Update resolveRegistration return values in 404 case. (#40)

Author: wilwade

README.md

@@ -4,6 +4,8 @@ The official DSNP interface and implementations.
 
 ## Overview
 
+**Target DSNP Spec Version**: v0.9.1
+
 ### Installation
 
 ```console

contracts/IRegistry.sol

@@ -106,7 +106,7 @@ interface IRegistry {
      * @dev Resolve a handle to a DSNP Id and contract address
      * @param handle The handle to resolve
      *
-     * rejects if not found
+     * Returns zeros if not found
      * @return A tuple of the DSNP Id and the Address of the contract
      */
     function resolveRegistration(string calldata handle) external view returns (uint64, address);

contracts/Registry.sol

@@ -260,7 +260,7 @@ contract Registry is IRegistry {
      * @dev Resolve a handle to a DSNP Id and contract address
      * @param handle The handle to resolve
      *
-     * rejects if not found
+     * Returns zeros if not found
      * @return A tuple of the DSNP Id and the Address of the contract
      */
     function resolveRegistration(string calldata handle)
@@ -271,7 +271,7 @@ contract Registry is IRegistry {
     {
         Registration memory reg = registrations[handle];
 
-        require(reg.id != 0, "Handle does not exist");
+        if (reg.id == 0) return (0, address(0));
 
         return (reg.id, reg.identityAddress);
     }

package-lock.json

@@ -44,16 +44,16 @@
     "chai": "^4.3.4",
     "dotenv": "10.0.0",
     "ethereum-waffle": "^3.4.0",
-    "ethers": "^5.4.1",
+    "ethers": "^5.4.3",
     "hardhat": "^2.4.3",
     "hardhat-gas-reporter": "^1.0.4",
     "js-sha3": "^0.8.0",
     "prettier": "^2.3.2",
-    "prettier-plugin-solidity": "^1.0.0-beta.14",
+    "prettier-plugin-solidity": "^1.0.0-beta.17",
     "solhint": "^3.3.6",
     "solhint-plugin-prettier": "0.0.5",
     "ts-generator": "^0.1.1",
-    "ts-node": "^10.0.0",
+    "ts-node": "^10.1.0",
     "typescript": "^4.3.5"
   },
   "dependencies": {

package.json

@@ -271,10 +271,9 @@ describe("Registry", () => {
 
     it("clears old handle and frees it for registration", async () => {
       await registry.connect(signer1).changeHandle(handle, newHandle);
-
-      await expect(registry.resolveRegistration(handle)).to.be.revertedWith(
-        "Handle does not exist"
-      );
+      const [id, addr] = await registry.resolveRegistration(handle);
+      expect(addr).to.equal("0x0000000000000000000000000000000000000000");
+      expect(id).to.equal("0x00");
 
       await expect(registry.connect(signer2).register(delegate2.address, handle))
         .to.emit(registry, "DSNPRegistryUpdate")
@@ -336,9 +335,9 @@ describe("Registry", () => {
       const { v, r, s } = await signEIP712(signer1, registryDomain, handleChangeTypes, message);
       await registry.connect(signer2).changeHandleByEIP712Sig(v, r, s, message);
 
-      await expect(registry.resolveRegistration(handle)).to.be.revertedWith(
-        "Handle does not exist"
-      );
+      const [id, addr] = await registry.resolveRegistration(handle);
+      expect(addr).to.equal("0x0000000000000000000000000000000000000000");
+      expect(id).to.equal("0x00");
 
       await expect(registry.connect(signer2).register(delegate2.address, handle))
         .to.emit(registry, "DSNPRegistryUpdate")