From 059a9194badec4e9c36e8fcb7fea458eea243bb0 Mon Sep 17 00:00:00 2001
From: =?utf8?q?David=20=E2=80=98Bombe=E2=80=99=20Roden?=
 <bombe@pterodactylus.net>
Date: Mon, 29 May 2017 06:53:37 +0200
Subject: [PATCH] Add paginate() extension method and pagination matcher

---
 .../net/pterodactylus/sone/utils/Pagination.kt     |  2 +
 .../pterodactylus/sone/test/PaginationMatcher.kt   | 46 ++++++++++++++++++++++
 .../net/pterodactylus/sone/utils/PaginationTest.kt |  7 ++++
 3 files changed, 55 insertions(+)
 create mode 100644 src/test/kotlin/net/pterodactylus/sone/test/PaginationMatcher.kt

diff --git a/src/main/kotlin/net/pterodactylus/sone/utils/Pagination.kt b/src/main/kotlin/net/pterodactylus/sone/utils/Pagination.kt
index 130fe2e..6c436e2 100644
--- a/src/main/kotlin/net/pterodactylus/sone/utils/Pagination.kt
+++ b/src/main/kotlin/net/pterodactylus/sone/utils/Pagination.kt
@@ -40,3 +40,5 @@ class Pagination<out T>(private val originalItems: List<T>, pageSize: Int): Iter
 	override fun iterator() = items.iterator()
 
 }
+
+fun <T> Iterable<T>.paginate(pageSize: Int) = Pagination<T>(toList(), pageSize)
diff --git a/src/test/kotlin/net/pterodactylus/sone/test/PaginationMatcher.kt b/src/test/kotlin/net/pterodactylus/sone/test/PaginationMatcher.kt
new file mode 100644
index 0000000..5a47ca7
--- /dev/null
+++ b/src/test/kotlin/net/pterodactylus/sone/test/PaginationMatcher.kt
@@ -0,0 +1,46 @@
+package net.pterodactylus.sone.test
+
+import net.pterodactylus.sone.utils.Pagination
+import org.hamcrest.Description
+import org.hamcrest.TypeSafeDiagnosingMatcher
+
+/**
+ * Hamcrest matcher for [Pagination]s.
+ */
+class PaginationMatcher(private val page: Int? = null, private val pages: Int? = null):
+		TypeSafeDiagnosingMatcher<Pagination<*>>() {
+
+	override fun matchesSafely(pagination: Pagination<*>, mismatchDescription: Description): Boolean {
+		page?.let {
+			if (pagination.page != page) {
+				mismatchDescription.appendText("page is ").appendValue(pagination.page)
+				return false
+			}
+		}
+		pages?.let {
+			if (pagination.pageCount != pages) {
+				mismatchDescription.appendText("total pages is ").appendValue(pagination.pageCount)
+				return false
+			}
+		}
+		return true
+	}
+
+	override fun describeTo(description: Description) {
+		page?.also {
+			description.appendText("is on page ").appendValue(page)
+			pages?.also {
+					description.appendText(" of ").appendValue(pages)
+			}
+		} ?: pages?.also {
+			description.appendText("has ").appendValue(pages).appendText(" pages")
+		}
+	}
+
+	fun isOnPage(page: Int) = PaginationMatcher(page = page, pages = pages)
+	fun hasPages(pages: Int) = PaginationMatcher(page = page, pages = pages)
+
+}
+
+fun isOnPage(page: Int) = PaginationMatcher(page = page)
+fun hasPages(pages: Int) = PaginationMatcher(pages = pages)
diff --git a/src/test/kotlin/net/pterodactylus/sone/utils/PaginationTest.kt b/src/test/kotlin/net/pterodactylus/sone/utils/PaginationTest.kt
index 9a1153c..dce14fe 100644
--- a/src/test/kotlin/net/pterodactylus/sone/utils/PaginationTest.kt
+++ b/src/test/kotlin/net/pterodactylus/sone/utils/PaginationTest.kt
@@ -1,5 +1,6 @@
 package net.pterodactylus.sone.utils
 
+import net.pterodactylus.sone.test.hasPages
 import org.hamcrest.MatcherAssert.assertThat
 import org.hamcrest.Matchers.contains
 import org.hamcrest.Matchers.equalTo
@@ -14,6 +15,12 @@ class PaginationTest {
 	private val pagination = Pagination<Int>(items, 2)
 
 	@Test
+	fun `pagination can be created from iterable`() {
+		val pagination = listOf(1, 2, 3, 4, 5).asIterable().paginate(2)
+		assertThat(pagination, hasPages(3).isOnPage(0))
+	}
+
+	@Test
 	fun `new pagination is at page 0`() {
 		assertThat(pagination.page, equalTo(0))
 	}
-- 
2.7.4