Add unit tests with fake client-go for all parts of controller

[invidian]

Given that this operator simply operates on Node objects, we should be able to use client-go to run both operator and node agent usign fake client-go and with mock D-Bus to test most parts of those controllers.

[invidian]

For operator, following tests must still be added:

• Test New() constructor

FAIL "/tmp/go-mutesting-068518235/pkg/operator/agent_manager.go.5" with checksum d1d55f49f782e9210654d61f82593b99
Mutate "pkg/operator/operator.go"
--- pkg/operator/operator.go    2021-06-09 09:35:27.556903533 +0200
+++ /tmp/go-mutesting-068518235/pkg/operator/operator.go.0      2021-06-09 09:37:21.034736036 +0200
@@ -130,7 +130,7 @@
 func New(config Config) (*Kontroller, error) {
        // Kubernetes client.
        if config.Client == nil {
-               return nil, fmt.Errorf("kubernetes client must not be nil")
+               _ = fmt.Errorf
        }

        namespace := os.Getenv("POD_NAMESPACE")

FAIL "/tmp/go-mutesting-068518235/pkg/operator/operator.go.0" with checksum 10e5a9c80ecb59d2cd4458c315a5b47b
--- pkg/operator/operator.go    2021-06-09 09:35:27.556903533 +0200
+++ /tmp/go-mutesting-068518235/pkg/operator/operator.go.1      2021-06-09 09:37:28.131506959 +0200
@@ -135,8 +135,8 @@

        namespace := os.Getenv("POD_NAMESPACE")
        if namespace == "" {
-               return nil, fmt.Errorf("unable to determine operator namespace: please ensure POD_NAMESPACE " +
-                       "environment variable is set")
+               _ = fmt.Errorf
+
        }

        // TODO: a better id might be necessary.

FAIL "/tmp/go-mutesting-068518235/pkg/operator/operator.go.1" with checksum a21ce2afe9752ccf387819f756ed0fb0
--- pkg/operator/operator.go    2021-06-09 09:35:27.556903533 +0200
+++ /tmp/go-mutesting-068518235/pkg/operator/operator.go.2      2021-06-09 09:37:29.514860983 +0200
@@ -145,7 +145,7 @@
        // more likely to have a value.
        hostname, err := os.Hostname()
        if err != nil {
-               return nil, fmt.Errorf("getting hostname: %w", err)
+               _, _ = fmt.Errorf, err
        }

        var rebootWindow *timeutil.Periodic

FAIL "/tmp/go-mutesting-068518235/pkg/operator/operator.go.2" with checksum fb294b54e8a7490e34e018130c1511c9
Mutation did not compile
SKIP "/tmp/go-mutesting-068518235/pkg/operator/operator.go.3" with checksum 60255384368834043f9d7a377002468f
--- pkg/operator/operator.go    2021-06-09 09:35:27.556903533 +0200
+++ /tmp/go-mutesting-068518235/pkg/operator/operator.go.4      2021-06-09 09:37:31.378222365 +0200
@@ -153,7 +153,7 @@
        if config.RebootWindowStart != "" && config.RebootWindowLength != "" {
                rw, err := timeutil.ParsePeriodic(config.RebootWindowStart, config.RebootWindowLength)
                if err != nil {
-                       return nil, fmt.Errorf("parsing reboot window: %w", err)
+                       _, _ = fmt.Errorf, err
                }

                rebootWindow = rw

• (Optional) test auto-labeler

FAIL "/tmp/go-mutesting-068518235/pkg/operator/operator.go.43" with checksum 2961cdc6043ea49e15f279886ccd536f
--- pkg/operator/operator.go    2021-06-09 09:35:27.556903533 +0200
+++ /tmp/go-mutesting-068518235/pkg/operator/operator.go.44     2021-06-09 09:40:39.155245246 +0200
@@ -201,7 +201,7 @@

        // Start Flatcar Container Linux node auto-labeler.
        if k.autoLabelContainerLinux {
-               go wait.Until(func() { k.legacyLabeler(ctx) }, k.reconciliationPeriod, ctx.Done())
+               go wait.Until(func() { _, _ = k.legacyLabeler, ctx }, k.reconciliationPeriod, ctx.Done())
        }

        klog.V(5).Info("starting controller")

• Few other cases which should be analyzed, as they might be source of some subtle bugs:

--- pkg/operator/operator.go    2021-06-09 09:35:27.556903533 +0200
+++ /tmp/go-mutesting-068518235/pkg/operator/operator.go.28     2021-06-09 09:39:49.577466457 +0200
@@ -504,7 +504,7 @@
        rebootingNodes = append(rebootingNodes, afterRebootNodes...)

