1 files changed, 138 insertions, 0 deletions
diff --git a/activemodel/test/cases/attribute_assignment_test.rb b/activemodel/test/cases/attribute_assignment_test.rb
new file mode 100644
index 0000000000..30e8419685
--- /dev/null
+++ b/activemodel/test/cases/attribute_assignment_test.rb
@@ -0,0 +1,138 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+require "active_support/core_ext/hash/indifferent_access"
+require "active_support/hash_with_indifferent_access"
+
+class AttributeAssignmentTest < ActiveModel::TestCase
+  class Model
+    include ActiveModel::AttributeAssignment
+
+    attr_accessor :name, :description
+
+    def initialize(attributes = {})
+      assign_attributes(attributes)
+    end
+
+    def broken_attribute=(value)
+      raise ErrorFromAttributeWriter
+    end
+
+    private
+      attr_writer :metadata
+  end
+
+  class ErrorFromAttributeWriter < StandardError
+  end
+
+  class ProtectedParams
+    attr_accessor :permitted
+    alias :permitted? :permitted
+
+    delegate :keys, :key?, :has_key?, :empty?, to: :@parameters
+
+    def initialize(attributes)
+      @parameters = attributes.with_indifferent_access
+      @permitted = false
+    end
+
+    def permit!
+      @permitted = true
+      self
+    end
+
+    def [](key)
+      @parameters[key]
+    end
+
+    def to_h
+      @parameters
+    end
+
+    def stringify_keys
+      dup
+    end
+
+    def dup
+      super.tap do |duplicate|
+        duplicate.instance_variable_set :@permitted, permitted?
+      end
+    end
+  end
+
+  test "simple assignment" do
+    model = Model.new
+
+    model.assign_attributes(name: "hello", description: "world")
+    assert_equal "hello", model.name
+    assert_equal "world", model.description
+  end
+
+  test "simple assignment alias" do
+    model = Model.new
+
+    model.attributes = { name: "hello", description: "world" }
+    assert_equal "hello", model.name
+    assert_equal "world", model.description
+  end
+
+  test "assign non-existing attribute" do
+    model = Model.new
+    error = assert_raises(ActiveModel::UnknownAttributeError) do
+      model.assign_attributes(hz: 1)
+    end
+
+    assert_equal model, error.record
+    assert_equal "hz", error.attribute
+  end
+
+  test "assign private attribute" do
+    model = Model.new
+    assert_raises(ActiveModel::UnknownAttributeError) do
+      model.assign_attributes(metadata: { a: 1 })
+    end
+  end
+
+  test "does not swallow errors raised in an attribute writer" do
+    assert_raises(ErrorFromAttributeWriter) do
+      Model.new(broken_attribute: 1)
+    end
+  end
+
+  test "an ArgumentError is raised if a non-hash-like object is passed" do
+    err = assert_raises(ArgumentError) do
+      Model.new(1)
+    end
+
+    assert_equal("When assigning attributes, you must pass a hash as an argument, Integer passed.", err.message)
+  end
+
+  test "forbidden attributes cannot be used for mass assignment" do
+    params = ProtectedParams.new(name: "Guille", description: "m")
+
+    assert_raises(ActiveModel::ForbiddenAttributesError) do
+      Model.new(params)
+    end
+  end
+
+  test "permitted attributes can be used for mass assignment" do
+    params = ProtectedParams.new(name: "Guille", description: "desc")
+    params.permit!
+    model = Model.new(params)
+
+    assert_equal "Guille", model.name
+    assert_equal "desc", model.description
+  end
+
+  test "regular hash should still be used for mass assignment" do
+    model = Model.new(name: "Guille", description: "m")
+
+    assert_equal "Guille", model.name
+    assert_equal "m", model.description
+  end
+
+  test "assigning no attributes should not raise, even if the hash is un-permitted" do
+    model = Model.new
+    assert_nil model.assign_attributes(ProtectedParams.new({}))
+  end
+end