typescript-eslint · JoshuaKGoldberg · Jun 8, 2024 · Jun 3, 2024 · Jun 3, 2024 · Jun 3, 2024
diff --git a/packages/eslint-plugin/docs/rules/no-floating-promises.mdx b/packages/eslint-plugin/docs/rules/no-floating-promises.mdx
@@ -176,6 +176,44 @@ returnsSafePromise();
 </TabItem>
 </Tabs>
 
+### `allowForKnownSafeCalls`
+
+This option allows marking specific functions as "safe" to be called to create floating Promises.
+For example, you may need to do this in the case of libraries whose APIs may be called without handling the resultant Promises.
+
+This option takes the same array format as [`allowForKnownSafePromises`](#allowForKnownSafePromises).
+
+Examples of code for this rule with:
+
+```json
+{
+  "allowForKnownSafeCalls": [
+    { "from": "file", "name": "safe", "path": "input.ts" }
+  ]
+}
+```
+
+<Tabs>
+<TabItem value="❌ Incorrect">
+
+```ts option='{"allowForKnownSafeCalls":[{"from":"file","name":"safe","path":"input.ts"}]}'
+declare function unsafe(...args: unknown[]): Promise<void>;
+
+unsafe('...', () => {});
+```
+
+</TabItem>
+<TabItem value="✅ Correct">
+
+```ts option='{"allowForKnownSafeCalls":[{"from":"file","name":"safe","path":"input.ts"}]}' skipValidation
+declare function safe(...args: unknown[]): Promise<void>;
+
+safe('...', () => {});
+```
+
+</TabItem>
+</Tabs>
+
 ## When Not To Use It
 
 This rule can be difficult to enable on large existing projects that set up many floating Promises.

diff --git a/packages/eslint-plugin/src/rules/no-floating-promises.ts b/packages/eslint-plugin/src/rules/no-floating-promises.ts
@@ -19,6 +19,7 @@ type Options = [
     ignoreVoid?: boolean;
     ignoreIIFE?: boolean;
     allowForKnownSafePromises?: TypeOrValueSpecifier[];
+    allowForKnownSafeCalls?: TypeOrValueSpecifier[];
   },
 ];
 
@@ -85,6 +86,7 @@ export default createRule<Options, MessageId>({
             type: 'boolean',
           },
           allowForKnownSafePromises: readonlynessOptionsSchema.properties.allow,
+          allowForKnownSafeCalls: readonlynessOptionsSchema.properties.allow,
         },
         additionalProperties: false,
       },
@@ -96,15 +98,18 @@ export default createRule<Options, MessageId>({
       ignoreVoid: true,
       ignoreIIFE: false,
       allowForKnownSafePromises: readonlynessOptionsDefaults.allow,
+      allowForKnownSafeCalls: readonlynessOptionsDefaults.allow,
     },
   ],
 
   create(context, [options]) {
     const services = getParserServices(context);
     const checker = services.program.getTypeChecker();
     // TODO: #5439
-    // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+    /* eslint-disable @typescript-eslint/no-non-null-assertion */
     const allowForKnownSafePromises = options.allowForKnownSafePromises!;
+    const allowForKnownSafeCalls = options.allowForKnownSafeCalls!;
+    /* eslint-enable @typescript-eslint/no-non-null-assertion */
 
     return {
       ExpressionStatement(node): void {
@@ -118,6 +123,10 @@ export default createRule<Options, MessageId>({
           expression = expression.expression;
         }
 
+        if (isKnownSafePromiseReturn(expression)) {
+          return;
+        }
+
         const { isUnhandled, nonFunctionHandler, promiseArray } =
           isUnhandledPromise(checker, expression);
 
@@ -197,6 +206,18 @@ export default createRule<Options, MessageId>({
       },
     };
 
