Pavel Kirpichenkov
23ed6c4a1f
This commit is a hotfix rather then proper solution.
The source of the issue is that currently type variable fixation result
may change due to fixation order alteration for variables with the same priority.
For instance, having variables V1, V2, and proper types Type1, Type2, such that:
V1 <: Type1
V1 <: V2
Type2 <: V2
both variables will be fixed either to Type1, if V1 will be fixed first,
or to Type2 otherwise.
Since this limitation cannot be easily overcome, the taken approach is to remove
incedental constraint added after 2d5a0546 by restricting nullability constraint check
to `Nothing?` constraints only, thus postponing problematic variable fixation.
To clearify, additional constraint is correct and should cause no harm (in ideal world),
but currently its presence changes fixation order.
So without the restriction the previously used constraint from fixed outer variable
is no longer available by the time problematic variable type is being selected.
^KT-37043 Fixed
Diagnostic tests format specification
Each diagnostic test consists of a single .kt file containing the code of one or several Kotlin or Java source files. Each diagnostic, be it a warning or an error, is marked in the following way:
<!DIAGNOSTIC_FACTORY_NAME!>element<!>
where DIAGNOSTIC_FACTORY_NAME is the name of the diagnostic which is usually one of the constants in one of Errors* classes.
To test not only the presence of the diagnostic but also the arguments which will be rendered to the user, provide string representations of all of them in the parentheses delimited with ; after the diagnostic name:
return <!TYPE_MISMATCH(String; Nothing)!>"OK"<!>
Note: if you're unsure what text should be added for the parameters, just leave the parentheses empty and the failed test will present the actual values in the assertion message.
Directives
Several directives can be added to the beginning of a test file with the following syntax:
// !DIRECTIVE
1. DIAGNOSTICS
This directive allows to exclude some irrelevant diagnostics (e.g. unused parameter) from a certain test, or to test only a specific set of diagnostics.
The syntax is
'([ + - ! ] DIAGNOSTIC_FACTORY_NAME | ERROR | WARNING | INFO ) +'
where
-
+means 'include'; -
-means 'exclude'; -
!means 'exclude everything but this'.Directives are applied in the order of appearance, i.e.
!FOO +BARmeans include onlyFOOandBAR.
Usage:
// !DIAGNOSTICS: -WARNING +CAST_NEVER_SUCCEEDS
// !DIAGNOSTICS: -UNUSED_EXPRESSION -UNUSED_PARAMETER -UNUSED_VARIABLE
2. CHECK_TYPE
The directive adds the following declarations to the file:
fun <T> checkSubtype(t: T) = t
class Inv<T>
fun <E> Inv<E>._() {}
infix fun <T> T.checkType(f: Inv<T>.() -> Unit) {}
With that, an exact type of an expression can be checked in the following way:
fun test(expr: A) {
expr checkType { _<A>() }
}
CHECK_TYPE directive also disables UNDERSCORE_USAGE_WITHOUT_BACKTICKS diagnostics output.
Usage:
// !CHECK_TYPE
3. FILE
The directive lets you compose a test consisting of several files in one actual file.
Usage:
// FILE: A.java
/* Java code */
// FILE: B.kt
/* Kotlin code */
4. LANGUAGE
This directive lets you enable or disable certain language features. Language features are named as enum entries of the class LanguageFeature.
Each feature can be enabled with +, disabled with -, or enabled with warning with warn:.
Usage:
// !LANGUAGE: -TopLevelSealedInheritance
// !LANGUAGE: +TypeAliases -LocalDelegatedProperties
// !LANGUAGE: warn:Coroutines
5. API_VERSION
This directive emulates the behavior of the -api-version command line option, disallowing to use declarations annotated with @SinceKotlin(X) where X is greater than the specified API version.
Note that if this directive is present, the NEWER_VERSION_IN_SINCE_KOTLIN diagnostic is automatically disabled, unless the "!DIAGNOSTICS" directive is present.
Usage:
// !API_VERSION: 1.0
6. RENDER_DIAGNOSTICS_MESSAGES
This directive forces Diagnostic printer prints parametrized diagnostics with all parameters.
Usage:
// !RENDER_DIAGNOSTICS_MESSAGES