From 9d5573bbd81640db83e28c4bc33b11b9aa46f4b7 Mon Sep 17 00:00:00 2001
From: Christoph Petschnig <info@purevirtual.de>
Date: Wed, 3 Jun 2009 14:22:48 +0200
Subject: [PATCH] SchemaDumper handles table_prefix/suffix better

---
 activerecord/lib/active_record/schema_dumper.rb    |   18 ++++-
 .../test/cases/schema_dumper_prefix_suffix_test.rb |  100 ++++++++++++++++++++
 2 files changed, 117 insertions(+), 1 deletions(-)
 create mode 100644 activerecord/test/cases/schema_dumper_prefix_suffix_test.rb

diff --git a/activerecord/lib/active_record/schema_dumper.rb b/activerecord/lib/active_record/schema_dumper.rb
index 2d90ef3..b9b415c 100644
--- a/activerecord/lib/active_record/schema_dumper.rb
+++ b/activerecord/lib/active_record/schema_dumper.rb
@@ -15,6 +15,20 @@ module ActiveRecord
     cattr_accessor :ignore_tables 
     @@ignore_tables = []
 
+    ##
+    # :singleton-method:
+    # If set to true, dump only those tables, where table name begins like
+    # ActiveRecord::Base.table_name_prefix. Default is true.
+    cattr_accessor :dump_only_with_prefix
+    @@dump_only_with_prefix = true
+
+    ##
+    # :singleton-method:
+    # Works like +dump_only_with_prefix+, but checks the end of the table names.
+    # Default is true
+    cattr_accessor :dump_only_with_suffix
+    @@dump_only_with_suffix = true
+
     def self.dump(connection=ActiveRecord::Base.connection, stream=STDOUT)
       new(connection).dump(stream)
       stream
@@ -61,7 +75,9 @@ HEADER
 
       def tables(stream)
         @connection.tables.sort.each do |tbl|
-          next if ['schema_migrations', ignore_tables].flatten.any? do |ignored|
+          next if (dump_only_with_prefix && tbl !~ Regexp.new("^#{ActiveRecord::Base.table_name_prefix}")) ||
+              (dump_only_with_suffix && tbl !~ Regexp.new("#{ActiveRecord::Base.table_name_suffix}$"))
+          next if [ActiveRecord::Migrator.schema_migrations_table_name, ignore_tables].flatten.any? do |ignored|
             case ignored
             when String; tbl == ignored
             when Regexp; tbl =~ ignored
diff --git a/activerecord/test/cases/schema_dumper_prefix_suffix_test.rb b/activerecord/test/cases/schema_dumper_prefix_suffix_test.rb
new file mode 100644
index 0000000..2567720
--- /dev/null
+++ b/activerecord/test/cases/schema_dumper_prefix_suffix_test.rb
@@ -0,0 +1,100 @@
+require "cases/helper"
+require 'stringio'
+
+class TableWithPrefixAndSuffix < ActiveRecord::Base; end
+
+class SchemaDumperPrefixSuffixTest < ActiveRecord::TestCase
+
+  OTHER_TABLES = %w(prefix_attached_on_table_name table_with_suffix unmatched_table_name)
+
+  def setup
+    # other tests should not be affected
+    @last_prefix = ActiveRecord::Base.table_name_prefix
+    @last_suffix = ActiveRecord::Base.table_name_suffix
+
+    ActiveRecord::Base.table_name_prefix = 'prefix_'
+    ActiveRecord::Base.table_name_suffix = '_suffix'
+
+    # calling table name will pin down the name of the class' db table
+    TableWithPrefixAndSuffix.table_name
+
+    # create other tables that do not match prefix, suffix or both of them
+    OTHER_TABLES.each do |table_name|
+      ActiveRecord::Base.connection.create_table(table_name) do |t|
+        t.column :foo, :int
+      end
+    end
+
+    # create the pre- and suffixed table
+    ActiveRecord::Base.connection.create_table(TableWithPrefixAndSuffix.table_name) do |t|
+      t.column :foo, :int
+    end
+    
+  end
+
+  def teardown
+    ActiveRecord::Base.connection.drop_table(TableWithPrefixAndSuffix.table_name)
+
+    OTHER_TABLES.each do |table_name|
+      ActiveRecord::Base.connection.drop_table(table_name)
+    end
+
+    # restore previous settings
+    ActiveRecord::Base.table_name_prefix = @last_prefix
+    ActiveRecord::Base.table_name_suffix = @last_suffix
+  end
+  
+  def standard_dump(ignore_tables = [])
+    stream = StringIO.new
+    ActiveRecord::SchemaDumper.ignore_tables = ignore_tables
+    ActiveRecord::SchemaDumper.dump(ActiveRecord::Base.connection, stream)
+    stream.string
+  end
+
+  def test_dump_only_pre_and_suffixed
+    ActiveRecord::SchemaDumper.dump_only_with_prefix = true
+    ActiveRecord::SchemaDumper.dump_only_with_suffix = true
+
+    output = standard_dump
+    assert_match %r{create_table "prefix_table_with_prefix_and_suffixes_suffix"}, output
+    assert output.scan(/create_table/).count == 1
+  end
+
+  def test_dump_only_prefixed
+    ActiveRecord::SchemaDumper.dump_only_with_prefix = true
+    ActiveRecord::SchemaDumper.dump_only_with_suffix = false
+
+    output = standard_dump
+    assert_match %r{create_table "prefix_table_with_prefix_and_suffixes_suffix"}, output
+    # at least two tables must get dumped
+    assert output.scan(/create_table/).count >= 2
+  end
+
+  def test_dump_only_suffixed
+    ActiveRecord::SchemaDumper.dump_only_with_prefix = false
+    ActiveRecord::SchemaDumper.dump_only_with_suffix = true
+
+    output = standard_dump
+    assert_match %r{create_table "prefix_table_with_prefix_and_suffixes_suffix"}, output
+    # at least two tables must get dumped
+    assert output.scan(/create_table/).count >= 2
+  end
+
+  # assert that turning off both flags will dump everything except
+  # ignore_tables and schema_migrations
+  def test_dump_all_with_ignore_tables
+    ActiveRecord::SchemaDumper.dump_only_with_prefix = false
+    ActiveRecord::SchemaDumper.dump_only_with_suffix = false
+
+    output = standard_dump
+    assert_match %r{create_table "prefix_table_with_prefix_and_suffixes_suffix"}, output
+    # at least four tables must get dumped
+    assert output.scan(/create_table/).count >= 4
+
+    # check, if ignore_tables is still working
+    output = standard_dump([/attached_on/])
+    assert_no_match %r{create_table "prefix_attached_on_table_name"}, output
+
+    ActiveRecord::SchemaDumper.ignore_tables = []
+  end
+end
-- 
1.5.6.3