contracts: add inspect hh task (#3301)

This hardhat task mirrors functionality of `forge inspect`
where you can pass a contract name and a compiler output field
and it will print that field for you. This will be useful for
building sets of `storageLayout`s and `methodIdentifiers` to
compare against the bedrock contracts.

Example usage:

```
$ npx hardhat inspect AddressDictator storageLayout
```

Where `AddressDictator` can be any contract in the package
and `storageLayout` can be one of the following:

- abi
- bytecode
- deployedBytecode
- storageLayout
- methodIdentifiers

This is one of the more useful features of foundry so porting it
to hardhat will make storageLayout inspections much easier.
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

.changeset/fifty-books-remain.md

+---
+'@eth-optimism/contracts': patch
+---
+
+Add inspect hh task

packages/contracts/tasks/index.ts

@@ -6,3 +6,4 @@ export * from './whitelist'
 export * from './withdraw-fees'
 export * from './fetch-batches'
 export * from './deploy-teleportr'
+export * from './inspect'

packages/contracts/tasks/inspect.ts

+import { task } from 'hardhat/config'
+import * as types from 'hardhat/internal/core/params/argumentTypes'
+
+const getFullyQualifiedName = (
+  sourceName: string,
+  contractName: string
+): string => {
+  return `${sourceName}:${contractName}`
+}
+
+task('inspect')
+  .addPositionalParam(
+    'contractName',
+    'Name of the contract to inspect',
+    undefined,
+    types.string,
+    false
+  )
+  .addPositionalParam(
+    'field',
+    'Compiler output field to inspect',
+    undefined,
+    types.string,
+    false
+  )
+  .setAction(async (args, hre) => {
+    const artifact = await hre.artifacts.readArtifact(args.contractName)
+    const fqn = getFullyQualifiedName(
+      artifact.sourceName,
+      artifact.contractName
+    )
+    const buildInfo = await hre.artifacts.getBuildInfo(fqn)
+    const info =
+      buildInfo.output.contracts[artifact.sourceName][artifact.contractName]
+    if (!info) {
+      throw new Error(`Cannot find build info for ${fqn}`)
+    }
+
+    try {
+      switch (args.field) {
+        case 'abi': {
+          const abi = info.abi
+          console.log(JSON.stringify(abi, null, 2))
+          break
+        }
+        case 'bytecode': {
+          const bytecode = info.evm.bytecode.object
+          console.log('0x' + bytecode)
+          break
+        }
+        case 'deployedBytecode': {
+          const bytecode = info.evm.deployedBytecode.object
+          console.log('0x' + bytecode)
+          break
+        }
+        case 'storageLayout': {
+          const storageLayout = (info as any).storageLayout
+          console.log(JSON.stringify(storageLayout, null, 2))
+          break
+        }
+        case 'methodIdentifiers': {
+          const methodIdentifiers = info.evm.methodIdentifiers
+          console.log(JSON.stringify(methodIdentifiers, null, 2))
+          break
+        }
+        default: {
+          console.log(
+            JSON.stringify(
+              {
+                error: `Unsupported field ${args.field}`,
+              },
+              null,
+              2
+            )
+          )
+          break
+        }
+      }
+    } catch (e) {
+      console.log(
+        JSON.stringify(
+          {
+            error: `Cannot find ${args.field}, be sure to enable it in compiler settings`,
+          },
+          null,
+          2
+        )
+      )
+    }
+  })