Extensions to destructure nullable tuples to nullable local variables

fork-handles · Apr 8, 2024 · 9421ed2 · 9421ed2
1 parent 2a47f0c
commit 9421ed2
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Showing 2 changed files with 34 additions and 3 deletions.
diff --git a/tuples4k/build.gradle b/tuples4k/build.gradle
@@ -192,6 +192,21 @@ task generateAsNullableFunctions {
     }
 }
 
+task generateNullableDestructuringExtensions {
+    dependsOn "recreateGeneratedSrcDir"
+
+    doLast {
+        generateSourceFile("nullable-destructuring.kt") { out ->
+            for (n in 2..maxTupleSize) {
+                for (i in 1..n) {
+                    out.println("operator fun <${params(n, "T")}> ${tupleType(n)}?.component$i(): T$i? = this?.component$i()")
+                }
+                out.println()
+            }
+        }
+    }
+}
+
 
 task generateContainsFunctions {
     dependsOn "recreateGeneratedSrcDir"
@@ -216,6 +231,7 @@ task generateSrcMain {
     dependsOn "generatePlusFunctions"
     dependsOn "generateNonNullFunctions"
     dependsOn "generateAsNullableFunctions"
+    dependsOn "generateNullableDestructuringExtensions"
     dependsOn "generateContainsFunctions"
 }
 

diff --git a/tuples4k/src/test/kotlin/dev/forkhandles/tuples/TupleExampleTest.kt b/tuples4k/src/test/kotlin/dev/forkhandles/tuples/TupleExampleTest.kt
@@ -3,8 +3,9 @@ package dev.forkhandles.tuples
 import com.natpryce.hamkrest.absent
 import com.natpryce.hamkrest.assertion.assertThat
 import com.natpryce.hamkrest.equalTo
-import org.junit.jupiter.api.Assertions
-import org.junit.jupiter.api.Assertions.*
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Assertions.assertNull
+import org.junit.jupiter.api.Assertions.assertTrue
 import org.junit.jupiter.api.Test
 
 class TupleExampleTest {
@@ -48,7 +49,7 @@ class TupleExampleTest {
     }
 
     @Test
-    fun `contains`() {
+    fun contains() {
         assertTrue(0 !in tuple(1,2,3))
         assertTrue(1 in tuple(1,2,3))
         assertTrue(2 in tuple(1,2,3))
@@ -58,4 +59,18 @@ class TupleExampleTest {
         assertTrue("x" in tuple("x","y"))
         assertTrue("z" !in tuple("x","y"))
     }
+
+    @Test
+    fun `destructuring nullable tuple`() {
+        @Suppress("RedundantNullableReturnType")
+        val a : Tuple2<String,Int>? = tuple("A", 1)
+        val (a1,a2) = a
+        assertEquals("A", a1)
+        assertEquals(1, a2)
+
+        val b : Tuple2<String,Int>? = null
+        val (b1,b2) = b
+        assertNull(b1)
+        assertNull(b2)
+    }
 }