Keep relative imports at the end when sorting (#126)

features/component_generator.feature

@@ -113,6 +113,34 @@ Feature: Component generator
     import "components/world/world";
     """
 
+  Scenario: relative `imports` in JavaScript files kept at the end when generating a component
+    When I cd to "frontend/components"
+    And a file named "index.js" with:
+    """
+    import "../a_relative_file.js";
+    import "../other_relative_file.js";
+    """
+    Then the file named "index.js" should contain:
+    """
+    import "../a_relative_file.js";
+    import "../other_relative_file.js";
+    """
+    When I run `rails generate component button`
+    Then the file named "index.js" should contain:
+    """
+    import "components/button/button";
+    import "../a_relative_file.js";
+    import "../other_relative_file.js";
+    """
+    When I run `rails generate component awesome_button`
+    Then the file named "index.js" should contain:
+    """
+    import "components/awesome_button/awesome_button";
+    import "components/button/button";
+    import "../a_relative_file.js";
+    import "../other_relative_file.js";
+    """
+
   Scenario: Generate component with `erb` template engine
     When I run `rails generate component AwesomeButton`
     And I cd to "frontend/components/awesome_button"

lib/generators/component/component_generator.rb

@@ -169,14 +169,26 @@ def app_generators
   end
 
   def sort_lines_alphabetically!(path)
+    relative_imports, imports = read_imports_from_path(path)
+
+    return if imports.empty?
+
+    imports = imports.uniq.sort + relative_imports
+
+    write_imports_to_path(imports, path)
+  end
+
+  def read_imports_from_path(path)
     lines = File.readlines(path).map do |line|
       line if line =~ /^import ["'](.*)["'];$/
     end.compact
 
-    return if lines.empty?
-
-    lines = lines.uniq.sort
+    lines.partition do |l|
+      l =~ /^import ["']\.(.*)["'];$/
+    end
+  end
 
+  def write_imports_to_path(lines, path)
     File.open(path, "w") do |f|
       lines.each do |line|
         f.write(line)