Trailing whitespace detected. Open
content_length_proc: proc { |total|
- Exclude checks
Useless assignment to variable - download
. Open
download = open(url,
- Read upRead up
- Exclude checks
This cop checks for every useless assignment to local variable in every
scope.
The basic idea for this cop was from the warning of ruby -cw
:
assigned but unused variable - foo
Currently this cop has advanced logic that detects unreferenced reassignments and properly handles varied cases such as branch, loop, rescue, ensure, etc.
Example:
# bad
def some_method
some_var = 1
do_something
end
Example:
# good
def some_method
some_var = 1
do_something(some_var)
end
Prefer single-quoted strings when you don't need string interpolation or special symbols. Open
progress_bar = ProgressBar.new("Download", total)
- Read upRead up
- Exclude checks
Checks if uses of quotes match the configured preference.
Example: EnforcedStyle: single_quotes (default)
# bad
"No special symbols"
"No string interpolation"
"Just text"
# good
'No special symbols'
'No string interpolation'
'Just text'
"Wait! What's #{this}!"
Example: EnforcedStyle: double_quotes
# bad
'Just some text'
'No special chars or interpolation'
# good
"Just some text"
"No special chars or interpolation"
"Every string in #{project} uses double_quotes"
Use def with parentheses when there are parameters. Open
def download_episode name, url, path = nil
- Read upRead up
- Exclude checks
This cops checks for parentheses around the arguments in method definitions. Both instance and class/singleton methods are checked.
Example: EnforcedStyle: require_parentheses (default)
# The `require_parentheses` style requires method definitions
# to always use parentheses
# bad
def bar num1, num2
num1 + num2
end
def foo descriptive_var_name,
another_descriptive_var_name,
last_descriptive_var_name
do_something
end
# good
def bar(num1, num2)
num1 + num2
end
def foo(descriptive_var_name,
another_descriptive_var_name,
last_descriptive_var_name)
do_something
end
Example: EnforcedStyle: requirenoparentheses
# The `require_no_parentheses` style requires method definitions
# to never use parentheses
# bad
def bar(num1, num2)
num1 + num2
end
def foo(descriptive_var_name,
another_descriptive_var_name,
last_descriptive_var_name)
do_something
end
# good
def bar num1, num2
num1 + num2
end
def foo descriptive_var_name,
another_descriptive_var_name,
last_descriptive_var_name
do_something
end
Example: EnforcedStyle: requirenoparenthesesexceptmultiline
# The `require_no_parentheses_except_multiline` style prefers no
# parantheses when method definition arguments fit on single line,
# but prefers parantheses when arguments span multiple lines.
# bad
def bar(num1, num2)
num1 + num2
end
def foo descriptive_var_name,
another_descriptive_var_name,
last_descriptive_var_name
do_something
end
# good
def bar num1, num2
num1 + num2
end
def foo(descriptive_var_name,
another_descriptive_var_name,
last_descriptive_var_name)
do_something
end
Trailing whitespace detected. Open
- Exclude checks
Missing top-level class documentation comment. Open
class Freakonomics::Downloader
- Read upRead up
- Exclude checks
This cop checks for missing top-level documentation of classes and modules. Classes with no body are exempt from the check and so are namespace modules - modules that have nothing in their bodies except classes, other modules, or constant definitions.
The documentation requirement is annulled if the class or module has a "#:nodoc:" comment next to it. Likewise, "#:nodoc: all" does the same for all its children.
Example:
# bad
class Person
# ...
end
# good
# Description/Explanation of Person class
class Person
# ...
end
Align )
with (
. Open
)
- Read upRead up
- Exclude checks
This cops checks the indentation of hanging closing parentheses in
method calls, method definitions, and grouped expressions. A hanging
closing parenthesis means )
preceded by a line break.
Example:
# good: when x is on its own line, indent this way
func(
x,
y
)
# good: when x follows opening parenthesis, align parentheses
a = b * (x +
y
)
# bad
def func(
x,
y
)
end
Use def with parentheses when there are parameters. Open
def self.download name, url
- Read upRead up
- Exclude checks
This cops checks for parentheses around the arguments in method definitions. Both instance and class/singleton methods are checked.
