Module: Wgit::Assertable

Included in:
Crawler, Database, Document
Defined in:
lib/wgit/assertable.rb

Overview

Module containing assert methods including type checking which can be used for asserting the integrity of method definitions etc.

Author:

  • Michael Telford

Constant Summary collapse

DEFAULT_TYPE_FAIL_MSG = 
"Expected: %s, Actual: %s"
WRONG_METHOD_MSG = 
"arr must be Enumerable, use a different method"
DEFAULT_DUCK_FAIL_MSG = 
"%s doesn't respond_to? %s"

Instance Method Summary collapse

Instance Method Details

#assert_arr_types(arr, type_or_types, msg = nil) ⇒ Object Also known as: assert_arr_type, arr_type, arr_types

Each object within arr must match one of the types listed in type_or_types or an exception is thrown using msg if provided. type_or_types can be a single Class or an Enumerable of Class objects, Strings and Symbols will not work.

Raises:



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# File 'lib/wgit/assertable.rb', line 31

def assert_arr_types(arr, type_or_types, msg = nil)
    raise WRONG_METHOD_MSG unless arr.respond_to?(:each)
    arr.each do |obj|
        assert_types(obj, type_or_types, msg)
    end
end

#assert_respond_to(obj_or_objs, methods, msg = nil) ⇒ Object Also known as: respond_to

The obj_or_objs must respond_to? all of the given methods or an Exception is raised using msg or a default message. Returns obj_or_objs on sucessful assertion.



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# File 'lib/wgit/assertable.rb', line 41

def assert_respond_to(obj_or_objs, methods, msg = nil)
    if obj_or_objs.respond_to?(:each)
        obj_or_objs.each do |obj|
            _assert_respond_to(obj, methods, msg)
        end
    else
        _assert_respond_to(obj_or_objs, methods, msg)
    end
    obj_or_objs
end

#assert_types(obj, type_or_types, msg = nil) ⇒ Object Also known as: assert_type, type, types

obj.instance_of? must return true for one of the types listed in type_or_types or an exception is thrown using msg if provided. type_or_types can be a single Class or an Enumerable of Class objects, Strings and Symbols will not work.



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# File 'lib/wgit/assertable.rb', line 16

def assert_types(obj, type_or_types, msg = nil)
    msg ||= DEFAULT_TYPE_FAIL_MSG % [type_or_types, obj.class]
    if type_or_types.respond_to?(:any?)
        match = type_or_types.any? { |type| obj.instance_of?(type) }
    else
        match = obj.instance_of?(type_or_types)
    end
    raise msg unless match
    obj
end