feat(plugins): add Babel Fees plugin

jest.config.ts

@@ -5,5 +5,5 @@ export default {
   testEnvironment: "node",
   maxWorkers: 1, // this limit is being used to circumvent this issue https://github.com/facebook/jest/issues/11617
   preset: "ts-jest",
-  roots: ["./packages"]
+  roots: ["./packages", "./plugins"]
 };

packages/common/src/index.ts

@@ -1,3 +1,2 @@
 export * from "./utils";
 export * from "./types";
-export * from "./constants";

plugins/babel-fees/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2022 capt-nemo429
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

plugins/babel-fees/README.md

@@ -0,0 +1,3 @@
+# @fleet-sdk/babel-fees-plugin [![License](https://badgen.net/github/license/fleet-sdk/fleet/)](https://github.com/fleet-sdk/fleet/blob/master/LICENSE) [![npm](https://badgen.net/npm/v/@fleet-sdk/babel-fees-plugin)](https://www.npmjs.com/package/@fleet-sdk/babel-fees-plugin)
+
+Babel Fees utilities and plugin for Fleet SDK.

plugins/babel-fees/jest.config.ts

@@ -0,0 +1,20 @@
+export default {
+  collectCoverageFrom: ["./src/**/*.ts", "!./src/**/I[A-Z]*.ts", "!./src/**/index.ts"],
+  coveragePathIgnorePatterns: ["/node_modules/", "./src/tests", "./src/types"],
+  coverageDirectory: "./coverage",
+  coverageProvider: "v8",
+  coverageReporters: ["text", "json"],
+  collectCoverage: false,
+  testEnvironment: "node",
+  coverageThreshold: {
+    global: {
+      statements: "100",
+      lines: "100",
+      branches: "100",
+      functions: "100"
+    }
+  },
+  maxWorkers: 1, // this limit is being used to circumvent this issue https://github.com/facebook/jest/issues/11617
+  preset: "ts-jest",
+  roots: ["./src"]
+};

plugins/babel-fees/package.json

@@ -0,0 +1,57 @@
+{
+  "name": "@fleet-sdk/babel-fees-plugin",
+  "version": "0.1.0-alpha.14",
+  "description": "Babel Fees plugin for Fleet SDK.",
+  "main": "dist/cjs/index.js",
+  "module": "dist/esm/index.js",
+  "typings": "dist/esm/index.d.ts",
+  "sideEffects": false,
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/fleet-sdk/fleet.git",
+    "directory": "plugins/babel-fees-plugin"
+  },
+  "license": "MIT",
+  "publishConfig": {
+    "access": "public"
+  },
+  "keywords": [
+    "ergo",
+    "blockchain",
+    "babel fees"
+  ],
+  "dependencies": {
+    "@fleet-sdk/core": "workspace:^",
+    "@fleet-sdk/common": "workspace:^"
+  },
+  "scripts": {
+    "build": "run-p build:*",
+    "build:cjs": "tsc -p tsconfig.json",
+    "build:esm": "tsc -p tsconfig.esm.json",
+    "fix": "run-s fix:*",
+    "fix:prettier": "prettier src/**/*.ts --write",
+    "fix:lint": "eslint src --ext .ts --fix",
+    "test": "run-s build test:*",
+    "test:lint": "eslint src --ext .ts",
+    "test:prettier": "prettier src/**/*.ts --list-different",
+    "test:unit": "jest",
+    "watch:build": "tsc -p tsconfig.json -w",
+    "watch:test": "jest --watch",
+    "cov:html": "jest --coverage --coverageReporters=html ; open-cli coverage/index.html",
+    "cov:json": "jest --coverage --coverageReporters=json",
+    "cov:check": "jest --coverage --coverageReporters=text"
+  },
+  "engines": {
+    "node": ">=10"
+  },
+  "files": [
+    "src",
+    "dist",
+    "!**/*.spec.*",
+    "!**/*.json",
+    "!tests",
+    "CHANGELOG.md",
+    "LICENSE",
+    "README.md"
+  ]
+}

plugins/babel-fees/src/constants.ts

@@ -0,0 +1,6 @@
+export const BABEL_FEE_CONTRACT_TEMPLATE_HASH =
+  "4e83fa68ef3ed9794bbab5d8799998a9e09fb10a0afe8d1bf928936dfd11c465";
+
+export const BABEL_ERGOTREE_PREFIX = "100604000e20";
+export const BABEL_ERGOTREE_SUFFIX =
+  "0400040005000500d803d601e30004d602e4c6a70408d603e4c6a7050595e67201d804d604b2a5e4720100d605b2db63087204730000d606db6308a7d60799c1a7c17204d1968302019683050193c27204c2a7938c720501730193e4c672040408720293e4c672040505720393e4c67204060ec5a796830201929c998c7205029591b1720673028cb272067303000273047203720792720773057202";

plugins/babel-fees/src/index.ts

@@ -0,0 +1,2 @@
+export * from "./plugins";
+export * from "./utils";

