some leveldown test files

1-test-close-while-put-segfault.js

// segfaults
var levelup = require('levelup')             
var db = levelup('./test1.db')                      
                                                     
db.put('foo', 'bar', { sync: true }, function (err) {
  console.log('back from put', err)             
})                           
                                                     
db.close(function (err) {                            
  console.log('closed the db', err)             
})                                            

2-test-iterator-without-open.js

// segfaults
var db = require('leveldown')('./test2.db')
var iterator = db.iterator()               

3-test-close-db-with-read-stream.js

// this should be extracted to a test file for leveldown, the stream _should_ error
const level = require('levelup')           
const db = level('./test3.db')                   
const N = 10000                                  
const batch = []                                 
for (var i = 0; i < N; i++) {                    
  batch.push({ type: 'put', key: i, value: 'a' })
}                                                
                                                 
db.batch(batch, function (err) {                 
  if (err) throw err                             
                                                 
  db.createReadStream()                          
    .once('data', function (data) {              
      db.close()                                 
    })                                           
    .on('error', function (err) {                
      console.log('readstream error')            
    })                                           
})