Add assume function to abort tests instead of failing them

CHANGELOG.md

@@ -23,6 +23,14 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ### Added
 - Added `doesNotContainKey` assertion for `Map`
+- Added `assume` to support test assumptions. To use, wrap your assertions
+  ```kotlin
+  assume {
+    assertThat(System.getProperty("os.name")).startsWith("Windows")
+  }
+  ```
+  this will cause the test to be skipped instead of failing.
+  Note: This feature only works with opentest4j-compatible testing frameworks like junit5.
 
 ### Fixed
 - Fixed incorrect usage of contains in some kdoc examples

assertk/build.gradle.kts

@@ -64,3 +64,7 @@ kotlin {
         }
     }
 }
+
+tasks.withType<Test>().configureEach {
+    useJUnitPlatform()
+}

assertk/src/jvmMain/kotlin/assertk/assume.kt

@@ -0,0 +1,15 @@
+package assertk
+
+/**
+ * Aborts the test instead of failing it, this gives you a way to skip tests based on a dynamic assertion.
+ *
+ * ```
+ * // only run test on windows
+ * assume {
+ *     assertThat(System.getProperty("os.name")).startsWith("Windows")
+ * }
+ * ```
+ */
+inline fun assume(f: () -> Unit) {
+    AssumptionFailure.run { f() }
+}

assertk/src/jvmMain/kotlin/assertk/failure.kt

@@ -3,6 +3,9 @@
 
 package assertk
 
+import com.willowtreeapps.opentest4k.AssertionFailedError
+import com.willowtreeapps.opentest4k.TestAbortedException
+
 internal actual inline fun failWithNotInStacktrace(error: Throwable): Nothing {
     val filtered = error.stackTrace
         .dropWhile { it.className.startsWith("assertk") }
@@ -16,3 +19,21 @@ internal actual inline fun failWithNotInStacktrace(error: Throwable): Nothing {
 internal actual inline fun Throwable.isFatal(): Boolean =
     // https://github.com/ReactiveX/RxJava/blob/6a44e5d0543a48f1c378dc833a155f3f71333bc2/src/main/java/io/reactivex/exceptions/Exceptions.java#L66
     this is VirtualMachineError || this is ThreadDeath || this is LinkageError
+
+internal object AssumptionFailure : Failure {
+    override fun fail(error: Throwable) {
+        failWithNotInStacktrace(
+            TestAbortedException(
+                buildString {
+                    append("Assumption failed")
+                    error.message?.let { message ->
+                        append(": ")
+                        append(message)
+                    }
+                },
+                // unwrap assertion errors
+                if (error is AssertionFailedError) error.cause else error
+            )
+        )
+    }
+}

assertk/src/jvmTest/kotlin/test/assertk/JVMAssertAllTest.kt

@@ -4,9 +4,9 @@ import assertk.all
 import assertk.assertAll
 import assertk.assertThat
 import assertk.assertions.*
-import org.junit.Test
 import java.util.concurrent.Executors
 import java.util.concurrent.TimeUnit
+import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertFailsWith
 import kotlin.test.assertFalse

assertk/src/jvmTest/kotlin/test/assertk/assertions/AssumeTest.kt

@@ -0,0 +1,43 @@
+package test.assertk.assertions
+
+import assertk.assertThat
+import assertk.assertions.isEqualTo
+import assertk.assertions.isFalse
+import assertk.assertions.isTrue
+import assertk.assume
+import com.willowtreeapps.opentest4k.TestAbortedException
+import test.assertk.runTest
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertFailsWith
+
+class AssumeTest {
+    @Test
+    fun assume_throws_TestAbortedException() {
+        val error = assertFailsWith<TestAbortedException> {
+            assume {
+                assertThat(true).isFalse()
+            }
+        }
+
+        assertEquals("Assumption failed: expected to be false", error.message)
+    }
+
+    @Test
+    fun assume_aborts_instead_of_fails_test() {
+        // this test should be skipped instead of failing
+        assume { assertThat(true).isFalse() }
+    }
+
+    @Test
+    fun assume_does_not_capture_unexpected_exceptions() {
+        assertFailsWith<NullPointerException> {
+            assume { throw NullPointerException() }
+        }
+    }
+
+    @Test
+    fun assume_aborts_when_suspend() = runTest {
+        assume { assertThat(suspend { true }()).isFalse()  }
+    }
+}

assertk/src/jvmTest/kotlin/test/assertk/assertions/JVMResultTest.kt

@@ -2,8 +2,8 @@ package test.assertk.assertions
 
 import assertk.assertThat
 import assertk.assertions.isSuccess
-import org.junit.Test
 import test.assertk.exceptionPackageName
+import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertFailsWith
 import kotlin.test.assertNotNull

assertk/src/jvmTest/kotlin/test/assertk/assertions/OptionalTest.kt

@@ -4,10 +4,10 @@ import assertk.all
 import assertk.assertAll
 import assertk.assertThat
 import assertk.assertions.*
-import org.junit.Test
 import java.time.LocalDate
 import java.time.Month
 import java.util.*
+import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertFailsWith
 

assertk/src/jvmTest/kotlin/test/assertk/assertions/support/JavaNumberTest.kt

@@ -4,9 +4,9 @@ import assertk.assertThat
 import assertk.assertions.isNegative
 import assertk.assertions.isPositive
 import assertk.assertions.isZero
-import org.junit.Test
 import java.math.BigDecimal
 import java.math.BigInteger
+import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertFailsWith