Merge pull request #2810 from cag/patch-1

Add docs for `MyContract.transactionHash`

packages/contract/README.md

@@ -148,6 +148,10 @@ This function creates a new instance of the contract abstraction representing th
 
 Creates an instance of the contract abstraction representing the contract at its deployed address. The deployed address is a special value given to @truffle/contract that, when set, saves the address internally so that the deployed address can be inferred from the given Ethereum network being used. This allows you to write code referring to a specific deployed contract without having to manage those addresses yourself. Like `at()`, `deployed()` is thenable, and will resolve to a contract abstraction instance representing the deployed contract after ensuring that code exists at that location and that that address exists on the network being used.
 
+#### `MyContract.transactionHash`
+
+This property accesses the hash of the transaction in which the contract was deployed. This field gets populated for contract objects created with `.deployed()` or `.new()` but not with `.at()`.
+
 #### `MyContract.link(instance)`
 
 Link a library represented by a contract abstraction instance to MyContract. The library must first be deployed and have its deployed address set. The name and deployed address will be inferred from the contract abstraction instance. When this form of `MyContract.link()` is used, MyContract will consume all of the linked library's events and will be able to report that those events occurred during the result of a transaction.