+    function isKnownSafePromiseReturn(node: TSESTree.Node): boolean {
+      if (node.type !== AST_NODE_TYPES.CallExpression) {
+        return false;
+      }
+
+      const type = services.getTypeAtLocation(node.callee);
+
+      return allowForKnownSafeCalls.some(allowedType =>
+        typeMatchesSpecifier(type, allowedType, services.program),
+      );
+    }
+
     function isHigherPrecedenceThanUnary(node: ts.Node): boolean {
       const operator = ts.isBinaryExpression(node)
         ? node.operatorToken.kind

diff --git a/packages/eslint-plugin/tests/docs-eslint-output-snapshots/no-floating-promises.shot b/packages/eslint-plugin/tests/docs-eslint-output-snapshots/no-floating-promises.shot
diff --git a/packages/eslint-plugin/tests/rules/no-floating-promises.test.ts b/packages/eslint-plugin/tests/rules/no-floating-promises.test.ts
@@ -698,6 +698,27 @@ myTag\`abc\`;
         { allowForKnownSafePromises: [{ from: 'file', name: 'SafePromise' }] },
       ],
     },
+    {
+      code: `
+        declare function it(...args: unknown[]): Promise<void>;
+
+        it('...', () => {});
+      `,
+      options: [
+        {
+          allowForKnownSafeCalls: [
+            {
+              from: 'file',
+              name: 'it',
+              // https://github.com/typescript-eslint/typescript-eslint/pull/9234/files#r1626465054
+              path: process.env.TYPESCRIPT_ESLINT_PROJECT_SERVICE
+                ? 'file.ts'
+                : 'tests/fixtures/file.ts',
+            },
+          ],
+        },
+      ],
+    },
     {
       code: `
 declare const myTag: (strings: TemplateStringsArray) => Promise<void>;
@@ -2181,5 +2202,71 @@ myTag\`abc\`;
       options: [{ allowForKnownSafePromises: [{ from: 'file', name: 'Foo' }] }],
       errors: [{ line: 4, messageId: 'floatingVoid' }],
     },
+    {
+      code: `
+        declare function unsafe(...args: unknown[]): Promise<void>;
+
+        unsafe('...', () => {});
+      `,
+      errors: [{ line: 4, messageId: 'floatingVoid' }],
+      options: [
+        {
+          allowForKnownSafeCalls: [
+            {
+              from: 'file',
+              name: 'it',
+              // https://github.com/typescript-eslint/typescript-eslint/pull/9234/files#r1626465054
+              path: process.env.TYPESCRIPT_ESLINT_PROJECT_SERVICE
+                ? 'file.ts'
+                : 'tests/fixtures/file.ts',
+            },
+          ],
+        },
+      ],
+    },
+    {
+      code: `
+        declare function it(...args: unknown[]): Promise<void>;
+
+        it('...', () => {}).then(() => {});
+      `,
+      errors: [{ line: 4, messageId: 'floatingVoid' }],
+      options: [
+        {
+          allowForKnownSafeCalls: [
+            {
+              from: 'file',
+              name: 'it',
+              // https://github.com/typescript-eslint/typescript-eslint/pull/9234/files#r1626465054
+              path: process.env.TYPESCRIPT_ESLINT_PROJECT_SERVICE
+                ? 'file.ts'
+                : 'tests/fixtures/file.ts',
+            },
+          ],
+        },
+      ],
+    },
+    {
+      code: `
+        declare function it(...args: unknown[]): Promise<void>;
+
+        it('...', () => {}).finally(() => {});
+      `,
+      errors: [{ line: 4, messageId: 'floatingVoid' }],
+      options: [
+        {
+          allowForKnownSafeCalls: [
+            {
+              from: 'file',
+              name: 'it',
+              // https://github.com/typescript-eslint/typescript-eslint/pull/9234/files#r1626465054
+              path: process.env.TYPESCRIPT_ESLINT_PROJECT_SERVICE
+                ? 'file.ts'
+                : 'tests/fixtures/file.ts',
+            },
+          ],
+        },
+      ],
+    },
   ],
 });
diff --git a/packages/eslint-plugin/tests/schema-snapshots/no-floating-promises.shot b/packages/eslint-plugin/tests/schema-snapshots/no-floating-promises.shot