Allowed passing arrays-of-strings to :join everywhere. Merge duplicate join strings to avoid table aliasing problems.

Signed-off-by: Michael Koziarski <michael@koziarski.com>
[#1077 state:committed]

4 files changed, 68 insertions, 13 deletions

diff --git a/activerecord/lib/active_record/base.rb b/activerecord/lib/active_record/base.rb
index 3aa8e5541d..69ea155ace 100755
--- a/activerecord/lib/active_record/base.rb
+++ b/activerecord/lib/active_record/base.rb
@@ -1576,19 +1576,19 @@ module ActiveRecord #:nodoc:
          (safe_to_array(first) + safe_to_array(second)).uniq
         end
 
-        def merge_joins(first, second)
-          if first.is_a?(String) && second.is_a?(String)
-            "#{first} #{second}"
-          elsif first.is_a?(String) || second.is_a?(String)
-            if first.is_a?(String)
-              join_dependency = ActiveRecord::Associations::ClassMethods::InnerJoinDependency.new(self, second, nil)
-              "#{first} #{join_dependency.join_associations.collect { |assoc| assoc.association_join }.join}"
-            else
-              join_dependency = ActiveRecord::Associations::ClassMethods::InnerJoinDependency.new(self, first, nil)
-              "#{join_dependency.join_associations.collect { |assoc| assoc.association_join }.join} #{second}"
+        def merge_joins(*joins)
+          if joins.any?{|j| j.is_a?(String) || array_of_strings?(j) }
+            joins = joins.collect do |join|
+              join = [join] if join.is_a?(String)
+              unless array_of_strings?(join)
+                join_dependency = ActiveRecord::Associations::ClassMethods::InnerJoinDependency.new(self, join, nil)
+                join = join_dependency.join_associations.collect { |assoc| assoc.association_join }
+              end
+              join
             end
+            joins.flatten.uniq
           else
-            (safe_to_array(first) + safe_to_array(second)).uniq
+            joins.collect{|j| safe_to_array(j)}.flatten.uniq
           end
         end
 
@@ -1604,6 +1604,10 @@ module ActiveRecord #:nodoc:
           end
         end
 
+        def array_of_strings?(o)
+          o.is_a?(Array) && o.all?{|obj| obj.is_a?(String)}
+        end
+
         def add_order!(sql, order, scope = :auto)
           scope = scope(:find) if :auto == scope
           scoped_order = scope[:order] if scope
@@ -1652,8 +1656,12 @@ module ActiveRecord #:nodoc:
           merged_joins = scope && scope[:joins] && joins ? merge_joins(scope[:joins], joins) : (joins || scope && scope[:joins])
           case merged_joins
           when Symbol, Hash, Array
-            join_dependency = ActiveRecord::Associations::ClassMethods::InnerJoinDependency.new(self, merged_joins, nil)
-            sql << " #{join_dependency.join_associations.collect { |assoc| assoc.association_join }.join} "
+            if array_of_strings?(merged_joins)
+              sql << merged_joins.join(' ') + " "
+            else
+              join_dependency = ActiveRecord::Associations::ClassMethods::InnerJoinDependency.new(self, merged_joins, nil)
+              sql << " #{join_dependency.join_associations.collect { |assoc| assoc.association_join }.join} "
+            end
           when String
             sql << " #{merged_joins} "
           end
diff --git a/activerecord/test/cases/finder_test.rb b/activerecord/test/cases/finder_test.rb
index 10f6aa0f2a..292b88edbc 100644
--- a/activerecord/test/cases/finder_test.rb
+++ b/activerecord/test/cases/finder_test.rb
@@ -935,6 +935,17 @@ class FinderTest < ActiveRecord::TestCase
     assert_equal 1, first.id
   end
 
+  def test_joins_with_string_array
+    person_with_reader_and_post = Post.find(
+      :all,
+      :joins => [
+        "INNER JOIN categorizations ON categorizations.post_id = posts.id",
+        "INNER JOIN categories ON categories.id = categorizations.category_id AND categories.type = 'SpecialCategory'"
+      ]
+    )
+    assert_equal 1, person_with_reader_and_post.size
+  end
+
   def test_find_by_id_with_conditions_with_or
     assert_nothing_raised do
       Post.find([1,2,3],
diff --git a/activerecord/test/cases/method_scoping_test.rb b/activerecord/test/cases/method_scoping_test.rb
index af6fcd32ad..ff10bfaf3e 100644
--- a/activerecord/test/cases/method_scoping_test.rb
+++ b/activerecord/test/cases/method_scoping_test.rb
@@ -138,6 +138,36 @@ class MethodScopingTest < ActiveRecord::TestCase
     assert_equal authors(:david).attributes, scoped_authors.first.attributes
   end
 
+  def test_scoped_find_merges_string_array_style_and_string_style_joins
+    scoped_authors = Author.with_scope(:find => { :joins => ["INNER JOIN posts ON posts.author_id = authors.id"]}) do
+      Author.find(:all, :select => 'DISTINCT authors.*', :joins => 'INNER JOIN comments ON posts.id = comments.post_id', :conditions => 'comments.id = 1')
+    end
+    assert scoped_authors.include?(authors(:david))
+    assert !scoped_authors.include?(authors(:mary))
+    assert_equal 1, scoped_authors.size
+    assert_equal authors(:david).attributes, scoped_authors.first.attributes
+  end
+
+  def test_scoped_find_merges_string_array_style_and_hash_style_joins
+    scoped_authors = Author.with_scope(:find => { :joins => :posts}) do
+      Author.find(:all, :select => 'DISTINCT authors.*', :joins => ['INNER JOIN comments ON posts.id = comments.post_id'], :conditions => 'comments.id = 1')
+    end
+    assert scoped_authors.include?(authors(:david))
+    assert !scoped_authors.include?(authors(:mary))
+    assert_equal 1, scoped_authors.size
+    assert_equal authors(:david).attributes, scoped_authors.first.attributes
+  end
+
+  def test_scoped_find_merges_joins_and_eliminates_duplicate_string_joins
+    scoped_authors = Author.with_scope(:find => { :joins => 'INNER JOIN posts ON posts.author_id = authors.id'}) do
+      Author.find(:all, :select => 'DISTINCT authors.*', :joins => ["INNER JOIN posts ON posts.author_id = authors.id", "INNER JOIN comments ON posts.id = comments.post_id"], :conditions => 'comments.id = 1')
+    end
+    assert scoped_authors.include?(authors(:david))
+    assert !scoped_authors.include?(authors(:mary))
+    assert_equal 1, scoped_authors.size
+    assert_equal authors(:david).attributes, scoped_authors.first.attributes
+  end
+
   def test_scoped_count_include
     # with the include, will retrieve only developers for the given project
     Developer.with_scope(:find => { :include => :projects }) do
diff --git a/activerecord/test/cases/named_scope_test.rb b/activerecord/test/cases/named_scope_test.rb
index 444debd255..64e899780c 100644
--- a/activerecord/test/cases/named_scope_test.rb
+++ b/activerecord/test/cases/named_scope_test.rb
@@ -271,4 +271,10 @@ class NamedScopeTest < ActiveRecord::TestCase
       topics.size # use loaded (no query)
     end
   end
+
+  def test_chaining_with_duplicate_joins
+    join = "INNER JOIN comments ON comments.post_id = posts.id"
+    post = Post.find(1)
+    assert_equal post.comments.size, Post.scoped(:joins => join).scoped(:joins => join, :conditions => "posts.id = #{post.id}").size
+  end
 end