diff --git a/lib/internal/streams/duplex.js b/lib/internal/streams/duplex.js
index bc92e9021ab57c..295d5c7cf156e8 100644
--- a/lib/internal/streams/duplex.js
+++ b/lib/internal/streams/duplex.js
@@ -41,12 +41,10 @@ const Writable = require('internal/streams/writable');
 ObjectSetPrototypeOf(Duplex.prototype, Readable.prototype);
 ObjectSetPrototypeOf(Duplex, Readable);
 
-{
-  // Allow the keys array to be GC'ed.
-  for (const method of ObjectKeys(Writable.prototype)) {
-    if (!Duplex.prototype[method])
-      Duplex.prototype[method] = Writable.prototype[method];
-  }
+// Allow the keys array to be GC'ed.
+for (const method of ObjectKeys(Writable.prototype)) {
+  if (!Duplex.prototype[method])
+    Duplex.prototype[method] = Writable.prototype[method];
 }
 
 function Duplex(options) {
diff --git a/lib/internal/streams/operators.js b/lib/internal/streams/operators.js
index a6efa92afb7025..bfac0c5e294958 100644
--- a/lib/internal/streams/operators.js
+++ b/lib/internal/streams/operators.js
@@ -12,7 +12,9 @@ const {
 } = require('internal/errors');
 const {
   validateAbortSignal,
+  validateFunction,
   validateInteger,
+  validateObject,
 } = require('internal/validators');
 const { kWeakHandler } = require('internal/event_target');
 const { finished } = require('internal/streams/end-of-stream');
@@ -32,12 +34,9 @@ const kEmpty = Symbol('kEmpty');
 const kEof = Symbol('kEof');
 
 function map(fn, options) {
-  if (typeof fn !== 'function') {
-    throw new ERR_INVALID_ARG_TYPE(
-      'fn', ['Function', 'AsyncFunction'], fn);
-  }
-  if (options != null && typeof options !== 'object') {
-    throw new ERR_INVALID_ARG_TYPE('options', ['Object']);
+  validateFunction(fn, 'fn');
+  if (options != null) {
+    validateObject(options, 'options');
   }
   if (options?.signal != null) {
     validateAbortSignal(options.signal, 'options.signal');
@@ -167,8 +166,8 @@ function map(fn, options) {
 }
 
 function asIndexedPairs(options = undefined) {
-  if (options != null && typeof options !== 'object') {
-    throw new ERR_INVALID_ARG_TYPE('options', ['Object']);
+  if (options != null) {
+    validateObject(options, 'options');
   }
   if (options?.signal != null) {
     validateAbortSignal(options.signal, 'options.signal');
@@ -186,8 +185,8 @@ function asIndexedPairs(options = undefined) {
 }
 
 async function some(fn, options) {
-  if (options != null && typeof options !== 'object') {
-    throw new ERR_INVALID_ARG_TYPE('options', ['Object']);
+  if (options != null) {
+    validateObject(options, 'options');
   }
   if (options?.signal != null) {
     validateAbortSignal(options.signal, 'options.signal');
@@ -216,10 +215,7 @@ async function some(fn, options) {
 }
 
 async function every(fn, options) {
-  if (typeof fn !== 'function') {
-    throw new ERR_INVALID_ARG_TYPE(
-      'fn', ['Function', 'AsyncFunction'], fn);
-  }
+  validateFunction(fn, 'fn');
   // https://en.wikipedia.org/wiki/De_Morgan%27s_laws
   return !(await some.call(this, async (...args) => {
     return !(await fn(...args));
@@ -227,10 +223,7 @@ async function every(fn, options) {
 }
 
 async function forEach(fn, options) {
-  if (typeof fn !== 'function') {
-    throw new ERR_INVALID_ARG_TYPE(
-      'fn', ['Function', 'AsyncFunction'], fn);
-  }
+  validateFunction(fn, 'fn');
   async function forEachFn(value, options) {
     await fn(value, options);
     return kEmpty;
@@ -240,10 +233,7 @@ async function forEach(fn, options) {
 }
 
 function filter(fn, options) {
-  if (typeof fn !== 'function') {
-    throw new ERR_INVALID_ARG_TYPE(
-      'fn', ['Function', 'AsyncFunction'], fn);
-  }
+  validateFunction(fn, 'fn');
   async function filterFn(value, options) {
     if (await fn(value, options)) {
       return value;
@@ -263,12 +253,9 @@ class ReduceAwareErrMissingArgs extends ERR_MISSING_ARGS {
 }
 
 async function reduce(reducer, initialValue, options) {
-  if (typeof reducer !== 'function') {
-    throw new ERR_INVALID_ARG_TYPE(
-      'reducer', ['Function', 'AsyncFunction'], reducer);
-  }
-  if (options != null && typeof options !== 'object') {
-    throw new ERR_INVALID_ARG_TYPE('options', ['Object']);
+  validateFunction(fn, 'fn');
+  if (options != null) {
+    validateObject(options, 'options');
   }
   if (options?.signal != null) {
     validateAbortSignal(options.signal, 'options.signal');
@@ -311,8 +298,8 @@ async function reduce(reducer, initialValue, options) {
 }
 
 async function toArray(options) {
-  if (options != null && typeof options !== 'object') {
-    throw new ERR_INVALID_ARG_TYPE('options', ['Object']);
+  if (options != null) {
+    validateObject(options, 'options');
   }
   if (options?.signal != null) {
     validateAbortSignal(options.signal, 'options.signal');
@@ -351,8 +338,8 @@ function toIntegerOrInfinity(number) {
 }
 
 function drop(number, options = undefined) {
-  if (options != null && typeof options !== 'object') {
-    throw new ERR_INVALID_ARG_TYPE('options', ['Object']);
+  if (options != null) {
+    validateObject(options, 'options');
   }
   if (options?.signal != null) {
     validateAbortSignal(options.signal, 'options.signal');
@@ -375,8 +362,8 @@ function drop(number, options = undefined) {
 }
 
 function take(number, options = undefined) {
-  if (options != null && typeof options !== 'object') {
-    throw new ERR_INVALID_ARG_TYPE('options', ['Object']);
+  if (options != null) {
+    validateObject(options, 'options');
   }
   if (options?.signal != null) {
     validateAbortSignal(options.signal, 'options.signal');
diff --git a/lib/internal/streams/readable.js b/lib/internal/streams/readable.js
index d0125386c8ae8e..eaa3121ef6f278 100644
--- a/lib/internal/streams/readable.js
+++ b/lib/internal/streams/readable.js
@@ -787,7 +787,7 @@ Readable.prototype.pipe = function(dest, pipeOpts) {
     debug('onerror', er);
     unpipe();
     dest.removeListener('error', onerror);
-    if (EE.listenerCount(dest, 'error') === 0) {
+    if (dest.listenerCount('error') === 0) {
       const s = dest._writableState || dest._readableState;
       if (s && !s.errorEmitted) {
         // User incorrectly emitted 'error' directly on the stream.
@@ -852,7 +852,7 @@ function pipeOnDrain(src, dest) {
     }
 
     if ((!state.awaitDrainWriters || state.awaitDrainWriters.size === 0) &&
-      EE.listenerCount(src, 'data')) {
+      src.listenerCount('data')) {
       state.flowing = true;
       flow(src);
     }