crypto: remove DEFAULT_ENCODING

Citing 76b0bdf from 2012, "only use
this as a temporary measure."

Getting or setting DEFAULT_ENCODING has emitted a warning ever since
Node.js 10, so it seems appropriate to remove it in Node.js 20 five
years later. The last Node.js version that did not emit a warning
reached its end-of-life status at the end of 2019.

This commit only removes the public API so that the change can land in
time for Node.js 20.

Refs: nodejs/node-v0.x-archive#4179
Refs: #18333
PR-URL: #47182
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Filip Skokan <panva.ip@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Beth Griggs <bethanyngriggs@gmail.com>
Reviewed-By: Erick Wendel <erick.workspace@gmail.com>
Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com>

doc/api/crypto.md

@@ -2878,26 +2878,6 @@ An object containing commonly used constants for crypto and security related
 operations. The specific constants currently defined are described in
 [Crypto constants][].
 
-### `crypto.DEFAULT_ENCODING`
-
-<!-- YAML
-added: v0.9.3
-deprecated: v10.0.0
--->
-
-> Stability: 0 - Deprecated
-
-The default encoding to use for functions that can take either strings
-or [buffers][`Buffer`]. The default value is `'buffer'`, which makes methods
-default to [`Buffer`][] objects.
-
-The `crypto.DEFAULT_ENCODING` mechanism is provided for backward compatibility
-with legacy programs that expect `'latin1'` to be the default encoding.
-
-New applications should expect the default to be `'buffer'`.
-
-This property is deprecated.
-
 ### `crypto.fips`
 
 <!-- YAML

doc/api/deprecations.md

@@ -1864,14 +1864,18 @@ bits are allowed. Authentication tags of other lengths are invalid per
 
 <!-- YAML
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/47182
+    description: End-of-Life.
   - version: v10.0.0
     pr-url: https://github.com/nodejs/node/pull/18333
     description: Runtime deprecation.
 -->
 
-Type: Runtime
+Type: End-of-Life
 
-The [`crypto.DEFAULT_ENCODING`][] property is deprecated.
+The `crypto.DEFAULT_ENCODING` property only existed for compatibility with
+Node.js releases prior to versions 0.9.3 and has been removed.
 
 ### DEP0092: Top-level `this` bound to `module.exports`
 
@@ -3388,7 +3392,6 @@ be added when a function is bound to an `AsyncResource`.
 [`console.error()`]: console.md#consoleerrordata-args
 [`console.log()`]: console.md#consolelogdata-args
 [`crypto.Certificate()` constructor]: crypto.md#legacy-api
-[`crypto.DEFAULT_ENCODING`]: crypto.md#cryptodefault_encoding
 [`crypto.createCipher()`]: crypto.md#cryptocreatecipheralgorithm-password-options
 [`crypto.createCipheriv()`]: crypto.md#cryptocreatecipherivalgorithm-key-iv-options
 [`crypto.createDecipher()`]: crypto.md#cryptocreatedecipheralgorithm-password-options

lib/crypto.js

@@ -114,9 +114,7 @@ const {
 const {
   getCiphers,
   getCurves,
-  getDefaultEncoding,
   getHashes,
-  setDefaultEncoding,
   setEngine,
   secureHeapUsed,
 } = require('internal/crypto/util');
@@ -356,15 +354,6 @@ ObjectDefineProperties(module.exports, {
     get: getFips,
     set: setFips,
   },
-  DEFAULT_ENCODING: {
-    __proto__: null,
-    enumerable: false,
-    configurable: true,
-    get: deprecate(getDefaultEncoding,
-                   'crypto.DEFAULT_ENCODING is deprecated.', 'DEP0091'),
-    set: deprecate(setDefaultEncoding,
-                   'crypto.DEFAULT_ENCODING is deprecated.', 'DEP0091'),
-  },
   constants: {
     __proto__: null,
     configurable: false,

lib/internal/crypto/util.js

@@ -74,14 +74,9 @@ const {
 const kHandle = Symbol('kHandle');
 const kKeyObject = Symbol('kKeyObject');
 
-let defaultEncoding = 'buffer';
-
-function setDefaultEncoding(val) {
-  defaultEncoding = val;
-}
-
+// TODO(tniessen): remove all call sites and this function
 function getDefaultEncoding() {
-  return defaultEncoding;
+  return 'buffer';
 }
 
 // This is here because many functions accepted binary strings without
@@ -561,7 +556,6 @@ module.exports = {
   getHashes,
   kHandle,
   kKeyObject,
-  setDefaultEncoding,
   setEngine,
   toBuf,
 

test/parallel/test-crypto-authenticated.js

@@ -29,8 +29,6 @@ const crypto = require('crypto');
 const { inspect } = require('util');
 const fixtures = require('../common/fixtures');
 
-crypto.DEFAULT_ENCODING = 'buffer';
-
 //
 // Test authenticated encryption modes.
 //
@@ -74,7 +72,6 @@ const expectedWarnings = common.hasFipsCrypto ?
   ];
 
 const expectedDeprecationWarnings = [
-  ['crypto.DEFAULT_ENCODING is deprecated.', 'DEP0091'],
   ['crypto.createCipher is deprecated.', 'DEP0106'],
 ];