make for=outer in tab optional

Author: bishabosha

_plugins/jekyll-tabs-lib/jekyll-tabs-4scala.rb

@@ -43,8 +43,13 @@ def initialize(block_name, markup, tokens)
             def render(context)
                 environment = context.environments.first
                 environment["tabs-#{@name}"] = [] # reset every time (so page translations can use the same name)
-                super
-
+                if environment["CURRENT_TABS_ENV"].nil?
+                    environment["CURRENT_TABS_ENV"] = @name
+                else
+                    raise SyntaxError.new("Nested tabs are not supported")
+                end
+                super # super call renders the internal content
+                environment["CURRENT_TABS_ENV"] = nil # reset after rendering
                 foundDefault = false
 
                 allTabs = environment["tabs-#{@name}"]
@@ -87,15 +92,17 @@ def render(context)
         class TabBlock < Liquid::Block
             alias_method :render_block, :render
 
-            SYNTAX = /^\s*(#{Liquid::QuotedFragment})\s+(?:for=(#{Liquid::QuotedFragment}))(?:\s+(defaultTab))?/o
+            SYNTAX = /^\s*(#{Liquid::QuotedFragment})\s+(?:for=(#{Liquid::QuotedFragment}))?(?:\s+(defaultTab))?/o
             Syntax = SYNTAX
 
             def initialize(block_name, markup, tokens)
                 super
 
                 if markup =~ SYNTAX
                     @tab = Tabs::unquote($1)
-                    @name = Tabs::unquote($2)
+                    if $2
+                        @name = Tabs::unquote($2)
+                    end
                     @anchor = Tabs::asAnchor(@tab)
                     if $3
                         @defaultTab = true
@@ -113,8 +120,16 @@ def render(context)
                 content = converter.convert(pre_content)
                 tabcontent = TabDetails.new(label: @tab, anchor: @anchor, defaultTab: @defaultTab, content: content)
                 environment = context.environments.first
-                environment["tabs-#{@name}"] ||= []
-                environment["tabs-#{@name}"] << tabcontent
+                tab_env = environment["CURRENT_TABS_ENV"]
+                if tab_env.nil?
+                    raise SyntaxError.new("Tab block '#{tabcontent.label}' must be inside a tabs block")
+                end
+                if !@name.nil? && tab_env != @name
+                    raise SyntaxError.new(
+                        "Tab block '#{@tab}' for=#{@name} does not match its enclosing tabs block #{tab_env}")
+                end
+                environment["tabs-#{tab_env}"] ||= []
+                environment["tabs-#{tab_env}"] << tabcontent
             end
         end
     end