Example: EnforcedStyle: require_parentheses (default)
# The `require_parentheses` style requires method definitions
# to always use parentheses
# bad
def bar num1, num2
num1 + num2
end
def foo descriptive_var_name,
another_descriptive_var_name,
last_descriptive_var_name
do_something
end
# good
def bar(num1, num2)
num1 + num2
end
def foo(descriptive_var_name,
another_descriptive_var_name,
last_descriptive_var_name)
do_something
end
Example: EnforcedStyle: requirenoparentheses
# The `require_no_parentheses` style requires method definitions
# to never use parentheses
# bad
def bar(num1, num2)
num1 + num2
end
def foo(descriptive_var_name,
another_descriptive_var_name,
last_descriptive_var_name)
do_something
end
# good
def bar num1, num2
num1 + num2
end
def foo descriptive_var_name,
another_descriptive_var_name,
last_descriptive_var_name
do_something
end
Example: EnforcedStyle: requirenoparenthesesexceptmultiline
# The `require_no_parentheses_except_multiline` style prefers no
# parantheses when method definition arguments fit on single line,
# but prefers parantheses when arguments span multiple lines.
# bad
def bar(num1, num2)
num1 + num2
end
def foo descriptive_var_name,
another_descriptive_var_name,
last_descriptive_var_name
do_something
end
# good
def bar num1, num2
num1 + num2
end
def foo(descriptive_var_name,
another_descriptive_var_name,
last_descriptive_var_name)
do_something
end
Use def with parentheses when there are parameters. Open
def download name, url
- Read upRead up
- Exclude checks
This cops checks for parentheses around the arguments in method definitions. Both instance and class/singleton methods are checked.
Example: EnforcedStyle: require_parentheses (default)
# The `require_parentheses` style requires method definitions
# to always use parentheses
# bad
def bar num1, num2
num1 + num2
end
def foo descriptive_var_name,
another_descriptive_var_name,
last_descriptive_var_name
do_something
end
# good
def bar(num1, num2)
num1 + num2
end
def foo(descriptive_var_name,
another_descriptive_var_name,
last_descriptive_var_name)
do_something
end
Example: EnforcedStyle: requirenoparentheses
# The `require_no_parentheses` style requires method definitions
# to never use parentheses
# bad
def bar(num1, num2)
num1 + num2
end
def foo(descriptive_var_name,
another_descriptive_var_name,
last_descriptive_var_name)
do_something
end
# good
def bar num1, num2
num1 + num2
end
def foo descriptive_var_name,
another_descriptive_var_name,
last_descriptive_var_name
do_something
end
Example: EnforcedStyle: requirenoparenthesesexceptmultiline
# The `require_no_parentheses_except_multiline` style prefers no
# parantheses when method definition arguments fit on single line,
# but prefers parantheses when arguments span multiple lines.
# bad
def bar(num1, num2)
num1 + num2
end
def foo descriptive_var_name,
another_descriptive_var_name,
last_descriptive_var_name
do_something
end
# good
def bar num1, num2
num1 + num2
end
def foo(descriptive_var_name,
another_descriptive_var_name,
last_descriptive_var_name)
do_something
end
Use nested module/class definitions instead of compact style. Open
class Freakonomics::Downloader
- Read upRead up
- Exclude checks
This cop checks the style of children definitions at classes and modules. Basically there are two different styles:
Example: EnforcedStyle: nested (default)
# good
# have each child on its own line
class Foo
class Bar
end
end
Example: EnforcedStyle: compact
# good
# combine definitions as much as possible
class Foo::Bar
end
The compact style is only forced for classes/modules with one child.
Align the parameters of a method call if they span more than one line. Open
content_length_proc: proc { |total|
progress_bar = ProgressBar.new("Download", total)
},
progress_proc: proc { |step|
progress_bar.set(step)
- Read upRead up
- Exclude checks
Here we check if the parameters on a multi-line method call or definition are aligned.
Example: EnforcedStyle: withfirstparameter (default)
# good
foo :bar,
:baz
# bad
foo :bar,
:baz
Example: EnforcedStyle: withfixedindentation
# good
foo :bar,
:baz
# bad
foo :bar,
:baz
Extra empty line detected at method body end. Open
end
- Read upRead up
- Exclude checks
This cops checks if empty lines exist around the bodies of methods.
Example:
# good
def foo
# ...
end
# bad
def bar
# ...
end
Unused method argument - path
. If it's necessary, use _
or _path
as an argument name to indicate that it won't be used. Open
def download_episode name, url, path = nil
- Read upRead up
- Exclude checks
This cop checks for unused method arguments.
Example:
# bad
def some_method(used, unused, _unused_but_allowed)
puts used
end
Example:
# good
def some_method(used, _unused, _unused_but_allowed)
puts used
end
Unused method argument - name
. If it's necessary, use _
or _name
as an argument name to indicate that it won't be used. Open
def download_episode name, url, path = nil
- Read upRead up
- Exclude checks
This cop checks for unused method arguments.
Example:
# bad
def some_method(used, unused, _unused_but_allowed)
puts used
end
Example:
# good
def some_method(used, _unused, _unused_but_allowed)
puts used
end