rspec/rules/S1871/swift/rule.adoc
2021-01-27 13:42:22 +01:00

68 lines
1.9 KiB
Plaintext

Having two ``++cases++`` in the same ``++switch++`` statement or branches in the same ``++if++`` structure with the same implementation is at best duplicate code, and at worst a coding error. If the same logic is truly needed for both instances, then they should be combined.
== Noncompliant Code Example
----
switch i {
case 1:
doFirstThing()
doSomething()
case 2:
doSomethingDifferent()
case 3: // Noncompliant; duplicates case 1's implementation
doFirstThing()
doSomething()
default:
doTheRest()
}
if a >= 0 && a < 10 {
doFirstThing()
doTheThing()
} else if a >= 10 && a < 20 {
doTheOtherThing()
} else if a >= 20 && a < 50 {
doFirstThing() // Noncompliant; duplicates first condition
doTheThing()
} else {
doTheRest()
}
----
== Exceptions
``++case++`` labels that declare variables cannot have multiple patterns. Therefore this situation is ignored.
----
switch a {
case .STR_CASE(let x):
print(x)
case .INT_CASE(let x):
print(x)
default:
print("default")
}
----
Blocks in an ``++if++`` chain that contain a single line of code are ignored, as are blocks in a ``++switch++`` statement that contain a single line of code with or without a following ``++break++``.
----
if a >= 0 && a < 10 { //no issue, usually this is done on purpose to increase the readability
doTheThing()
} else if a >= 10 && a < 20 {
doTheThing()
} else if a >= 20 && a < 50 {
doFirstThing()
}
----
But this exception does not apply to ``++if++`` chains without ``++else++``-s, or to ``++switch++``-es without default clauses when all branches have the same single line of code. In case of ``++if++`` chains with ``++else++``-s, or of ``++switch++``-es with default clauses, rule S3923 raises a bug.
----
if a >= 0 && a < 10 { //Noncompliant, this might have been done on purpose but probably not
doTheThing()
} else if a >= 10 && a < 20 {
doTheThing()
}
----