input+sweep: make sure input with no fee rate is not added to cluster

[yyforyongyu]

During a debugging process, an edge case is found when creating clusters for locked inputs. This PR makes sure an input is only added to the cluster when it has successfully estimated its fee rate. Previously, when an error is returned from feeRateForPreference, we'd still add this input to the cluster, resulting in a lower fee rate being used because when averaging the fee rates, we'd think this input has zero fee rate specified.

Several unit tests are patched to make the method clusterByLockTime more robust.

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This change is 

[yyforyongyu]

cc @ziggie1984

[ziggie1984]

Really cool new tests, learned how to use the mocks package 🤓. Had only minor nits.

Reviewed 6 of 6 files at r1, all commit messages.
Reviewable status: all files reviewed, 8 unresolved discussions (waiting on @yyforyongyu)

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input/mocks.go line 9 at r1 (raw file):

)

// MockInput implement the `Input` interface and is used by other packages for

Nit: implements

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sweep/sweeper.go line 250 at r1 (raw file):

// feeDeterminor defines an alias to the function signature of
// `DetermineFeePerKw`.
type feeDeterminor func(chainfee.Estimator,

Nit: s/Determinor/Determiner/g

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sweep/sweeper.go line 970 at r1 (raw file):

		// Get the fee rate based on the fee preference. If an error is
		// returned, we'll skip sweeping this input for this round of

Nice catch 👏

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sweep/sweeper_test.go line 2323 at r1 (raw file):

	}

	// Set the max fee rate to be 1000.

Nit: 1000 sat/kw

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sweep/sweeper_test.go line 2335 at r1 (raw file):

	// testFeeRate is used to test the success case.
	testFeeRate := (s.cfg.MaxFeeRate + s.relayFeeRate) / 2

Nit: s/testFeeRate/validFeeRate ?

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sweep/sweeper_test.go line 2405 at r1 (raw file):

			// Assert the expected feerate.
			require.Equal(t, tc.expectedFeeRate, feerate)

first check for error and maybe skip the fee check if an error is expected ?

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sweep/sweeper_test.go line 2414 at r1 (raw file):

// TestClusterByLockTime tests the method clusterByLockTime works as expected.
func TestClusterByLockTime(t *testing.T) {

I like this test 👏

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sweep/sweeper_test.go line 2488 at r1 (raw file):

	// Create a test sweeper.
	s := New(&UtxoSweeperConfig{
		// Set the max fee rate to be 1000.

Nit: 1000 sat/kw

[yyforyongyu]

Reviewable status: all files reviewed, 3 unresolved discussions (waiting on @ziggie1984)

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sweep/sweeper.go line 970 at r1 (raw file):

Previously, ziggie1984 (ziggieXXX) wrote…

Nice catch 👏

🤓

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sweep/sweeper_test.go line 2405 at r1 (raw file):

Previously, ziggie1984 (ziggieXXX) wrote…

first check for error and maybe skip the fee check if an error is expected ?

I think it's more robust to check all the returned values.

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sweep/sweeper_test.go line 2414 at r1 (raw file):

Previously, ziggie1984 (ziggieXXX) wrote…

I like this test 👏

Done.😈

[lightninglabs-deploy]

@Roasbeef: review reminder

[saubyk]

Concept Ack.
cc: @guggero this can be merged