Fix inline component throws error with strip_trailing_whitespace (#2015)

* add rstrip failing test case

* simplify failing tests

* final failig  test revision

* fix failing tests

* add: changelog entry

* fix linting errors

* add: inline benchmark

* refcator benchmark

* fix: linting

* Update docs/CHANGELOG.md

---------

Co-authored-by: Hans Lemuet <Spone@users.noreply.github.com>

Rakefile

@@ -30,6 +30,10 @@ task :slots_benchmark do
   ruby "./performance/slots_benchmark.rb"
 end
 
+task :inline_components_benchmark do
+  ruby "./performance/inline_benchmark.rb"
+end
+
 namespace :coverage do
   task :report do
     require "simplecov"

docs/CHANGELOG.md

@@ -10,6 +10,10 @@ nav_order: 5
 
 ## main
 
+* Fixed a bug where inline templates where unable to remove trailing whitespace without throwing an error.
+
+    *Reegan Viljoen*
+
 ## 3.12.1
 
 * Ensure content is rendered correctly for forwarded slots.

lib/view_component/compiler.rb

@@ -247,9 +247,9 @@ def variants_from_inline_calls(calls)
 
     def compiled_inline_template(template)
       handler = ActionView::Template.handler_for_extension(template.language)
-      template.rstrip! if component_class.strip_trailing_whitespace?
+      template = template.source.dup
 
-      compile_template(template.source, handler)
+      compile_template(template, handler)
     end
 
     def compiled_template(file_path)

performance/components/new_inline_component.rb

@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+class Performance::NewInlineComponent < ViewComponent::Base
+  class NestedComponent < ViewComponent::Base
+    def initialize(name:)
+      @name = name
+    end
+
+    erb_template <<~ERB
+      <p>nested hello #{@name}</p>
+    ERB
+  end
+
+  def initialize(name:)
+    @name = name
+  end
+
+  erb_template <<~ERB
+    <h1>hello #{@name}</h1>
+    <%=
+      safe_join(
+        [
+          content,
+          50.times.map { render NestedComponent.new(name: @name) }
+        ],
+        "\n\n"
+      )
+    %>
+  ERB
+end

performance/inline_benchmark.rb

@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+# Run `bundle exec rake benchmark` to execute benchmark.
+# This is very much a work-in-progress. Please feel free to make/suggest improvements!
+
+require "benchmark/ips"
+
+# Configure Rails Environment
+ENV["RAILS_ENV"] = "production"
+require File.expand_path("../test/sandbox/config/environment.rb", __dir__)
+
+module Performance
+  require_relative "components/new_inline_component"
+end
+
+class BenchmarksController < ActionController::Base
+end
+
+BenchmarksController.view_paths = [File.expand_path("./views", __dir__)]
+controller_view = BenchmarksController.new.view_context
+
+Benchmark.ips do |x|
+  x.time = 10
+  x.warmup = 2
+
+  x.report("inline_component") do
+    controller_view.render(Performance::NewInlineComponent.new(name: "Reegan"))
+  end
+
+  x.compare!
+end

test/sandbox/app/components/inline_trailing_whitespace_component.rb

@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+class InlineTrailingWhitespaceComponent < ViewComponent::Base
+  strip_trailing_whitespace
+
+  erb_template <<~ERB
+
+    <h1>Template does not contain any trailing whitespace</h1>
+  ERB
+end

test/sandbox/test/rendering_test.rb

@@ -1113,4 +1113,12 @@ def test_use_helper
     render_inline(UseHelpersComponent.new)
     assert_selector ".helper__message", text: "Hello helper method"
   end
+
+  def test_inline_component_renders_without_trailing_whitespace
+    without_template_annotations do
+      render_inline(InlineTrailingWhitespaceComponent.new)
+    end
+
+    refute @rendered_content =~ /\s+\z/, "Rendered component contains trailing whitespace"
+  end
 end