From 7e77f65003be747157172c10b11a759f55b82429 Mon Sep 17 00:00:00 2001
From: Rob Fletcher <rfletcher@netflix.com>
Date: Tue, 5 Jun 2018 04:40:50 -0700
Subject: [PATCH] Map entry mapping function

Fixes #45
---
 strikt-core/src/main/kotlin/strikt/assertions/Map.kt |  5 ++++-
 strikt-core/src/test/kotlin/strikt/Mapping.kt        | 10 ++++++++++
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/strikt-core/src/main/kotlin/strikt/assertions/Map.kt b/strikt-core/src/main/kotlin/strikt/assertions/Map.kt
index d8ae2467..6f6aed85 100644
--- a/strikt-core/src/main/kotlin/strikt/assertions/Map.kt
+++ b/strikt-core/src/main/kotlin/strikt/assertions/Map.kt
@@ -3,4 +3,7 @@ package strikt.assertions
 import strikt.api.Assertion
 
 fun <T : Map<K, V>, K, V> Assertion<T>.isEmpty() =
-  passesIf("is empty") { isEmpty() }
\ No newline at end of file
+  passesIf("is empty") { isEmpty() }
+
+operator fun <T : Map<K, V>, K, V> Assertion<T>.get(key: K): Assertion<V?> =
+  map("entry [$key] %s") { get(key) }
diff --git a/strikt-core/src/test/kotlin/strikt/Mapping.kt b/strikt-core/src/test/kotlin/strikt/Mapping.kt
index 3fecd2f1..092540ae 100644
--- a/strikt-core/src/test/kotlin/strikt/Mapping.kt
+++ b/strikt-core/src/test/kotlin/strikt/Mapping.kt
@@ -9,6 +9,8 @@ import strikt.assertions.containsExactly
 import strikt.assertions.first
 import strikt.assertions.get
 import strikt.assertions.isEqualTo
+import strikt.assertions.isNotNull
+import strikt.assertions.isNull
 import strikt.assertions.last
 import java.time.LocalDate
 
@@ -37,6 +39,14 @@ internal object Mapping : Spek({
         expect(subject)[1..2].containsExactly("rubberplant", "marzipan")
       }
     }
+
+    describe("mapping assertions on ${Map::class.java.simpleName}") {
+      it("maps to a value element using [key]") {
+        val subject = mapOf("foo" to "bar")
+        expect(subject)["foo"].isNotNull().isEqualTo("bar")
+        expect(subject)["bar"].isNull()
+      }
+    }
   }
 
   describe("custom mapping") {