Add Seq template func

Very similar to GNU's seq.

Fixes #552

Conflicts:
	tpl/template.go

1 files changed, 43 insertions, 0 deletions

diff --git a/helpers/general_test.go b/helpers/general_test.go
index e185fe08c..9d28d214c 100644
--- a/helpers/general_test.go
+++ b/helpers/general_test.go
@@ -133,6 +133,49 @@ func TestMd5StringEmpty(t *testing.T) {
 	}
 }
 
+func TestSeq(t *testing.T) {
+	for i, this := range []struct {
+		in     []interface{}
+		expect interface{}
+	}{
+		{[]interface{}{-2, 5}, []int{-2, -1, 0, 1, 2, 3, 4, 5}},
+		{[]interface{}{1, 2, 4}, []int{1, 3}},
+		{[]interface{}{1}, []int{1}},
+		{[]interface{}{3}, []int{1, 2, 3}},
+		{[]interface{}{3.2}, []int{1, 2, 3}},
+		{[]interface{}{0}, []int{}},
+		{[]interface{}{-1}, []int{-1}},
+		{[]interface{}{-3}, []int{-1, -2, -3}},
+		{[]interface{}{3, -2}, []int{3, 2, 1, 0, -1, -2}},
+		{[]interface{}{6, -2, 2}, []int{6, 4, 2}},
+		{[]interface{}{1, 0, 2}, false},
+		{[]interface{}{1, -1, 2}, false},
+		{[]interface{}{2, 1, 1}, false},
+		{[]interface{}{2, 1, 1, 1}, false},
+		{[]interface{}{2001}, false},
+		{[]interface{}{}, false},
+		{[]interface{}{t}, []int{}},
+		{nil, false},
+	} {
+
+		result, err := Seq(this.in...)
+
+		if b, ok := this.expect.(bool); ok && !b {
+			if err == nil {
+				t.Errorf("[%d] TestSeq didn't return an expected error %s", i)
+			}
+		} else {
+			if err != nil {
+				t.Errorf("[%d] failed: %s", i, err)
+				continue
+			}
+			if !reflect.DeepEqual(result, this.expect) {
+				t.Errorf("[%d] TestSeq got %v but expected %v", i, result, this.expect)
+			}
+		}
+	}
+}
+
 func TestDoArithmetic(t *testing.T) {
 	for i, this := range []struct {
 		a      interface{}