From 9c033a481d41252d88f05668723f7e061d37f562 Mon Sep 17 00:00:00 2001
From: Lauren Tan <poteto@users.noreply.github.com>
Date: Thu, 22 Jun 2023 10:18:43 -0400
Subject: [PATCH] [eslint-plugin] Only report on InvalidInput errors

Invariants aren't actionable by users, so we can omit reporting them in eslint
as errors (while continuing to throw in the compiler itself)
---
 .../babel-plugin-react-forget/src/index.ts    |  2 +-
 .../__tests__/ReactForgetDiagnostics-test.ts  | 41 ++++++++-----------
 .../eslint-plugin-react-forget/package.json   |  1 +
 .../src/rules/ReactForgetDiagnostics.ts       | 31 +++++++++++++-
 4 files changed, 47 insertions(+), 28 deletions(-)

diff --git a/compiler/forget/packages/babel-plugin-react-forget/src/index.ts b/compiler/forget/packages/babel-plugin-react-forget/src/index.ts
index 5b644863d1..669f53022f 100644
--- a/compiler/forget/packages/babel-plugin-react-forget/src/index.ts
+++ b/compiler/forget/packages/babel-plugin-react-forget/src/index.ts
@@ -19,7 +19,7 @@ export {
   parsePluginOptions,
   run,
 } from "./Entrypoint";
-export { Effect, Hook, ValueKind, printHIR } from "./HIR";
+export { Effect, Hook, SourceLocation, ValueKind, printHIR } from "./HIR";
 export { printReactiveFunction } from "./ReactiveScopes";
 
 declare global {
diff --git a/compiler/forget/packages/eslint-plugin-react-forget/__tests__/ReactForgetDiagnostics-test.ts b/compiler/forget/packages/eslint-plugin-react-forget/__tests__/ReactForgetDiagnostics-test.ts
index a2e0fb8dac..249325e4b6 100644
--- a/compiler/forget/packages/eslint-plugin-react-forget/__tests__/ReactForgetDiagnostics-test.ts
+++ b/compiler/forget/packages/eslint-plugin-react-forget/__tests__/ReactForgetDiagnostics-test.ts
@@ -41,6 +41,22 @@ const tests: ForgetTestCases = {
         }
       `,
     },
+    {
+      // OK because invariants are only meant for the compiler team's consumption
+      name: "[Invariant] Defined after use",
+      code: normalizeIndent`
+        function Component(props) {
+          'use forget';
+          let y = function () {
+            m(x);
+          };
+
+          let x = { a };
+          m(x);
+          return y;
+        }
+      `,
+    },
   ],
   invalid: [
     {
@@ -64,31 +80,6 @@ const tests: ForgetTestCases = {
         },
       ],
     },
-    {
-      name: "[Invariant] Defined after use",
-      code: normalizeIndent`
-        function Component(props) {
-          'use forget';
-          let y = function () {
-            m(x);
-          };
-
-          let x = { a };
-          m(x);
-          return y;
-        }
-      `,
-      errors: [
-        {
-          message:
-            "[ReactForget] Invariant: EnterSSA: Expected identifier to be defined before being used. Identifier x$1 is undefined (8:8)",
-          line: 8,
-          column: 3,
-          endColumn: 17,
-          endLine: 8,
-        },
-      ],
-    },
   ],
 };
 
diff --git a/compiler/forget/packages/eslint-plugin-react-forget/package.json b/compiler/forget/packages/eslint-plugin-react-forget/package.json
index fdad2e8ebb..b7a7b61931 100644
--- a/compiler/forget/packages/eslint-plugin-react-forget/package.json
+++ b/compiler/forget/packages/eslint-plugin-react-forget/package.json
@@ -30,6 +30,7 @@
     "@babel/eslint-parser": "^7.19.1",
     "@babel/preset-env": "^7.22.4",
     "@babel/preset-typescript": "^7.18.6",
+    "@babel/types": "^7.19.0",
     "@types/node": "^20.2.5",
     "babel-jest": "^29.0.3",
     "eslint": "^8.19.0",
diff --git a/compiler/forget/packages/eslint-plugin-react-forget/src/rules/ReactForgetDiagnostics.ts b/compiler/forget/packages/eslint-plugin-react-forget/src/rules/ReactForgetDiagnostics.ts
index e9a770551c..68355d2eac 100644
--- a/compiler/forget/packages/eslint-plugin-react-forget/src/rules/ReactForgetDiagnostics.ts
+++ b/compiler/forget/packages/eslint-plugin-react-forget/src/rules/ReactForgetDiagnostics.ts
@@ -6,17 +6,44 @@
  */
 
 import { transformFromAstSync } from "@babel/core";
+import type { SourceLocation as BabelSourceLocation } from "@babel/types";
 import ReactForgetBabelPlugin, {
-  CompilerError,
+  ErrorSeverity,
+  type CompilerError,
+  type CompilerErrorDetail,
   type PluginOptions,
 } from "babel-plugin-react-forget";
 import type { Rule } from "eslint";
 import * as HermesParser from "hermes-parser";
 
+type CompilerErrorDetailWithLoc = Omit<CompilerErrorDetail, "loc"> & {
+  loc: BabelSourceLocation;
+};
+
 function isReactForgetCompilerError(err: Error): err is CompilerError {
   return err.name === "ReactForgetCompilerError";
 }
 
+function isReportableDiagnostic(
+  detail: CompilerErrorDetail
+): detail is CompilerErrorDetailWithLoc {
+  let isCorrectSeverity = false;
+  switch (detail.severity) {
+    case ErrorSeverity.InvalidInput:
+      isCorrectSeverity = true;
+      break;
+    case ErrorSeverity.Invariant:
+    case ErrorSeverity.Todo:
+      break;
+  }
+
+  return (
+    isCorrectSeverity === true &&
+    detail.loc != null &&
+    typeof detail.loc !== "symbol"
+  );
+}
+
 const rule: Rule.RuleModule = {
   meta: {
     type: "problem",
@@ -61,7 +88,7 @@ const rule: Rule.RuleModule = {
       } catch (err) {
         if (isReactForgetCompilerError(err) && Array.isArray(err.details)) {
           for (const detail of err.details) {
-            if (detail.loc != null && typeof detail.loc !== "symbol") {
+            if (isReportableDiagnostic(detail)) {
               context.report({
                 message: detail.toString(),
                 loc: detail.loc,