add test for logs

Signed-off-by: Jamie Hannaford <jamie@limetree.org>

cli/command/container/client_test.go

@@ -20,6 +20,7 @@ type fakeClient struct {
 	infoFunc              func() (types.Info, error)
 	containerStatPathFunc func(container, path string) (types.ContainerPathStat, error)
 	containerCopyFromFunc func(container, srcPath string) (io.ReadCloser, types.ContainerPathStat, error)
+	logFunc               func(string, types.ContainerLogsOptions) (io.ReadCloser, error)
 }
 
 func (f *fakeClient) ContainerInspect(_ context.Context, containerID string) (types.ContainerJSON, error) {
@@ -87,3 +88,10 @@ func (f *fakeClient) CopyFromContainer(_ context.Context, container, srcPath str
 	}
 	return nil, types.ContainerPathStat{}, nil
 }
+
+func (f *fakeClient) ContainerLogs(_ context.Context, container string, options types.ContainerLogsOptions) (io.ReadCloser, error) {
+	if f.logFunc != nil {
+		return f.logFunc(container, options)
+	}
+	return nil, nil
+}

cli/command/container/logs_test.go

@@ -0,0 +1,62 @@
+package container
+
+import (
+	"io"
+	"io/ioutil"
+	"strings"
+	"testing"
+
+	"github.com/docker/cli/internal/test"
+	"github.com/docker/cli/internal/test/testutil"
+	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/api/types/container"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestRunLogs(t *testing.T) {
+	inspectFn := func(containerID string) (types.ContainerJSON, error) {
+		return types.ContainerJSON{
+			Config:            &container.Config{Tty: true},
+			ContainerJSONBase: &types.ContainerJSONBase{State: &types.ContainerState{Running: false}},
+		}, nil
+	}
+
+	logFn := func(expectedOut string) func(string, types.ContainerLogsOptions) (io.ReadCloser, error) {
+		return func(container string, opts types.ContainerLogsOptions) (io.ReadCloser, error) {
+			return ioutil.NopCloser(strings.NewReader(expectedOut)), nil
+		}
+	}
+
+	var testcases = []struct {
+		doc           string
+		options       *logsOptions
+		client        fakeClient
+		expectedError string
+		expectedOut   string
+		expectedErr   string
+	}{
+		{
+			doc:         "successful logs",
+			expectedOut: "foo",
+			options:     &logsOptions{},
+			client:      fakeClient{logFunc: logFn("foo"), inspectFunc: inspectFn},
+		},
+	}
+
+	for _, testcase := range testcases {
+		t.Run(testcase.doc, func(t *testing.T) {
+			cli := test.NewFakeCli(&testcase.client)
+
+			err := runLogs(cli, testcase.options)
+			if testcase.expectedError != "" {
+				testutil.ErrorContains(t, err, testcase.expectedError)
+			} else {
+				if !assert.NoError(t, err) {
+					return
+				}
+			}
+			assert.Equal(t, testcase.expectedOut, cli.OutBuffer().String())
+			assert.Equal(t, testcase.expectedErr, cli.ErrBuffer().String())
+		})
+	}
+}