Update solidity version in contracts

Author: njgheorghita

contracts/Migrations.sol

@@ -1,4 +1,6 @@
-pragma solidity ^0.5.0;
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.6.0;
 
 /**
  * @dev Contract module which provides a basic access control mechanism, where

contracts/Ownable.sol

@@ -1,4 +1,6 @@
-pragma solidity >=0.5.10;
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.6.0;
 
 import {PackageRegistryInterface} from "./PackageRegistryInterface.sol";
 import {Ownable} from "./Ownable.sol";
@@ -69,6 +71,7 @@ contract PackageRegistry is PackageRegistryInterface, Ownable {
         string memory manifestURI
     )
         public
+        override
         onlyOwner
         returns (bytes32)
     {
@@ -140,6 +143,7 @@ contract PackageRegistry is PackageRegistryInterface, Ownable {
     /// @param packageId The package id to look up
     function getPackageName(bytes32 packageId)
         public
+        override
         view
         returns (string memory packageName)
     {
@@ -153,6 +157,7 @@ contract PackageRegistry is PackageRegistryInterface, Ownable {
     /// @param limit  The length of the slice
     function getAllPackageIds(uint offset, uint limit)
         public
+        override
         view
         returns (
             bytes32[] memory packageIds,
@@ -194,6 +199,7 @@ contract PackageRegistry is PackageRegistryInterface, Ownable {
     /// @param limit  The length of the slice
     function getAllReleaseIds(string memory packageName, uint offset, uint limit)
         public
+        override
         view
         onlyIfPackageExists(packageName)
         returns (
@@ -239,6 +245,7 @@ contract PackageRegistry is PackageRegistryInterface, Ownable {
     /// @param releaseId Release id
     function getReleaseData(bytes32 releaseId)
         public
+        override
         view
         returns (
             string memory packageName, string memory version,
@@ -255,6 +262,7 @@ contract PackageRegistry is PackageRegistryInterface, Ownable {
     /// @param version Version string(ex: '1.0.0')
     function getReleaseId(string memory packageName, string memory version)
         public
+        override
         view
         onlyIfPackageExists(packageName)
         onlyIfReleaseExists(packageName, version)
@@ -264,7 +272,7 @@ contract PackageRegistry is PackageRegistryInterface, Ownable {
     }
 
     /// @dev Returns the number of packages stored on the registry
-    function numPackageIds() public view returns (uint totalCount)
+    function numPackageIds() public override view returns (uint totalCount)
     {
         return packageCount;
     }
@@ -273,6 +281,7 @@ contract PackageRegistry is PackageRegistryInterface, Ownable {
     /// @param packageName Package name
     function numReleaseIds(string memory packageName)
         public
+        override
         view
         onlyIfPackageExists(packageName)
         returns (uint totalCount)
@@ -327,6 +336,7 @@ contract PackageRegistry is PackageRegistryInterface, Ownable {
         string memory version
     )
         public
+        override
         view
         returns (bytes32)
     {

contracts/PackageRegistry.sol

@@ -1,9 +1,11 @@
-pragma solidity >=0.5.10;
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.6.0;
 
 
 /// @title EIP 1319 Smart Contract Package Registry Interface
 /// @author Piper Merriam <[email protected]>, Christopher Gewecke <[email protected]>
-contract PackageRegistryInterface {
+abstract contract PackageRegistryInterface {
 
     //
     // +-------------+
@@ -22,6 +24,7 @@ contract PackageRegistryInterface {
         string memory manifestURI
     )
         public
+        virtual
         returns (bytes32 releaseId);
 
     //
@@ -34,6 +37,7 @@ contract PackageRegistryInterface {
     /// @param packageId The package id to look up
     function getPackageName(bytes32 packageId)
         public
+        virtual
         view
         returns (string memory packageName);
 
@@ -42,6 +46,7 @@ contract PackageRegistryInterface {
     /// @param limit  The length of the slice
     function getAllPackageIds(uint offset, uint limit)
         public
+        virtual
         view
         returns (
             bytes32[] memory packageIds,
@@ -54,6 +59,7 @@ contract PackageRegistryInterface {
     /// @param limit  The length of the slice
     function getAllReleaseIds(string memory packageName, uint offset, uint limit)
         public
+        virtual
         view
         returns (
             bytes32[] memory releaseIds,
@@ -64,6 +70,7 @@ contract PackageRegistryInterface {
     /// @param releaseId Release id
     function getReleaseData(bytes32 releaseId)
         public
+        virtual
         view
         returns (
             string memory packageName,
@@ -76,6 +83,7 @@ contract PackageRegistryInterface {
     // @param version Version string (ex: '1.0.0')
     function generateReleaseId(string memory packageName, string memory version)
         public
+        virtual
         view
         returns (bytes32 releaseId);
 
@@ -84,13 +92,14 @@ contract PackageRegistryInterface {
     /// @param version Version string(ex: '1.0.0')
     function getReleaseId(string memory packageName, string memory version)
         public
+        virtual
         view
         returns (bytes32 releaseId);
 
     /// @dev Returns the number of packages stored on the registry
-    function numPackageIds() public view returns (uint totalCount);
+    function numPackageIds() public virtual view returns (uint totalCount);
 
     /// @dev Returns the number of releases for a given package name on the registry
     /// @param packageName Package name
-    function numReleaseIds(string memory packageName) public view returns (uint totalCount);
+    function numReleaseIds(string memory packageName) public virtual view returns (uint totalCount);
 }

contracts/PackageRegistryInterface.sol

@@ -1,5 +1,5 @@
-const Migrations = artifacts.require("Migrations");
+const PackageRegistry = artifacts.require("PackageRegistry");
 
 module.exports = function(deployer) {
-  deployer.deploy(Migrations);
+  deployer.deploy(PackageRegistry);
 };