RecurringTodos::DailyRecurrencePattern#get_next_date refers to 'start' more than self (maybe move it to another class?) Open
return start + 2.day if start.wday == 6 # saturday
return start + 1.day if start.wday == 0 # sunday
return start
else
# if there was no previous todo, do not add n: the first todo starts on
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Feature Envy occurs when a code fragment references another object more often than it references itself, or when several clients do the same series of manipulations on a particular type of object.
Feature Envy reduces the code's ability to communicate intent: code that "belongs" on one class but which is located in another can be hard to find, and may upset the "System of Names" in the host class.
Feature Envy also affects the design's flexibility: A code fragment that is in the wrong class creates couplings that may not be natural within the application's domain, and creates a loss of cohesion in the unwilling host class.
Feature Envy often arises because it must manipulate other objects (usually its arguments) to get them into a useful form, and one force preventing them (the arguments) doing this themselves is that the common knowledge lives outside the arguments, or the arguments are of too basic a type to justify extending that type. Therefore there must be something which 'knows' about the contents or purposes of the arguments. That thing would have to be more than just a basic type, because the basic types are either containers which don't know about their contents, or they are single objects which can't capture their relationship with their fellows of the same type. So, this thing with the extra knowledge should be reified into a class, and the utility method will most likely belong there.
Example
Running Reek on:
class Warehouse
def sale_price(item)
(item.price - item.rebate) * @vat
end
end
would report:
Warehouse#total_price refers to item more than self (FeatureEnvy)
since this:
(item.price - item.rebate)
belongs to the Item class, not the Warehouse.
RecurringTodos::DailyRecurrencePattern#get_next_date has approx 6 statements Open
def get_next_date(previous)
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A method with Too Many Statements
is any method that has a large number of lines.
Too Many Statements
warns about any method that has more than 5 statements. Reek's smell detector for Too Many Statements
counts +1 for every simple statement in a method and +1 for every statement within a control structure (if
, else
, case
, when
, for
, while
, until
, begin
, rescue
) but it doesn't count the control structure itself.
So the following method would score +6 in Reek's statement-counting algorithm:
def parse(arg, argv, &error)
if !(val = arg) and (argv.empty? or /\A-/ =~ (val = argv[0]))
return nil, block, nil # +1
end
opt = (val = parse_arg(val, &error))[1] # +2
val = conv_arg(*val) # +3
if opt and !arg
argv.shift # +4
else
val[0] = nil # +5
end
val # +6
end
(You might argue that the two assigments within the first @if@ should count as statements, and that perhaps the nested assignment should count as +2.)
Complex method RecurringTodos::DailyRecurrencePattern#get_next_date (24.9) Open
def get_next_date(previous)
# previous is the due date of the previous todo or it is the completed_at
# date when the completed_at date is after due_date (i.e. you did not make
# the due date in time)
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Flog calculates the ABC score for methods. The ABC score is based on assignments, branches (method calls), and conditions.
You can read more about ABC metrics or the flog tool
RecurringTodos::DailyRecurrencePattern#get_next_date calls '1.day' 3 times Open
start = determine_start(previous, 1.day)
if only_work_days?
# jump over weekend if necessary
return start + 2.day if start.wday == 6 # saturday
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Duplication occurs when two fragments of code look nearly identical, or when two fragments of code have nearly identical effects at some conceptual level.
Reek implements a check for Duplicate Method Call.
Example
Here's a very much simplified and contrived example. The following method will report a warning:
def double_thing()
@other.thing + @other.thing
end
One quick approach to silence Reek would be to refactor the code thus:
def double_thing()
thing = @other.thing
thing + thing
end
A slightly different approach would be to replace all calls of double_thing
by calls to @other.double_thing
:
class Other
def double_thing()
thing + thing
end
end
The approach you take will depend on balancing other factors in your code.
RecurringTodos::DailyRecurrencePattern#get_next_date calls 'start.wday' 2 times Open
return start + 2.day if start.wday == 6 # saturday
return start + 1.day if start.wday == 0 # sunday
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Duplication occurs when two fragments of code look nearly identical, or when two fragments of code have nearly identical effects at some conceptual level.
Reek implements a check for Duplicate Method Call.
Example
Here's a very much simplified and contrived example. The following method will report a warning:
def double_thing()
@other.thing + @other.thing
end
One quick approach to silence Reek would be to refactor the code thus:
def double_thing()
thing = @other.thing
thing + thing
end
A slightly different approach would be to replace all calls of double_thing
by calls to @other.double_thing
:
class Other
def double_thing()
thing + thing
end
end
The approach you take will depend on balancing other factors in your code.
