Experimental fixes: introduce "add annotation" (KT-22760)

idea/testData/quickfix/experimental/basicFunction.kt

@@ -0,0 +1,15 @@
+// "Add '@MyExperimentalAPI' annotation to 'bar'" "true"
+// COMPILER_ARGUMENTS: -Xuse-experimental=kotlin.Experimental
+// WITH_RUNTIME
+
+@Experimental
+annotation class MyExperimentalAPI
+
+@MyExperimentalAPI
+fun foo() {}
+
+class Bar {
+    fun bar() {
+        foo<caret>()
+    }
+}

idea/testData/quickfix/experimental/basicFunction.kt.after

@@ -0,0 +1,16 @@
+// "Add '@MyExperimentalAPI' annotation to 'bar'" "true"
+// COMPILER_ARGUMENTS: -Xuse-experimental=kotlin.Experimental
+// WITH_RUNTIME
+
+@Experimental
+annotation class MyExperimentalAPI
+
+@MyExperimentalAPI
+fun foo() {}
+
+class Bar {
+    @MyExperimentalAPI
+    fun bar() {
+        foo()
+    }
+}

idea/testData/quickfix/experimental/basicFunctionContainingClass.kt

@@ -0,0 +1,15 @@
+// "Add '@MyExperimentalAPI' annotation to containing class 'Bar'" "true"
+// COMPILER_ARGUMENTS: -Xuse-experimental=kotlin.Experimental
+// WITH_RUNTIME
+
+@Experimental
+annotation class MyExperimentalAPI
+
+@MyExperimentalAPI
+fun foo() {}
+
+class Bar {
+    fun bar() {
+        foo<caret>()
+    }
+}

idea/testData/quickfix/experimental/basicFunctionContainingClass.kt.after

@@ -0,0 +1,16 @@
+// "Add '@MyExperimentalAPI' annotation to containing class 'Bar'" "true"
+// COMPILER_ARGUMENTS: -Xuse-experimental=kotlin.Experimental
+// WITH_RUNTIME
+
+@Experimental
+annotation class MyExperimentalAPI
+
+@MyExperimentalAPI
+fun foo() {}
+
+@MyExperimentalAPI
+class Bar {
+    fun bar() {
+        foo()
+    }
+}

idea/testData/quickfix/experimental/basicFunctionNotApplicable.kt

@@ -0,0 +1,21 @@
+// "Add '@MyExperimentalAPI' annotation to 'bar'" "false"
+// COMPILER_ARGUMENTS: -Xuse-experimental=kotlin.Experimental
+// WITH_RUNTIME
+// ACTION: Add '@MyExperimentalAPI' annotation to containing class 'Bar'
+// ERROR: This declaration is experimental and its usage must be marked with '@MyExperimentalAPI' or '@UseExperimental(MyExperimentalAPI::class)'
+// ERROR: This declaration is experimental and its usage must be marked with '@MyExperimentalAPI' or '@UseExperimental(MyExperimentalAPI::class)'
+
+@Experimental
+@Target(AnnotationTarget.CLASS)
+annotation class MyExperimentalAPI
+
+@MyExperimentalAPI
+class Some {
+    fun foo() {}
+}
+
+class Bar {
+    fun bar() {
+        Some().foo<caret>()
+    }
+}

idea/testData/quickfix/experimental/override.kt

@@ -0,0 +1,18 @@
+// "Add '@MyExperimentalAPI' annotation to containing class 'Derived'" "false"
+// COMPILER_ARGUMENTS: -Xuse-experimental=kotlin.Experimental
+// WITH_RUNTIME
+// ACTION: Add '@MyExperimentalAPI' annotation to 'foo'
+// ERROR: This declaration overrides experimental member of supertype 'Base' and must be annotated with '@MyExperimentalAPI'
+
+@Experimental
+@Target(AnnotationTarget.FUNCTION)
+annotation class MyExperimentalAPI
+
+open class Base {
+    @MyExperimentalAPI
+    open fun foo() {}
+}
+
+class Derived : Base() {
+    override fun foo<caret>() {}
+}