#110 - Fix Slice bug producing a \n when provided with an empty slice

script.go

@@ -288,6 +288,9 @@ func ListFiles(path string) *Pipe {
 // Slice creates a pipe containing each element of the supplied slice of
 // strings, one per line.
 func Slice(s []string) *Pipe {
+	if len(s) == 0 {
+		return NewPipe()
+	}
 	return Echo(strings.Join(s, "\n") + "\n")
 }
 
@@ -545,9 +548,10 @@ func (p *Pipe) First(n int) *Pipe {
 // easier to read:
 //
 // 10 apple
-//  4 banana
-//  2 orange
-//  1 kumquat
+//
+//	4 banana
+//	2 orange
+//	1 kumquat
 func (p *Pipe) Freq() *Pipe {
 	freq := map[string]int{}
 	type frequency struct {

script_test.go

@@ -1126,6 +1126,18 @@ func TestSliceProducesElementsOfSpecifiedSliceOnePerLine(t *testing.T) {
 	}
 }
 
+func TestSliceGivenEmptySliceProducesEmptyPipe(t *testing.T) {
+	t.Parallel()
+	want := ""
+	got, err := script.Slice([]string{}).String()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !cmp.Equal(want, got) {
+		t.Error(cmp.Diff(want, got))
+	}
+}
+
 func TestStdinReadsFromProgramStandardInput(t *testing.T) {
 	t.Parallel()
 	// dummy test to prove coverage