        // Verify the number of currently rebooting nodes is less than the the maximum number.
-       if len(rebootingNodes) >= k.maxRebootingNodes {
+       if len(rebootingNodes) > k.maxRebootingNodes {
                for _, n := range rebootingNodes {
                        klog.Infof("Found node %q still rebooting, waiting", n.Name)
                }

FAIL "/tmp/go-mutesting-068518235/pkg/operator/operator.go.28" with checksum b3cf0a6acede66bad151008bddd0ca1c
--- pkg/operator/operator.go    2021-06-09 09:35:27.556903533 +0200
+++ /tmp/go-mutesting-068518235/pkg/operator/operator.go.29     2021-06-09 09:39:55.750933852 +0200
@@ -523,7 +523,7 @@

        // Choose some number of nodes.
        chosenNodes := make([]*corev1.Node, 0, remainingRebootableCount)
-       for i := 0; i < remainingRebootableCount && i < len(rebootableNodes); i++ {
+       for i := 0; i <= remainingRebootableCount && i < len(rebootableNodes); i++ {
                chosenNodes = append(chosenNodes, &rebootableNodes[i])
        }


FAIL "/tmp/go-mutesting-068518235/pkg/operator/operator.go.29" with checksum c8d2cd7949c2e71e232171a67e6a1e10
PASS "/tmp/go-mutesting-068518235/pkg/operator/operator.go.30" with checksum d6db1c5e6969cbb246a129f7fa80ee7d
--- pkg/operator/operator.go    2021-06-09 09:35:27.556903533 +0200
+++ /tmp/go-mutesting-068518235/pkg/operator/operator.go.31     2021-06-09 09:40:03.997781656 +0200
@@ -587,7 +587,7 @@
                return fmt.Errorf("setting label %q to %q on node %q: %w", label, constants.True, nodeName, err)
        }

-       if len(annotations) > 0 {
+       if len(annotations) >= 0 {
                klog.Infof("Waiting for %s annotations on node %q: %v", annotationsType, nodeName, annotations)
        }


FAIL "/tmp/go-mutesting-068518235/pkg/operator/operator.go.31" with checksum e0c432d45d9320fc7b24663c2a1b2029
--- pkg/operator/operator.go    2021-06-09 09:35:27.556903533 +0200
+++ /tmp/go-mutesting-068518235/pkg/operator/operator.go.32     2021-06-09 09:40:11.104606254 +0200
@@ -150,7 +150,7 @@

        var rebootWindow *timeutil.Periodic

-       if config.RebootWindowStart != "" && config.RebootWindowLength != "" {
+       if true && config.RebootWindowLength != "" {
                rw, err := timeutil.ParsePeriodic(config.RebootWindowStart, config.RebootWindowLength)
                if err != nil {
                        return nil, fmt.Errorf("parsing reboot window: %w", err)

FAIL "/tmp/go-mutesting-068518235/pkg/operator/operator.go.32" with checksum 37341006ccf25fa3c57423dfd8fe336b
--- pkg/operator/operator.go    2021-06-09 09:35:27.556903533 +0200
+++ /tmp/go-mutesting-068518235/pkg/operator/operator.go.33     2021-06-09 09:40:13.297988665 +0200
@@ -150,7 +150,7 @@

        var rebootWindow *timeutil.Periodic

-       if config.RebootWindowStart != "" && config.RebootWindowLength != "" {
+       if config.RebootWindowStart != "" && true {
                rw, err := timeutil.ParsePeriodic(config.RebootWindowStart, config.RebootWindowLength)
                if err != nil {
                        return nil, fmt.Errorf("parsing reboot window: %w", err)

FAIL "/tmp/go-mutesting-068518235/pkg/operator/operator.go.33" with checksum e58d4ceb1c572eb917ecedb02f58e705
--- pkg/operator/operator.go    2021-06-09 09:35:27.556903533 +0200
+++ /tmp/go-mutesting-068518235/pkg/operator/operator.go.34     2021-06-09 09:40:14.638018725 +0200
@@ -523,7 +523,7 @@

        // Choose some number of nodes.
        chosenNodes := make([]*corev1.Node, 0, remainingRebootableCount)
-       for i := 0; i < remainingRebootableCount && i < len(rebootableNodes); i++ {
+       for i := 0; true && i < len(rebootableNodes); i++ {
                chosenNodes = append(chosenNodes, &rebootableNodes[i])
        }


FAIL "/tmp/go-mutesting-068518235/pkg/operator/operator.go.34" with checksum 2ff3cca35e3e0e47842e240943ef1b36

[invidian]

Agent tests has been finally added in #116. We have left:

• cmd tests for both operator and agent.
• pkg/version (though this should likely be removed as part of Consider getting rid of version constraints from code #135
• pkg/k8sutil - see Reduce amount of code in pkg/k8sutil package #137
• pkg/operator - we need to add tests for handling errors