execution/executor_test.go

// Copyright 2019 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

package execution

import (
	"bytes"
	"context"
	"errors"
	"io"
	"os/exec"
	"testing"

	"github.com/google/go-cmp/cmp"
)

func TestExecAll(t *testing.T) {
	echo, err := exec.LookPath("echo")
	if err != nil {
		t.Fatal(err)
	}

	helloCmd := Command{Args: []string{echo, "hello"}}
	byeCmd := Command{Args: []string{echo, "bye"}}
	unknownCmd := Command{Args: []string{"unknownCmd"}}
	userCmd := Command{Args: []string{"false"}, UserCausedError: true}
	tests := []struct {
		name           string
		cmds           []Command
		expectErr      bool
		expectUserErr  bool
		expectedStdout string
	}{
		{
			name:           "all pass",
			cmds:           []Command{helloCmd, byeCmd},
			expectedStdout: "hello\nbye\n",
		},
		{
			name:           "middle command fails",
			cmds:           []Command{helloCmd, unknownCmd, byeCmd},
			expectErr:      true,
			expectedStdout: "hello\n",
		},
		{
			name:           "last command fails",
			cmds:           []Command{helloCmd, byeCmd, unknownCmd},
			expectErr:      true,
			expectedStdout: "hello\nbye\n",
		},
		{
			name:          "user command fails",
			cmds:          []Command{userCmd},
			expectErr:     true,
			expectUserErr: true,
		},
	}

	for _, test := range tests {
		t.Run(test.name, func(t *testing.T) {
			ctx := context.Background()
			var stdout bytes.Buffer
			executor := NewExecutor(&stdout, io.Discard, "")
			if err := executor.ExecAll(ctx, test.cmds); err != nil {
				if !test.expectErr {
					t.Errorf("Failed with error: %s", err)
				}
				var userErr userError
				if errors.As(err, &userErr) {
					if !test.expectUserErr {
						t.Errorf("Got user error unexpectedly: %s", userErr)
					}
				} else if test.expectUserErr {
					t.Errorf("Got non-user error unexpectedly: %s", err)
				}
			} else if test.expectErr {
				t.Errorf("Expected an error but didn't get one")
			}

			if diff := cmp.Diff(test.expectedStdout, stdout.String()); diff != "" {
				t.Errorf("Unexpected stdout diff: %s", diff)
			}
		})
	}

	t.Run("context canceled", func(t *testing.T) {
		executor := NewExecutor(io.Discard, io.Discard, t.TempDir())
		ctx, cancel := context.WithCancel(context.Background())
		go cancel()
		if err := executor.Exec(ctx, "sleep", "2"); !errors.Is(err, context.Canceled) {
			t.Fatalf("Expected Exec to return context.Canceled after context cancelation but got: %s", err)
		}
	})
}