diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..dfb6e8e
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,26 @@
+name: CI
+on:
+ push:
+ branches:
+ - main
+ pull_request:
+
+env:
+ FOUNDRY_PROFILE: ci
+
+jobs:
+ run-ci:
+ runs-on: ubuntu-latest
+ steps:
+ - uses: actions/checkout@v2
+
+ - name: Install Foundry
+ uses: foundry-rs/foundry-toolchain@v1
+ with:
+ version: nightly
+
+ - name: Install deps
+ run: forge install
+
+ - name: Run tests
+ run: forge test
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..757dc9e
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+out/
+cache/
+.vscode/
diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..e21df20
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,12 @@
+[submodule "lib/forge-std"]
+ path = lib/forge-std
+ url = https://github.com/foundry-rs/forge-std
+[submodule "lib/ds-token"]
+ path = lib/ds-token
+ url = https://github.com/dapphub/ds-token
+[submodule "lib/ds-note"]
+ path = lib/ds-note
+ url = https://github.com/dapphub/ds-note
+[submodule "lib/ds-auth"]
+ path = lib/ds-auth
+ url = https://github.com/dapphub/ds-auth
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..be3f7b2
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,661 @@
+ GNU AFFERO GENERAL PUBLIC LICENSE
+ Version 3, 19 November 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc.
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+ Preamble
+
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+software and other kinds of works, specifically designed to ensure
+cooperation with the community in the case of network server software.
+
+ The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works. By contrast,
+our General Public Licenses are intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
+software for all its users.
+
+ When we speak of free software, we are referring to freedom, not
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+ Developers that use our General Public Licenses protect your rights
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+ Later license versions may give you additional or different
+permissions. However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+ 15. Disclaimer of Warranty.
+
+ THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+ 16. Limitation of Liability.
+
+ IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+ 17. Interpretation of Sections 15 and 16.
+
+ If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+
+ Copyright (C)
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Affero General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU Affero General Public License for more details.
+
+ You should have received a copy of the GNU Affero General Public License
+ along with this program. If not, see .
+
+Also add information on how to contact you by electronic and paper mail.
+
+ If your software can interact with users remotely through a computer
+network, you should also make sure that it provides a way for users to
+get its source. For example, if your program is a web application, its
+interface could display a "Source" link that leads users to an archive
+of the code. There are many ways you could offer source, and different
+solutions will be better for different programs; see section 13 for the
+specific requirements.
+
+ You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU AGPL, see
+.
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..52d6e18
--- /dev/null
+++ b/README.md
@@ -0,0 +1,139 @@
+# Decentralized Summation System
+
+This repository contains the core smart contract code for the Decentralized
+Summation System (`dss`). This is a high level description of the system, assuming
+familiarity with the basic counting mechanics as described in the
+whitepaper.
+
+## System Diagram
+
+
+
+## Design Considerations
+
+- Client agnostic
+ - system doesn't care about the implementation of external contracts
+ - can operate entirely independently of other systems
+
+- Verifiable
+ - designed from the bottom up to be amenable to formal verification
+ - the core ICV and counter database makes *no* external calls and
+ contains *no* precision loss (i.e. no division)
+
+- Modular
+ - multi contract core system is made to be very adaptable to changing
+ requirements.
+ - allows for the addition of novel counter types (e.g. count-by-threes, fibonacci)
+
+## Usage
+
+See the test cases in [`dss.t.sol`](https://github.com/counterdao/dss/blob/aa7809965a314a5c8fdf7e6b5d39a92bf0901c3f/test/dss.t.sol#L76) for annotated examples that demonstrate how to interact with `dss` from your own contracts.
+
+## Sum — Counter Engine
+
+The `Sum` is the core Counter engine of `dss`. It stores Counters and tracks
+all the associated values. It also defines the rules by which Counters and values
+can be manipulated. The rules defined in the `Sum` are immutable, so in some
+sense, the rules in the `Sum` can be viewed as the constitution of `dss`.
+
+Within the `Sum` an `Inc` represents a stored ICV (Integer Counter Value). The
+attributes of an `Inc` are:
+- `net`: The counter value.
+- `tab`: The sum of all counter increments.
+- `tax`: The sum of all counter decrements.
+- `num`: Total number of counter operations, i.e. sum of increments, decrements, and resets.
+- `hop`: The counter's increment unit.
+
+Functions:
+- `boot`: Register a new Counter.
+- `zero`: Reset a Counter.
+- `frob`: General function for manipulating a Counter.
+ - `sinc`: "Sign of increment." 1 for increment, -1 for decrement.
+- `wish`: Check whether an address is allowed to modify another address's Counter.
+ - `hope`: enable `wish` for a pair of addresses.
+ - `nope`: disable `wish` for a pair of addresses.
+
+## Hitter — Increment module
+
+The `Hitter` is used to increment an initialized Counter.
+
+Functions:
+- `hit`: Increases a Counter's `net` and `tab` by one `hop`. Increments `num`.
+
+## Dipper — Decrement module
+
+The `Dipper` is used to decrement an initialized Counter.
+
+Functions:
+- `dip`: Decreases a Counter's `net` and `tax` by one `hop`. Increments `num`.
+
+## Nil — Reset module
+
+`Nil` is used to reset an initialized counter.
+
+Functions:
+- `nil`: Resets a Counter's `net`, `tab`, and `tax` to zero. Increments `num`.
+
+## Spy — Counter read module
+
+The `Spy` is used to read counter values.
+
+Functions:
+- `see`: Returns a Counter's `net`. View only function.
+
+## DSS — Protocol interface module
+
+The `DSS` module is an interface contract that composes other modules in
+the `dss` system and provides a unified interface to the protocol.
+
+Functions:
+- `build`: Create a new `DSSProxy` with this `DSS` module as its target implementation. Authorizes
+ `msg.sender` to interact with the proxy.
+ - `wit`: A `bytes32` salt for the `create2` constructor.
+ - `god`: Proxy owner address, authorized to update the implementation and manage `wards`.
+- `bless`: Authorize the core `dss` modules (`Use`, `Hitter`, `Dipper`, and `Nil`).
+- `use`: Create a new Counter.
+- `see`: Read a Counter value.
+- `hit`: Increment a Counter.
+- `dip`: Decrement a Counter.
+- `nil`: Reset a Counter.
+- `hope`: Authorize a module to manipulate a Counter.
+- `nope`: Revoke a module's authorization. This may be used to customize Counter
+ behavior, e.g. disabling decrements and resets.
+
+In most cases users should not interact directly with the `DSS` module, but instead use a `DSSProxy`.
