Move the action call body in to a method with a strict return type to…

… ensure early returns work and allows Crystal to handle the return type compile errors. Fixes #1843 (#1857)

spec/lucky/action_spec.cr

@@ -223,6 +223,17 @@ class Tests::ComponentActionWithCustomContentType < TestAction
   end
 end
 
+class Tests::MultiConditionWithEarlyReturn < TestAction
+  get "/tests/multi_condition_with_early_return" do
+    data = {check: 1}
+    if data
+      return json(data)
+    end
+
+    raw_json("{}")
+  end
+end
+
 describe Lucky::Action do
   it "has a url helper" do
     Lucky::RouteHelper.temp_config(base_uri: "example.com") do
@@ -231,6 +242,11 @@ describe Lucky::Action do
     end
   end
 
+  it "allows for early returns" do
+    response = Tests::MultiConditionWithEarlyReturn.new(build_context, params).call
+    response.body.to_s.should eq "{\"check\":1}"
+  end
+
   describe ".url_without_query_params" do
     it "returns url without declared non-nil query params" do
       Lucky::RouteHelper.temp_config(base_uri: "example.com") do

src/lucky/routable.cr

@@ -87,6 +87,12 @@ module Lucky::Routable
 
   # :nodoc:
   macro setup_call_method(body)
+    # Return a response with `html`, `redirect`, or `json` at the end of your action.
+    # Ensure all conditionals (like if/else) return a response with html, redirect, json, etc.
+    private def action_call_body : Lucky::Response
+      {{ body }}
+    end
+
     def call
       # Ensure clients_desired_format is cached by calling it
       clients_desired_format
@@ -96,7 +102,7 @@ module Lucky::Routable
       %response = if %pipe_result.is_a?(Lucky::Response)
         %pipe_result
       else
-        {{ body }}
+        action_call_body
       end
 
       %pipe_result = run_after_pipes