testable_test.go

package testable

import (
	"errors"
	"strings"
	"testing"

	gloo "github.com/gloo-foo/framework"
	"github.com/gloo-foo/framework/patterns"
)

// upper is a tiny command that upper-cases each input line.
func upper() gloo.Command[[]byte, []byte] {
	return patterns.Map(func(line []byte) ([]byte, error) {
		return []byte(strings.ToUpper(string(line))), nil
	})
}

// failing is a command that fails on the first line.
func failing() gloo.Command[[]byte, []byte] {
	return patterns.Map(func([]byte) ([]byte, error) {
		return nil, errors.New("boom")
	})
}

func TestTest_OutputRetainsTrailingNewline(t *testing.T) {
	out, err := Test(upper(), "hello\nworld\n")
	if err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	if out != "HELLO\nWORLD\n" {
		t.Errorf("Test() = %q, want %q", out, "HELLO\nWORLD\n")
	}
}

func TestTest_PropagatesError(t *testing.T) {
	out, err := Test(failing(), "x\n")
	if err == nil {
		t.Fatalf("expected error, got nil")
	}
	if out != "" {
		t.Errorf("Test() output = %q, want empty on error", out)
	}
}

func TestTestLines_SplitsAndStrips(t *testing.T) {
	lines, err := TestLines(upper(), "a\nb\nc\n")
	if err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	want := []string{"A", "B", "C"}
	if len(lines) != len(want) {
		t.Fatalf("got %d lines, want %d: %v", len(lines), len(want), lines)
	}
	for i := range want {
		if lines[i] != want[i] {
			t.Errorf("line[%d] = %q, want %q", i, lines[i], want[i])
		}
	}
}

func TestTestLines_Empty(t *testing.T) {
	lines, err := TestLines(upper(), "")
	if err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	if len(lines) != 0 {
		t.Errorf("got %d lines, want 0", len(lines))
	}
}

func TestTestLines_PropagatesError(t *testing.T) {
	lines, err := TestLines(failing(), "x\n")
	if err == nil {
		t.Fatalf("expected error, got nil")
	}
	if lines != nil {
		t.Errorf("lines = %v, want nil on error", lines)
	}
}