From 6b5f0c1605b31aade0cd351c04079458051a8e79 Mon Sep 17 00:00:00 2001
From: James <ultrilliam@gmail.com>
Date: Thu, 17 Aug 2023 20:23:22 -0700
Subject: [PATCH] Allow disabling Escape Characters

---
 src/bbcode.ts      | 20 +++++++++++++++++++-
 src/bbcodelexer.ts | 34 ++++++++++++++++++++++------------
 tests/nbbc.test.ts | 14 +++++++++++---
 3 files changed, 52 insertions(+), 16 deletions(-)

diff --git a/src/bbcode.ts b/src/bbcode.ts
index 2ce4c97..6f02e03 100644
--- a/src/bbcode.ts
+++ b/src/bbcode.ts
@@ -189,6 +189,10 @@ export default class BBCode {
      * BBCodeLexer created when calling parse
      */
     protected lexer: BBCodeLexer;
+    /**
+     * Whether to allow Escape Characters in parsing to prevent parsing specific tags or not
+     */
+    protected allowEscape: boolean;
 
     /**
      * Initialize a new instance of the {@link BBCode} class.
@@ -234,6 +238,7 @@ export default class BBCode {
         this.maxEmoji = -1;
         this.escapeContent = true;
         this.stack = [];
+        this.allowEscape = true;
     }
     //-----------------------------------------------------------------------------
     // State control.
@@ -529,6 +534,19 @@ export default class BBCode {
     public getURLTemplate() {
         return this.urlTemplate;
     }
+    /**
+     * Whether to allow BBCode to be escaped or not.
+     */
+    public setAllowEscape(bool: boolean) {
+        this.allowEscape = bool;
+        return this;
+    }
+    /**
+     * Get if escape characters are allowed
+     */
+    public getAllowEscape() {
+        return this.allowEscape;
+    }
     /**
      * Set the template to use for quote tags
      * @param template 
@@ -2527,7 +2545,7 @@ export default class BBCode {
         // and not a character-by-character tokenizer, the structure of the input
         // must be known in advance, which is why the tag marker cannot be changed
         // during the parse.
-        this.lexer = new BBCodeLexer(string, this.tagMarker, this.debug);
+        this.lexer = new BBCodeLexer(string, this.tagMarker, this.debug, this.allowEscape);
         this.lexer.debug = this.debug;
         // If we're fuzzily limiting the text length, see if we need to actually
         // cut it off, or if it's close enough to not be worth the effort.
diff --git a/src/bbcodelexer.ts b/src/bbcodelexer.ts
index a3a37f6..eedbf51 100644
--- a/src/bbcodelexer.ts
+++ b/src/bbcodelexer.ts
@@ -87,6 +87,10 @@ export default class BBCodeLexer {
      * - Nothing, this will disable escape characters
      */
     public escapeRegex: string;
+    /**
+     * Whether to allow Escape Characters or not
+     */
+    public allowEscape: boolean;
 
     /**
      * Instantiate a new instance of the {@link BBCodeLexer} class.
@@ -94,7 +98,7 @@ export default class BBCodeLexer {
      * @param string The string to be broken up into tokens.
      * @param tagMarker The BBCode tag marker.
      */
-    public constructor(string: string, tagMarker = '[', debug: boolean = false) {
+    public constructor(string: string, tagMarker = '[', debug: boolean = false, allowEscape: boolean = true) {
         // First thing we do is to split the input string into tuples of
         // text and tags.  This will make it easy to tokenize.  We define a tag as
         // anything starting with a [, ending with a ], and containing no [ or ] in
@@ -126,7 +130,11 @@ export default class BBCodeLexer {
         const start = regexBeginMarkers[tagMarker];
         this.tagMarker = tagMarker;
         this.endTagMarker = endMarkers[tagMarker];
-        this.escapeRegex = "(?<!\\\\)";
+        this.allowEscape = allowEscape;
+        if (allowEscape)
+            this.escapeRegex = "(?<!\\\\)";
+        else 
+            this.escapeRegex = "";
         // this.input will be an array of tokens, with the special property that
         // the elements strictly alternate between plain text and tags/whitespace/newlines,
         // and that tags always have *two* entries per tag. The first element will
@@ -163,16 +171,18 @@ export default class BBCodeLexer {
             +")";
         this.input = preg_split(this.patMain, string, -1, PREG_SPLIT_DELIM_CAPTURE);
 
-        this.genEscapeRegex = new RegExp(this.patMain.replaceAll(this.escapeRegex, "(\\\\)"), "g");
-        for (const input in this.input) {
-            const value = this.input[input];
-            this.input[input] = value.replace(this.genEscapeRegex, function(match) {
-                // If there's a backslash before the match, remove it
-                if (match[0] === '\\') {
-                    return match.slice(1); // Remove the backslash
-                }
-                return match; 
-            });
+        if (this.allowEscape) {
+            this.genEscapeRegex = new RegExp(this.patMain.replaceAll(this.escapeRegex, "(\\\\)"), "g");
+            for (const input in this.input) {
+                const value = this.input[input];
+                this.input[input] = value.replace(this.genEscapeRegex, function(match) {
+                    // If there's a backslash before the match, remove it
+                    if (match[0] === '\\') {
+                        return match.slice(1); // Remove the backslash
+                    }
+                    return match; 
+                });
+            }
         }
 
         // Patterns for matching specific types of tokens during lexing. (originally contained Dx flags)
diff --git a/tests/nbbc.test.ts b/tests/nbbc.test.ts
index e722a69..488775d 100644
--- a/tests/nbbc.test.ts
+++ b/tests/nbbc.test.ts
@@ -858,6 +858,12 @@ const tests = {
             descr: "Wiki bbcode can't yet be escaped",
             bbcode: "\\[[wiki]] \\[[wiki|test]]",
             html: "\\[[wiki]] \\[[wiki|test]]"
+        },
+        {
+            descr: "BBCode Escape can be disabled",
+            bbcode: "\\[b]test[/b]",
+            html: "\\<b>test</b>",
+            allowEscape: false
         }
     ],
     "Misc Tests": [
@@ -903,7 +909,7 @@ bbcode.addRule('border', {
 bbcode.setLocalImgDir("smileys");
 bbcode.setLocalImgURL("smileys");
 
-console.log = function() {};
+//console.log = function() {};
 console.info = function() {};
 console.warn = function() {};
 console.error = function() {};
@@ -930,9 +936,12 @@ for (const testcat in tests) {
                 if (typeof test['urlforcetarget'] == "string")
                     bbcode.setURLTarget(test['urlforcetarget']);
                 else bbcode.setURLTarget(false);
-                if (test['plainmode'])
+                if (typeof test['plainmode'] !== "undefined")
                     bbcode.setPlainMode(test['plainmode']);
                 else bbcode.setPlainMode(false);
+                if (typeof test["allowEscape"] !== "undefined")
+                    bbcode.setAllowEscape(test["allowEscape"]);
+                else bbcode.setAllowEscape(true);
                 if (test['tag_marker'] == '<') {
                     bbcode.setTagMarker('<');
                     bbcode.setAllowAmpersand(true);
@@ -940,7 +949,6 @@ for (const testcat in tests) {
                 else if (test['tag_marker'])
                     bbcode.setTagMarker(test['tag_marker']);
 
-
                 try {
                     /*if (test['regex']) 
                         expect(new RegExp(test['regex']).test(bbcode.parse(test['bbcode']))).toBe(true);