diff --git a/.eslintrc.js b/.eslintrc.js
index 770ba3e138d5..90ac9b647148 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -371,8 +371,12 @@ const base = {
   'unicorn/no-unused-properties': 'error',
   // enforce lowercase identifier and uppercase value for number literals
   'unicorn/number-literal-case': 'error',
+  // prefer `Array#indexOf` over `Array#findIndex`` when looking for the index of an item
+  'unicorn/prefer-array-index-of': 'error',
   // prefer default parameters over reassignment
   'unicorn/prefer-default-parameters': 'error',
+  // prefer `RegExp#test` over `String#match` and `RegExp#exec`
+  'unicorn/prefer-regexp-test': 'error',
   // prefer `String#slice` over `String#{ substr, substring }`
   'unicorn/prefer-string-slice': 'error',
 
diff --git a/package.json b/package.json
index b7b2aff0d912..0ed5835c8b61 100644
--- a/package.json
+++ b/package.json
@@ -34,7 +34,7 @@
     "eslint-plugin-optimize-regex": "^1.2.0",
     "eslint-plugin-qunit": "^5.2.0",
     "eslint-plugin-sonarjs": "~0.5.0",
-    "eslint-plugin-unicorn": "^25.0.1",
+    "eslint-plugin-unicorn": "^26.0.0",
     "grunt": "^1.3.0",
     "grunt-cli": "^1.3.2",
     "grunt-contrib-clean": "^2.0.0",
diff --git a/tests/pure/es.promise.js b/tests/pure/es.promise.js
index 2728a8779620..ed63356f1a32 100644
--- a/tests/pure/es.promise.js
+++ b/tests/pure/es.promise.js
@@ -203,7 +203,7 @@ QUnit.test('Promise.all', assert => {
   let FakePromise2 = FakePromise1[Symbol.species] = function (executor) {
     executor(() => { /* empty */ }, () => { /* empty */ });
   };
-  FakePromise1.resolve = FakePromise2.resolve = bind(Promise.resolve, Promise);
+  FakePromise1.resolve = FakePromise2.resolve = bind(resolve, Promise);
   assert.ok(all.call(FakePromise1, [1, 2, 3]) instanceof FakePromise1, 'subclassing, `this` pattern');
   FakePromise1 = function () { /* empty */ };
   FakePromise2 = function (executor) {
@@ -212,7 +212,7 @@ QUnit.test('Promise.all', assert => {
   const FakePromise3 = function (executor) {
     executor(() => { /* empty */ }, null);
   };
-  FakePromise1.resolve = FakePromise2.resolve = FakePromise3.resolve = bind(Promise.resolve, Promise);
+  FakePromise1.resolve = FakePromise2.resolve = FakePromise3.resolve = bind(resolve, Promise);
   assert.throws(() => {
     all.call(FakePromise1, [1, 2, 3]);
   }, 'NewPromiseCapability validations, #1');
@@ -263,7 +263,7 @@ QUnit.test('Promise.race', assert => {
   let FakePromise2 = FakePromise1[Symbol.species] = function (executor) {
     executor(() => { /* empty */ }, () => { /* empty */ });
   };
-  FakePromise1.resolve = FakePromise2.resolve = bind(Promise.resolve, Promise);
+  FakePromise1.resolve = FakePromise2.resolve = bind(resolve, Promise);
   assert.ok(race.call(FakePromise1, [1, 2, 3]) instanceof FakePromise1, 'subclassing, `this` pattern');
   FakePromise1 = function () { /* empty */ };
   FakePromise2 = function (executor) {
@@ -272,7 +272,7 @@ QUnit.test('Promise.race', assert => {
   const FakePromise3 = function (executor) {
     executor(() => { /* empty */ }, null);
   };
-  FakePromise1.resolve = FakePromise2.resolve = FakePromise3.resolve = bind(Promise.resolve, Promise);
+  FakePromise1.resolve = FakePromise2.resolve = FakePromise3.resolve = bind(resolve, Promise);
   assert.throws(() => {
     race.call(FakePromise1, [1, 2, 3]);
   }, 'NewPromiseCapability validations, #1');
diff --git a/tests/tests/es.array.find-index.js b/tests/tests/es.array.find-index.js
index b05982845cfa..58df51faaf8c 100644
--- a/tests/tests/es.array.find-index.js
+++ b/tests/tests/es.array.find-index.js
@@ -16,7 +16,9 @@ QUnit.test('Array#findIndex', assert => {
     assert.same(that, array, 'correct link to array in callback');
     assert.same(this, context, 'correct callback context');
   }, context);
+  // eslint-disable-next-line unicorn/prefer-array-index-of
   assert.same([1, 3, NaN, 42, {}].findIndex(it => it === 42), 3);
