From 8899b84200ccab2e0b186b2b113fd7cdbd3e7385 Mon Sep 17 00:00:00 2001
From: Ruben Bridgewater <ruben@bridgewater.de>
Date: Sun, 1 Apr 2018 08:41:48 +0200
Subject: [PATCH 1/3] assert: add `rawMessage` to error messages

The `rawMessage` provides the message with a guarantee not to include
any colors.
---
 lib/internal/errors.js                | 1 +
 test/parallel/test-assert-fail.js     | 6 ++++--
 test/pseudo-tty/test-assert-colors.js | 4 ++++
 3 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/lib/internal/errors.js b/lib/internal/errors.js
index f8073d15fe8d49..3fe74d9e5c42ed 100644
--- a/lib/internal/errors.js
+++ b/lib/internal/errors.js
@@ -386,6 +386,7 @@ class AssertionError extends Error {
     this.actual = actual;
     this.expected = expected;
     this.operator = operator;
+    this.rawMessage = lazyInternalUtil().removeColors(this.message);
     Error.captureStackTrace(this, stackStartFn);
   }
 }
diff --git a/test/parallel/test-assert-fail.js b/test/parallel/test-assert-fail.js
index e8336e8f2169ef..fb99075196d3fb 100644
--- a/test/parallel/test-assert-fail.js
+++ b/test/parallel/test-assert-fail.js
@@ -12,7 +12,8 @@ assert.throws(
     message: 'Failed',
     operator: undefined,
     actual: undefined,
-    expected: undefined
+    expected: undefined,
+    rawMessage: 'Failed'
   }
 );
 
@@ -25,7 +26,8 @@ assert.throws(() => {
   message: 'custom message',
   operator: undefined,
   actual: undefined,
-  expected: undefined
+  expected: undefined,
+  rawMessage: 'custom message'
 });
 
 // One arg = Error
diff --git a/test/pseudo-tty/test-assert-colors.js b/test/pseudo-tty/test-assert-colors.js
index 7c5845bdaa271a..2cc298ff8091ba 100644
--- a/test/pseudo-tty/test-assert-colors.js
+++ b/test/pseudo-tty/test-assert-colors.js
@@ -1,6 +1,8 @@
 'use strict';
+// Flags: --expose-internals
 require('../common');
 const assert = require('assert').strict;
+const util = require('internal/util');
 
 try {
   // Activate colors even if the tty does not support colors.
@@ -15,4 +17,6 @@ try {
     '    2\n' +
     '  ]';
   assert.strictEqual(err.message, expected);
+  assert.strictEqual(err.rawMessage, util.removeColors(expected));
+  assert.notStrictEqual(err.message, err.rawMessage);
 }

From 47ab44c8910623fbb081602f5a1e30ca8f1b21ed Mon Sep 17 00:00:00 2001
From: Ruben Bridgewater <ruben@bridgewater.de>
Date: Mon, 2 Apr 2018 18:25:27 +0200
Subject: [PATCH 2/3] fixup: use suggestion

---
 lib/internal/errors.js | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/lib/internal/errors.js b/lib/internal/errors.js
index 3fe74d9e5c42ed..45d5ff17e1d633 100644
--- a/lib/internal/errors.js
+++ b/lib/internal/errors.js
@@ -386,9 +386,21 @@ class AssertionError extends Error {
     this.actual = actual;
     this.expected = expected;
     this.operator = operator;
-    this.rawMessage = lazyInternalUtil().removeColors(this.message);
     Error.captureStackTrace(this, stackStartFn);
   }
+
+  get rawMessage() {
+    return lazyInternalUtil().removeColors(this.message);
+  }
+
+  set rawMessage(value) {
+    Object.defineProperty(this, 'rawMessage', {
+      value,
+      enumerable: true,
+      writable: true,
+      configurable: true
+    });
+  }
 }
 
 // This is defined here instead of using the assert module to avoid a

From 4fbb209fa1ef6c21394297f40048317f770d8840 Mon Sep 17 00:00:00 2001
From: Ruben Bridgewater <ruben@bridgewater.de>
Date: Wed, 4 Apr 2018 15:29:47 +0200
Subject: [PATCH 3/3] fixup: add doc

---
 doc/api/assert.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/doc/api/assert.md b/doc/api/assert.md
index ff06c9250f7da3..b3321897fdbfa7 100644
--- a/doc/api/assert.md
+++ b/doc/api/assert.md
@@ -51,6 +51,7 @@ and:
 * `code` {string} This is always set to the string `ERR_ASSERTION` to indicate
   that the error is actually an assertion error.
 * `operator` {string} Set to the passed in operator value.
+* `rawMessage` {string} Identical to the message, but without any colors.
 
 ```js
 const assert = require('assert');