chore: add solidity-docgen package and hardhat config

Current config auto-generates markdown in docs/ from the solidity natspec in contracts/OffsetHelper*:
npx hardhat docgen

Author: danceratopz

hardhat.config.ts

@@ -6,10 +6,12 @@ import "@nomiclabs/hardhat-waffle";
 import "@typechain/hardhat";
 import "hardhat-gas-reporter";
 import "solidity-coverage";
+import "solidity-docgen";
 import { tokens } from "./utils/tokens";
 import addresses, { mumbaiAddresses } from "./utils/addresses";
 import { network } from "hardhat";
 import { boolean } from "hardhat/internal/core/params/argumentTypes";
+import { relative } from "path";
 
 dotenv.config();
 
@@ -103,6 +105,12 @@ const config: HardhatUserConfig = {
   etherscan: {
     apiKey: process.env.POLYGONSCAN_API_KEY || "",
   },
+  docgen: {
+    pages: (item: any, file: any) =>
+      file.absolutePath.startsWith("contracts/OffsetHelper")
+        ? relative("contracts", file.absolutePath).replace(".sol", ".md")
+        : undefined,
+  },
 };
 
 export default config;

package.json

@@ -38,6 +38,7 @@
     "prettier-plugin-solidity": "^1.0.0-beta.13",
     "solhint": "^3.3.7",
     "solidity-coverage": "^0.7.20",
+    "solidity-docgen": "^0.6.0-beta.16",
     "ts-node": "^10.7.0",
     "tslib": "^2.3.1",
     "typechain": "^5.2.0",

yarn.lock

@@ -5093,7 +5093,7 @@ growl@1.10.5:
   resolved "https://registry.yarnpkg.com/growl/-/growl-1.10.5.tgz#f2735dc2283674fa67478b10181059355c369e5e"
   integrity sha512-qBr4OuELkhPenW6goKVXiv47US3clb3/IbuWF9KNKEijAy9oeHxU9IgzjvJhHkUzhaj7rOUD7+YGWqUjLp5oSA==
 
-handlebars@^4.0.1:
+handlebars@^4.0.1, handlebars@^4.7.7:
   version "4.7.7"
   resolved "https://registry.yarnpkg.com/handlebars/-/handlebars-4.7.7.tgz#9ce33416aad02dbd6c8fafa8240d5d98004945a1"
   integrity sha512-aAcXm5OAfE/8IXkcZvCepKU3VzW1/39Fb5ZuqMtgI/hT8X2YgoMvBY5dLhq/cpOvw7Lk1nK/UF71aLG/ZnVYRA==
@@ -8620,6 +8620,11 @@ solhint@^3.3.7:
   optionalDependencies:
     prettier "^1.14.3"
 
+solidity-ast@^0.4.31:
+  version "0.4.32"
+  resolved "https://registry.yarnpkg.com/solidity-ast/-/solidity-ast-0.4.32.tgz#ba613ca24c7c79007798033e8a0f32a71285f09e"
+  integrity sha512-vCx17410X+NMnpLVyg6ix4NMCHFIkvWrJb1rPBBeQYEQChX93Zgb9WB9NaIY4zpsr3Q8IvAfohw+jmuBzGf8OQ==
+
 solidity-comments-extractor@^0.0.7:
   version "0.0.7"
   resolved "https://registry.yarnpkg.com/solidity-comments-extractor/-/solidity-comments-extractor-0.0.7.tgz#99d8f1361438f84019795d928b931f4e5c39ca19"
@@ -8649,6 +8654,14 @@ solidity-coverage@^0.7.20:
     shelljs "^0.8.3"
     web3-utils "^1.3.0"
 
+solidity-docgen@^0.6.0-beta.16:
+  version "0.6.0-beta.16"
+  resolved "https://registry.yarnpkg.com/solidity-docgen/-/solidity-docgen-0.6.0-beta.16.tgz#e38613107821057ef1baa3a75b121baebb2b24db"
+  integrity sha512-FD7aUWdbtkXW41T/4K+iNXrf7ab+OmAXulDOoD0aTonz76d4wmmFLSrAfoAIo0wm9nDyYiZ1Sw1KZ89Z8sAfEQ==
+  dependencies:
+    handlebars "^4.7.7"
+    solidity-ast "^0.4.31"
+
 source-map-resolve@^0.5.0:
   version "0.5.3"
   resolved "https://registry.yarnpkg.com/source-map-resolve/-/source-map-resolve-0.5.3.tgz#190866bece7553e1f8f267a2ee82c606b5509a1a"