+
+## DSSProxy — Execute DSS actions
+
+A `DSSProxy` is a transparent proxy contract that targets the `DSS` interface module as its
+implementation. This enables callers to execute DSS actions through a persistent identity.
+In most cases, users should create and interact with Counters through a `DSSProxy`.
+
+In the event of a protocol upgrade, the `DSSProxy` owner may choose to `upgrade` their proxy to
+target the latest `DSS` interface module.
+
+`DSSProxy` includes a flexible authorization mechanism that allows multiple callers to interact
+with a Counter through the proxy's persistent identity. This enables the creation of Counters
+that may be shared by multiple contracts simultaneously, or used by many different contracts
+over time.
+
+Functions:
+- `upgrade`: Set a new address as the target implementation. Only callable by the proxy `owner`
+- `rely`: Authorize an address to call the proxy and interact with a Counter.
+- `deny`: Revoke authorization from an address.
+
+## System parameters
+
+CTR token holders govern the core parameter of the DSS protocol, namely `One`.
+The value of `One` represents the global counter increment unit. Newly initialized Counters
+store the active `One` as their `hop` at creation time.
+
+**Note:** The value of `One` is a **critical** system parameter and **must be set carefully by governance**.
+An incorrect value of `One` may have unintended and far reaching consequences for
+the DSS protocol and the systems that depend on it.
+
+## Acknowledgments
+
+- [shrugs](https://github.com/shrugs), author of the one and only[`Counters.sol`](https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/Counters.sol).
+- [karmacoma](https://github.com/karmacoma-eth), for creating [`enterprise-counters`](https://github.com/karmacoma-eth/enterprise-counters) and putting me up to this.
+- [dapphub](https://github.com/dapphub) and [Maker](https://github.com/makerdao) for the greatest contracts of all time.
diff --git a/doc/dss-diagram.png b/doc/dss-diagram.png
new file mode 100644
index 0000000..0a4e8bb
Binary files /dev/null and b/doc/dss-diagram.png differ
diff --git a/foundry.toml b/foundry.toml
new file mode 100644
index 0000000..90a2b8c
--- /dev/null
+++ b/foundry.toml
@@ -0,0 +1,6 @@
+[profile.default]
+src = 'src'
+out = 'out'
+libs = ['lib']
+
+# See more config options https://github.com/foundry-rs/foundry/tree/master/config
diff --git a/lib/ds-auth b/lib/ds-auth
new file mode 160000
index 0000000..a51e7ca
--- /dev/null
+++ b/lib/ds-auth
@@ -0,0 +1 @@
+Subproject commit a51e7caa1f03eeffed66d67f3b38605e0f1f881d
diff --git a/lib/ds-note b/lib/ds-note
new file mode 160000
index 0000000..832591b
--- /dev/null
+++ b/lib/ds-note
@@ -0,0 +1 @@
+Subproject commit 832591b2d7dfb13dd513a72d0ff5a64c23b4e327
diff --git a/lib/ds-token b/lib/ds-token
new file mode 160000
index 0000000..16f187a
--- /dev/null
+++ b/lib/ds-token
@@ -0,0 +1 @@
+Subproject commit 16f187acc15dd839589be60173ad1ebd0716eb82
diff --git a/lib/forge-std b/lib/forge-std
new file mode 160000
index 0000000..27e14b7
--- /dev/null
+++ b/lib/forge-std
@@ -0,0 +1 @@
+Subproject commit 27e14b7f2448e5f5ac32719f51fe652aa0b0733e
diff --git a/src/dip.sol b/src/dip.sol
new file mode 100644
index 0000000..aa7576c
--- /dev/null
+++ b/src/dip.sol
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+/// dip.sol -- Counter decrement module
+
+// Copyright (C) 2022 Horsefacts
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see .
+
+pragma solidity ^0.8.15;
+
+interface SumLike {
+ function frob(address,int) external;
+}
+
+contract Dipper {
+ // --- Data ---
+ SumLike immutable public sum;
+
+ // --- Init ---
+ constructor(address sum_) {
+ sum = SumLike(sum_);
+ }
+
+ // --- Counter Decrement ---
+ function dip() external {
+ sum.frob(msg.sender, -1);
+ }
+}
diff --git a/src/dss.sol b/src/dss.sol
new file mode 100644
index 0000000..3e9af31
--- /dev/null
+++ b/src/dss.sol
@@ -0,0 +1,125 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+/// dss.sol -- Decentralized Summation System
+
+// Copyright (C) 2022 Horsefacts
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see .
+
+pragma solidity ^0.8.15;
+
+import {DSSProxy} from "./proxy/proxy.sol";
+
+interface DSSLike {
+ function use() external;
+ function see() external view returns (uint256);
+ function hit() external;
+ function dip() external;
+ function nil() external;
+ function hope(address) external;
+ function nope(address) external;
+ function bless() external;
+}
+
+interface SumLike {
+ function hope(address) external;
+ function nope(address) external;
+}
+
+interface UseLike {
+ function use() external;
+}
+
+interface SpyLike {
+ function see() external view returns (uint256);
+}
+
+interface HitterLike {
+ function hit() external;
+}
+
+interface DipperLike {
+ function dip() external;
+}
+
+interface NilLike {
+ function nil() external;
+}
+
+contract DSS {
+ // --- Data ---
+ SumLike immutable public _sum;
+ UseLike immutable public _use;
+ SpyLike immutable public _spy;
+ HitterLike immutable public _hitter;
+ DipperLike immutable public _dipper;
+ NilLike immutable public _nil;
+
+ // --- Init ---
+ constructor(
+ address sum_,
+ address use_,
+ address spy_,
+ address hitter_,
+ address dipper_,
+ address nil_)
+ {
+ _sum = SumLike(sum_); // Core ICV engine
+ _use = UseLike(use_); // Creation module
+ _spy = SpyLike(spy_); // Read module
+ _hitter = HitterLike(hitter_); // Increment module
+ _dipper = DipperLike(dipper_); // Decrement module
+ _nil = NilLike(nil_); // Reset module
+ }
+
+ // --- DSS Operations ---
+ function use() external {
+ _use.use();
+ }
+
+ function see() external view returns (uint256) {
+ return _spy.see();
+ }
+
+ function hit() external {
+ _hitter.hit();
+ }
+
+ function dip() external {
+ _dipper.dip();
+ }
+
+ function nil() external {
+ _nil.nil();
+ }
+
+ function hope(address usr) external {
+ _sum.hope(usr);
+ }
+
+ function nope(address usr) external {
+ _sum.nope(usr);
+ }
+
+ function bless() external {
+ _sum.hope(address(_use));
+ _sum.hope(address(_hitter));
+ _sum.hope(address(_dipper));
+ _sum.hope(address(_nil));
+ }
+
+ function build(bytes32 wit, address god) external returns (address proxy) {
+ proxy = address(new DSSProxy{ salt: wit }(address(this), msg.sender, god));
+ }
+}
diff --git a/src/gov/ctr.sol b/src/gov/ctr.sol
new file mode 100644
index 0000000..9def81b
--- /dev/null
+++ b/src/gov/ctr.sol
@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+/// ctr.sol -- Counter governance token
+
+// Copyright (C) 2022 Horsefacts
+// Copyright (C) 2015, 2016, 2017 DappHub, LLC
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see .
