record: add logger to reader, update walSync test to use logger

[EdwardX29]

add test logger to walSync test.

[cockroach-teamcity]

This change is 

[sumeerbhola]

Reviewed all commit messages.
Reviewable status: 0 of 3 files reviewed, 3 unresolved discussions

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record/record.go line 257 at r1 (raw file):

	// readerLogger is a logging helper used by the Reader to accumulate log messages.
	logger *readerLogger

Since this is for testing, the usual idiom is to have the field be called loggerForTesting. And also hide the implementation in a test go file. Which implies declaring an interface here. So something like

  loggerForTesting loggerForTesting
}

type loggerForTesting interface {
   Logf(format string, args ...interface{})
}

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record/record.go line 264 at r1 (raw file):

}

func (l *readerLogger) Log(s string) {

why do we need this method when we have Logf which subsumes this behavior?

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record/record.go line 274 at r1 (raw file):

func (l *readerLogger) Logf(format string, args ...interface{}) {
	msg := fmt.Sprintf(format, args...)

fmt.Fprintf(&l.builder, format, args...) should be sufficient.

[EdwardX29]

Reviewable status: 0 of 3 files reviewed, 3 unresolved discussions (waiting on @sumeerbhola)

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record/record.go line 257 at r1 (raw file):

Previously, sumeerbhola wrote…

Since this is for testing, the usual idiom is to have the field be called loggerForTesting. And also hide the implementation in a test go file. Which implies declaring an interface here. So something like

  loggerForTesting loggerForTesting
}

type loggerForTesting interface {
   Logf(format string, args ...interface{})
}

done

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record/record.go line 264 at r1 (raw file):

Previously, sumeerbhola wrote…

why do we need this method when we have Logf which subsumes this behavior?

removed

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record/record.go line 274 at r1 (raw file):

Previously, sumeerbhola wrote…

fmt.Fprintf(&l.builder, format, args...) should be sufficient.

done

[sumeerbhola]

Reviewed 1 of 3 files at r2.
Reviewable status: 1 of 3 files reviewed, 6 unresolved discussions (waiting on @jbowens)

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a discussion (no related file):

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record/record.go line 259 at r2 (raw file):

type loggerForTesting interface {
	Logf(format string, args ...interface{})

nit: logf (since package private is sufficient)

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record/record.go line 260 at r2 (raw file):

type loggerForTesting interface {
	Logf(format string, args ...interface{})
	GetLog() string

getLog doesn't need to be in the interface, since it is called by the test code which knows it is dealing with a readerLogger.

[sumeerbhola]

Reviewed 1 of 3 files at r2, 2 of 2 files at r3.
Reviewable status: all files reviewed (commit messages unreviewed), 6 unresolved discussions (waiting on @EdwardX29 and @jbowens)

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a discussion (no related file):

Previously, sumeerbhola wrote…