Fix: Add support for rendering multiple scopes by passing string as names

[swilgosz]

Background

Resolves: #252

Bug 1.

When scope name is passed as string (either scope class name, or the path to the file), the name resolving goes through the cache, with a hardcoded key scope_class, not allowing mutliple scopes to be stored and fetched.

Bug 2.

If namespace is not defined (nil), const_defined? is called on nil, causing Undefined method error to be risen.

Design

• Add spec covering both issues detected.
• Change the hardcoded cache key to the one taking passed name into the consideration
• Add support to nil namespace, falling back to the Object, so we can use const_get and const_defined? methods.

[bkuhlmann]

I ran into this too. Without this patch, use of multiple scopes is essentially useless which defeats the power they provide. It would be good to get this folded in and a patch released shortly after.

[bkuhlmann]

💡 If it helps, in my local patch, I only use name which is all you need to store in the cache. Example:

View.cache.fetch_or_store name, rendering.config do
  # Implementation details.
end

[bkuhlmann]

💡 If it helps, in my local patch, I needed a way to test that the cache works as expected and ended up with the following spec:

Spec Snippet

RSpec.describe Milestoner::Views::ScopeBuilder do
  subject(:builder) { described_class }

  let :view do
    Class.new Hanami::View do
      config.paths = Bundler.root.join "lib/milestoner/templates"
      config.template = "n/a"
    end
  end

  let(:scope_a) { Class.new Hanami::View::Scope }
  let(:scope_b) { Class.new Hanami::View::Scope }

  before do
    stub_const "TestScopeA", scope_a
    stub_const "TestScopeB", scope_b
    Hanami::View.cache.cache.clear
  end

  describe ".call" do
    it "caches scope without duplicates" do
      builder.call TestScopeA, locals: {}, rendering: view.new.rendering
      builder.call TestScopeB, locals: {}, rendering: view.new.rendering
      builder.call "TestScopeA", locals: {}, rendering: view.new.rendering
      builder.call "TestScopeB", locals: {}, rendering: view.new.rendering
      builder.call scope_a, locals: {}, rendering: view.new.rendering
      builder.call scope_b, locals: {}, rendering: view.new.rendering

      expect(Hanami::View.cache.cache.values).to eq([TestScopeA, TestScopeB])
    end
  end
end

Might be a good idea to add a spec for #call because that ensures the cache is used and doesn't duplicate itself. This also means you'd need to clear the cache between specs which why I put the in the before block.