Module: ObjectPatch::Operations

Defined in:
lib/object_patch/operations.rb,
lib/object_patch/operations/add.rb,
lib/object_patch/operations/copy.rb,
lib/object_patch/operations/move.rb,
lib/object_patch/operations/test.rb,
lib/object_patch/operations/remove.rb,
lib/object_patch/operations/replace.rb

Overview

These operations take advantage of the fact that Pointer#eval returns the same object (obj.object_id match) and thus any changes made to the extracted object will be reflected in the original deeply nested object.

Defined Under Namespace

Classes: Add, Copy, Move, Remove, Replace, Test

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.add_op(target_obj, key, new_value) ⇒ Object

Add a value at the provided key within the provided object. This will behave differently depending on whether we’re processing a hash or an array as the target destination.

It is important to note that this behaves by adjusting the state of the provided object. It does not return the new object itself!

Parameters:

  • target_obj (Array, Hash) —

    The object that will have the value added.

  • key (Fixnum, String) —

    The index / key where the new value will be inserted.

  • new_value (Object) —

    The value to insert at the specified location.

Returns:

  • (Object) —

    The value that was added.



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# File 'lib/object_patch/operations.rb', line 28

def add_op(target_obj, key, new_value)
  if target_obj.is_a?(Array)
    target_obj.insert(check_array_index(key, target_obj.size), new_value)
  else
    target_obj[key] = new_value
  end
end

.check_array_index(index, array_size) ⇒ Fixnum

Validates that the array index provided falls within the acceptable range or in the event we have received the special ‘-’ index defined in the JSON Pointer RFC we treat it as the last element.

Parameters:

  • index (String, Fixnum) —

    The index value to validate

  • array_size (Fixnum) —

    The size of the array this index will be used within (Used for bounds checking).

Returns:

  • (Fixnum) —

    Valid index

Raises:



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# File 'lib/object_patch/operations.rb', line 44

def check_array_index(index, array_size)
  return -1 if index == "-"
  raise ObjectOperationOnArrayException unless index =~ /\A-?\d+\Z/

  index = index.to_i

  # There is a bug in the IETF tests that require us to allow patches to
  # set a value at the end of the array. The final '<=' should actually be
  # a '<'.
  raise OutOfBoundsException unless (0 <= index && index <= array_size)

  index
end

.rm_op(target_obj, key) ⇒ Object

Remove a hash key or index from the provided object.

It is important to note that this behaves by adjusting the state of the provided object. It does not return the new object itself!

Parameters:

  • target_obj (Array, Hash) —

    The object that will have the value removed.

Returns:

  • (Object) —

    The deleted object.



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# File 'lib/object_patch/operations.rb', line 66

def rm_op(target_obj, key)
  if target_obj.is_a?(Array)
    raise InvalidIndexError unless key =~ /\A\d+\Z/
    target_obj.delete_at(check_array_index(key, target_obj.size))
  else
    raise(MissingTargetException, key) unless target_obj.has_key?(key)
    target_obj.delete(key)
  end
end

Instance Method Details

#add_op(target_obj, key, new_value) ⇒ Object (private)

Add a value at the provided key within the provided object. This will behave differently depending on whether we’re processing a hash or an array as the target destination.

It is important to note that this behaves by adjusting the state of the provided object. It does not return the new object itself!

Parameters:

  • target_obj (Array, Hash) —

    The object that will have the value added.

  • key (Fixnum, String) —

    The index / key where the new value will be inserted.

  • new_value (Object) —

    The value to insert at the specified location.

Returns:

  • (Object) —

    The value that was added.



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# File 'lib/object_patch/operations.rb', line 28

def add_op(target_obj, key, new_value)
  if target_obj.is_a?(Array)
    target_obj.insert(check_array_index(key, target_obj.size), new_value)
  else
    target_obj[key] = new_value
  end
end

#check_array_index(index, array_size) ⇒ Fixnum (private)

Validates that the array index provided falls within the acceptable range or in the event we have received the special ‘-’ index defined in the JSON Pointer RFC we treat it as the last element.

Parameters:

  • index (String, Fixnum) —

    The index value to validate

  • array_size (Fixnum) —

    The size of the array this index will be used within (Used for bounds checking).

Returns:

  • (Fixnum) —

    Valid index

Raises:



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# File 'lib/object_patch/operations.rb', line 44

def check_array_index(index, array_size)
  return -1 if index == "-"
  raise ObjectOperationOnArrayException unless index =~ /\A-?\d+\Z/

  index = index.to_i

  # There is a bug in the IETF tests that require us to allow patches to
  # set a value at the end of the array. The final '<=' should actually be
  # a '<'.
  raise OutOfBoundsException unless (0 <= index && index <= array_size)

  index
end

#rm_op(target_obj, key) ⇒ Object (private)

Remove a hash key or index from the provided object.

It is important to note that this behaves by adjusting the state of the provided object. It does not return the new object itself!

Parameters:

  • target_obj (Array, Hash) —

    The object that will have the value removed.

Returns:

  • (Object) —

    The deleted object.



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# File 'lib/object_patch/operations.rb', line 66

def rm_op(target_obj, key)
  if target_obj.is_a?(Array)
    raise InvalidIndexError unless key =~ /\A\d+\Z/
    target_obj.delete_at(check_array_index(key, target_obj.size))
  else
    raise(MissingTargetException, key) unless target_obj.has_key?(key)
    target_obj.delete(key)
  end
end