cyberark/conjur-api-ruby

An Uncommunicative Variable Name is a variable name that doesn't communicate its intent well enough.

Poor names make it hard for the reader to build a mental picture of what's going on in the code. They can also be mis-interpreted; and they hurt the flow of reading, because the reader must slow down to interpret the names.

An Uncommunicative Variable Name is a variable name that doesn't communicate its intent well enough.

Poor names make it hard for the reader to build a mental picture of what's going on in the code. They can also be mis-interpreted; and they hurt the flow of reading, because the reader must slow down to interpret the names.

An Uncommunicative Variable Name is a variable name that doesn't communicate its intent well enough.

Poor names make it hard for the reader to build a mental picture of what's going on in the code. They can also be mis-interpreted; and they hurt the flow of reading, because the reader must slow down to interpret the names.

An Uncommunicative Variable Name is a variable name that doesn't communicate its intent well enough.

Poor names make it hard for the reader to build a mental picture of what's going on in the code. They can also be mis-interpreted; and they hurt the flow of reading, because the reader must slow down to interpret the names.

An Uncommunicative Variable Name is a variable name that doesn't communicate its intent well enough.

Poor names make it hard for the reader to build a mental picture of what's going on in the code. They can also be mis-interpreted; and they hurt the flow of reading, because the reader must slow down to interpret the names.

This cop looks for use of the same name as outer local variables for block arguments or block local variables. This is a mimic of the warning "shadowing outer local variable - foo" from ruby -cw.

Example:

# bad

def some_method
  foo = 1

  2.times do |foo| # shadowing outer `foo`
    do_something(foo)
  end
end

Example:

# good

def some_method
  foo = 1

  2.times do |bar|
    do_something(bar)
  end
end

This cop makes sure that Ruby source files have snake_case names. Ruby scripts (i.e. source files with a shebang in the first line) are ignored.

The cop also ignores .gemspec files, because Bundler recommends using dashes to separate namespaces in nested gems (i.e. bundler-console becomes Bundler::Console). As such, the gemspec is supposed to be named bundler-console.gemspec.

Example:

# bad
lib/layoutManager.rb

anything/usingCamelCase

# good
lib/layout_manager.rb

anything/using_snake_case.rake

Declare and assign separately to avoid masking return values.

Problematic code:

export foo="$(mycmd)"

Correct code:

foo=$(mycmd)
export foo

Rationale:

In the original code, the return value of mycmd is ignored, and export will instead always return true. This may prevent conditionals, set -e and traps from working correctly.

When first marked for export and assigned separately, the return value of the assignment will be that of mycmd. This avoids the problem.

Exceptions:

If you intend to ignore the return value of an assignment, you can either ignore this warning or use

foo=$(mycmd) || true
export foo

Shellcheck does not warn about export foo=bar because bar is a literal and not a command substitution with an independent return value. It also does not warn about local -r foo=$(cmd), where declaration and assignment must be in the same command.

Notice

Original content from the ShellCheck https://github.com/koalaman/shellcheck/wiki.

Want to escape a single quote? echo 'This is how it'\''s done'.

(Note: in v0.4.6, the error message was accidentally missing the backslash)

Problematic code:

echo 'This is not how it\'s done'.

Correct code:

echo 'This is how it'\''s done'.

Rationale

In POSIX shell, the shell cares about nothing but another single quote to terminate the quoted segment. Not even backslashes are interpreted.

POSIX.1 Shell Command Language § 2.2.2 Single Quotes:

Enclosing characters in single-quotes ( '' ) shall preserve the literal value of each character within the single-quotes. A single-quote cannot occur within single-quotes.

Exceptions

If you want your single quoted string to end in a backslash, you can rewrite as 'string'\\ or [[ignore]] this warning.

Notice

Original content from the ShellCheck https://github.com/koalaman/shellcheck/wiki.

This cop enforces empty line after guard clause

Example:

# bad
def foo
  return if need_return?
  bar
end

# good
def foo
  return if need_return?

  bar
end

# good
def foo
  return if something?
  return if something_different?

  bar
end

# also good
def foo
  if something?
    do_something
    return if need_return?
  end
end

This cop checks for two or more consecutive blank lines.

Example:

# bad - It has two empty lines.
some_method
# one empty line
# two empty lines
some_method

# good
some_method
# one empty line
some_method

This cop makes sure that rescued exceptions variables are named as expected.

The PreferredName config option takes a String. It represents the required name of the variable. Its default is e.

