Startup Performance Optimization

.eslintrc.json

@@ -17,7 +17,7 @@
 
     "overrides": [
         {
-            "files": [ "test/**/*.js" ],
+            "files": [ "test/**/*.js", "benchmarks/**/*.js" ],
             "env": { "mocha": true },
             "rules": {
                 "max-nested-callbacks": [ "error", 8 ]

benchmarks/startup.bench.js

@@ -0,0 +1,20 @@
+'use strict';
+
+const os = require('os');
+const { expect } = require('chai');
+const { performance } = require('perf_hooks');
+
+const [ { speed: cpuSpeed } ] = os.cpus();
+
+describe('startup / require time', () => {
+    it('should not take longer as the defined budget to require the plugin', () => {
+        const budget = 75000 / cpuSpeed;
+
+        const startTime = performance.now();
+        require('../index');
+        const endTime = performance.now();
+        const loadTime = endTime - startTime;
+
+        expect(loadTime).to.be.below(budget);
+    });
+});

lib/rules/handle-done-callback.js

@@ -1,6 +1,6 @@
 'use strict';
 
-const R = require('ramda');
+const find = require('ramda/src/find');
 const astUtils = require('../util/ast');
 
 module.exports = function (context) {
@@ -9,7 +9,7 @@ module.exports = function (context) {
     }
 
     function findParamInScope(paramName, scope) {
-        return R.find(function (variable) {
+        return find(function (variable) {
             return variable.name === paramName && variable.defs[0].type === 'Parameter';
         }, scope.variables);
     }

lib/rules/max-top-level-suites.js

@@ -5,7 +5,7 @@
  * @author Alexander Afanasyev
  */
 
-const R = require('ramda');
+const isNil = require('ramda/src/isNil');
 const astUtil = require('../util/ast');
 const { additionalSuiteNames } = require('../util/settings');
 
@@ -18,7 +18,7 @@ module.exports = function (context) {
     const settings = context.settings;
     let suiteLimit;
 
-    if (R.isNil(options.limit)) {
+    if (isNil(options.limit)) {
         suiteLimit = defaultSuiteLimit;
     } else {
         suiteLimit = options.limit;

lib/rules/no-mocha-arrows.js

@@ -5,7 +5,7 @@
  * @author Paul Melnikow
  */
 
-const R = require('ramda');
+const last = require('ramda/src/last');
 const astUtils = require('../util/ast');
 
 module.exports = function (context) {
@@ -25,7 +25,7 @@ module.exports = function (context) {
         }
 
         if (fn.params.length > 0) {
-            paramsFullText = `(${ sourceCode.text.slice(fn.params[0].start, R.last(fn.params).end) })`;
+            paramsFullText = `(${ sourceCode.text.slice(fn.params[0].start, last(fn.params).end) })`;
         }
 
         return `${functionKeyword}${paramsFullText} `;

lib/rules/no-synchronous-tests.js

@@ -1,6 +1,7 @@
 'use strict';
 
-const R = require('ramda');
+const isNil = require('ramda/src/isNil');
+const find = require('ramda/src/find');
 const astUtil = require('../util/ast');
 
 const asyncMethods = [ 'async', 'callback', 'promise' ];
@@ -14,7 +15,7 @@ function isAsyncFunction(functionExpression) {
 }
 
 function findPromiseReturnStatement(nodes) {
-    return R.find(function (node) {
+    return find(function (node) {
         return node.type === 'ReturnStatement' && node.argument && node.argument.type !== 'Literal';
     }, nodes);
 }
@@ -36,7 +37,7 @@ function doesReturnPromise(functionExpression) {
 
 module.exports = function (context) {
     const options = context.options[0] || {};
-    const allowedAsyncMethods = R.isNil(options.allowed) ? asyncMethods : options.allowed;
+    const allowedAsyncMethods = isNil(options.allowed) ? asyncMethods : options.allowed;
 
     function check(node) {
         if (astUtil.hasParentMochaFunctionCall(node)) {

lib/util/ast.js

@@ -1,9 +1,14 @@
 'use strict';
 
-const R = require('ramda');
+const complement = require('ramda/src/complement');
+const both = require('ramda/src/both');
+const isNil = require('ramda/src/isNil');
+const propEq = require('ramda/src/propEq');
+const pathEq = require('ramda/src/pathEq');
+const find = require('ramda/src/find');
 
-const isDefined = R.complement(R.isNil);
-const isCallExpression = R.both(isDefined, R.propEq('type', 'CallExpression'));
+const isDefined = complement(isNil);
+const isCallExpression = both(isDefined, propEq('type', 'CallExpression'));
 
 const describeAliases = [
     'describe', 'xdescribe', 'describe.only', 'describe.skip',
@@ -59,9 +64,9 @@ function isTestCase(node) {
 }
 
 function findReference(scope, node) {
-    const hasSameRangeAsNode = R.pathEq([ 'identifier', 'range' ], node.range);
+    const hasSameRangeAsNode = pathEq([ 'identifier', 'range' ], node.range);
 
-    return R.find(hasSameRangeAsNode, scope.references);
+    return find(hasSameRangeAsNode, scope.references);
 }
 
 function isShadowed(scope, identifier) {
@@ -103,7 +108,7 @@ function isReturnOfUndefined(node) {
     return isImplicitUndefined || isExplicitUndefined(argument);
 }
 
-const findReturnStatement = R.find(R.propEq('type', 'ReturnStatement'));
+const findReturnStatement = find(propEq('type', 'ReturnStatement'));
 
 module.exports = {
     isDescribe,

package.json

@@ -14,9 +14,10 @@
     ],
     "scripts": {
         "pretest": "eslint .",
-        "test": "npm run test:unit:with-coverage",
+        "test": "npm run test:unit:with-coverage && npm run test:bench",
         "test:unit": "mocha test --recursive --reporter dot",
         "test:unit:with-coverage": "nyc npm run test:unit",
+        "test:bench": "mocha benchmarks",
         "coveralls": "cat ./build/coverage/lcov.info | coveralls",
         "changelog": "pr-log"
     },
@@ -64,7 +65,8 @@
         "branches": 100,
         "exclude": [
             "build",
-            "test"
+            "test",
+            "benchmarks/"
         ],
         "reporter": [
             "lcov",