@ -9,14 +9,12 @@ Here we describe when you should expect new releases to come out, and how this a
OpenZeppelin Contracts follows a <<versioning-scheme, semantic versioning scheme>>.
[[minor-releases]]
=== Minor Releases
OpenZeppelin Contracts aims for a new minor release every 1 or 2 months.
We aim for a new minor release every 1 or 2 months.
At the beginning of the release cycle we decide which issues we want to prioritize, and assign them to https://github.com/OpenZeppelin/openzeppelin-contracts/milestones[a milestone on GitHub]. During the next five weeks, they are worked on and fixed.
[[minor-releases]]
=== Release Candidates
Once the milestone is complete, we publish a feature-frozen release candidate. The purpose of the release candidate is to have a period where the community can review the new code before the actual release. If important problems are discovered, several more release candidates may be required. After a week of no more changes to the release candidate, the new version is published.
Before every release, we publish a feature-frozen release candidate. The purpose of the release candidate is to have a period where the community can review the new code before the actual release. If important problems are discovered, several more release candidates may be required. After a week of no more changes to the release candidate, the new version is published.
[[major-releases]]
=== Major Releases
@ -28,7 +26,7 @@ After several months or a year a new major release may come out. These are not s
On the https://github.com/OpenZeppelin/openzeppelin-contracts/releases/tag/v2.0.0[OpenZeppelin 2.0 release], we committed ourselves to keeping a stable API. We aim to more precisely define what we understand by _stable_ and _API_ here, so users of the library can understand these guarantees and be confident their project won't break unexpectedly.
In a nutshell, the API being stable means _if your project is working today, it will continue to do so_. New contracts and features will be added in minor releases, but only in a backwards compatible way.
In a nutshell, the API being stable means _if your project is working today, it will continue to do so after a minor upgrade_. New contracts and features will be added in minor releases, but only in a backwards compatible way.
[[versioning-scheme]]
=== Versioning Scheme
@ -45,7 +43,7 @@ If new functions are added to a contract, it will be in a backwards-compatible w
[[internal]]
==== `internal`
This extends not only to `external` and `public` functions, but also `internal` ones: many contracts are meant to be used by inheriting them (e.g. `Pausable`, `PullPayment`, the different `Roles` contracts), and are therefore used by calling these functions. Similarly, since all OpenZeppelin Contracts state variables are `private`, they can only be accessed this way (e.g. to create new `ERC20` tokens, instead of manually modifying `totalSupply` and `balances`, `_mint` should be called).
This extends not only to `external` and `public` functions, but also `internal` ones: many contracts are meant to be used by inheriting them (e.g. `Pausable`, `PullPayment`, `AccessControl`), and are therefore used by calling these functions. Similarly, since all OpenZeppelin Contracts state variables are `private`, they can only be accessed this way (e.g. to create new `ERC20` tokens, instead of manually modifying `totalSupply` and `balances`, `_mint` should be called).
`private` functions have no guarantees on their behavior, usage, or existence.
@ -54,13 +52,18 @@ Finally, sometimes language limitations will force us to e.g. make `internal` a
[[libraries]]
=== Libraries
Some of our Solidity libraries use ``struct``s to handle internal data that should not be accessed directly (e.g. `Roles`). There's an https://github.com/ethereum/solidity/issues/4637[open issue] in the Solidity repository requesting a language feature to prevent said access, but it looks like it won't be implemented any time soon. Because of this, we will use leading underscores and mark said `struct` s to make it clear to the user that its contents and layout are _not_ part of the API.
Some of our Solidity libraries use ``struct``s to handle internal data that should not be accessed directly (e.g. `Counter`). There's an https://github.com/ethereum/solidity/issues/4637[open issue] in the Solidity repository requesting a language feature to prevent said access, but it looks like it won't be implemented any time soon. Because of this, we will use leading underscores and mark said `struct` s to make it clear to the user that its contents and layout are _not_ part of the API.
[[events]]
=== Events
No events will be removed, and their arguments won't be changed in any way. New events may be added in later versions, and existing events may be emitted under new, reasonable circumstances (e.g. https://github.com/OpenZeppelin/openzeppelin-contracts/issues/707[from 2.1 on, `ERC20` also emits `Approval` on `transferFrom` calls]).
[[drafts]]
=== Drafts
Some contracts implement EIPs that are still in Draft status, recognizable by a file name beginning with `draft-`, such as `utils/cryptography/draft-EIP712.sol`. Due to their nature as drafts, the details of these contracts may change and we cannot guarantee their stability. Minor releases of OpenZeppelin Contracts may contain breaking changes for the contracts labelled as Drafts, which will be duly announced in the https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/CHANGELOG.md[changelog]. The EIPs included are used by projects in production and this may make them less likely to change significantly.
Francisco Giordano
4 years ago