Fix collection option related issue

We have recently added support to provide collection options either
as an command line arguments or options in the collection file. But
that is only working on the site interface, and the collection cli
still expect the `output-folder` as required option.

This commit changes that, so it's not required anymore and it will
try to read the option from the file, and if none of those source
has this value, only then raise a missing option error.

Fixes #283

lib/metanorma/cli/collection.rb

@@ -15,6 +15,7 @@ def self.render(filename, options = {})
 
       def render
         extract_options_from_file
+        verify_required_options_are_present
         collection_file.render(collection_options.compact)
       end
 
@@ -26,8 +27,14 @@ def collection_file
         @collection_file ||= Metanorma::Collection.parse(file)
       end
 
+      def verify_required_options_are_present
+        if collection_options[:output_folder].nil?
+          raise ArgumentError.new("Missing a required option '--output-folder'")
+        end
+      end
+
       def collection_options
-        {
+        @collection_options ||= {
           compile: @compile_options,
           coverpage: options.fetch(:coverpage, nil),
           output_folder: options.fetch(:output_folder, nil),

lib/metanorma/cli/command.rb

@@ -59,7 +59,7 @@ def compile(file_name = nil)
 
       desc "collection FILENAME", "Render HTML pages from XML/YAML colection"
       option :format, aliases: "-x", type: :string, desc: "Formats to generate"
-      option :output_folder, aliases: "-w", required: true, desc: "Directory to save compiled files"
+      option :output_folder, aliases: "-w", desc: "Directory to save compiled files"
       option :coverpage, aliases: "-c", desc: "Liquid template"
       option :agree_to_terms, type: :boolean, desc: "Agree / Disagree with all third-party licensing terms "\
                                                     "presented (WARNING: do know what you are agreeing with!)"

spec/acceptance/collection_spec.rb

@@ -11,6 +11,13 @@
       run_metanorma_collection("collection1.xml")
       expect_generated_files_to_match_expectations
     end
+
+    it "only raises error when the file/cli doesn't include output option" do
+      command = %W(collection collection1.xml -x html --no-install-fonts )
+      output = capture_stdout { Metanorma::Cli.start(command) }
+
+      expect(output).to include("Missing a required option '--output-folder'")
+    end
   end
 
   around(:each) do |example|

spec/metanorma/cli/collection_spec.rb

@@ -5,9 +5,16 @@
     context "with specified options" do
       it "compiles and renders the collection files" do
         collection = mock_collection_instance
-        Metanorma::Cli::Collection.render(collection_file, format: "html, pdf")
 
-        expect(collection).to have_received(:render).with(format: %I(html pdf))
+        Metanorma::Cli::Collection.render(
+          collection_file,
+          format: "html, pdf",
+          output_folder: "bilingual-brochure",
+        )
+
+        expect(collection).to have_received(:render).with(
+          format: %I(html pdf), output_folder: "bilingual-brochure"
+        )
       end
     end
 
@@ -25,6 +32,15 @@
         )
       end
     end
+
+    it "validates the required attributes" do
+      collection = mock_collection_instance
+
+      expect {
+        Metanorma::Cli::Collection.render(collection_file)
+      }.to raise_error(ArgumentError)
+      expect(collection).not_to have_received(:render)
+    end
   end
 
   def collection_file(collection = "collection1.yml")