+
+pragma solidity >=0.4.23 <0.7.0;
+
+import {DSToken} from "ds-token/token.sol";
+
+contract CTR is DSToken {
+
+ constructor() DSToken("CTR") public {
+ setName("Counter");
+ mint(msg.sender, 1_000_000 ether);
+ }
+
+}
diff --git a/src/hit.sol b/src/hit.sol
new file mode 100644
index 0000000..5b3b617
--- /dev/null
+++ b/src/hit.sol
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+/// hit.sol -- Counter increment module
+
+// Copyright (C) 2022 Horsefacts
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see .
+
+pragma solidity ^0.8.15;
+
+interface SumLike {
+ function frob(address,int) external;
+}
+
+contract Hitter {
+ // --- Data ---
+ SumLike immutable public sum;
+
+ // --- Init ---
+ constructor(address sum_) {
+ sum = SumLike(sum_);
+ }
+
+ // --- Counter Increment ---
+ function hit() external {
+ sum.frob(msg.sender, 1);
+ }
+}
diff --git a/src/nil.sol b/src/nil.sol
new file mode 100644
index 0000000..416b9ac
--- /dev/null
+++ b/src/nil.sol
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+/// nil.sol -- Counter reset module
+
+// Copyright (C) 2022 Horsefacts
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see .
+
+pragma solidity ^0.8.15;
+
+interface SumLike {
+ function zero(address) external;
+}
+
+contract Nil {
+ // --- Data ---
+ SumLike immutable public sum;
+
+ // --- Init ---
+ constructor(address sum_) {
+ sum = SumLike(sum_);
+ }
+
+ // --- Counter Reset ---
+ function nil() external {
+ sum.zero(msg.sender);
+ }
+}
diff --git a/src/proxy/proxy.sol b/src/proxy/proxy.sol
new file mode 100644
index 0000000..d539f8a
--- /dev/null
+++ b/src/proxy/proxy.sol
@@ -0,0 +1,67 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+/// proxy.sol -- Execute DSS actions through the proxy's identity
+
+// Copyright (C) 2022 Horsefacts
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see .
+
+pragma solidity ^0.8.15;
+
+import {DSAuth} from "ds-auth/auth.sol";
+import {DSNote} from "ds-note/note.sol";
+
+contract DSSProxy is DSAuth, DSNote {
+ // --- Data ---
+ address public dss;
+
+ // --- Auth ---
+ mapping (address => uint) public wards;
+ function rely(address usr) external auth note { wards[usr] = 1; }
+ function deny(address usr) external auth note { wards[usr] = 0; }
+ modifier ward {
+ require(wards[msg.sender] == 1, "DSSProxy/not-authorized");
+ require(msg.sender != owner, "DSSProxy/owner-not-ward");
+ _;
+ }
+
+ // --- Init ---
+ constructor(address dss_, address usr, address god) {
+ dss = dss_;
+ wards[usr] = 1;
+ setOwner(god);
+ }
+
+ // --- Upgrade ---
+ function upgrade(address dss_) external auth note {
+ dss = dss_;
+ }
+
+ // --- Proxy ---
+ fallback() external ward note {
+ address _dss = dss;
+ assembly {
+ calldatacopy(0, 0, calldatasize())
+ let result := delegatecall(gas(), _dss, 0, calldatasize(), 0, 0)
+ returndatacopy(0, 0, returndatasize())
+ switch result
+ case 0 {
+ revert(0, returndatasize())
+ }
+ default {
+ return(0, returndatasize())
+ }
+ }
+ }
+}
diff --git a/src/spy.sol b/src/spy.sol
new file mode 100644
index 0000000..59e5470
--- /dev/null
+++ b/src/spy.sol
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+/// spy.sol -- Counter read module
+
+// Copyright (C) 2022 Horsefacts
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see .
+
+pragma solidity ^0.8.15;
+
+interface SumLike {
+ function incs(address) external view returns (uint256,uint256,uint256,uint256);
+}
+
+contract Spy {
+ // --- Data ---
+ SumLike immutable public sum;
+
+ // --- Init ---
+ constructor(address sum_) {
+ sum = SumLike(sum_);
+ }
+
+ // --- Counter Read ---
+ function see() external view returns (uint256 net) {
+ (net,,,) = sum.incs(msg.sender);
+ }
+}
diff --git a/src/sum.sol b/src/sum.sol
new file mode 100644
index 0000000..048fa6a
--- /dev/null
+++ b/src/sum.sol
@@ -0,0 +1,150 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+/// sum.sol -- Integer counter value (ICV) database
+
+// Copyright (C) 2022 Horsefacts
+// Copyright (C) 2018 Rain
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see .
