diff --git a/packages/compiler-core/src/parse.ts b/packages/compiler-core/src/parse.ts
index b937b145881..5cdd9ae3eda 100644
--- a/packages/compiler-core/src/parse.ts
+++ b/packages/compiler-core/src/parse.ts
@@ -1044,7 +1044,7 @@ function parseTextData(
   if (
     mode === TextModes.RAWTEXT ||
     mode === TextModes.CDATA ||
-    rawText.indexOf('&') === -1
+    !rawText.includes('&')
   ) {
     return rawText
   } else {
diff --git a/packages/runtime-core/src/compat/renderHelpers.ts b/packages/runtime-core/src/compat/renderHelpers.ts
index dd4feee1d1b..aa156c11a40 100644
--- a/packages/runtime-core/src/compat/renderHelpers.ts
+++ b/packages/runtime-core/src/compat/renderHelpers.ts
@@ -157,7 +157,7 @@ export function legacyCheckKeyCodes(
 
 function isKeyNotMatch<T>(expect: T | T[], actual: T): boolean {
   if (isArray(expect)) {
-    return expect.indexOf(actual) === -1
+    return !expect.includes(actual)
   } else {
     return expect !== actual
   }
diff --git a/packages/runtime-core/src/components/KeepAlive.ts b/packages/runtime-core/src/components/KeepAlive.ts
index 7a9419f3b63..15dbff52913 100644
--- a/packages/runtime-core/src/components/KeepAlive.ts
+++ b/packages/runtime-core/src/components/KeepAlive.ts
@@ -345,7 +345,7 @@ function matches(pattern: MatchPattern, name: string): boolean {
   if (isArray(pattern)) {
     return pattern.some((p: string | RegExp) => matches(p, name))
   } else if (isString(pattern)) {
-    return pattern.split(',').indexOf(name) > -1
+    return pattern.split(',').includes(name)
   } else if (pattern.test) {
     return pattern.test(name)
   }
diff --git a/scripts/setupJestEnv.ts b/scripts/setupJestEnv.ts
index cccca10d57c..bdeab74d217 100644
--- a/scripts/setupJestEnv.ts
+++ b/scripts/setupJestEnv.ts
@@ -1,7 +1,7 @@
 expect.extend({
   toHaveBeenWarned(received: string) {
     asserted.add(received)
-    const passed = warn.mock.calls.some(args => args[0].indexOf(received) > -1)
+    const passed = warn.mock.calls.some(args => args[0].includes(received))
     if (passed) {
       return {
         pass: true,
@@ -23,7 +23,7 @@ expect.extend({
   toHaveBeenWarnedLast(received: string) {
     asserted.add(received)
     const passed =
-      warn.mock.calls[warn.mock.calls.length - 1][0].indexOf(received) > -1
+      warn.mock.calls[warn.mock.calls.length - 1][0].includes(received)
     if (passed) {
       return {
         pass: true,
@@ -43,7 +43,7 @@ expect.extend({
     asserted.add(received)
     let found = 0
     warn.mock.calls.forEach(args => {
-      if (args[0].indexOf(received) > -1) {
+      if (args[0].includes(received)) {
         found++
       }
     })
@@ -78,7 +78,7 @@ afterEach(() => {
     .map(args => args[0])
     .filter(received => {
       return !assertedArray.some(assertedMsg => {
-        return received.indexOf(assertedMsg) > -1
+        return received.includes(assertedMsg)
       })
     })
   warn.mockRestore()