expand test coverage

Author: 0age

README.md

@@ -99,7 +99,7 @@ Contracts may also be deployed locally using `$ node scripts/deploy.js`.
  * remove attributes from participants as required.
 
 
-* A **TPLToken** is a standard [OpenZeppelin ERC20 token](https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/token/ERC20/StandardToken.sol) that enforces attribute checks during every token transfer. For this [implementation](https://github.com/TPL-protocol/tpl-contracts/blob/master/contracts/token/TPLRestrictedReceiverToken.sol), the token checks the jurisdiction's registry for an attribute used to whitelist valid token recipients. The additional overhead for each transaction in the minimum-case is **4156 gas**, with 1512 used to execute jurisdiction contract logic and 2644 for general "plumbing" (the overhead of checking against an external call to the registry that simply returns `true`). *(NOTE: the attributes defined in the jurisdiction and required by TPLToken have been arbitrarily defined for this PoC, and are not intended to serve as a proposal for the attributes that will be used for validating transactions.)*
+* An example **TPL-enabled ERC20** that uses a standard [OpenZeppelin ERC20 token](https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/token/ERC20/StandardToken.sol) to enforce attribute checks during every token transfer is also included. For this [implementation](https://github.com/TPL-protocol/tpl-contracts/blob/master/contracts/token/TPLRestrictedReceiverToken.sol), the token checks the jurisdiction's registry for an attribute used to whitelist valid token recipients. The additional overhead for each transaction in the minimum-case is **4156 gas**, with 1512 used to execute jurisdiction contract logic and 2644 for general "plumbing" (the overhead of checking against an external call to the registry that simply returns `true`). *(NOTE: the attributes defined in the jurisdiction and required by TPLToken have been arbitrarily defined for this PoC, and are not intended to serve as a proposal for the attributes that will be used for validating transactions.)*
 
 
 #### Attribute scope

contracts/Jurisdiction.sol

@@ -1296,7 +1296,7 @@ contract Jurisdiction is Ownable, Pausable, AttributeRegistryInterface, BasicJur
  );
  }
 
- // users can check whether a signature for adding an attribute is still valid
+ // users can check whether a signed attribute approval is currently valid
  function canAddAttribute(
  uint256 attributeTypeID,
  uint256 value,
@@ -1322,15 +1322,17 @@ contract Jurisdiction is Ownable, Pausable, AttributeRegistryInterface, BasicJur
  uint256 minimumStake = _attributeTypes[attributeTypeID].minimumStake;
  uint256 jurisdictionFee = _attributeTypes[attributeTypeID].jurisdictionFee;
 
- // determine if the attribute can still be added
+ // determine if the attribute can currently be added.
+ // NOTE: consider returning an error code along with the boolean.
  return (
  fundsRequired >= minimumStake.add(jurisdictionFee).add(validatorFee) &&
  _invalidAttributeApprovalHashes[hash] == false &&
- canValidate(validator, attributeTypeID)
+ canValidate(validator, attributeTypeID) &&
+ _issuedAttributes[msg.sender][attributeTypeID].exists == false
  );
  }
 
- // operators can check whether an attribute approval signature is still valid
+ // operators can check whether a signed attribute approval is currently valid
  function canAddAttributeFor(
  address account,
  uint256 attributeTypeID,
@@ -1357,11 +1359,13 @@ contract Jurisdiction is Ownable, Pausable, AttributeRegistryInterface, BasicJur
  uint256 minimumStake = _attributeTypes[attributeTypeID].minimumStake;
  uint256 jurisdictionFee = _attributeTypes[attributeTypeID].jurisdictionFee;
 
- // determine if the attribute can still be added
+ // determine if the attribute can currently be added.
+ // NOTE: consider returning an error code along with the boolean.
  return (
  fundsRequired >= minimumStake.add(jurisdictionFee).add(validatorFee) &&
  _invalidAttributeApprovalHashes[hash] == false &&
- canValidate(validator, attributeTypeID)
+ canValidate(validator, attributeTypeID) &&
+ _issuedAttributes[account][attributeTypeID].exists == false
  );
  }