TWNTY-3794 - ESLint rule: only take explicit boolean predicates in if statements (#4354)

* ESLint rule: only take explicit boolean predicates in if statements

Co-authored-by: v1b3m <vibenjamin6@gmail.com>
Co-authored-by: Toledodev <rafael.toledo@engenharia.ufjf.br>

* Merge main

Co-authored-by: v1b3m <vibenjamin6@gmail.com>
Co-authored-by: Toledodev <rafael.toledo@engenharia.ufjf.br>

* Fix frontend linter errors

Co-authored-by: v1b3m <vibenjamin6@gmail.com>
Co-authored-by: Toledodev <rafael.toledo@engenharia.ufjf.br>

* Fix jest

Co-authored-by: v1b3m <vibenjamin6@gmail.com>
Co-authored-by: Toledodev <rafael.toledo@engenharia.ufjf.br>

* Refactor according to review

Co-authored-by: v1b3m <vibenjamin6@gmail.com>
Co-authored-by: Toledodev <rafael.toledo@engenharia.ufjf.br>

* Refactor according to review

Co-authored-by: v1b3m <vibenjamin6@gmail.com>
Co-authored-by: Toledodev <rafael.toledo@engenharia.ufjf.br>

* Fix lint on new code

Co-authored-by: v1b3m <vibenjamin6@gmail.com>
Co-authored-by: Toledodev <rafael.toledo@engenharia.ufjf.br>

---------

Co-authored-by: gitstart-twenty <gitstart-twenty@users.noreply.github.com>
Co-authored-by: v1b3m <vibenjamin6@gmail.com>
Co-authored-by: Toledodev <rafael.toledo@engenharia.ufjf.br>

tools/eslint-rules/index.ts

@@ -6,6 +6,10 @@ import {
   rule as effectComponents,
   RULE_NAME as effectComponentsName,
 } from './rules/effect-components';
+import {
+  rule as explicitBooleanPredicatesInIf,
+  RULE_NAME as explicitBooleanPredicatesInIfName,
+} from './rules/explicit-boolean-predicates-in-if';
 import {
   rule as matchingStateVariable,
   RULE_NAME as matchingStateVariableName,
@@ -69,6 +73,7 @@ module.exports = {
     [sortCssPropertiesAlphabeticallyName]: sortCssPropertiesAlphabetically,
     [styledComponentsPrefixedWithStyledName]:
       styledComponentsPrefixedWithStyled,
+    [explicitBooleanPredicatesInIfName]: explicitBooleanPredicatesInIf,
     [useGetLoadableAndGetValueToGetAtomsName]:
       useGetLoadableAndGetValueToGetAtoms,
     [maxConstsPerFileName]: maxConstsPerFile,

tools/eslint-rules/rules/explicit-boolean-predicates-in-if.ts

@@ -0,0 +1,43 @@
+import { ESLintUtils, TSESTree } from '@typescript-eslint/experimental-utils';
+
+export const RULE_NAME = 'explicit-boolean-predicates-in-if';
+
+export const rule = ESLintUtils.RuleCreator(() => __filename)({
+  name: RULE_NAME,
+  meta: {
+    type: 'suggestion',
+    docs: {
+      description: 'Enforce explicit boolean predicates in if statements',
+      recommended: 'warn',
+    },
+    fixable: 'code',
+    schema: [],
+    messages: {
+      nonExplicitPredicate:
+        'Use an explicit boolean predicate in if statements.',
+    },
+  },
+  defaultOptions: [],
+  create: (context) => {
+    const parserServices = ESLintUtils.getParserServices(context);
+    const typeChecker = parserServices.program.getTypeChecker();
+
+    return {
+      IfStatement: (node: TSESTree.IfStatement) => {
+        const tsNode = parserServices.esTreeNodeToTSNodeMap.get(node.test);
+        const type = typeChecker.getTypeAtLocation(tsNode);
+
+        if (typeChecker.typeToString(type) !== 'boolean') {
+          const { test } = node;
+
+          context.report({
+            node: test,
+            messageId: 'nonExplicitPredicate',
+          });
+        }
+      },
+    };
+  },
+});
+
+export default rule;

tools/eslint-rules/rules/use-getLoadable-and-getValue-to-get-atoms.spec.ts

@@ -25,20 +25,19 @@ ruleTester.run(RULE_NAME, rule, {
       code: 'const atoms = await snapshot.getPromise(someState);',
       errors: [
         {
-          messageId: 'invalidWayToGetAtoms',
+          messageId: 'invalidAccessorOnSnapshot',
         },
       ],
-      output: 'const atoms = snapshot.getLoadable(someState).getValue();',
+      output: 'const atoms = await snapshot.getLoadable(someState);',
     },
     {
       code: 'const atoms = await snapshot.getPromise(someState(viewId));',
       errors: [
         {
-          messageId: 'invalidWayToGetAtoms',
+          messageId: 'invalidAccessorOnSnapshot',
         },
       ],
-      output:
-        'const atoms = snapshot.getLoadable(someState(viewId)).getValue();',
+      output: 'const atoms = await snapshot.getLoadable(someState(viewId));',
     },
     {
       code: 'const atoms = snapshot.getLoadable(someState).anotherMethod();',