Added contracts to throwIf and throwUnless

kotlin-result-coroutines/src/commonMain/kotlin/com/github/michaelbull/result/coroutines/RunSuspendCatching.kt

@@ -0,0 +1,4 @@
+package com.github.michaelbull.result.coroutines
+
+class RunSuspendCatching {
+}

kotlin-result-coroutines/src/jvmTest/kotlin/com/github/michaelbull/result/coroutines/RunSuspendCatchingTest.kt

@@ -0,0 +1,11 @@
+package com.github.michaelbull.result.coroutines
+
+import kotlin.test.Test
+
+class RunSuspendCatchingTest {
+
+    @Test
+    fun propogatesCoroutineCancellation() {
+        val testDispatcher = TestCoroutineDispatcher()
+    }
+}

kotlin-result/src/commonMain/kotlin/com/github/michaelbull/result/ThrowIfUnless.kt

@@ -1,5 +1,8 @@
 package com.github.michaelbull.result
 
+import kotlin.contracts.InvocationKind
+import kotlin.contracts.contract
+
 /**
  * If the [Result] is [Err] and contains a [Throwable], throws the [error][Err.error]
  * if the [predicate] returns true.
@@ -8,8 +11,10 @@ package com.github.michaelbull.result
  */
 public inline fun <V : Any?, E : Throwable> Result<V, E>.throwIf(
     predicate: (E) -> Boolean
-): Result<V, E> =
-    onFailure { e -> if (predicate(e)) throw e }
+): Result<V, E> {
+    contract { callsInPlace(predicate, InvocationKind.AT_MOST_ONCE)  }
+    return onFailure { e -> if (predicate(e)) throw e }
+}
 
 /**
  * If the [Result] is [Err] and contains a [Throwable], throws the [error][Err.error]