+
+pragma solidity ^0.8.15;
+
+import {DSNote} from "ds-note/note.sol";
+
+contract Sum is DSNote {
+ // --- Auth ---
+ mapping (address => uint) public wards;
+ function rely(address usr) external auth note { require(live == 1, "Sum/not-live"); wards[usr] = 1; }
+ function deny(address usr) external auth note { require(live == 1, "Sum/not-live"); wards[usr] = 0; }
+ modifier auth {
+ require(wards[msg.sender] == 1, "Sum/not-authorized");
+ _;
+ }
+
+ mapping(address => mapping (address => uint)) public can;
+ function hope(address usr) external note { can[msg.sender][usr] = 1; }
+ function nope(address usr) external note { can[msg.sender][usr] = 0; }
+ function wish(address bit, address usr) internal view returns (bool) {
+ return either(bit == usr, can[bit][usr] == 1);
+ }
+
+ // --- Data ---
+ struct Inc {
+ uint256 net; // Net counter value
+ uint256 tab; // Sum of increments
+ uint256 tax; // Sum of decrements
+ uint256 num; // Total counter operations
+ uint256 hop; // Counter increment unit
+ }
+
+ mapping (address => Inc) public incs;
+
+ uint256 public One; // Global increment parameter
+ uint256 public live; // Active Flag
+
+ // --- Init ---
+ constructor() {
+ wards[msg.sender] = 1;
+ One = 1;
+ live = 1;
+ }
+
+ // --- Math ---
+ function add(uint x, uint y) internal pure returns (uint z) {
+ require((z = x + y) >= x);
+ }
+ function sub(uint x, uint y) internal pure returns (uint z) {
+ require((z = x - y) <= x);
+ }
+
+ // --- Administration ---
+ function file(bytes32 what, uint data) external note auth {
+ require(live == 1, "Sum/not-live");
+ if (what == "One") {
+ if (data != 0) One = data;
+ else revert("Sum/not-allowed-one");
+ }
+ else revert("Sum/file-unrecognized-param");
+ }
+ function cage() external note auth {
+ live = 0;
+ }
+
+ function either(bool x, bool y) internal pure returns (bool z) {
+ assembly{ z := or(x, y)}
+ }
+
+ // --- ICV Creation ---
+ function boot(address i) external note {
+ // system is live
+ require(live == 1, "Sum/not-live");
+
+ // caller is allowed
+ require(wish(i, msg.sender), "Sum/not-allowed");
+
+ // inc has not been initialised
+ require(incs[i].hop == 0, "Sum/inc-already-init");
+
+ incs[i].hop = One;
+ }
+
+ // --- ICV Reset ---
+ function zero(address i) external note {
+ // system is live
+ require(live == 1, "Sum/not-live");
+
+ // caller is allowed
+ require(wish(i, msg.sender), "Sum/not-allowed");
+
+ Inc memory inc = incs[i];
+ // inc has been initialised
+ require(inc.hop != 0, "Sum/inc-not-init");
+
+ inc.net = 0;
+ inc.tab = 0;
+ inc.tax = 0;
+ inc.num = add(inc.num, 1);
+ incs[i] = inc;
+ }
+
+ // --- ICV Manipulation ---
+ function frob(address i, int sinc) external note {
+ // system is live
+ require(live == 1, "Sum/not-live");
+
+ // caller is allowed
+ require(wish(i, msg.sender), "Sum/not-allowed");
+
+ // sinc is allowed
+ require(either(sinc == 1, sinc == -1), "Sum/not-allowed-sinc");
+
+ Inc memory inc = incs[i];
+ // inc has been initialised
+ require(inc.hop != 0, "Sum/inc-not-init");
+
+ // hop is safe
+ require(either(sinc == 1, inc.net >= inc.hop), "Sum/not-safe-hop");
+
+ if (sinc == 1) {
+ inc.net = add(inc.net, inc.hop);
+ inc.tab = add(inc.tab, inc.hop);
+ }
+ if (sinc == -1) {
+ inc.net = sub(inc.net, inc.hop);
+ inc.tax = add(inc.tax, inc.hop);
+ }
+ inc.num = add(inc.num, 1);
+ incs[i] = inc;
+ }
+}
diff --git a/src/use.sol b/src/use.sol
new file mode 100644
index 0000000..de965fd
--- /dev/null
+++ b/src/use.sol
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+/// use.sol -- Counter creation module
+
+// Copyright (C) 2022 Horsefacts
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see .
+
+pragma solidity ^0.8.15;
+
+interface SumLike {
+ function boot(address) external;
+}
+
+contract Use {
+ // --- Data ---
+ SumLike immutable public sum;
+
+ // --- Init ---
+ constructor(address sum_) {
+ sum = SumLike(sum_);
+ }
+
+ // --- Counter Read ---
+ function use() external{
+ sum.boot(msg.sender);
+ }
+}
diff --git a/test/dip.t.sol b/test/dip.t.sol
new file mode 100644
index 0000000..b4382ef
--- /dev/null
+++ b/test/dip.t.sol
@@ -0,0 +1,102 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+// Copyright (C) 2022 Horsefacts
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see .
+
+pragma solidity ^0.8.13;
+
+import "forge-std/Test.sol";
+
+import {Sum} from "../src/sum.sol";
+import {Dipper} from "../src/dip.sol";
+
+contract TestDip is Test {
+ Sum internal sum;
+ Dipper internal dipper;
+
+ address me = address(this);
+
+ function setUp() public {
+ sum = new Sum();
+ dipper = new Dipper(address(sum));
+
+ sum.boot(me);
+ sum.hope(address(dipper));
+ }
+
+ function test_dip() public {
+ sum.frob(me, 1);
+ sum.frob(me, 1);
+ sum.frob(me, 1);
+ sum.frob(me, 1);
+ sum.frob(me, 1);
+
+ (uint256 net, uint256 tab, uint256 tax, uint256 num, uint256 hop) = sum.incs(me);
+
+ assertEq(net, 5);
+ assertEq(tab, 5);
+ assertEq(tax, 0);
+ assertEq(num, 5);
+ assertEq(hop, 1);
+
+ dipper.dip();
+ (net, tab, tax, num, hop) = sum.incs(me);
+
+ assertEq(net, 4);
+ assertEq(tab, 5);
+ assertEq(tax, 1);
+ assertEq(num, 6);
+ assertEq(hop, 1);
+
+ dipper.dip();
+ (net, tab, tax, num, hop) = sum.incs(me);
+
+ assertEq(net, 3);
+ assertEq(tab, 5);
+ assertEq(tax, 2);
+ assertEq(num, 7);
+ assertEq(hop, 1);
+
+ dipper.dip();
+ (net, tab, tax, num, hop) = sum.incs(me);
+
+ assertEq(net, 2);
+ assertEq(tab, 5);
+ assertEq(tax, 3);
+ assertEq(num, 8);
+ assertEq(hop, 1);
+
+ dipper.dip();
+ (net, tab, tax, num, hop) = sum.incs(me);
+
+ assertEq(net, 1);
+ assertEq(tab, 5);
+ assertEq(tax, 4);
+ assertEq(num, 9);
+ assertEq(hop, 1);
+
+ dipper.dip();
+ (net, tab, tax, num, hop) = sum.incs(me);
+
+ assertEq(net, 0);
+ assertEq(tab, 5);
+ assertEq(tax, 5);
+ assertEq(num, 10);
+ assertEq(hop, 1);
+
+ vm.expectRevert("Sum/not-safe-hop");
+ dipper.dip();
+ }
+}
diff --git a/test/dss.t.sol b/test/dss.t.sol
new file mode 100644
index 0000000..da36b39
--- /dev/null
+++ b/test/dss.t.sol
@@ -0,0 +1,484 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+// Copyright (C) 2022 Horsefacts
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see .