Example: PreferredName: e (default)

# bad
begin
  # do something
rescue MyException => exception
  # do something
end

# good
begin
  # do something
rescue MyException => e
  # do something
end

# good
begin
  # do something
rescue MyException => _e
  # do something
end

Example: PreferredName: exception

# bad
begin
  # do something
rescue MyException => e
  # do something
end

# good
begin
  # do something
rescue MyException => exception
  # do something
end

# good
begin
  # do something
rescue MyException => _exception
  # do something
end

This cop checks for unneeded usages of splat expansion

Example:

# bad

a = *[1, 2, 3]
a = *'a'
a = *1

begin
  foo
rescue *[StandardError, ApplicationError]
  bar
end

case foo
when *[1, 2, 3]
  bar
else
  baz
end

Example:

# good

c = [1, 2, 3]
a = *c
a, b = *c
a, *b = *c
a = *1..10
a = ['a']

begin
  foo
rescue StandardError, ApplicationError
  bar
end

case foo
when 1, 2, 3
  bar
else
  baz
end

This cop makes sure that rescued exceptions variables are named as expected.

The PreferredName config option takes a String. It represents the required name of the variable. Its default is e.

Example: PreferredName: e (default)

# bad
begin
  # do something
rescue MyException => exception
  # do something
end

# good
begin
  # do something
rescue MyException => e
  # do something
end

# good
begin
  # do something
rescue MyException => _e
  # do something
end

Example: PreferredName: exception

# bad
begin
  # do something
rescue MyException => e
  # do something
end

# good
begin
  # do something
rescue MyException => exception
  # do something
end

# good
begin
  # do something
rescue MyException => _exception
  # do something
end

Declare and assign separately to avoid masking return values.

Problematic code:

export foo="$(mycmd)"

Correct code:

foo=$(mycmd)
export foo

Rationale:

In the original code, the return value of mycmd is ignored, and export will instead always return true. This may prevent conditionals, set -e and traps from working correctly.

When first marked for export and assigned separately, the return value of the assignment will be that of mycmd. This avoids the problem.

Exceptions:

If you intend to ignore the return value of an assignment, you can either ignore this warning or use

foo=$(mycmd) || true
export foo

Shellcheck does not warn about export foo=bar because bar is a literal and not a command substitution with an independent return value. It also does not warn about local -r foo=$(cmd), where declaration and assignment must be in the same command.

Notice

Original content from the ShellCheck https://github.com/koalaman/shellcheck/wiki.

This cop checks for string conversion in string interpolation, which is redundant.

Example:

# bad

"result is #{something.to_s}"

Example:

# good

"result is #{something}"

This cop checks whether some constant value isn't a mutable literal (e.g. array or hash).

Strict mode can be used to freeze all constants, rather than just literals. Strict mode is considered an experimental feature. It has not been updated with an exhaustive list of all methods that will produce frozen objects so there is a decent chance of getting some false positives. Luckily, there is no harm in freezing an already frozen object.

Example: EnforcedStyle: literals (default)

# bad
CONST = [1, 2, 3]

# good
CONST = [1, 2, 3].freeze

# good
CONST = <<~TESTING.freeze
  This is a heredoc
TESTING

# good
CONST = Something.new

Example: EnforcedStyle: strict

# bad
CONST = Something.new

# bad
CONST = Struct.new do
  def foo
    puts 1
  end
end

# good
CONST = Something.new.freeze

# good
CONST = Struct.new do
  def foo
    puts 1
  end
end.freeze

This cop enforces empty line after guard clause

Example:

# bad
def foo
  return if need_return?
  bar
end

# good
def foo
  return if need_return?

  bar
end

# good
def foo
  return if something?
  return if something_different?

  bar
end

# also good
def foo
  if something?
    do_something
    return if need_return?
  end
end

This cop checks for usage of the %q/%Q syntax when '' or "" would do.

Example:

# bad
name = %q(Bruce Wayne)
time = %q(8 o'clock)
question = %q("What did you say?")

# good
name = 'Bruce Wayne'
time = "8 o'clock"
question = '"What did you say?"'

This cop enforces empty line after guard clause

Example:

# bad
def foo
  return if need_return?
  bar
end

# good
def foo
  return if need_return?

  bar
end

# good
def foo
  return if something?
  return if something_different?

  bar
end

# also good
def foo
  if something?
    do_something
    return if need_return?
  end
end