Replace file path separators with File.join

src/compiler/crystal/tools/doc/generator.cr

@@ -1,7 +1,7 @@
 class Crystal::Doc::Generator
   class Options
     property included_dirs = [] of String
-    property output_dir = "./docs"
+    property output_dir = "docs"
     property base_dir : String = Dir.current.chomp
   end
 
@@ -77,23 +77,23 @@ class Crystal::Doc::Generator
       body = ""
     end
 
-    File.write "#{@options.output_dir}/index.html", MainTemplate.new(body, types, repository_name)
+    File.write File.join(@options.output_dir, "index.html"), MainTemplate.new(body, types, repository_name)
   end
 
   def copy_files
-    Dir.mkdir_p "#{@options.output_dir}/css"
-    Dir.mkdir_p "#{@options.output_dir}/js"
+    Dir.mkdir_p File.join(@options.output_dir, "css")
+    Dir.mkdir_p File.join(@options.output_dir, "js")
 
-    File.write "#{@options.output_dir}/css/style.css", StyleTemplate.new
-    File.write "#{@options.output_dir}/js/doc.js", JsTypeTemplate.new
+    File.write File.join(@options.output_dir, "css", "style.css"), StyleTemplate.new
+    File.write File.join(@options.output_dir, "js", "doc.js"), JsTypeTemplate.new
   end
 
   def generate_types_docs(types, dir, all_types)
     types.each do |type|
       if type.program?
-        filename = "#{dir}/toplevel.html"
+        filename = File.join(dir, "toplevel.html")
       else
-        filename = "#{dir}/#{type.name}.html"
+        filename = File.join(dir, "#{type.name}.html")
       end
 
       File.write filename, TypeTemplate.new(type, all_types)
@@ -102,7 +102,7 @@ class Crystal::Doc::Generator
 
       subtypes = type.types
       if subtypes && !subtypes.empty?
-        dirname = "#{dir}/#{type.name}"
+        dirname = File.join(dir, type.name)
         Dir.mkdir_p dirname
         generate_types_docs subtypes, dirname, all_types
       end