+  // eslint-disable-next-line unicorn/prefer-array-index-of
   assert.same([1, 3, NaN, 42, {}].findIndex(it => it === 43), -1);
   if (STRICT) {
     assert.throws(() => findIndex.call(null, 0), TypeError);
diff --git a/tests/tests/es.promise.js b/tests/tests/es.promise.js
index 4a6b5bff0fd7..4c667f6c2142 100644
--- a/tests/tests/es.promise.js
+++ b/tests/tests/es.promise.js
@@ -214,7 +214,7 @@ QUnit.test('Promise.all', assert => {
   FakePromise2 = FakePromise1[Symbol.species] = function (executor) {
     executor(() => { /* empty */ }, () => { /* empty */ });
   };
-  FakePromise1.resolve = FakePromise2.resolve = Promise.resolve.bind(Promise);
+  FakePromise1.resolve = FakePromise2.resolve = resolve.bind(Promise);
   assert.ok(all.call(FakePromise1, [1, 2, 3]) instanceof FakePromise1, 'subclassing, `this` pattern');
   FakePromise1 = function () { /* empty */ };
   FakePromise2 = function (executor) {
@@ -223,7 +223,7 @@ QUnit.test('Promise.all', assert => {
   const FakePromise3 = function (executor) {
     executor(() => { /* empty */ }, null);
   };
-  FakePromise1.resolve = FakePromise2.resolve = FakePromise3.resolve = Promise.resolve.bind(Promise);
+  FakePromise1.resolve = FakePromise2.resolve = FakePromise3.resolve = resolve.bind(Promise);
   assert.throws(() => {
     all.call(FakePromise1, [1, 2, 3]);
   }, 'NewPromiseCapability validations, #1');
@@ -278,7 +278,7 @@ QUnit.test('Promise.race', assert => {
   FakePromise2 = FakePromise1[Symbol.species] = function (executor) {
     executor(() => { /* empty */ }, () => { /* empty */ });
   };
-  FakePromise1.resolve = FakePromise2.resolve = Promise.resolve.bind(Promise);
+  FakePromise1.resolve = FakePromise2.resolve = resolve.bind(Promise);
   assert.ok(race.call(FakePromise1, [1, 2, 3]) instanceof FakePromise1, 'subclassing, `this` pattern');
   FakePromise1 = function () { /* empty */ };
   FakePromise2 = function (executor) {
@@ -287,7 +287,7 @@ QUnit.test('Promise.race', assert => {
   const FakePromise3 = function (executor) {
     executor(() => { /* empty */ }, null);
   };
-  FakePromise1.resolve = FakePromise2.resolve = FakePromise3.resolve = Promise.resolve.bind(Promise);
+  FakePromise1.resolve = FakePromise2.resolve = FakePromise3.resolve = resolve.bind(Promise);
   assert.throws(() => {
     race.call(FakePromise1, [1, 2, 3]);
   }, 'NewPromiseCapability validations, #1');
diff --git a/tests/tests/es.string.trim-end.js b/tests/tests/es.string.trim-end.js
index 11407275bbfa..23e82016c97e 100644
--- a/tests/tests/es.string.trim-end.js
+++ b/tests/tests/es.string.trim-end.js
@@ -17,13 +17,13 @@ QUnit.test('String#trimRight', assert => {
 });
 
 QUnit.test('String#trimEnd', assert => {
-  const { trimEnd } = String.prototype;
+  const { trimEnd, trimRight } = String.prototype;
   assert.isFunction(trimEnd);
   assert.arity(trimEnd, 0);
   assert.name(trimEnd, 'trimEnd');
   assert.looksNative(trimEnd);
   assert.nonEnumerable(String.prototype, 'trimEnd');
-  assert.same(trimEnd, String.prototype.trimRight, 'same #trimRight');
+  assert.same(trimEnd, trimRight, 'same #trimRight');
   assert.strictEqual(' \n  q w e \n  '.trimEnd(), ' \n  q w e', 'removes whitespaces at right side of string');
   assert.strictEqual(WHITESPACES.trimEnd(), '', 'removes all whitespaces');
   assert.strictEqual('\u200B\u0085'.trimEnd(), '\u200B\u0085', "shouldn't remove this symbols");
diff --git a/tests/tests/es.string.trim-start.js b/tests/tests/es.string.trim-start.js
index 2bfd7843f164..de3f936f4315 100644
--- a/tests/tests/es.string.trim-start.js
+++ b/tests/tests/es.string.trim-start.js
@@ -17,13 +17,13 @@ QUnit.test('String#trimLeft', assert => {
 });
 
 QUnit.test('String#trimStart', assert => {
-  const { trimStart } = String.prototype;
+  const { trimStart, trimLeft } = String.prototype;
   assert.isFunction(trimStart);
   assert.arity(trimStart, 0);
   assert.name(trimStart, 'trimStart');