+
+pragma solidity ^0.8.13;
+
+import "forge-std/Test.sol";
+
+import {DSS, DSSProxy, DSSLike} from "../src/dss.sol";
+import {Sum} from "../src/sum.sol";
+import {Use} from "../src/use.sol";
+import {Hitter} from "../src/hit.sol";
+import {Dipper} from "../src/dip.sol";
+import {Nil} from "../src/nil.sol";
+import {Spy} from "../src/spy.sol";
+
+contract DSSTest is Test {
+ Sum internal sum;
+ Use internal use;
+ Nil internal nil;
+ Spy internal spy;
+
+ Hitter internal hitter;
+ Dipper internal dipper;
+
+ DSS internal dss;
+
+ address me = address(this);
+ address guy = mkaddr('guy');
+ address alice = mkaddr('alice');
+ address bob = mkaddr('bob');
+ address carol = mkaddr('carol');
+ address dan = mkaddr('dan');
+ address eve = mkaddr('eve');
+
+ function mkaddr(string memory name) public returns (address addr) {
+ addr = address(uint160(uint256(keccak256(abi.encodePacked(name)))));
+ vm.label(addr, name);
+ }
+
+ function setUp() public {
+ vm.startPrank(guy);
+ sum = new Sum();
+ use = new Use(address(sum));
+ nil = new Nil(address(sum));
+ spy = new Spy(address(sum));
+
+ hitter = new Hitter(address(sum));
+ dipper = new Dipper(address(sum));
+
+ dss = new DSS(
+ address(sum),
+ address(use),
+ address(spy),
+ address(hitter),
+ address(dipper),
+ address(nil)
+ );
+ vm.stopPrank();
+ }
+}
+
+contract Examples is DSSTest {
+
+ function test_example_create_basic_counter() public {
+ // This example demonstrates creating a
+ // basic counter.
+
+ // Deploy a DSSProxy with Bob as admin
+ address proxy = dss.build("", bob);
+
+ // Our current address is authorized
+ // to call the proxy and interact with
+ // the DSS protocol. We can now create
+ // a Counter.
+ DSSLike inc = DSSLike(proxy);
+
+ // First we call bless to authorize
+ // core DSS modules to call the Sum
+ // on our behalf.
+ inc.bless();
+
+ // Next, we create a new counter.
+ inc.use();
+
+ // Our counter starts at zero.
+ assertEq(inc.see(), 0);
+
+ // We can increment:
+ inc.hit();
+ inc.hit();
+ inc.hit();
+ assertEq(inc.see(), 3);
+
+ // And decrement:
+ inc.dip();
+ assertEq(inc.see(), 2);
+
+ // As well as reset to zero:
+ inc.nil();
+ assertEq(inc.see(), 0);
+ }
+
+ function test_example_create_custom_counter_up_only() public {
+ // This example demonstrates creating a
+ // custom counter that cannot be decremnted
+ // or reset.
+
+ // Deploy a DSSProxy with Bob as admin
+ address proxy = dss.build("", bob);
+
+ // Our current address is authorized
+ // to call the proxy and interact with
+ // the DSS protocol. We can now create
+ // a Counter.
+ DSSLike inc = DSSLike(proxy);
+
+ // First we call bless to authorize
+ // core DSS modules to call the Sum
+ // on our behalf.
+ inc.bless();
+
+ // Disable the decrement module
+ inc.nope(address(dipper));
+
+ // Disable the reset module
+ inc.nope(address(nil));
+
+ // Create a new counter.
+ inc.use();
+
+ // Our counter starts at zero.
+ assertEq(inc.see(), 0);
+
+ // We can increment:
+ inc.hit();
+ inc.hit();
+ inc.hit();
+ assertEq(inc.see(), 3);
+
+ // We cannot decrement:
+ vm.expectRevert('Sum/not-allowed');
+ inc.dip();
+
+ // Nor reset to zero:
+ vm.expectRevert('Sum/not-allowed');
+ inc.nil();
+ }
+
+ function test_example_proxy_authorization() public {
+ // This example demonstrates proxy auth.
+ // The proxy owner may authorize multiple
+ // callers to interact with DSS.
+
+ // Deploy a DSSProxy with Bob as admin
+ address proxy = dss.build("", bob);
+
+ // Our current address is authorized
+ // to call the proxy and interact with
+ // the DSS protocol. We can now create
+ // a Counter.
+ DSSLike inc = DSSLike(proxy);
+
+ // First we call bless to authorize
+ // core DSS modules to call the Sum
+ // on our behalf.
+ inc.bless();
+
+ // Next, we create a new counter.
+ inc.use();
+
+ // Our counter starts at zero.
+ assertEq(inc.see(), 0);
+
+ // We can increment:
+ inc.hit();
+ assertEq(inc.see(), 1);
+
+ // As the owner of our DSSProxy, Bob
+ // can authorize other addressess to
+ // interact with our Counter. However,
+ // he must use a DSSProxy interface to
+ // access the authorization functions.
+ DSSProxy admin = DSSProxy(proxy);
+
+ // Bob grants access to Alice's address
+ vm.prank(bob);
+ admin.rely(alice);
+
+ // Now Alice may also increment our Counter.
+ vm.prank(alice);
+ inc.hit();
+ assertEq(inc.see(), 2);
+
+ // This flexible multi-owner authentication
+ // system can enable us to create immutable but
+ // modular contracts that interact with our
+ // Counter.
