From 62bedde23d2229f722d382075f32ce8a577bd627 Mon Sep 17 00:00:00 2001
From: ridiculousfish <corydoras@ridiculousfish.com>
Date: Sat, 25 Nov 2017 01:07:56 -0800
Subject: [PATCH] [muparser] Clean up error handling in ParserTokenReader

---
 muparser-2.2.5/include/muParserTokenReader.h | 11 +++++++++--
 muparser-2.2.5/src/muParserBase.cpp          |  3 ++-
 muparser-2.2.5/src/muParserTokenReader.cpp   | 17 +++++++++--------
 3 files changed, 20 insertions(+), 11 deletions(-)

diff --git a/muparser-2.2.5/include/muParserTokenReader.h b/muparser-2.2.5/include/muParserTokenReader.h
index c9e46c81b..9277c06a5 100644
--- a/muparser-2.2.5/include/muParserTokenReader.h
+++ b/muparser-2.2.5/include/muParserTokenReader.h
@@ -68,6 +68,13 @@ class ParserTokenReader final {
     void ReInit();
     token_type ReadNextToken();
 
+    /// \return the first error (if any), clearing it.
+    OptionalError acquireFirstError() {
+        OptionalError ret = std::move(firstError_);
+        firstError_ = OptionalError{};
+        return ret;
+    }
+
    private:
     /** \brief Syntax codes.
 
@@ -113,8 +120,7 @@ class ParserTokenReader final {
     bool IsStrVarTok(token_type &a_Tok);
     bool IsUndefVarTok(token_type &a_Tok);
     bool IsString(token_type &a_Tok);
-    void Error(EErrorCodes a_iErrc, int a_iPos = -1,
-               const string_type &a_sTok = string_type()) const;
+    bool Error(EErrorCodes a_iErrc, int a_iPos = -1, const string_type &a_sTok = string_type());
 
     token_type &SaveBeforeReturn(const token_type &tok);
 
@@ -124,6 +130,7 @@ class ParserTokenReader final {
     int m_iSynFlags = 0;
     bool m_bIgnoreUndefVar = false;
 
+    OptionalError firstError_;  /// The first error reported during parsing.
     const funmap_type *m_pFunDef = nullptr;
     const funmap_type *m_pPostOprtDef = nullptr;
     const funmap_type *m_pInfixOprtDef = nullptr;
diff --git a/muparser-2.2.5/src/muParserBase.cpp b/muparser-2.2.5/src/muParserBase.cpp
index ba0a2c893..a617b0544 100644
--- a/muparser-2.2.5/src/muParserBase.cpp
+++ b/muparser-2.2.5/src/muParserBase.cpp
@@ -1040,8 +1040,9 @@ OptionalError ParserBase::CreateRPN() const {
 
     for (;;) {
         opt = m_pTokenReader->ReadNextToken();
+        OptionalError oerr = m_pTokenReader->acquireFirstError();
+        if (oerr.has_error()) return oerr;
 
-        OptionalError oerr;
         switch (opt.GetCode()) {
             //
             // Next three are different kind of value entries
diff --git a/muparser-2.2.5/src/muParserTokenReader.cpp b/muparser-2.2.5/src/muParserTokenReader.cpp
index 34c6cd1f6..67a1b0b37 100644
--- a/muparser-2.2.5/src/muParserTokenReader.cpp
+++ b/muparser-2.2.5/src/muParserTokenReader.cpp
@@ -162,14 +162,14 @@ ParserTokenReader::token_type ParserTokenReader::ReadNextToken() {
 
     // Check for unknown token
     //
-    // !!! From this point on there is no exit without an exception possible...
+    // !!! From this point on there is no exit without an error possible...
     //
     string_type strTok;
     int iEnd = ExtractToken(m_pParser->ValidNameChars(), strTok, m_iPos);
     if (iEnd != m_iPos) Error(ecUNASSIGNABLE_TOKEN, m_iPos, strTok);
 
     Error(ecUNASSIGNABLE_TOKEN, m_iPos, m_strFormula.substr(m_iPos));
-    return token_type();  // never reached
+    return token_type();
 }
 
 //---------------------------------------------------------------------------
@@ -723,17 +723,18 @@ bool ParserTokenReader::IsString(token_type &a_Tok) {
 }
 
 //---------------------------------------------------------------------------
-/** \brief Create an error containing the parse error position.
-
-  This function will create an Parser Exception object containing the error text and its position.
+/** \brief Create an error containing the parse error position. Store it in parseError_, if not
+  already set.
 
   \param a_iErrc [in] The error code of type #EErrorCodes.
   \param a_iPos [in] The position where the error was detected.
   \param a_strTok [in] The token string representation associated with the error.
-  \throw ParserException always throws thats the only purpose of this function.
 */
-void ParserTokenReader::Error(EErrorCodes a_iErrc, int a_iPos, const string_type &a_sTok) const {
-    m_pParser->Error(a_iErrc, a_iPos, a_sTok);
+bool ParserTokenReader::Error(EErrorCodes a_iErrc, int a_iPos, const string_type &a_sTok) {
+    if (!firstError_.has_error()) {
+        firstError_ = m_pParser->Error(a_iErrc, a_iPos, a_sTok);
+    }
+    return false;
 }
 
 //---------------------------------------------------------------------------