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@zhifei92 It would also make sense to look at the existing calls of the context.Background() and the context.TODO(). Some of them could be replaced by ctx or context.TODO() with a comment:

$ git grep '\(Background()\)\|\(TODO()\)' ./pkg/kubelet/metrics/
pkg/kubelet/metrics/collectors/cri_metrics.go:  ctx := context.TODO()
pkg/kubelet/metrics/collectors/log_metrics.go:  ctx := context.TODO()
pkg/kubelet/metrics/collectors/resource_metrics.go:     ctx := context.Background()
pkg/kubelet/metrics/collectors/resource_metrics_test.go:                        ctx := context.Background()
pkg/kubelet/metrics/collectors/volume_stats.go: ctx := context.Background()
pkg/kubelet/metrics/collectors/volume_stats_test.go:    ctx := context.Background()
pkg/kubelet/metrics/collectors/volume_stats_test.go:    ctx := context.Background()

It would also make sense to look at the existing calls of the context.Background() and the context.TODO().

Sorry for not reading the requirements document carefully.

/triage accepted
/priority important-longterm

/assign

/retest

@zhifei92 I can see context.TODO() calls, even in tests. Are you sure we can't remove them or move to the upper level?

@zhifei92 I can see context.TODO() calls, even in tests. Are you sure we can't remove them or move to the upper level?

Because the gomock method verifies the parameters passed to the GetCPUAndMemoryStats method (including the specific type of context), I am unsure whether to continue using context.TODO() or to use gomock.Any() to ignore the context parameter.

Like this:

	for _, test := range tests {
		tc := test
		t.Run(tc.name, func(t *testing.T) {
			ctx := context.TODO()
			provider := summaryprovidertest.NewMockSummaryProvider(t)
			provider.EXPECT().GetCPUAndMemoryStats(ctx).Return(tc.summary, tc.summaryErr).Maybe()

Because the gomock method verifies the parameters passed to the GetCPUAndMemoryStats method (including the specific type of context), I am unsure whether to continue using context.TODO() or to use gomock.Any() to ignore the context parameter.

Can you show how it would look like with gomock.Any() ?

@zhifei92

Because the gomock method verifies the parameters passed to the GetCPUAndMemoryStats method (including the specific type of context), I am unsure whether to continue using context.TODO() or to use gomock.Any() to ignore the context parameter.

Even if we manage to use the same context it wouldn't help. reflect.DeepEqual, which is called by mocking APIs to verify parameters, is not good at comparing interfaces, context.Context in this particular case. As an example, this trivial test case always fails:

func TestCtxEquality(t *testing.T) {
	ctx := ktesting.Init(t)
	if !reflect.DeepEqual(ctx, ctx) {
		t.Fatal("not equal")
	}
} 

Can we mock context with mock.MatchedBy to make any argument implementing context.Context to match?

If this is not possible, can we switch to passing logger instead of context?

Can you show how it would look like with gomock.Any() ?

Using mock.Anything to ignore the comparison of ctx in a mock API is simpler than using MatchedBy. How do you see this?

	// Anything is used in Diff and Assert when the argument being tested
	// shouldn't be taken into consideration.
	Anything = "mock.Anything"

If this is not possible, can we switch to passing logger instead of context?

This approach is not feasible, since it involves making substantial modifications to the existing codebase.

@zhifei92: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Full PR test history. Your PR dashboard. Please help us cut down on flakes by linking to an open issue when you hit one in your PR.