internal/testkeys: refactor and clean up

[jbowens]

No description provided.

[cockroach-teamcity]

This change is 

[sumeerbhola]

@sumeerbhola reviewed 22 of 22 files at r1, 2 of 2 files at r2, 7 of 7 files at r3, all commit messages.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @jbowens)

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internal/testkeys/testkeys.go line 477 at r3 (raw file):

// exclusive. The receiver is unmodified.
func Slice(ks Keyspace, i, j uint64) Keyspace {
	return &sliceKeyspace{ks: ks, i: i, j: j}

should this panic if i or j are greater than ks.Count?

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internal/testkeys/testkeys.go line 507 at r3 (raw file):

	c := innerCount / n
	if innerCount%n > 0 {
		c++

This could use a comment. Something like:
// We are returning keys at index 0, n, 2n, ... up to cn (to be determined whether inclusive or exclusive), such that the last key is < innerCount. Since cn < innerCount, it becomes inclusive and we return c+1 keys (hence this increment).

[jbowens]

TFTR!

Reviewable status: 16 of 23 files reviewed, 2 unresolved discussions (waiting on @sumeerbhola)

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internal/testkeys/testkeys.go line 477 at r3 (raw file):

Previously, sumeerbhola wrote…

should this panic if i or j are greater than ks.Count?

Done.

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internal/testkeys/testkeys.go line 507 at r3 (raw file):

Previously, sumeerbhola wrote…

This could use a comment. Something like:
// We are returning keys at index 0, n, 2n, ... up to cn (to be determined whether inclusive or exclusive), such that the last key is < innerCount. Since cn < innerCount, it becomes inclusive and we return c+1 keys (hence this increment).

Done.

[sumeerbhola]

@sumeerbhola reviewed 1 of 7 files at r5.
Reviewable status: 17 of 23 files reviewed, 2 unresolved discussions (waiting on @jbowens)