Move modifying OCI runtime wrapper to oci package

Signed-off-by: Evan Lezar <elezar@nvidia.com>

internal/oci/runtime_modifier_test.go

@@ -0,0 +1,163 @@
+/*
+# Copyright (c) 2022, NVIDIA CORPORATION.  All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+*/
+
+package oci
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/opencontainers/runtime-spec/specs-go"
+	testlog "github.com/sirupsen/logrus/hooks/test"
+	"github.com/stretchr/testify/require"
+)
+
+func TestExec(t *testing.T) {
+	logger, hook := testlog.NewNullLogger()
+
+	testCases := []struct {
+		description   string
+		shouldLoad    bool
+		shouldModify  bool
+		shouldFlush   bool
+		shouldForward bool
+		args          []string
+		modifyError   error
+		writeError    error
+		modifer       SpecModifier
+	}{
+		{
+			description:   "no args forwards",
+			shouldLoad:    false,
+			shouldModify:  false,
+			shouldFlush:   false,
+			shouldForward: true,
+			modifer:       &modiferMock{},
+		},
+		{
+			description:   "create modifies",
+			args:          []string{"create"},
+			shouldLoad:    true,
+			shouldModify:  true,
+			shouldFlush:   true,
+			shouldForward: true,
+			modifer:       &modiferMock{},
+		},
+		{
+			description:   "modify error does not write or forward",
+			args:          []string{"create"},
+			modifyError:   fmt.Errorf("error modifying"),
+			shouldLoad:    true,
+			shouldModify:  true,
+			shouldFlush:   false,
+			shouldForward: false,
+			modifer:       &modiferMock{},
+		},
+		{
+			description:   "write error does not forward",
+			args:          []string{"create"},
+			writeError:    fmt.Errorf("error writing"),
+			shouldLoad:    true,
+			shouldModify:  true,
+			shouldFlush:   true,
+			shouldForward: false,
+			modifer:       &modiferMock{},
+		},
+		{
+			description:   "nil modifier forwards on create",
+			args:          []string{"create"},
+			shouldLoad:    false,
+			shouldModify:  false,
+			shouldFlush:   false,
+			shouldForward: true,
+			modifer:       nil,
+		},
+	}
+
+	for _, tc := range testCases {
+		hook.Reset()
+
+		t.Run(tc.description, func(t *testing.T) {
+			runtimeMock := &RuntimeMock{}
+			specMock := &SpecMock{
+				ModifyFunc: func(specModifier SpecModifier) error {
+					return tc.modifyError
+				},
+				FlushFunc: func() error {
+					return tc.writeError
+				},
+			}
+
+			shim := NewModifyingRuntimeWrapper(
+				logger,
+				runtimeMock,
+				specMock,
+				// TODO: We should test the interactions with the SpecModifier too
+				tc.modifer,
+			)
+
+			err := shim.Exec(tc.args)
+			if tc.modifyError != nil || tc.writeError != nil {
+				require.Error(t, err)
+			} else {
+				require.NoError(t, err)
+			}
+
+			if tc.shouldLoad {
+				require.Equal(t, 1, len(specMock.LoadCalls()))
+			} else {
+				require.Equal(t, 0, len(specMock.LoadCalls()))
+			}
+			if tc.shouldModify {
+				require.Equal(t, 1, len(specMock.ModifyCalls()))
+			} else {
+				require.Equal(t, 0, len(specMock.ModifyCalls()))
+			}
+			if tc.shouldFlush {
+				require.Equal(t, 1, len(specMock.FlushCalls()))
+			} else {
+				require.Equal(t, 0, len(specMock.FlushCalls()))
+			}
+			if tc.shouldForward {
+				require.Equal(t, 1, len(runtimeMock.ExecCalls()))
+			} else {
+				require.Equal(t, 0, len(runtimeMock.ExecCalls()))
+			}
+		})
+	}
+}
+
+func TestNilModiferReturnsRuntime(t *testing.T) {
+	logger, _ := testlog.NewNullLogger()
+
+	runtimeMock := &RuntimeMock{}
+	specMock := &SpecMock{}
+
+	shim := NewModifyingRuntimeWrapper(
+		logger,
+		runtimeMock,
+		specMock,
+		nil,
+	)
+
+	require.Equal(t, runtimeMock, shim)
+}
+
+type modiferMock struct{}
+
+func (m modiferMock) Modify(*specs.Spec) error {
+	return nil
+}