Merge pull request rails#54064 from Roriz/fix/symbol-proc-on-callbacks

Support symbol proc on callback conditional

Author: byroot

activesupport/lib/active_support/callbacks.rb

@@ -498,9 +498,10 @@ def self.build(filter, callback)
           when Conditionals::Value
             ProcCall.new(filter)
           when ::Proc
-            if filter.arity > 1
+            case filter.arity
+            when 2
               InstanceExec2.new(filter)
-            elsif filter.arity > 0
+            when 1, -2
               InstanceExec1.new(filter)
             else
               InstanceExec0.new(filter)

activesupport/test/callbacks_test.rb

@@ -189,6 +189,8 @@ class ConditionalPerson < Record
     before_save Proc.new { |r| r.history << "b00m" }, if: Proc.new { |r| false }
     before_save Proc.new { |r| r.history << [:before_save, :proc] }, unless: Proc.new { |r| false }
     before_save Proc.new { |r| r.history << "b00m" }, unless: Proc.new { |r| true }
+    before_save Proc.new { |r| r.history << "b00m" }, unless: proc(&:history)
+    before_save Proc.new { |r| r.history << "b00m" }, unless: lambda(&:history)
     # symbol
     before_save Proc.new { |r| r.history << [:before_save, :symbol] }, if: :yes
     before_save Proc.new { |r| r.history << "b00m" }, if: :no