test(eth-json-rpc-middleware): Round out test suite (#6967)

## Explanation

Adds a number of missing unit test cases to `eth-json-rpc-middleware`,
in preparation for migrating the package to `JsonRpcEngineV2`.
Opportunistically rearranges some test utilities, e.g. renames `build*`
functions to `create*`.

## References

N/A

## Checklist

- [x] I've updated the test suite for new or updated code as appropriate
- [x] I've updated documentation (JSDoc, Markdown, etc.) for new or
updated code as appropriate
- [x] I've communicated my changes to consumers by [updating changelogs
for packages I've
changed](https://github.com/MetaMask/core/tree/main/docs/contributing.md#updating-changelogs),
highlighting breaking changes as necessary
- [x] I've prepared draft pull requests for clients and consumer
packages to resolve any breaking changes


<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Adds extensive tests across eth-json-rpc-middleware, refactors test
helpers, minor middleware typings/docs tweaks, and raises coverage
thresholds.
> 
> - **Tests (eth-json-rpc-middleware)**:
> - Add comprehensive unit tests for `block-cache`, `block-ref`,
`block-ref-rewrite`, `block-tracker-inspector`, `retryOnEmpty`, `fetch`,
`inflight-cache`, `wallet`, and package `index` exports.
> - Cover edge cases: skip-cache flags, non-cacheable methods,
pending/latest/hex block tags, empty results, transaction/receipt
caching conditions, retry exhaustion, execution-reverted errors, and
block tracker update logic.
> - **Test Utilities**:
> - Introduce `createRequest`, `createProviderAndBlockTracker`,
`createEngine`, `createFinalMiddlewareWithDefaultResult`,
`createSimpleFinalMiddleware`, and stub helpers; rename `build*` helpers
to `create*`.
>   - Remove `test/util/createHitTrackerMiddleware.ts`.
> - **Middleware/Internal**:
> - Minor refactors and JSDoc/typing improvements in
`block-ref-rewrite.ts`, `block-tracker-inspector.ts`, and
`retryOnEmpty.ts` (no functional changes intended).
> - **Config**:
> - Increase Jest coverage thresholds in `jest.config.js` and include
`./test` in `tsconfig.json`.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
24a3ce9. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

