feature: @putout/plugin-typescript: apply-type-guards: exists

Author: coderaiser

packages/plugin-typescript/lib/apply-type-guards/fixture/exists.ts

@@ -0,0 +1 @@
+const isNumber = (a): a is number => typeof a === 'number';

packages/plugin-typescript/lib/apply-type-guards/index.js

@@ -15,6 +15,10 @@ const create = template('(__a): __a is __c => typeof __a === "__b"', {
 
 module.exports.report = () => `Use 'type guards'`;
 
+module.exports.match = () => ({
+    '(__a) => typeof __a === "__b"': ({}, path) => !path.node.returnType,
+});
+
 module.exports.replace = () => ({
     '(__a) => typeof __a === "__b"': ({__a, __b}, path) => {
         replaceWith(path, create({

packages/plugin-typescript/lib/apply-type-guards/index.spec.js

@@ -18,3 +18,8 @@ test('plugin-apply-guards: transform: apply-type-guards', (t) => {
     t.transform('apply-type-guards');
     t.end();
 });
+
+test('plugin-apply-guards: no report: exists', (t) => {
+    t.noReport('exists');
+    t.end();
+});