feat(no-import-operators): add suggestion

We're only adding a suggestion right now because an auto-fixer might break if the operator is old and not exported from `rxjs` too.

Author: JasonWeinzierl

README.md

@@ -88,7 +88,7 @@ The package includes the following rules.
 | [no-ignored-subscription](docs/rules/no-ignored-subscription.md)       | Disallow ignoring the subscription returned by `subscribe`.                                               |    |    |    | 💭 |    |
 | [no-ignored-takewhile-value](docs/rules/no-ignored-takewhile-value.md) | Disallow ignoring the value within `takeWhile`.                                                           | ✅  |    |    |    |    |
 | [no-implicit-any-catch](docs/rules/no-implicit-any-catch.md)           | Disallow implicit `any` error parameters in `catchError` operators.                                       | ✅  | 🔧 | 💡 | 💭 |    |
-| [no-import-operators](docs/rules/no-import-operators.md)               | Disallow importing operators from `rxjs/operators`.                                                       |    |    |    |    |    |
+| [no-import-operators](docs/rules/no-import-operators.md)               | Disallow importing operators from `rxjs/operators`.                                                       |    |    | 💡 |    |    |
 | [no-index](docs/rules/no-index.md)                                     | Disallow importing index modules.                                                                         | ✅  |    |    |    |    |
 | [no-internal](docs/rules/no-internal.md)                               | Disallow importing internal modules.                                                                      | ✅  | 🔧 | 💡 |    |    |
 | [no-nested-subscribe](docs/rules/no-nested-subscribe.md)               | Disallow calling `subscribe` within a `subscribe` callback.                                               | ✅  |    |    | 💭 |    |

docs/rules/no-import-operators.md

@@ -1,5 +1,7 @@
 # Disallow importing operators from `rxjs/operators` (`rxjs-x/no-import-operators`)
 
+💡 This rule is manually fixable by [editor suggestions](https://eslint.org/docs/latest/use/core-concepts#rule-suggestions).
+
 <!-- end auto-generated rule header -->
 
 This rule prevents importing from the `rxjs/operators` export site.

src/rules/no-import-operators.ts

@@ -7,38 +7,56 @@ export const noImportOperatorsRule = ruleCreator({
     docs: {
       description: 'Disallow importing operators from `rxjs/operators`.',
     },
+    hasSuggestions: true,
     messages: {
       forbidden: 'RxJS imports from `rxjs/operators` are forbidden.',
+      suggest: 'Import from `rxjs` instead.',
     },
     schema: [],
     type: 'problem',
   },
   name: 'no-import-operators',
   create: (context) => {
-    return {
-      'ImportDeclaration Literal[value="rxjs/operators"]': (node: es.Literal) => {
+    function getReplacement(rawLocation: string) {
+      const match = /^\s*('|")/.exec(rawLocation);
+      if (!match) {
+        return undefined;
+      }
+      const [, quote] = match;
+      if (/^['"]rxjs\/operators/.test(rawLocation)) {
+        return `${quote}rxjs${quote}`;
+      }
+      return undefined;
+    }
+
+    function reportNode(node: es.Literal) {
+      const replacement = getReplacement(node.raw);
+      if (replacement) {
         context.report({
           messageId: 'forbidden',
           node,
+          suggest: [{ messageId: 'suggest', fix: (fixer) => fixer.replaceText(node, replacement) }],
         });
-      },
-      'ImportExpression Literal[value="rxjs/operators"]': (node: es.Literal) => {
+      } else {
         context.report({
           messageId: 'forbidden',
           node,
         });
+      }
+    }
+
+    return {
+      'ImportDeclaration Literal[value="rxjs/operators"]': (node: es.Literal) => {
+        reportNode(node);
+      },
+      'ImportExpression Literal[value="rxjs/operators"]': (node: es.Literal) => {
+        reportNode(node);
       },
       'ExportNamedDeclaration Literal[value="rxjs/operators"]': (node: es.Literal) => {
-        context.report({
-          messageId: 'forbidden',
-          node,
-        });
+        reportNode(node);
       },
       'ExportAllDeclaration Literal[value="rxjs/operators"]': (node: es.Literal) => {
-        context.report({
-          messageId: 'forbidden',
-          node,
-        });
+        reportNode(node);
       },
     };
   },

tests/rules/no-import-operators.test.ts

@@ -45,38 +45,102 @@ ruleTester({ types: false }).run('no-import-operators', noImportOperatorsRule, {
       stripIndent`
         // import declaration named
         import { concat } from "rxjs/operators";
-                               ~~~~~~~~~~~~~~~~ [forbidden]
+                               ~~~~~~~~~~~~~~~~ [forbidden suggest 0]
         import { concat } from 'rxjs/operators';
-                               ~~~~~~~~~~~~~~~~ [forbidden]
+                               ~~~~~~~~~~~~~~~~ [forbidden suggest 1]
       `,
+      {
+        suggestions: [
+          {
+            messageId: 'suggest',
+            output: stripIndent`
+              // import declaration named
+              import { concat } from "rxjs";
+              import { concat } from 'rxjs/operators';
+            `,
+          },
+          {
+            messageId: 'suggest',
+            output: stripIndent`
+              // import declaration named
+              import { concat } from "rxjs/operators";
+              import { concat } from 'rxjs';
+            `,
+          },
+        ],
+      },
     ),
     fromFixture(
       stripIndent`
         // import declaration namespace
         import * as RxOperators from "rxjs/operators";
-                                     ~~~~~~~~~~~~~~~~ [forbidden]
+                                     ~~~~~~~~~~~~~~~~ [forbidden suggest]
       `,
+      {
+        suggestions: [
+          {
+            messageId: 'suggest',
+            output: stripIndent`
+              // import declaration namespace
+              import * as RxOperators from "rxjs";
+            `,
+          },
+        ],
+      },
     ),
     fromFixture(
       stripIndent`
         // import expression
         const { concat } = await import("rxjs/operators");
-                                        ~~~~~~~~~~~~~~~~ [forbidden]
+                                        ~~~~~~~~~~~~~~~~ [forbidden suggest]
       `,
+      {
+        suggestions: [
+          {
+            messageId: 'suggest',
+            output: stripIndent`
+            // import expression
+            const { concat } = await import("rxjs");
+          `,
+          },
+        ],
+      },
     ),
     fromFixture(
       stripIndent`
         // export named
         export { concat } from "rxjs/operators";
-                               ~~~~~~~~~~~~~~~~ [forbidden]
+                               ~~~~~~~~~~~~~~~~ [forbidden suggest]
       `,
+      {
+        suggestions: [
+          {
+            messageId: 'suggest',
+            output: stripIndent`
+              // export named
+              export { concat } from "rxjs";
+            `,
+          },
+        ],
+      },
     ),
     fromFixture(
       stripIndent`
         // export all
         export * from "rxjs/operators";
-                      ~~~~~~~~~~~~~~~~ [forbidden]
+                      ~~~~~~~~~~~~~~~~ [forbidden suggest]
       `,
+      {
+        suggestions: [
+          {
+            messageId: 'suggest',
+            output: stripIndent`
+              // export all
+              export * from "rxjs";
+            `,
+          },
+        ],
+      },
     ),
   ],
 });