Author: rekmarks

eslint-warning-thresholds.json

@@ -153,65 +153,48 @@
   "packages/eth-block-tracker/tests/withBlockTracker.ts": {
     "@typescript-eslint/no-explicit-any": 1
   },
-  "packages/eth-json-rpc-middleware/src/block-cache.test.ts": {
-    "jsdoc/require-jsdoc": 1
-  },
   "packages/eth-json-rpc-middleware/src/block-cache.ts": {
     "@typescript-eslint/no-explicit-any": 1,
     "jsdoc/require-jsdoc": 1,
     "no-restricted-syntax": 1
   },
   "packages/eth-json-rpc-middleware/src/block-ref-rewrite.ts": {
-    "jsdoc/require-jsdoc": 1
+    "jsdoc/match-description": 1
   },
   "packages/eth-json-rpc-middleware/src/block-ref.test.ts": {
-    "@typescript-eslint/no-explicit-any": 4,
-    "jest/expect-expect": 2,
-    "jsdoc/match-description": 1
+    "jest/expect-expect": 2
   },
   "packages/eth-json-rpc-middleware/src/block-ref.ts": {
     "jsdoc/require-jsdoc": 1
   },
   "packages/eth-json-rpc-middleware/src/block-tracker-inspector.ts": {
-    "@typescript-eslint/no-explicit-any": 1,
     "jsdoc/match-description": 1,
-    "jsdoc/require-jsdoc": 2
+    "jsdoc/require-jsdoc": 1
   },
   "packages/eth-json-rpc-middleware/src/fetch.test.ts": {
     "jsdoc/match-description": 1
   },
   "packages/eth-json-rpc-middleware/src/fetch.ts": {
     "jsdoc/match-description": 1
   },
-  "packages/eth-json-rpc-middleware/src/inflight-cache.test.ts": {
-    "jsdoc/require-jsdoc": 1
-  },
   "packages/eth-json-rpc-middleware/src/inflight-cache.ts": {
     "@typescript-eslint/no-explicit-any": 1,
     "jsdoc/require-jsdoc": 4
   },
-  "packages/eth-json-rpc-middleware/src/methods/wallet-request-execution-permissions.test.ts": {
-    "jsdoc/require-jsdoc": 1
-  },
   "packages/eth-json-rpc-middleware/src/methods/wallet-request-execution-permissions.ts": {
     "jsdoc/require-jsdoc": 1
   },
-  "packages/eth-json-rpc-middleware/src/methods/wallet-revoke-execution-permission.test.ts": {
-    "jsdoc/require-jsdoc": 1
-  },
   "packages/eth-json-rpc-middleware/src/methods/wallet-revoke-execution-permission.ts": {
     "jsdoc/require-jsdoc": 1
   },
   "packages/eth-json-rpc-middleware/src/providerAsMiddleware.ts": {
     "jsdoc/require-jsdoc": 1
   },
   "packages/eth-json-rpc-middleware/src/retryOnEmpty.test.ts": {
-    "@typescript-eslint/no-explicit-any": 4,
-    "jest/expect-expect": 5,
-    "jsdoc/match-description": 4
+    "jsdoc/match-description": 3
   },
   "packages/eth-json-rpc-middleware/src/retryOnEmpty.ts": {
-    "jsdoc/require-jsdoc": 2
+    "jsdoc/match-description": 2
   },
   "packages/eth-json-rpc-middleware/src/utils/cache.ts": {
     "jsdoc/match-description": 6
@@ -222,9 +205,6 @@
   "packages/eth-json-rpc-middleware/src/utils/error.ts": {
     "jsdoc/require-jsdoc": 1
   },
-  "packages/eth-json-rpc-middleware/src/utils/normalize.test.ts": {
-    "jsdoc/require-jsdoc": 1
-  },
   "packages/eth-json-rpc-middleware/src/utils/normalize.ts": {
     "jsdoc/match-description": 3
   },
@@ -234,9 +214,6 @@
   "packages/eth-json-rpc-middleware/src/utils/validation.ts": {
     "jsdoc/require-jsdoc": 4
   },
-  "packages/eth-json-rpc-middleware/src/wallet.test.ts": {
-    "jsdoc/require-jsdoc": 1
-  },
   "packages/eth-json-rpc-middleware/src/wallet.ts": {
     "@typescript-eslint/no-explicit-any": 2,
     "@typescript-eslint/prefer-nullish-coalescing": 5,
@@ -247,12 +224,9 @@
     "@typescript-eslint/no-explicit-any": 3,
     "jsdoc/match-description": 2
   },
-  "packages/eth-json-rpc-middleware/test/util/createHitTrackerMiddleware.ts": {
-    "jsdoc/require-jsdoc": 1
-  },
   "packages/eth-json-rpc-middleware/test/util/helpers.ts": {
-    "@typescript-eslint/no-explicit-any": 1,
-    "jsdoc/match-description": 9
+    "@typescript-eslint/no-explicit-any": 5,
+    "jsdoc/match-description": 11
   },
   "packages/eth-json-rpc-provider/src/safe-event-emitter-provider.test.ts": {
     "import-x/namespace": 1

packages/eth-json-rpc-middleware/jest.config.js

@@ -20,10 +20,10 @@ module.exports = merge(baseConfig, {
   // An object that configures minimum threshold enforcement for coverage results
   coverageThreshold: {
     global: {
-      branches: 67.25,
-      functions: 81.57,
-      lines: 79.71,
-      statements: 79.83,
+      branches: 81.85,
+      functions: 90.66,
+      lines: 89.13,
+      statements: 89.2,
     },
   },
 });