tags: don't allow tags to begin with a '/'.

Disallow tags from starting with a '/' character. This is so that tag
abbreviations in autocomplete, which start with a '/', don't conflict
with regular tags.

Also disallow some other punctuation characters: `%{})]. Currently no
tags start with these characters. This is to reserve other special
characters in case we need them for other future syntax extensions.

app/logical/tag_name_validator.rb

@@ -7,12 +7,8 @@ class TagNameValidator < ActiveModel::EachValidator
       record.errors.add(attribute, "'#{value}' cannot contain asterisks ('*')")
     when /,/
       record.errors.add(attribute, "'#{value}' cannot contain commas (',')")
-    when /\A~/
+    when /\A[-~_`%){}\]\/]/
-      record.errors.add(attribute, "'#{value}' cannot begin with a tilde ('~')")
+      record.errors.add(attribute, "'#{value}' cannot begin with a '#{value[0]}'")
-    when /\A-/
-      record.errors.add(attribute, "'#{value}' cannot begin with a dash ('-')")
-    when /\A_/
-      record.errors.add(attribute, "'#{value}' cannot begin with an underscore")
     when /_\z/
       record.errors.add(attribute, "'#{value}' cannot end with an underscore")
     when /__/

test/unit/autocomplete_service_test.rb

@@ -97,16 +97,6 @@ class AutocompleteServiceTest < ActiveSupport::TestCase
           assert_autocomplete_includes("mole_under_eye", "-/mue", :tag_query)
           assert_autocomplete_includes("mole_under_eye", "~/mue", :tag_query)
         end
-
-        should "work for regular tags starting with a /" do
-          create(:tag, name: "jojo_pose", post_count: 100)
-          create(:tag, name: "/jp/", post_count: 50)
-
-          assert_autocomplete_equals(%w[/jp/ jojo_pose], "/", :tag_query)
-          assert_autocomplete_equals(%w[/jp/ jojo_pose], "/j", :tag_query)
-          assert_autocomplete_equals(%w[/jp/ jojo_pose], "/jp", :tag_query)
-          assert_autocomplete_equals(%w[/jp/], "/jp/", :tag_query)
-        end
       end
 
       should "autocomplete tags from wiki and artist other names" do

test/unit/tag_test.rb

@@ -169,6 +169,13 @@ class TagTest < ActiveSupport::TestCase
       should_not allow_value("___").for(:name).on(:create)
       should_not allow_value("~foo").for(:name).on(:create)
       should_not allow_value("-foo").for(:name).on(:create)
+      should_not allow_value("/foo").for(:name).on(:create)
+      should_not allow_value("`foo").for(:name).on(:create)
+      should_not allow_value("%foo").for(:name).on(:create)
+      should_not allow_value(")foo").for(:name).on(:create)
+      should_not allow_value("{foo").for(:name).on(:create)
+      should_not allow_value("}foo").for(:name).on(:create)
+      should_not allow_value("]foo").for(:name).on(:create)
       should_not allow_value("_foo").for(:name).on(:create)
       should_not allow_value("foo_").for(:name).on(:create)
       should_not allow_value("foo__bar").for(:name).on(:create)