Relax Kotlin contracts for Executable parameters

Since `Executable` is allowed/expected to throw exceptions, the
semantics of being called `EXACTLY_ONCE` are blurry because it might not
be executed entirely when throwing an exception. Since the Kotlin 2.1
compiler emits a warning for these parameters, we're relaxing their
contracts to be called `AT_MOST_ONCE` instead.

Author: marcphilipp

junit-jupiter-api/src/main/kotlin/org/junit/jupiter/api/Assertions.kt

@@ -351,7 +351,7 @@ inline fun <reified T : Throwable> assertThrows(
 @API(status = STABLE, since = "5.11")
 inline fun <R> assertDoesNotThrow(executable: () -> R): R {
     contract {
-        callsInPlace(executable, EXACTLY_ONCE)
+        callsInPlace(executable, AT_MOST_ONCE)
     }
 
     return Assertions.assertDoesNotThrow(evaluateAndWrap(executable))
@@ -374,7 +374,7 @@ inline fun <R> assertDoesNotThrow(
     executable: () -> R
 ): R {
     contract {
-        callsInPlace(executable, EXACTLY_ONCE)
+        callsInPlace(executable, AT_MOST_ONCE)
     }
 
     return assertDoesNotThrow({ message }, executable)
@@ -397,7 +397,7 @@ inline fun <R> assertDoesNotThrow(
     executable: () -> R
 ): R {
     contract {
-        callsInPlace(executable, EXACTLY_ONCE)
+        callsInPlace(executable, AT_MOST_ONCE)
         callsInPlace(message, AT_MOST_ONCE)
     }
 
@@ -411,7 +411,7 @@ inline fun <R> assertDoesNotThrow(
 @PublishedApi
 internal inline fun <R> evaluateAndWrap(executable: () -> R): ThrowingSupplier<R> {
     contract {
-        callsInPlace(executable, EXACTLY_ONCE)
+        callsInPlace(executable, AT_MOST_ONCE)
     }
 
     return try {
@@ -439,7 +439,7 @@ fun <R> assertTimeout(
     executable: () -> R
 ): R {
     contract {
-        callsInPlace(executable, EXACTLY_ONCE)
+        callsInPlace(executable, AT_MOST_ONCE)
     }
 
     return Assertions.assertTimeout(timeout, executable)
@@ -463,7 +463,7 @@ fun <R> assertTimeout(
     executable: () -> R
 ): R {
     contract {
-        callsInPlace(executable, EXACTLY_ONCE)
+        callsInPlace(executable, AT_MOST_ONCE)
     }
 
     return Assertions.assertTimeout(timeout, executable, message)
@@ -487,7 +487,7 @@ fun <R> assertTimeout(
     executable: () -> R
 ): R {
     contract {
-        callsInPlace(executable, EXACTLY_ONCE)
+        callsInPlace(executable, AT_MOST_ONCE)
         callsInPlace(message, AT_MOST_ONCE)
     }
 

jupiter-tests/src/test/kotlin/org/junit/jupiter/api/KotlinAssertTimeoutAssertionsTests.kt

@@ -156,26 +156,26 @@ internal class KotlinAssertTimeoutAssertionsTests {
     }
 
     @Test
-    fun `assertTimeout with value initialization in lambda`() {
-        val value: Int
+    fun `assertTimeout with value assignment in lambda`() {
+        var value = 0
 
         assertTimeout(ofMillis(500)) { value = 10 }
 
         assertEquals(10, value)
     }
 
     @Test
-    fun `assertTimeout with message and value initialization in lambda`() {
-        val value: Int
+    fun `assertTimeout with message and value assignment in lambda`() {
+        var value = 0
 
         assertTimeout(ofMillis(500), "message") { value = 10 }
 
         assertEquals(10, value)
     }
 
     @Test
-    fun `assertTimeout with message supplier and value initialization in lambda`() {
-        val value: Int
+    fun `assertTimeout with message supplier and value assignment in lambda`() {
+        var value = 0
 
         @Suppress("ASSIGNED_BUT_NEVER_ACCESSED_VARIABLE")
         val valueInMessageSupplier: Int