGate",
-          check: ->(_input) { :fail },
+          check: ->(_context) { :fail },
           fallbacks: { fail: fallback_step }
         )
 
@@ -43,7 +43,7 @@ def run(context)
       it "raises when check returns an unregistered key" do
         gate = described_class.new(
           "BadGate",
-          check: ->(_input) { :unknown },
+          check: ->(_context) { :unknown },
           fallbacks: { fail: fallback_step }
         )
 
@@ -53,7 +53,7 @@ def run(context)
       it "selects among multiple fallbacks" do
         gate = described_class.new(
           "MultiFallback",
-          check: ->(input) { input[:error_type] },
+          check: ->(context) { context.current_input[:error_type] },
           fallbacks: { timeout: fallback_step, auth: error_step }
         )
 
@@ -75,12 +75,12 @@ def run(context)
       it "uses check and fallback DSL" do
         cls = fallback_cls
         gate_class = Class.new(described_class) do
-          check { |input| :invalid if input.length > 5 }
+          check { |context| :invalid if context.current_input.length > 5 }
           fallback :invalid, cls
         end
 
         gate = gate_class.new("DSLGate")
-        expect(gate.run("hi")).to eq("hi")
+        expect(gate.run("hi").current_input).to eq("hi")
         expect(gate.run("longstring")).to eq("handled: longstring")
       end
     end