+ }
+}
+
+contract TestDSS is DSSTest {
+
+ function test_dss() public {
+ // Authorize core modules
+ dss.bless();
+
+ // Create a new Counter
+ dss.use();
+
+ // Read counter
+ assertEq(dss.see(), 0);
+
+ // Increment counter
+ dss.hit();
+ assertEq(dss.see(), 1);
+
+ dss.hit();
+ assertEq(dss.see(), 2);
+
+ dss.hit();
+ assertEq(dss.see(), 3);
+
+ // Reset counter
+ dss.nil();
+ assertEq(dss.see(), 0);
+
+ // Increment counter
+ dss.hit();
+ assertEq(dss.see(), 1);
+
+ dss.hit();
+ assertEq(dss.see(), 2);
+
+ // Decrement counter
+ dss.dip();
+ assertEq(dss.see(), 1);
+
+ dss.dip();
+ assertEq(dss.see(), 0);
+
+ vm.expectRevert("Sum/not-safe-hop");
+ dss.dip();
+ }
+
+ function test_nope_hitter() public {
+ // Authorize core modules
+ dss.bless();
+
+ // Create a new Counter
+ dss.use();
+
+ // Revoke Hitter
+ dss.nope(address(hitter));
+
+ vm.expectRevert("Sum/not-allowed");
+ dss.hit();
+ }
+
+ function test_nope_dipper() public {
+ // Authorize core modules
+ dss.bless();
+
+ // Create a new Counter
+ dss.use();
+
+ // Revoke Hitter
+ dss.nope(address(dipper));
+
+ vm.expectRevert("Sum/not-allowed");
+ dss.dip();
+ }
+
+ function test_nope_nil() public {
+ // Authorize core modules
+ dss.bless();
+
+ // Create a new Counter
+ dss.use();
+
+ // Revoke Hitter
+ dss.nope(address(nil));
+
+ vm.expectRevert("Sum/not-allowed");
+ dss.nil();
+ }
+
+ function test_dss_proxy() public {
+ // Alice is proxy usr, Bob is proxy god
+ vm.startPrank(alice);
+ address proxyAddr = dss.build("", bob);
+ DSSProxy proxy = DSSProxy(proxyAddr);
+ DSSLike inc = DSSLike(address(proxy));
+ vm.stopPrank();
+
+ // Bob cannot call fallback
+ vm.prank(bob);
+ vm.expectRevert("DSSProxy/not-authorized");
+ inc.bless();
+
+ // Eve cannot call fallback
+ vm.prank(eve);
+ vm.expectRevert("DSSProxy/not-authorized");
+ inc.bless();
+
+ // Alice can call fallback as ward
+ vm.startPrank(alice);
+
+ // Authorize core modules
+ inc.bless();
+
+ // Create a new Counter
+ inc.use();
+
+ // Read counter
+ assertEq(inc.see(), 0);
+
+ // Increment counter
+ inc.hit();
+ assertEq(inc.see(), 1);
+
+ inc.hit();
+ assertEq(inc.see(), 2);
+
+ inc.hit();
+ assertEq(inc.see(), 3);
+
+ // Reset counter
+ inc.nil();
+ assertEq(inc.see(), 0);
+
+ // Increment counter
+ inc.hit();
+ assertEq(inc.see(), 1);
+
+ inc.hit();
+ assertEq(inc.see(), 2);
+
+ // Decrement counter
+ inc.dip();
+ assertEq(inc.see(), 1);
+
+ inc.dip();
+ assertEq(inc.see(), 0);
+
+ vm.expectRevert("Sum/not-safe-hop");
+ inc.dip();
+
+ vm.stopPrank();
+
+ // Deploy new DSS module
+ DSS upgraded = new DSS(
+ address(sum),
+ address(use),
+ address(spy),
+ address(hitter),
+ address(dipper),
+ address(nil)
+ );
+
+ // Alice cannot upgrade
+ vm.expectRevert("ds-auth-unauthorized");
+ vm.prank(alice);
+ proxy.upgrade(address(upgraded));
+
+ // Eve cannot upgrade
+ vm.expectRevert("ds-auth-unauthorized");
+ vm.prank(eve);
+ proxy.upgrade(address(upgraded));
+
+ // Bob can upgrade
+ vm.prank(bob);
+ proxy.upgrade(address(upgraded));
+
+ // Allow access
+
+ // Alice cannot add ward
+ vm.expectRevert("ds-auth-unauthorized");
+ vm.prank(alice);
+ proxy.rely(carol);
+
+ // Eve cannot upgrade
+ vm.expectRevert("ds-auth-unauthorized");
+ vm.prank(eve);
+ proxy.rely(carol);
+
+ // Bob can add ward
+ vm.prank(bob);
+ proxy.rely(carol);
+
+ // Carol can interact with counter
+ vm.startPrank(carol);
+ assertEq(inc.see(), 0);
+
+ inc.hit();
+ assertEq(inc.see(), 1);
+
+ inc.nil();
+ assertEq(inc.see(), 0);
+
+ inc.hit();
+ assertEq(inc.see(), 1);
+
+ inc.dip();
+ assertEq(inc.see(), 0);
+
+ vm.stopPrank();
+
+ // Alice can interact with counter
+ vm.startPrank(alice);
+ assertEq(inc.see(), 0);
+
+ inc.hit();
+ assertEq(inc.see(), 1);
+
+ vm.stopPrank();
+
+ // Eve cannot interact with counter
+ vm.expectRevert("DSSProxy/not-authorized");
+ vm.prank(eve);
+ inc.hit();
+
+ // Revoke Alice's access
+ vm.prank(bob);
+ proxy.deny(alice);
+
+ // Alice cannot interact with counter
+ vm.expectRevert("DSSProxy/not-authorized");
+ vm.prank(alice);
+ inc.hit();
+
+ // Carol can still interact with counter
+ vm.startPrank(carol);
+
+ inc.hit();
+ assertEq(inc.see(), 2);
+
+ vm.stopPrank();
+
+ // Proxy ownership transfer
+
+ // Alice cannot transfer
+ vm.prank(alice);
+ vm.expectRevert("ds-auth-unauthorized");
+ proxy.setOwner(dan);
+
+ // Eve cannot transfer
+ vm.prank(eve);
+ vm.expectRevert("ds-auth-unauthorized");
+ proxy.setOwner(dan);
+
+ // Bob can transfer
+ vm.prank(bob);
+ proxy.setOwner(dan);
+
+ // Dan is now owner
+ assertEq(proxy.owner(), dan);
+
+ // Bob cannot transfer
+ vm.prank(bob);
+ vm.expectRevert("ds-auth-unauthorized");
+ proxy.setOwner(bob);
+
+ // Dan can transfer
+ vm.prank(dan);
+ proxy.setOwner(bob);
+
+ // Bob is now owner
+ assertEq(proxy.owner(), bob);
+ }
+}
diff --git a/test/gov/ctr.t.sol b/test/gov/ctr.t.sol
new file mode 100644
index 0000000..6c32337
--- /dev/null
+++ b/test/gov/ctr.t.sol
@@ -0,0 +1,46 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+// Copyright (C) 2022 Horsefacts
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see .
