Add unit test for model helper functions

pkg/apis/kops/model/BUILD.bazel

@@ -1,4 +1,4 @@
-load("@io_bazel_rules_go//go:def.bzl", "go_library")
+load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test")
 
 go_library(
     name = "go_default_library",
@@ -9,3 +9,10 @@ go_library(
         "//vendor/k8s.io/apimachinery/pkg/util/sets:go_default_library",
     ],
 )
+
+go_test(
+    name = "go_default_test",
+    srcs = ["utils_test.go"],
+    library = ":go_default_library",
+    deps = ["//pkg/apis/kops:go_default_library"],
+)

pkg/apis/kops/model/utils_test.go

@@ -0,0 +1,170 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+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 model
+
+import (
+	"k8s.io/kops/pkg/apis/kops"
+	"reflect"
+	"testing"
+)
+
+// Test_FindSubnet tests FindSubnet
+func Test_FindSubnet(t *testing.T) {
+	cluster := &kops.Cluster{
+		Spec: kops.ClusterSpec{
+			Subnets: []kops.ClusterSubnetSpec{
+				{Name: "a"},
+				{Name: "b"},
+			},
+		},
+	}
+
+	grid := []struct {
+		cluster     *kops.Cluster
+		subnet      string
+		expectFound bool
+	}{
+		{
+			cluster:     cluster,
+			subnet:      "a",
+			expectFound: true,
+		},
+		{
+			cluster:     cluster,
+			subnet:      "a",
+			expectFound: true,
+		},
+		{
+			cluster:     cluster,
+			subnet:      "ab",
+			expectFound: false,
+		},
+	}
+	for _, g := range grid {
+		actual := FindSubnet(g.cluster, g.subnet)
+		if g.expectFound {
+			if actual == nil {
+				t.Errorf("did not find %q", g.subnet)
+				continue
+			}
+			if actual.Name != g.subnet {
+				t.Errorf("found but had wrong name: %q vs %q", g.subnet, actual.Name)
+			}
+		} else {
+			if actual != nil {
+				t.Errorf("unexpectedly found %q", g.subnet)
+				continue
+			}
+		}
+	}
+}
+
+// Test_FindZonesForInstanceGroup tests FindZonesForInstanceGroup
+func Test_FindZonesForInstanceGroup(t *testing.T) {
+	cluster := &kops.Cluster{
+		Spec: kops.ClusterSpec{
+			Subnets: []kops.ClusterSubnetSpec{
+				{Name: "zonea", Zone: "zonea"},
+				{Name: "zoneb", Zone: "zoneb"},
+			},
+		},
+	}
+
+	grid := []struct {
+		cluster     *kops.Cluster
+		ig          *kops.InstanceGroup
+		expected    []string
+		expectError bool
+	}{
+		{
+			cluster: cluster,
+			ig: &kops.InstanceGroup{
+				Spec: kops.InstanceGroupSpec{
+					Subnets: []string{"zonea"},
+				},
+			},
+			expected: []string{"zonea"},
+		},
+		{
+			cluster: cluster,
+			ig: &kops.InstanceGroup{
+				Spec: kops.InstanceGroupSpec{
+					Subnets: []string{"zonea", "zoneb"},
+				},
+			},
+			expected: []string{"zonea", "zoneb"},
+		},
+		{
+			cluster: cluster,
+			ig: &kops.InstanceGroup{
+				Spec: kops.InstanceGroupSpec{
+					Subnets: []string{"zoneb", "zonea"},
+				},
+			},
+			// Order is not preserved (they are in fact sorted)
+			expected: []string{"zonea", "zoneb"},
+		},
+		{
+			cluster: cluster,
+			ig: &kops.InstanceGroup{
+				Spec: kops.InstanceGroupSpec{
+					Subnets: []string{"zoneb", "nope"},
+				},
+			},
+			expectError: true,
+		},
+		{
+			cluster: cluster,
+			ig: &kops.InstanceGroup{
+				Spec: kops.InstanceGroupSpec{
+					Zones: []string{"directa", "directb"},
+				},
+			},
+			expected: []string{"directa", "directb"},
+		},
+		{
+			cluster: cluster,
+			ig: &kops.InstanceGroup{
+				Spec: kops.InstanceGroupSpec{
+					Zones:   []string{"directa", "directb"},
+					Subnets: []string{"zonea", "zoneb"},
+				},
+			},
+			// Not sure if we actually should merge here - should the IG zones actually act as a restriction on the Subnet zones?
+			// For now, this isn't likely to come up, so we test the current behaviour
+			expected: []string{"directa", "directb", "zonea", "zoneb"},
+		},
+	}
+	for i, g := range grid {
+		actual, err := FindZonesForInstanceGroup(g.cluster, g.ig)
+		if err != nil {
+			if g.expectError {
+				continue
+			}
+			t.Errorf("unexpected error for %d: %v", i, err)
+			continue
+		}
+		if g.expectError {
+			t.Errorf("expected error for %d, result was %v", i, actual)
+			continue
+		}
+		if !reflect.DeepEqual(actual, g.expected) {
+			t.Errorf("unexpected result for %d: actual=%v, expected=%v", i, actual, g.expected)
+			continue
+		}
+	}
+}