feature: @putout/engine-runner: improve plugins validation (#218)

packages/engine-runner/lib/include.js

@@ -2,11 +2,10 @@
 
 const log = require('debug')('putout:runner:include');
 const maybeArray = require('./maybe-array');
+const {validate} = require('./validate');
 
-const {stringify} = JSON;
 const stub = () => [];
 const good = () => true;
-const isFn = (a) => typeof a === 'function';
 
 module.exports = ({rule, plugin, msg, options}) => {
     const {
@@ -64,8 +63,3 @@ const getTraverse = (include, filter, rule) => ({push, options}) => {
 
     return result;
 };
-
-function validate(name, fn) {
-    if (!isFn(fn))
-        throw Error(`☝️ Looks like '${name}' is not a 'function' but '${typeof fn}' with value: '${stringify(fn)}'. More on using Includer: https://git.io/JqcMn`);
-}

packages/engine-runner/lib/merge-visitors.js

@@ -6,6 +6,7 @@ const {generate} = require('@putout/engine-parser');
 const runFix = require('./run-fix');
 const {getPosition} = require('./get-position');
 const maybeArray = require('./maybe-array');
+const {validate} = require('./validate');
 
 const {
     listStore,
@@ -23,8 +24,10 @@ const {assign} = Object;
 const parse = (name, plugin, options) => {
     const list = [];
 
-    if (plugin[name])
+    if (plugin[name]) {
+        validate(name, plugin[name]);
         list.push(...maybeArray(plugin[name]()));
+    }
 
     if (options[name])
         list.push(...maybeArray(options[name]));

packages/engine-runner/lib/validate.js

@@ -0,0 +1,9 @@
+'use strict';
+
+const isFn = (a) => typeof a === 'function';
+const {stringify} = JSON;
+
+module.exports.validate = (name, fn) => {
+    if (!isFn(fn))
+        throw Error(`☝️ Looks like '${name}' is not a 'function' but '${typeof fn}' with value: '${stringify(fn)}'. More on using Includer: https://git.io/JqcMn`);
+};

packages/engine-runner/test/include.js

@@ -116,3 +116,41 @@ test('putout: runner: include: no fix', (t) => {
     t.equal(error.message, expected);
     t.end();
 });
+
+test('putout: runner: include: not function, with traverse', (t) => {
+    const source = `import type { Query } from 'assets/core_api/types/query'`;
+    const unyield = {
+        report: () => `Use 'return' instead of 'yield'`,
+        include: ['YieldExpression'],
+        fix: (path) => {
+            path.replaceWith(path.node.argument); // I want to just have the argument, not return it, I had this wrong earlier
+        },
+        traverse: ({push}) => ({
+            YieldExpression(path) {
+                push(path);
+            },
+            Program: {
+                exit(path) {
+                    path.traverse({
+                        Function(path) {
+                            push(path);
+                        },
+                    });
+                },
+            },
+        }),
+    };
+
+    const [error] = tryCatch(putout, source, {
+        isTS: true,
+        fix: true,
+        plugins: [{
+            unyield,
+        }],
+    });
+
+    const expected = `☝️ Looks like 'include' is not a 'function' but 'object' with value: '["YieldExpression"]'. More on using Includer: https://git.io/JqcMn`;
+
+    t.equal(error.message, expected);
+    t.end();
+});