Type cast falsy boolean symbols on boolean attribute as false

Before 34cc301f, type casting by boolean attribute when querying is a
no-op, so finding by truthy boolean string (i.e.
`where(value: "true") # => value = 'true'`) didn't work as expected
(matches it to FALSE in MySQL #32624). By type casting is ensured, a
value on boolean attribute is always serialized to TRUE or FALSE.

In PostgreSQL, `where(value: :false) # => value = 'false'` was a valid
SQL, so 34cc301f is a regresson for PostgreSQL since all symbol values
are serialized as TRUE.

I'd say using `:false` is mostly a developer's mistake (user's input
basically comes as a string), but `:false` on boolean attribute is
serialized as TRUE is not a desirable behavior for anybody.

This allows falsy boolean symbols as false, i.e.
`klass.create(value: :false).value? # => false` and
`where(value: :false) # => value = FALSE`.

Fixes #35676.

activemodel/CHANGELOG.md

+*   Type cast falsy boolean symbols on boolean attribute as false.
+
+    Fixes #35676.
+
+    *Ryuta Kamizono*
+
 *   Change how validation error translation strings are fetched: The new behavior
     will first try the more specific keys, including doing locale fallback, then try
     the less specific ones.

activemodel/lib/active_model/type/boolean.rb

@@ -14,7 +14,16 @@ module Type
     # - Empty strings are coerced to +nil+
     # - All other values will be coerced to +true+
     class Boolean < Value
-      FALSE_VALUES = [false, 0, "0", "f", "F", "false", "FALSE", "off", "OFF"].to_set
+      FALSE_VALUES = [
+        false, 0,
+        "0", :"0",
+        "f", :f,
+        "F", :F,
+        "false", :false,
+        "FALSE", :FALSE,
+        "off", :off,
+        "OFF", :OFF,
+      ].to_set.freeze
 
       def type # :nodoc:
         :boolean

activemodel/test/cases/type/boolean_test.rb

@@ -23,6 +23,13 @@ def test_type_cast_boolean
         assert type.cast("\u3000\r\n")
         assert type.cast("\u0000")
         assert type.cast("SOMETHING RANDOM")
+        assert type.cast(:"1")
+        assert type.cast(:t)
+        assert type.cast(:T)
+        assert type.cast(:true)
+        assert type.cast(:TRUE)
+        assert type.cast(:on)
+        assert type.cast(:ON)
 
         # explicitly check for false vs nil
         assert_equal false, type.cast(false)
@@ -34,6 +41,13 @@ def test_type_cast_boolean
         assert_equal false, type.cast("FALSE")
         assert_equal false, type.cast("off")
         assert_equal false, type.cast("OFF")
+        assert_equal false, type.cast(:"0")
+        assert_equal false, type.cast(:f)
+        assert_equal false, type.cast(:F)
+        assert_equal false, type.cast(:false)
+        assert_equal false, type.cast(:FALSE)
+        assert_equal false, type.cast(:off)
+        assert_equal false, type.cast(:OFF)
       end
     end
   end

activerecord/test/cases/boolean_test.rb

@@ -40,4 +40,13 @@ def test_find_by_boolean_string
     assert_equal b_false, Boolean.find_by(value: "false")
     assert_equal b_true, Boolean.find_by(value: "true")
   end
+
+  def test_find_by_falsy_boolean_symbol
+    ActiveModel::Type::Boolean::FALSE_VALUES.each do |value|
+      b_false = Boolean.create!(value: value)
+
+      assert_not_predicate b_false, :value?
+      assert_equal b_false, Boolean.find_by(id: b_false.id, value: value.to_s.to_sym)
+    end
+  end
 end