+
+pragma solidity >=0.4.23 <0.7.0;
+
+import "forge-std/Test.sol";
+
+import {CTR} from "../../src/gov/ctr.sol";
+
+contract TestCTR is Test {
+ CTR internal ctr;
+
+ address me = address(this);
+
+ function setUp() public {
+ ctr = new CTR();
+ }
+
+ function test_symbol() public {
+ assertEq(ctr.symbol(), "CTR");
+ }
+
+ function test_name() public {
+ assertEq(ctr.name(), "Counter");
+ }
+
+ function test_supply() public {
+ assertEq(ctr.balanceOf(me), ctr.totalSupply());
+ assertEq(ctr.totalSupply(), 1_000_000 ether);
+ }
+
+}
diff --git a/test/hit.t.sol b/test/hit.t.sol
new file mode 100644
index 0000000..0354653
--- /dev/null
+++ b/test/hit.t.sol
@@ -0,0 +1,67 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+// Copyright (C) 2022 Horsefacts
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see .
+
+pragma solidity ^0.8.13;
+
+import "forge-std/Test.sol";
+
+import {Sum} from "../src/sum.sol";
+import {Hitter} from "../src/hit.sol";
+
+contract TestHit is Test {
+ Sum internal sum;
+ Hitter internal hitter;
+
+ address me = address(this);
+
+ function setUp() public {
+ sum = new Sum();
+ hitter = new Hitter(address(sum));
+
+ sum.boot(me);
+ sum.hope(address(hitter));
+ }
+
+ function test_hit() public {
+ hitter.hit();
+ (uint256 net, uint256 tab, uint256 tax, uint256 num, uint256 hop) = sum.incs(me);
+
+ assertEq(net, 1);
+ assertEq(tab, 1);
+ assertEq(tax, 0);
+ assertEq(num, 1);
+ assertEq(hop, 1);
+
+ hitter.hit();
+ (net, tab, tax, num, hop) = sum.incs(me);
+
+ assertEq(net, 2);
+ assertEq(tab, 2);
+ assertEq(tax, 0);
+ assertEq(num, 2);
+ assertEq(hop, 1);
+
+ hitter.hit();
+ (net, tab, tax, num, hop) = sum.incs(me);
+
+ assertEq(net, 3);
+ assertEq(tab, 3);
+ assertEq(tax, 0);
+ assertEq(num, 3);
+ assertEq(hop, 1);
+ }
+}
diff --git a/test/nil.t.sol b/test/nil.t.sol
new file mode 100644
index 0000000..d421ce5
--- /dev/null
+++ b/test/nil.t.sol
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+// Copyright (C) 2022 Horsefacts
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see .
+
+pragma solidity ^0.8.13;
+
+import "forge-std/Test.sol";
+
+import {Sum} from "../src/sum.sol";
+import {Nil} from "../src/nil.sol";
+
+contract TestNil is Test {
+ Sum internal sum;
+ Nil internal nil;
+
+ address me = address(this);
+
+ function setUp() public {
+ sum = new Sum();
+ nil = new Nil(address(sum));
+
+ sum.boot(me);
+ sum.hope(address(nil));
+ }
+
+ function test_nil() public {
+ sum.frob(me, 1);
+ sum.frob(me, 1);
+ sum.frob(me, 1);
+ sum.frob(me, 1);
+ sum.frob(me, 1);
+
+ (uint256 net, uint256 tab, uint256 tax, uint256 num, uint256 hop) = sum.incs(me);
+
+ assertEq(net, 5);
+ assertEq(tab, 5);
+ assertEq(tax, 0);
+ assertEq(num, 5);
+ assertEq(hop, 1);
+
+ nil.nil();
+ (net, tab, tax, num, hop) = sum.incs(me);
+
+ assertEq(net, 0);
+ assertEq(tab, 0);
+ assertEq(tax, 0);
+ assertEq(num, 6);
+ assertEq(hop, 1);
+ }
+}
diff --git a/test/spy.t.sol b/test/spy.t.sol
new file mode 100644
index 0000000..20c51a1
--- /dev/null
+++ b/test/spy.t.sol
@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+// Copyright (C) 2022 Horsefacts
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see .
+
+pragma solidity ^0.8.13;
+
+import "forge-std/Test.sol";
+
+import {Sum} from "../src/sum.sol";
+import {Spy} from "../src/spy.sol";
+
+contract TestNil is Test {
+ Sum internal sum;
+ Spy internal spy;
+
+ address me = address(this);
+
+ function setUp() public {
+ sum = new Sum();
+ spy = new Spy(address(sum));
+
+ sum.boot(me);
+ }
+
+ function test_spy() public {
+ sum.frob(me, 1);
+ assertEq(spy.see(), 1);
+
+ sum.frob(me, 1);
+ assertEq(spy.see(), 2);
+
+ sum.frob(me, 1);
+ assertEq(spy.see(), 3);
+
+ sum.frob(me, -1);
+ assertEq(spy.see(), 2);
+
+ sum.frob(me, -1);
+ assertEq(spy.see(), 1);
+
+ sum.frob(me, -1);
+ assertEq(spy.see(), 0);
+ }
+}
diff --git a/test/sum.t.sol b/test/sum.t.sol
new file mode 100644
index 0000000..ce1c073
--- /dev/null
+++ b/test/sum.t.sol
@@ -0,0 +1,260 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+// Copyright (C) 2022 Horsefacts
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see .
