From 321d50cd8bcd71ad9b6c8a2c63d2335872f9bca7 Mon Sep 17 00:00:00 2001
From: Kevin Jahns <kevin.jahns@protonmail.com>
Date: Sun, 10 Mar 2019 05:23:04 +0100
Subject: [PATCH] (pair) test coverage

---
 dom.js       |  2 +-
 pair.js      | 16 +++++++++-------
 pair.test.js | 18 ++++++++++++++++++
 test.js      |  4 +++-
 4 files changed, 31 insertions(+), 9 deletions(-)
 create mode 100644 pair.test.js

diff --git a/dom.js b/dom.js
index aaadf17..3965868 100644
--- a/dom.js
+++ b/dom.js
@@ -74,7 +74,7 @@ export const removeEventListeners = (node, listeners) => {
 
 /**
  * @param {string} name
- * @param {Array<pair.Pair<string,string>>} attrs Array of key-value pairs
+ * @param {Array<pair.Pair<string,string>|pair.Pair<string,boolean>>} attrs Array of key-value pairs
  * @param {Array<Node>} children
  * @return {Element}
  */
diff --git a/pair.js b/pair.js
index c089dd4..a52d72c 100644
--- a/pair.js
+++ b/pair.js
@@ -1,7 +1,6 @@
 
 /**
- * @template L
- * @template R
+ * @template L,R
  */
 export class Pair {
   /**
@@ -14,21 +13,24 @@ export class Pair {
   }
 }
 
+/**
+ * @template L,R
+ * @param {L} left
+ * @param {R} right
+ * @return {Pair<L,R>}
+ */
 export const create = (left, right) => new Pair(left, right)
 export const createReversed = (right, left) => new Pair(left, right)
 
 /**
- * @template L
- * @template R
+ * @template L,R
  * @param {Array<Pair<L,R>>} arr
  * @param {function(L, R):any} f
  */
 export const forEach = (arr, f) => arr.forEach(p => f(p.left, p.right))
 
 /**
- * @template L
- * @template R
- * @template X
+ * @template L,R,X
  * @param {Array<Pair<L,R>>} arr
  * @param {function(L, R):X} f
  * @return {Array<X>}
diff --git a/pair.test.js b/pair.test.js
new file mode 100644
index 0000000..0179ac4
--- /dev/null
+++ b/pair.test.js
@@ -0,0 +1,18 @@
+import * as t from './testing.js'
+import * as pair from './pair.js'
+import * as math from './math.js'
+
+export const testPair = tc => {
+  const ps = [pair.create(1, 2), pair.create(3, 4), pair.createReversed(6, 5)]
+  t.describe('Counting elements in pair list')
+  let countLeft = 0
+  let countRight = 0
+  pair.forEach(ps, (left, right) => {
+    countLeft += left
+    countRight += right
+  })
+  t.assert(countLeft === 9)
+  t.assert(countRight === 12)
+  t.assert(countLeft === pair.map(ps, left => left).reduce(math.add))
+  t.assert(countRight === pair.map(ps, (left, right) => right).reduce(math.add))
+}
diff --git a/test.js b/test.js
index d4b6a09..80ad944 100644
--- a/test.js
+++ b/test.js
@@ -15,6 +15,7 @@ import * as promise from './promise.test.js'
 import * as map from './map.test.js'
 import * as eventloop from './eventloop.test.js'
 import * as time from './time.test.js'
+import * as pair from './pair.test.js'
 
 import { isBrowser, isNode } from './environment.js'
 
@@ -37,7 +38,8 @@ runTests({
   promise,
   map,
   eventloop,
-  time
+  time,
+  pair
 }).then(success => {
   /* istanbul ignore next */
   if (isNode) {