1  
 2  // This has been tested with the real Ethereum network and Testrpc.
 3  // Copied and edited from: https://gist.github.com/xavierlepretre/d5583222fde52ddfbc58b7cfa0d2d0a9
 4  exports.assertReverts = (contractMethodCall, maxGasAvailable) => {
 5      return new Promise((resolve, reject) => {
 6          try {
 7              resolve(contractMethodCall())
 8          } catch (error) {
 9              reject(error)
10          }
11      })
12          .then(tx => {
13              assert.equal(tx.receipt.gasUsed, maxGasAvailable, "tx successful, the max gas available was not consumed")
14          })
15          .catch(error => {
16              if ((error + "").indexOf("invalid opcode") < 0 && (error + "").indexOf("out of gas") < 0) {
17                  // Checks if the error is from TestRpc. If it is then ignore it.
18                  // Otherwise relay/throw the error produced by the above assertion.
19                  // Note that no error is thrown when using a real Ethereum network AND the assertion above is true.
20                  throw error
21              }
22          })
23  }
24  
25  exports.listenForEvent = event => new Promise((resolve, reject) => {
26      event.watch((error, response) => {
27          if (!error) {
28              resolve(response.args)
29          } else {
30              reject(error)
31          }
32          event.stopWatching()
33      })
34  })