+
+pragma solidity ^0.8.13;
+
+import "forge-std/Test.sol";
+
+import {Sum} from "../src/sum.sol";
+
+contract TestSum is Test {
+ Sum internal sum;
+
+ address me = address(this);
+
+ function setUp() public {
+ sum = new Sum();
+ }
+
+ function test_boot() public {
+ sum.boot(me);
+
+ (uint256 net, uint256 tab, uint256 tax, uint256 num, uint256 hop) = sum.incs(me);
+
+ assertEq(net, 0);
+ assertEq(tab, 0);
+ assertEq(tax, 0);
+ assertEq(num, 0);
+ assertEq(hop, 1);
+ }
+
+ function test_boot_already_init() public {
+ sum.boot(me);
+
+ vm.expectRevert("Sum/inc-already-init");
+ sum.boot(me);
+ }
+
+ function test_frob_inc() public {
+ sum.boot(me);
+
+ sum.frob(me, 1);
+ (uint256 net, uint256 tab, uint256 tax, uint256 num, uint256 hop) = sum.incs(me);
+
+ assertEq(net, 1);
+ assertEq(tab, 1);
+ assertEq(tax, 0);
+ assertEq(num, 1);
+ assertEq(hop, 1);
+
+ sum.frob(me, 1);
+ (net, tab, tax, num, hop) = sum.incs(me);
+
+ assertEq(net, 2);
+ assertEq(tab, 2);
+ assertEq(tax, 0);
+ assertEq(num, 2);
+ assertEq(hop, 1);
+
+ sum.frob(me, 1);
+ (net, tab, tax, num, hop) = sum.incs(me);
+
+ assertEq(net, 3);
+ assertEq(tab, 3);
+ assertEq(tax, 0);
+ assertEq(num, 3);
+ assertEq(hop, 1);
+ }
+
+ function test_frob_dec_underflow() public {
+ sum.boot(me);
+
+ vm.expectRevert("Sum/not-safe-hop");
+ sum.frob(me, -1);
+ }
+
+ function test_frob_dec() public {
+ sum.boot(me);
+
+ sum.frob(me, 1);
+ sum.frob(me, 1);
+ sum.frob(me, 1);
+ sum.frob(me, 1);
+ sum.frob(me, 1);
+
+ (uint256 net, uint256 tab, uint256 tax, uint256 num, uint256 hop) = sum.incs(me);
+
+ assertEq(net, 5);
+ assertEq(tab, 5);
+ assertEq(tax, 0);
+ assertEq(num, 5);
+ assertEq(hop, 1);
+
+ sum.frob(me, -1);
+ (net, tab, tax, num, hop) = sum.incs(me);
+
+ assertEq(net, 4);
+ assertEq(tab, 5);
+ assertEq(tax, 1);
+ assertEq(num, 6);
+ assertEq(hop, 1);
+
+ sum.frob(me, -1);
+ (net, tab, tax, num, hop) = sum.incs(me);
+
+ assertEq(net, 3);
+ assertEq(tab, 5);
+ assertEq(tax, 2);
+ assertEq(num, 7);
+ assertEq(hop, 1);
+
+ sum.frob(me, -1);
+ (net, tab, tax, num, hop) = sum.incs(me);
+
+ assertEq(net, 2);
+ assertEq(tab, 5);
+ assertEq(tax, 3);
+ assertEq(num, 8);
+ assertEq(hop, 1);
+
+ sum.frob(me, -1);
+ (net, tab, tax, num, hop) = sum.incs(me);
+
+ assertEq(net, 1);
+ assertEq(tab, 5);
+ assertEq(tax, 4);
+ assertEq(num, 9);
+ assertEq(hop, 1);
+
+ sum.frob(me, -1);
+ (net, tab, tax, num, hop) = sum.incs(me);
+
+ assertEq(net, 0);
+ assertEq(tab, 5);
+ assertEq(tax, 5);
+ assertEq(num, 10);
+ assertEq(hop, 1);
+
+ vm.expectRevert("Sum/not-safe-hop");
+ sum.frob(me, -1);
+ }
+
+ function test_frob_uninitialized_inc() public {
+ vm.expectRevert("Sum/inc-not-init");
+ sum.frob(me, 1);
+ }
+
+ function test_frob_invalid_sinc(int sinc) public {
+ vm.assume(sinc != 1);
+ vm.assume(sinc != -1);
+
+ vm.expectRevert("Sum/not-allowed-sinc");
+ sum.frob(me, sinc);
+ }
+
+ function test_zero() public {
+ sum.boot(me);
+
+ sum.frob(me, 1);
+ (uint256 net, uint256 tab, uint256 tax, uint256 num, uint256 hop) = sum.incs(me);
+
+ assertEq(net, 1);
+ assertEq(tab, 1);
+ assertEq(tax, 0);
+ assertEq(num, 1);
+ assertEq(hop, 1);
+
+ sum.zero(me);
+ (net, tab, tax, num, hop) = sum.incs(me);
+
+ assertEq(net, 0);
+ assertEq(tab, 0);
+ assertEq(tax, 0);
+ assertEq(num, 2);
+ assertEq(hop, 1);
+ }
+
+ function test_file_one() public {
+ sum.file("One", 2);
+
+ sum.boot(me);
+ sum.frob(me, 1);
+ (uint256 net, uint256 tab, uint256 tax, uint256 num, uint256 hop) = sum.incs(me);
+
+ assertEq(net, 2);
+ assertEq(tab, 2);
+ assertEq(tax, 0);
+ assertEq(num, 1);
+ assertEq(hop, 2);
+ }
+
+ function test_file_invalid_one() public {
+ vm.expectRevert("Sum/not-allowed-one");
+ sum.file("One", 0);
+ }
+
+ function test_file_unrecognized_param() public {
+ vm.expectRevert("Sum/file-unrecognized-param");
+ sum.file("Wat", 0);
+ }
+
+ function test_cage() public {
+ sum.boot(me);
+
+ sum.cage();
+
+ vm.expectRevert("Sum/not-live");
+ sum.file("One", 1);
+
+ vm.expectRevert("Sum/not-live");
+ sum.boot(me);
+
+ vm.expectRevert("Sum/not-live");
+ sum.zero(me);
+
+ vm.expectRevert("Sum/not-live");
+ sum.frob(me, 1);
+
+ vm.expectRevert("Sum/not-live");
+ sum.rely(me);
+
+ vm.expectRevert("Sum/not-live");
+ sum.deny(me);
+ }
+
+ function test_rely_deny() public {
+ address guy = address(1);
+
+ sum.rely(guy);
+ assertEq(sum.wards(me), 1);
+
+ sum.deny(guy);
+ assertEq(sum.wards(guy), 0);
+ }
+
+ function test_deny_unauthorized() public {
+ sum.deny(me);
+
+ vm.expectRevert("Sum/not-authorized");
+ sum.rely(me);
+ }
+
+ function test_default_parameters() public {
+ assertEq(sum.One(), 1);
+ assertEq(sum.live(), 1);
+ }
+}
diff --git a/test/use.t.sol b/test/use.t.sol
new file mode 100644
index 0000000..2b190bb
--- /dev/null
+++ b/test/use.t.sol
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+// Copyright (C) 2022 Horsefacts
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see .
+
+pragma solidity ^0.8.13;
+
+import "forge-std/Test.sol";
+
+import {Sum} from "../src/sum.sol";
+import {Use} from "../src/use.sol";
+
+contract TestUse is Test {
+ Sum internal sum;
+ Use internal use;
+
+ address me = address(this);
+
+ function setUp() public {
+ sum = new Sum();
+ use = new Use(address(sum));
+
+ sum.hope(address(use));
+ }
+
+ function test_use() public {
+ use.use();
+
+ sum.frob(me, 1);
+ (uint256 net, uint256 tab, uint256 tax, uint256 num, uint256 hop) = sum.incs(me);
+
+ assertEq(net, 1);
+ assertEq(tab, 1);
+ assertEq(tax, 0);
+ assertEq(num, 1);
+ assertEq(hop, 1);
+ }
+}