RecurringTodos::DailyRecurrencePattern has no descriptive comment Open
class DailyRecurrencePattern < AbstractRecurrencePattern
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Classes and modules are the units of reuse and release. It is therefore considered good practice to annotate every class and module with a brief comment outlining its responsibilities.
Example
Given
class Dummy
# Do things...
end
Reek would emit the following warning:
test.rb -- 1 warning:
[1]:Dummy has no descriptive comment (IrresponsibleModule)
Fixing this is simple - just an explaining comment:
# The Dummy class is responsible for ...
class Dummy
# Do things...
end
RecurringTodos::DailyRecurrencePattern#get_next_date performs a nil-check Open
return previous == nil ? start : start + every_x_days.day - 1.day
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A NilCheck
is a type check. Failures of NilCheck
violate the "tell, don't ask" principle.
Additionally, type checks often mask bigger problems in your source code like not using OOP and / or polymorphism when you should.
Example
Given
class Klass
def nil_checker(argument)
if argument.nil?
puts "argument isn't nil!"
end
end
end
Reek would emit the following warning:
test.rb -- 1 warning:
[3]:Klass#nil_checker performs a nil-check. (NilCheck)
Prefer 2.days
. Open
return start + 2.day if start.wday == 6 # saturday
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This cop checks for correct grammar when using ActiveSupport's core extensions to the numeric classes.
Example:
# bad
3.day.ago
1.months.ago
# good
3.days.ago
1.month.ago
Missing magic comment # frozen_string_literal: true
. Open
module RecurringTodos
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This cop is designed to help upgrade to Ruby 3.0. It will add the
comment # frozen_string_literal: true
to the top of files to
enable frozen string literals. Frozen string literals may be default
in Ruby 3.0. The comment will be added below a shebang and encoding
comment. The frozen string literal comment is only valid in Ruby 2.3+.
Example: EnforcedStyle: when_needed (default)
# The `when_needed` style will add the frozen string literal comment
# to files only when the `TargetRubyVersion` is set to 2.3+.
# bad
module Foo
# ...
end
# good
# frozen_string_literal: true
module Foo
# ...
end
Example: EnforcedStyle: always
# The `always` style will always add the frozen string literal comment
# to a file, regardless of the Ruby version or if `freeze` or `<<` are
# called on a string literal.
# bad
module Bar
# ...
end
# good
# frozen_string_literal: true
module Bar
# ...
end
Example: EnforcedStyle: never
# The `never` will enforce that the frozen string literal comment does
# not exist in a file.
# bad
# frozen_string_literal: true
module Baz
# ...
end
# good
module Baz
# ...
end
Prefer the use of the nil?
predicate. Open
return previous == nil ? start : start + every_x_days.day - 1.day
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This cop checks for comparison of something with nil using ==.
Example:
# bad
if x == nil
end
# good
if x.nil?
end
Use a guard clause instead of wrapping the code inside a conditional expression. Open
if only_work_days?
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Use a guard clause instead of wrapping the code inside a conditional expression
Example:
# bad
def test
if something
work
end
end
# good
def test
return unless something
work
end
# also good
def test
work if something
end
# bad
if something
raise 'exception'
else
ok
end
# good
raise 'exception' if something
ok
Don't use parentheses around an unary operation. Open
errors[:base] << "Every other nth day may not be empty for this daily recurrence setting" if (!only_work_days?) && every_x_days.blank?
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This cop checks for redundant parentheses.
Example:
# bad
(x) if ((y.z).nil?)
# good
x if y.z.nil?
Line is too long. [140/120] Open
errors[:base] << "Every other nth day may not be empty for this daily recurrence setting" if (!only_work_days?) && every_x_days.blank?
- Exclude checks
Use start.wday.zero?
instead of start.wday == 0
. Open
return start + 1.day if start.wday == 0 # sunday
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This cop checks for usage of comparison operators (==
,
>
, <
) to test numbers as zero, positive, or negative.
These can be replaced by their respective predicate methods.
The cop can also be configured to do the reverse.
The cop disregards #nonzero?
as it its value is truthy or falsey,
but not true
and false
, and thus not always interchangeable with
!= 0
.
The cop ignores comparisons to global variables, since they are often
populated with objects which can be compared with integers, but are
not themselves Interger
polymorphic.
Example: EnforcedStyle: predicate (default)
# bad
foo == 0
0 > foo
bar.baz > 0
# good
foo.zero?
foo.negative?
bar.baz.positive?
Example: EnforcedStyle: comparison
# bad
foo.zero?
foo.negative?
bar.baz.positive?
# good
foo == 0
0 > foo
bar.baz > 0