rspec/rules/S3630/swift/rule.adoc

== Why is this an issue?

Because force casting (``++as!++``) does not perform any type safety validations, it is capable of performing dangerous conversions between unrelated types. When the types are truly unrelated, the cast will cause a system crash.

=== Noncompliant code example

[source,swift]
----
foo as! MyClass  // Noncompliant
----

=== Compliant solution

[source,swift]
----
foo as? MyClass
----

include::../see.adoc[]

ifdef::env-github,rspecator-view[]

'''
== Implementation Specification
(visible only on this page)

=== Message

Replace this force cast with a safer cast.


=== Highlighting

``++as!++``


'''
== Comments And Links
(visible only on this page)

=== on 8 Jul 2016, 20:30:55 Ann Campbell wrote:
http://stackoverflow.com/questions/25708649/downcasting-optionals-in-swift-as-type-or-as-type

include::../comments-and-links.adoc[]

endif::env-github,rspecator-view[]
migrate rule descriptions to new education format 2023-05-03 11:06:20 +02:00			`== Why is this an issue?`

make in-line code blocks verbatim 2021-01-27 13:42:22 +01:00			Because force casting (``++as!++``) does not perform any type safety validations, it is capable of performing dangerous conversions between unrelated types. When the types are truly unrelated, the cast will cause a system crash.
Add rules 3000-3999 2020-06-30 12:48:39 +02:00
migrate rule descriptions to new education format 2023-05-03 11:06:20 +02:00			`=== Noncompliant code example`
Add rules 3000-3999 2020-06-30 12:48:39 +02:00
RULEAPI-661: Add syntax coloring 2022-02-04 17:28:24 +01:00			`[source,swift]`
Add rules 3000-3999 2020-06-30 12:48:39 +02:00			`----`
			`foo as! MyClass // Noncompliant`
			`----`

migrate rule descriptions to new education format 2023-05-03 11:06:20 +02:00			`=== Compliant solution`
Add rules 3000-3999 2020-06-30 12:48:39 +02:00
RULEAPI-661: Add syntax coloring 2022-02-04 17:28:24 +01:00			`[source,swift]`
Add rules 3000-3999 2020-06-30 12:48:39 +02:00			`----`
			`foo as? MyClass`
			`----`

			`include::../see.adoc[]`
Export comments and rspec-to-rspec links from jira 2021-06-02 20:44:38 +02:00
Fix the comment display: rule-id, timestamp, GH visibility, link direction 2021-06-03 09:05:38 +02:00			`ifdef::env-github,rspecator-view[]`
RULEAPI-666: Migrate the "List of parameters", "Highlighting" and "Message" fields from jira RSPEC (#346) 2021-09-20 15:38:42 +02:00
			`'''`
			`== Implementation Specification`
			`(visible only on this page)`

Inline adoc when include has no additional value (#1940) Inline adoc files when they are included exactly once. Also fix language tags because this inlining gives us better information on what language the code is written in. 2023-05-25 14:18:12 +02:00			`=== Message`

			`Replace this force cast with a safer cast.`


			`=== Highlighting`

			``++as!++``
RULEAPI-666: Migrate the "List of parameters", "Highlighting" and "Message" fields from jira RSPEC (#346) 2021-09-20 15:38:42 +02:00

RULEAPI-576: add a horizontal rule between rule description and comments 2021-06-08 15:52:13 +02:00			`'''`
Export comments and rspec-to-rspec links from jira 2021-06-02 20:44:38 +02:00			`== Comments And Links`
			`(visible only on this page)`

Inline adoc when include has no additional value (#1940) Inline adoc files when they are included exactly once. Also fix language tags because this inlining gives us better information on what language the code is written in. 2023-05-25 14:18:12 +02:00			`=== on 8 Jul 2016, 20:30:55 Ann Campbell wrote:`
			`http://stackoverflow.com/questions/25708649/downcasting-optionals-in-swift-as-type-or-as-type`

			`include::../comments-and-links.adoc[]`

Fix the comment display: rule-id, timestamp, GH visibility, link direction 2021-06-03 09:05:38 +02:00			`endif::env-github,rspecator-view[]`