Merge pull request #23040 from rafaelfranca/or-error-message

Improve error message for #or when it is structurally incompatible

2 files changed, 11 insertions, 7 deletions

diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb
index 5635b4215b..716b1e8505 100644
--- a/activerecord/lib/active_record/relation/query_methods.rb
+++ b/activerecord/lib/active_record/relation/query_methods.rb
@@ -659,8 +659,10 @@ module ActiveRecord
     end
 
     def or!(other) # :nodoc:
-      unless structurally_compatible_for_or?(other)
-        raise ArgumentError, 'Relation passed to #or must be structurally compatible'
+      incompatible_values = structurally_incompatible_values_for_or(other)
+
+      unless incompatible_values.empty?
+        raise ArgumentError, "Relation passed to #or must be structurally compatible. Incompatible values: #{incompatible_values}"
       end
 
       self.where_clause = self.where_clause.or(other.where_clause)
@@ -1189,10 +1191,10 @@ module ActiveRecord
       end
     end
 
-    def structurally_compatible_for_or?(other)
-      Relation::SINGLE_VALUE_METHODS.all? { |m| send("#{m}_value") == other.send("#{m}_value") } &&
-        (Relation::MULTI_VALUE_METHODS - [:extending]).all? { |m| send("#{m}_values") == other.send("#{m}_values") } &&
-        (Relation::CLAUSE_METHODS - [:having, :where]).all? { |m| send("#{m}_clause") == other.send("#{m}_clause") }
+    def structurally_incompatible_values_for_or(other)
+      Relation::SINGLE_VALUE_METHODS.reject { |m| send("#{m}_value") == other.send("#{m}_value") } +
+        (Relation::MULTI_VALUE_METHODS - [:extending]).reject { |m| send("#{m}_values") == other.send("#{m}_values") } +
+        (Relation::CLAUSE_METHODS - [:having, :where]).reject { |m| send("#{m}_clause") == other.send("#{m}_clause") }
     end
 
     def new_where_clause
diff --git a/activerecord/test/cases/relation/or_test.rb b/activerecord/test/cases/relation/or_test.rb
index 2006fc9611..28a0862f91 100644
--- a/activerecord/test/cases/relation/or_test.rb
+++ b/activerecord/test/cases/relation/or_test.rb
@@ -52,9 +52,11 @@ module ActiveRecord
     end
 
     def test_or_with_incompatible_relations
-      assert_raises ArgumentError do
+      error = assert_raises ArgumentError do
         Post.order('body asc').where('id = 1').or(Post.order('id desc').where(:id => [2, 3])).to_a
       end
+
+      assert_equal "Relation passed to #or must be structurally compatible. Incompatible values: [:order]", error.message
     end
 
     def test_or_when_grouping