From 8ed06b4d9d0a980d9bfc528314e4d3203e9f4679 Mon Sep 17 00:00:00 2001
From: Drew Bednar <drew@runcible.io>
Date: Sat, 2 Mar 2024 16:01:00 -0500
Subject: [PATCH] Initial array slices

---
 learn_go_with_tests/arrays/go.mod      |  3 ++
 learn_go_with_tests/arrays/sum.go      | 23 ++++++++++++++++
 learn_go_with_tests/arrays/sum_test.go | 38 ++++++++++++++++++++++++++
 3 files changed, 64 insertions(+)
 create mode 100644 learn_go_with_tests/arrays/go.mod
 create mode 100644 learn_go_with_tests/arrays/sum.go
 create mode 100644 learn_go_with_tests/arrays/sum_test.go

diff --git a/learn_go_with_tests/arrays/go.mod b/learn_go_with_tests/arrays/go.mod
new file mode 100644
index 0000000..88bf4e7
--- /dev/null
+++ b/learn_go_with_tests/arrays/go.mod
@@ -0,0 +1,3 @@
+module myarray
+
+go 1.21.0
diff --git a/learn_go_with_tests/arrays/sum.go b/learn_go_with_tests/arrays/sum.go
new file mode 100644
index 0000000..710c016
--- /dev/null
+++ b/learn_go_with_tests/arrays/sum.go
@@ -0,0 +1,23 @@
+package arrays
+
+func Sum(a []int) int {
+	sum := 0
+
+	//aternatively
+	// for i := 0; i < 5; i++ {
+	// 	sum += a[i]
+	// }
+
+	// OR
+
+	// for i := range a {
+	// 	sum += a[i]
+	// }
+
+	// OR
+
+	for _, v := range a {
+		sum += v
+	}
+	return sum
+}
diff --git a/learn_go_with_tests/arrays/sum_test.go b/learn_go_with_tests/arrays/sum_test.go
new file mode 100644
index 0000000..db0aac2
--- /dev/null
+++ b/learn_go_with_tests/arrays/sum_test.go
@@ -0,0 +1,38 @@
+package arrays
+
+import "testing"
+
+// go test -cover will show the test coverage for our package.
+
+func TestSum(t *testing.T) {
+
+	t.Run("sum collection of 5 of integers", func(t *testing.T) {
+		numbers := []int{1, 2, 3, 4, 5}
+
+		got := Sum(numbers)
+		expected := 15
+
+		// https://pkg.go.dev/fmt
+		if got != expected {
+			t.Errorf("got %d expected %d given, %v", got, expected, numbers)
+		}
+	})
+
+	// go test -cover will show the test coverage for our package.
+
+	// You can see that commenting out this "duplicate" function still retains 100%
+	// test coverage, which is how we know it's redundant.
+
+	// t.Run("sum a collection of any size", func(t *testing.T) {
+	// 	numbers := []int{1, 2, 3}
+
+	// 	got := Sum(numbers)
+	// 	expected := 6
+
+	// 	// https://pkg.go.dev/fmt
+	// 	if got != expected {
+	// 		t.Errorf("got %d expected %d given, %v", got, expected, numbers)
+	// 	}
+	// })
+
+}