plugins/babel-fees/src/plugins.spec.ts

@@ -0,0 +1,102 @@
+import { ensureBigInt, first } from "@fleet-sdk/common";
+import { SByte, SColl, SConstant, SParse, TransactionBuilder } from "@fleet-sdk/core";
+import { BabelSwapPlugin } from "./plugins";
+import { babelBoxesMock } from "./tests/babelBoxesMock";
+import { regularBoxesMock } from "./tests/regularBoxesMock";
+import { getTokenPrice, isValidBabelBox, isValidBabelContract } from "./utils";
+
+describe("Babel Swap Plugin", () => {
+  const height = 895586;
+  const changeAddress = "9hY16vzHmmfyVBwKeFGHvb2bMFsG94A1u7To1QWtUokACyFVENQ";
+
+  it("Should add babel input and output", () => {
+    const babelBox = first(babelBoxesMock);
+    const payingTokenAmount = 5n;
+
+    const tx = new TransactionBuilder(height)
+      .from(regularBoxesMock)
+      .extend(
+        BabelSwapPlugin(babelBox, {
+          tokenId: "03faf2cb329f2e90d6d23b58d91bbb6c046aa143261cc21f52fbe2824bfcbf04",
+          amount: payingTokenAmount
+        })
+      )
+      .payMinFee()
+      .sendChangeTo(changeAddress)
+      .build("EIP-12");
+
+    const input = tx.inputs.find((box) => isValidBabelBox(box));
+    if (!input || !input.extension[0]) {
+      fail();
+    }
+
+    const outputIndex = SParse<number>(input.extension[0]);
+    const output = tx.outputs[outputIndex];
+    expect(isValidBabelContract(output.ergoTree)).toBeTruthy();
+    expect(output.ergoTree).toBe(input.ergoTree);
+    expect(output.additionalRegisters.R4).toBe(input.additionalRegisters.R4);
+    expect(output.additionalRegisters.R5).toBe(input.additionalRegisters.R5);
+    expect(output.additionalRegisters.R6).toBe(SConstant(SColl(SByte, input.boxId)));
+
+    const swappedNanoErgs = getTokenPrice(input) * payingTokenAmount;
+    expect(ensureBigInt(input.value)).toBe(BigInt(output.value) + swappedNanoErgs);
+    expect(first(input.assets)).toEqual({
+      tokenId: first(output.assets).tokenId,
+      amount: (ensureBigInt(first(output.assets).amount) - payingTokenAmount).toString()
+    });
+  });
+
+  it("Should fail if invalid babel box is added", () => {
+    const nonBabelBox = regularBoxesMock[1];
+
+    expect(() => {
+      new TransactionBuilder(height)
+        .from(regularBoxesMock[0])
+        .extend(
+          BabelSwapPlugin(nonBabelBox, {
+            tokenId: "03faf2cb329f2e90d6d23b58d91bbb6c046aa143261cc21f52fbe2824bfcbf04",
+            amount: 1n
+          })
+        )
+        .payMinFee()
+        .sendChangeTo(changeAddress)
+        .build("EIP-12");
+    }).toThrow();
+  });
+
+  it("Should fail if valid babel box is added but incompatible tokenId", () => {
+    const babelBox = first(babelBoxesMock);
+
+    expect(() => {
+      new TransactionBuilder(height)
+        .from(regularBoxesMock)
+        .extend(
+          BabelSwapPlugin(babelBox, {
+            tokenId: "0cd8c9f416e5b1ca9f986a7f10a84191dfb85941619e49e53c0dc30ebf83324b",
+            amount: 10n
+          })
+        )
+        .payMinFee()
+        .sendChangeTo(changeAddress)
+        .build("EIP-12");
+    }).toThrow();
+  });
+
+  it("Should fail if the box does not have enough ERG to swap for the tokens", () => {
+    const babelBox = first(babelBoxesMock);
+
+    expect(() => {
+      new TransactionBuilder(height)
+        .from(regularBoxesMock)
+        .extend(
+          BabelSwapPlugin(babelBox, {
+            tokenId: "03faf2cb329f2e90d6d23b58d91bbb6c046aa143261cc21f52fbe2824bfcbf04",
+            amount: "10000000"
+          })
+        )
+        .payMinFee()
+        .sendChangeTo(changeAddress)
+        .build("EIP-12");
+    }).toThrow();
+  });
+});

plugins/babel-fees/src/plugins.ts

@@ -0,0 +1,55 @@
+import { ensureBigInt } from "@fleet-sdk/common";
+import {
+  Amount,
+  Box,
+  ErgoUnsignedInput,
+  FleetPlugin,
+  OutputBuilder,
+  SAFE_MIN_BOX_VALUE,
+  SByte,
+  SColl,
+  SConstant,
+  SInt,
+  TokenAmount
+} from "@fleet-sdk/core";
+import { getTokenPrice, isBabelContractForTokenId, isValidBabelBox } from "./utils";
+
+export function BabelSwapPlugin(babelBox: Box<Amount>, token: TokenAmount<Amount>): FleetPlugin {
+  return ({ addInputs, addOutputs }) => {
+    if (!isValidBabelBox(babelBox)) {
+      throw new Error("Invalid Babel Box.");
+    }
+
+    if (!isBabelContractForTokenId(babelBox.ergoTree, token.tokenId)) {
+      throw new Error(
+        `The Babel Box '${babelBox.boxId}' is not compatible with Token ID '${token.tokenId}'.`
+      );
+    }
+
+    const input = new ErgoUnsignedInput(babelBox);
+    const changeAmount = input.value - ensureBigInt(token.amount) * getTokenPrice(babelBox);
+
+    if (changeAmount < SAFE_MIN_BOX_VALUE) {
+      throw new Error(
+        "The selected Babel Box does not have enough ERG to swap for the selected amount of tokens."
+      );
+    }
+
+    const outputsLength = addOutputs(
+      new OutputBuilder(changeAmount, input.ergoTree)
+        .addTokens(input.assets)
+        .addTokens(token)
+        .setAdditionalRegisters({
+          R4: input.additionalRegisters.R4,
+          R5: input.additionalRegisters.R5,
+          R6: SConstant(SColl(SByte, input.boxId))
+        })
+    );
+
+    addInputs(
+      input.setContextVars({
+        0: SConstant(SInt(outputsLength - 1))
+      })
+    );
+  };
+}