Write test for ouput types

Taskfile.yml

@@ -13,6 +13,7 @@ vars:
     ./internal/compiler/v2
     ./internal/execext
     ./internal/logger
+    ./internal/output
     ./internal/status
     ./internal/taskfile
     ./internal/taskfile/version

internal/output/output_test.go

@@ -0,0 +1,62 @@
+package output_test
+
+import (
+	"bytes"
+	"fmt"
+	"testing"
+
+	"github.com/go-task/task/internal/output"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestInterleaved(t *testing.T) {
+	var b bytes.Buffer
+	var o output.Output = output.Interleaved{}
+	var w = o.WrapWriter(&b, "")
+
+	fmt.Fprintln(w, "foo\nbar")
+	assert.Equal(t, "foo\nbar\n", b.String())
+	fmt.Fprintln(w, "baz")
+	assert.Equal(t, "foo\nbar\nbaz\n", b.String())
+}
+
+func TestGroup(t *testing.T) {
+	var b bytes.Buffer
+	var o output.Output = output.Group{}
+	var w = o.WrapWriter(&b, "")
+
+	fmt.Fprintln(w, "foo\nbar")
+	assert.Equal(t, "", b.String())
+	fmt.Fprintln(w, "baz")
+	assert.Equal(t, "", b.String())
+	assert.NoError(t, w.Close())
+	assert.Equal(t, "foo\nbar\nbaz\n", b.String())
+}
+
+func TestPrefixed(t *testing.T) {
+	var b bytes.Buffer
+	var o output.Output = output.Prefixed{}
+	var w = o.WrapWriter(&b, "prefix")
+
+	t.Run("simple use cases", func(t *testing.T) {
+		b.Reset()
+
+		fmt.Fprintln(w, "foo\nbar")
+		assert.Equal(t, "[prefix] foo\n[prefix] bar\n", b.String())
+		fmt.Fprintln(w, "baz")
+		assert.Equal(t, "[prefix] foo\n[prefix] bar\n[prefix] baz\n", b.String())
+	})
+
+	t.Run("multiple writes for a single line", func(t *testing.T) {
+		b.Reset()
+
+		for _, char := range []string{"T", "e", "s", "t", "!"} {
+			fmt.Fprint(w, char)
+			assert.Equal(t, "", b.String())
+		}
+
+		assert.NoError(t, w.Close())
+		assert.Equal(t, "[prefix] Test!\n", b.String())
+	})
+}