   assert.looksNative(trimStart);
   assert.nonEnumerable(String.prototype, 'trimStart');
-  assert.same(trimStart, String.prototype.trimLeft, 'same #trimLeft');
+  assert.same(trimStart, trimLeft, 'same #trimLeft');
   assert.strictEqual(' \n  q w e \n  '.trimStart(), 'q w e \n  ', 'removes whitespaces at left side of string');
   assert.strictEqual(WHITESPACES.trimStart(), '', 'removes all whitespaces');
   assert.strictEqual('\u200B\u0085'.trimStart(), '\u200B\u0085', "shouldn't remove this symbols");
diff --git a/tests/tests/es.typed-array.find-index.js b/tests/tests/es.typed-array.find-index.js
index 316c6951803f..f4b7ae569235 100644
--- a/tests/tests/es.typed-array.find-index.js
+++ b/tests/tests/es.typed-array.find-index.js
@@ -19,6 +19,7 @@ if (DESCRIPTORS) QUnit.test('%TypedArrayPrototype%.findIndex', assert => {
       assert.same(this, context, 'correct callback context');
     }, context);
     assert.same(new TypedArray([1, 2, 3]).findIndex(it => !(it % 2)), 1);
+    // eslint-disable-next-line unicorn/prefer-array-index-of
     assert.same(new TypedArray([1, 2, 3]).findIndex(it => it === 4), -1);
     let values = '';
     let keys = '';
diff --git a/tests/tests/esnext.math.deg-per-rad.js b/tests/tests/esnext.math.deg-per-rad.js
index 96290ef2cc68..a3658a8d904c 100644
--- a/tests/tests/esnext.math.deg-per-rad.js
+++ b/tests/tests/esnext.math.deg-per-rad.js
@@ -1,6 +1,6 @@
 QUnit.test('Math.DEG_PER_RAD', assert => {
-  const { DEG_PER_RAD } = Math;
+  const { DEG_PER_RAD, PI } = Math;
   assert.ok('DEG_PER_RAD' in Math, 'DEG_PER_RAD in Math');
   assert.nonEnumerable(Math, 'DEG_PER_RAD');
-  assert.strictEqual(DEG_PER_RAD, Math.PI / 180, 'Is Math.PI / 180');
+  assert.strictEqual(DEG_PER_RAD, PI / 180, 'Is Math.PI / 180');
 });
diff --git a/tests/tests/esnext.math.degrees.js b/tests/tests/esnext.math.degrees.js
index 38aab5efb86b..b2cd1199624f 100644
--- a/tests/tests/esnext.math.degrees.js
+++ b/tests/tests/esnext.math.degrees.js
@@ -1,12 +1,12 @@
 QUnit.test('Math.degrees', assert => {
-  const { degrees } = Math;
+  const { degrees, PI } = Math;
   assert.isFunction(degrees);
   assert.name(degrees, 'degrees');
   assert.arity(degrees, 1);
   assert.looksNative(degrees);
   assert.nonEnumerable(Math, 'degrees');
   assert.same(degrees(0), 0);
-  assert.same(degrees(Math.PI / 2), 90);
-  assert.same(degrees(Math.PI), 180);
-  assert.same(degrees(3 * Math.PI / 2), 270);
+  assert.same(degrees(PI / 2), 90);
+  assert.same(degrees(PI), 180);
+  assert.same(degrees(3 * PI / 2), 270);
 });
diff --git a/tests/tests/esnext.math.rad-per-deg.js b/tests/tests/esnext.math.rad-per-deg.js
index 56d1f3b249b4..b05553571c9a 100644
--- a/tests/tests/esnext.math.rad-per-deg.js
+++ b/tests/tests/esnext.math.rad-per-deg.js
@@ -1,6 +1,6 @@
 QUnit.test('Math.RAD_PER_DEG', assert => {
-  const { RAD_PER_DEG } = Math;
+  const { RAD_PER_DEG, PI } = Math;
   assert.ok('RAD_PER_DEG' in Math, 'RAD_PER_DEG in Math');
   assert.nonEnumerable(Math, 'RAD_PER_DEG');
-  assert.strictEqual(RAD_PER_DEG, 180 / Math.PI, 'Is 180 / Math.PI');
+  assert.strictEqual(RAD_PER_DEG, 180 / PI, 'Is 180 / Math.PI');
 });
diff --git a/tests/tests/esnext.math.radians.js b/tests/tests/esnext.math.radians.js
index 9434cf8735d6..42d64aef7e1d 100644
--- a/tests/tests/esnext.math.radians.js
+++ b/tests/tests/esnext.math.radians.js
@@ -1,12 +1,12 @@
 QUnit.test('Math.radians', assert => {
-  const { radians } = Math;
+  const { radians, PI } = Math;
   assert.isFunction(radians);
   assert.name(radians, 'radians');
   assert.arity(radians, 1);
   assert.looksNative(radians);
   assert.nonEnumerable(Math, 'radians');
   assert.same(radians(0), 0);
-  assert.same(radians(90), Math.PI / 2);
-  assert.same(radians(180), Math.PI);
-  assert.same(radians(270), 3 * Math.PI / 2);
+  assert.same(radians(90), PI / 2);
+  assert.same(radians(180), PI);
+  assert.same(radians(270), 3 * PI / 2);
 });