Showing 240 of 240 total issues
Always use raise
to signal exceptions. Open
fail NotImplementedError, '#fetch must be overridden in the subclass'
- Read upRead up
- Exclude checks
This cop checks for uses of fail
and raise
.
Example: EnforcedStyle: only_raise (default)
# The `only_raise` style enforces the sole use of `raise`.
# bad
begin
fail
rescue Exception
# handle it
end
def watch_out
fail
rescue Exception
# handle it
end
Kernel.fail
# good
begin
raise
rescue Exception
# handle it
end
def watch_out
raise
rescue Exception
# handle it
end
Kernel.raise
Example: EnforcedStyle: only_fail
# The `only_fail` style enforces the sole use of `fail`.
# bad
begin
raise
rescue Exception
# handle it
end
def watch_out
raise
rescue Exception
# handle it
end
Kernel.raise
# good
begin
fail
rescue Exception
# handle it
end
def watch_out
fail
rescue Exception
# handle it
end
Kernel.fail
Example: EnforcedStyle: semantic
# The `semantic` style enforces the use of `fail` to signal an
# exception, then will use `raise` to trigger an offense after
# it has been rescued.
# bad
begin
raise
rescue Exception
# handle it
end
def watch_out
# Error thrown
rescue Exception
fail
end
Kernel.fail
Kernel.raise
# good
begin
fail
rescue Exception
# handle it
end
def watch_out
fail
rescue Exception
raise 'Preferably with descriptive message'
end
explicit_receiver.fail
explicit_receiver.raise
Unused method argument - blk
. If it's necessary, use _
or _blk
as an argument name to indicate that it won't be used. You can also write as get(*)
if you want the method to accept any arguments but don't care about them. Open
def get(key, &blk)
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- 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
Redundant else
-clause. Open
else
- Read upRead up
- Exclude checks
Checks for empty else-clauses, possibly including comments and/or an
explicit nil
depending on the EnforcedStyle.
Example: EnforcedStyle: empty
# warn only on empty else
# bad
if condition
statement
else
end
# good
if condition
statement
else
nil
end
# good
if condition
statement
else
statement
end
# good
if condition
statement
end
Example: EnforcedStyle: nil
# warn on else with nil in it
# bad
if condition
statement
else
nil
end
# good
if condition
statement
else
end
# good
if condition
statement
else
statement
end
# good
if condition
statement
end
Example: EnforcedStyle: both (default)
# warn on empty else and else with nil in it
# bad
if condition
statement
else
nil
end
# bad
if condition
statement
else
end
# good
if condition
statement
else
statement
end
# good
if condition
statement
end
Prefer single-quoted strings when you don't need string interpolation or special symbols. Open
def initialize(dir = "~/.drydock")
- 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"
Prefer to_s
over string interpolation. Open
@parent ? "#{@parent.serial}.#{@parent.children.index(self) + 1}.#{size + 1}" : "#{size + 1}"
- Read upRead up
- Exclude checks
This cop checks for strings that are just an interpolated expression.
Example:
# bad
"#{@var}"
# good
@var.to_s
# good if @var is already a String
@var
Favor modifier if
usage when having a single-line body. Another good alternative is the usage of control flow &&
/||
. Open
if delta_count > 0
- Read upRead up
- Exclude checks
Checks for if and unless statements that would fit on one line
if written as a modifier if/unless. The maximum line length is
configured in the Metrics/LineLength
cop.
Example:
# bad
if condition
do_stuff(bar)
end
unless qux.empty?
Foo.do_something
end
# good
do_stuff(bar) if condition
Foo.do_something unless qux.empty?
Avoid the use of Perl-style backrefs. Open
.gsub(/(?:_)([a-z\d]*)/i) { $1.capitalize }
- Read upRead up
- Exclude checks
This cop looks for uses of Perl-style regexp match backreferences like $1, $2, etc.
Example:
# bad
puts $1
# good
puts Regexp.last_match(1)
Redundant return
detected. Open
return true
- Read upRead up
- Exclude checks
This cop checks for redundant return
expressions.
Example:
def test
return something
end
def test
one
two
three
return something
end
It should be extended to handle methods whose body is if/else or a case expression with a default branch.
Redundant else
-clause. Open
else
- Read upRead up
- Exclude checks
Checks for empty else-clauses, possibly including comments and/or an
explicit nil
depending on the EnforcedStyle.
