Fix APA style initials for hyphenated first names

lib/cff/formatters/formatter.rb

@@ -40,8 +40,14 @@ def self.select_and_check_model(model, preferred_citation)
         model.authors.empty? || model.title.empty? ? nil : model
       end
 
+      def self.initial_from_name_part(part)
+        return part[0].capitalize unless part.include?('-')
+
+        part.split('-').filter_map { |sub| sub[0]&.capitalize }.join('.-')
+      end
+
       def self.initials(name)
-        name.split.map { |part| part[0].capitalize }.join('. ')
+        name.split.map { |part| initial_from_name_part(part) }.join('. ')
       end
 
       def self.note_from_model(model)

test/files/formatted/hyphenated-names.apa

@@ -0,0 +1 @@
+Kling, M.-U., Picard, J.-L., & Smith, J. (2021). Hyphenated names test [Computer software]

test/files/formatted/hyphenated-names.bibtex

@@ -0,0 +1,6 @@
+@software{Kling_Hyphenated_names_test_2021,
+author = {Kling, Marc-Uwe and Picard, Jean-Luc and Smith, John},
+month = sep,
+title = {{Hyphenated names test}},
+year = {2021}
+}

test/files/formatter/hyphenated-names.cff

@@ -0,0 +1,11 @@
+cff-version: 1.2.0
+message: If you use this software, please cite it as below.
+authors:
+  - family-names: Kling
+    given-names: Marc-Uwe
+  - family-names: Picard
+    given-names: Jean-Luc
+  - family-names: Smith
+    given-names: John
+title: Hyphenated names test
+date-released: 2021-09-21

test/formatters/formatter_test.rb

@@ -20,6 +20,21 @@
 require 'cff/index'
 
 class CFFFormatterTest < Minitest::Test
+  def test_initial_from_name_part
+    assert_equal 'A', CFF::Formatters::Formatter.initial_from_name_part('Arfon')
+    assert_equal 'M', CFF::Formatters::Formatter.initial_from_name_part('M.')
+    assert_equal 'M.-U', CFF::Formatters::Formatter.initial_from_name_part('Marc-Uwe')
+    assert_equal 'J.-L', CFF::Formatters::Formatter.initial_from_name_part('Jean-Luc')
+    assert_equal 'A.-B.-C', CFF::Formatters::Formatter.initial_from_name_part('A-B-C')
+  end
+
+  def test_initials
+    assert_equal 'A. M', CFF::Formatters::Formatter.initials('Arfon M.')
+    assert_equal 'M.-U', CFF::Formatters::Formatter.initials('Marc-Uwe')
+    assert_equal 'J.-L. P', CFF::Formatters::Formatter.initials('Jean-Luc Picard')
+    assert_equal 'A. B. C', CFF::Formatters::Formatter.initials('Arfon B. C.')
+  end
+
   def test_month_and_year_from_date
     [nil, '', ' ', 'nil'].each do |date|
       assert_equal(['', ''], CFF::Formatters::Formatter.month_and_year_from_date(date))