Text show as formula when USE_MATHJAX=YES (#7697)

When having a line of code like:
```
callback_check = re.compile(r'([^\(]*\(.*)(\* *)(\).*\(.*\))')
```
this is seen as an incomplete formula when using MathJax, the `\(` is seen as start of a MathJax  formula.
Replacing the backslash by the corresponding code `\` didn't work as this is already translated by the bowser and still picked up by MathJax, so we need `‍` to separate the backslash and the bracket without any spacing.

2 files changed, 22 insertions, 0 deletions

diff --git a/src/htmldocvisitor.cpp b/src/htmldocvisitor.cpp
index bb35cae..ea2dffb 100644
--- a/src/htmldocvisitor.cpp
+++ b/src/htmldocvisitor.cpp
@@ -2226,6 +2226,11 @@ void HtmlDocVisitor::filter(const char *str)
       case '<':  m_t << "&lt;"; break;
       case '>':  m_t << "&gt;"; break;
       case '&':  m_t << "&amp;"; break;
+      case '\\': if ((*p == '(') || (*p == ')'))
+                   m_t << "\\&zwj;" << *p++;
+                 else
+                   m_t << c;
+                 break;
       default:   m_t << c;
     }
   }
@@ -2247,6 +2252,11 @@ void HtmlDocVisitor::filterQuotedCdataAttr(const char* str)
       case '"':  m_t << "&quot;"; break;
       case '<':  m_t << "&lt;"; break;
       case '>':  m_t << "&gt;"; break;
+      case '\\': if ((*p == '(') || (*p == ')'))
+                   m_t << "\\&zwj;" << *p++;
+                 else
+                   m_t << c;
+                 break;
       default:   m_t << c;
     }
   }
diff --git a/src/htmlgen.cpp b/src/htmlgen.cpp
index ac42a6a..b157881 100644
--- a/src/htmlgen.cpp
+++ b/src/htmlgen.cpp
@@ -668,6 +668,10 @@ void HtmlCodeGenerator::codify(const char *str)
                      { m_t << "&lt;"; p++; }
                    else if (*p=='>')
                      { m_t << "&gt;"; p++; }
+		   else if (*p=='(')
+                     { m_t << "\\&zwj;("; m_col++;p++; }
+                   else if (*p==')')
+                     { m_t << "\\&zwj;)"; m_col++;p++; }
                    else
                      m_t << "\\";
                    m_col++;
@@ -702,6 +706,10 @@ void HtmlCodeGenerator::docify(const char *str)
                      { m_t << "&lt;"; p++; }
                    else if (*p=='>')
                      { m_t << "&gt;"; p++; }
+		   else if (*p=='(')
+                     { m_t << "\\&zwj;("; p++; }
+                   else if (*p==')')
+                     { m_t << "\\&zwj;)"; p++; }
                    else
                      m_t << "\\";
                    break;
@@ -1502,6 +1510,10 @@ void HtmlGenerator::docify(const char *str,bool inHtmlComment)
                      { t << "&lt;"; p++; }
                    else if (*p=='>')
                      { t << "&gt;"; p++; }
+		   else if (*p=='(')
+                     { t << "\\&zwj;("; p++; }
+                   else if (*p==')')
+                     { t << "\\&zwj;)"; p++; }
                    else
                      t << "\\";
                    break;