Example: EnforcedStyle: empty
# warn only on empty else
# bad
if condition
statement
else
end
# good
if condition
statement
else
nil
end
# good
if condition
statement
else
statement
end
# good
if condition
statement
end
Example: EnforcedStyle: nil
# warn on else with nil in it
# bad
if condition
statement
else
nil
end
# good
if condition
statement
else
end
# good
if condition
statement
else
statement
end
# good
if condition
statement
end
Example: EnforcedStyle: both (default)
# warn on empty else and else with nil in it
# bad
if condition
statement
else
nil
end
# bad
if condition
statement
else
end
# good
if condition
statement
else
statement
end
# good
if condition
statement
end
Unused method argument - key
. If it's necessary, use _
or _key
as an argument name to indicate that it won't be used. You can also write as key?(*)
if you want the method to accept any arguments but don't care about them. Open
def key?(key)
- 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 - key
. If it's necessary, use _
or _key
as an argument name to indicate that it won't be used. Open
def set(key, value = nil, &blk)
- 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
Use yield
instead of blk.call
. Open
blk.call
- Read upRead up
- Exclude checks
This cop identifies the use of a &block
parameter and block.call
where yield
would do just as well.
Example:
# bad
def method(&block)
block.call
end
def another(&func)
func.call 1, 2, 3
end
# good
def method
yield
end
def another
yield 1, 2, 3
end
Use yield
instead of blk.call
. Open
blk.call.tap do |contents|
- Read upRead up
- Exclude checks
This cop identifies the use of a &block
parameter and block.call
where yield
would do just as well.
Example:
# bad
def method(&block)
block.call
end
def another(&func)
func.call 1, 2, 3
end
# good
def method
yield
end
def another
yield 1, 2, 3
end
Use yield
instead of blk.call
. Open
blk.call file
- Read upRead up
- Exclude checks
This cop identifies the use of a &block
parameter and block.call
where yield
would do just as well.
Example:
# bad
def method(&block)
block.call
end
def another(&func)
func.call 1, 2, 3
end
# good
def method
yield
end
def another
yield 1, 2, 3
end
Space inside { missing. Open
filters = {dangling: ["true"]}
- Read upRead up
- Exclude checks
Checks that braces used for hash literals have or don't have surrounding space depending on configuration.
Example: EnforcedStyle: space
# The `space` style enforces that hash literals have
# surrounding space.
# bad
h = {a: 1, b: 2}
# good
h = { a: 1, b: 2 }
Example: EnforcedStyle: no_space
# The `no_space` style enforces that hash literals have
# no surrounding space.
# bad
h = { a: 1, b: 2 }
# good
h = {a: 1, b: 2}
Example: EnforcedStyle: compact
# The `compact` style normally requires a space inside
# hash braces, with the exception that successive left
# braces or right braces are collapsed together in nested hashes.
# bad
h = { a: { b: 2 } }
# good
h = { a: { b: 2 }}
Use each_key
instead of keys.each
. Open
my_vols.keys.each do |my_vol|
- Read upRead up
- Exclude checks
This cop checks for uses of each_key
and each_value
Hash methods.
Note: If you have an array of two-element arrays, you can put parentheses around the block arguments to indicate that you're not working with a hash, and suppress RuboCop offenses.
Example:
# bad
hash.keys.each { |k| p k }
hash.values.each { |v| p v }
hash.each { |k, _v| p k }
hash.each { |_k, v| p v }
# good
hash.each_key { |k| p k }
hash.each_value { |v| p v }
Align the parameters of a method call if they span more than one line. Open
"Target path #{target_path.inspect} exists, " +
"but is not a directory in the container"
- 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
Use %i
or %I
for an array of symbols. Open
[:connect_timeout, :read_timeout].each do |key|
- Read upRead up
- Exclude checks
This cop can check for array literals made up of symbols that are not using the %i() syntax.
Alternatively, it checks for symbol arrays using the %i() syntax on projects which do not want to use that syntax.
Configuration option: MinSize
If set, arrays with fewer elements than this value will not trigger the
cop. For example, a MinSize of
3` will not enforce a style on an array
of 2 or fewer elements.
Example: EnforcedStyle: percent (default)
# good
%i[foo bar baz]
# bad
[:foo, :bar, :baz]
Example: EnforcedStyle: brackets
# good
[:foo, :bar, :baz]
# bad
%i[foo bar baz]
Missing top-level class documentation comment. Open
class Base
- 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
Unused method argument - value
. If it's necessary, use _
or _value
as an argument name to indicate that it won't be used. Open
def set(key, value = nil, &blk)
- 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