[LyX/2.3.x] tex2lyx: fix import of umlauts and ß in math (#12739)

[Juergen Spitzmueller]

commit 624a1be0723abb1398dad5cf486bd075fd138b2f
Author: Juergen Spitzmueller <spitz at lyx.org>
Date:   Fri Apr 14 19:13:23 2023 +0200

    tex2lyx: fix import of umlauts and ß in math (#12739)
---
 src/tex2lyx/math.cpp |   24 ++++++++++++++++--------
 status.23x           |    5 ++---
 2 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/src/tex2lyx/math.cpp b/src/tex2lyx/math.cpp
index 9fddeea..7cdb810 100644
--- a/src/tex2lyx/math.cpp
+++ b/src/tex2lyx/math.cpp
@@ -213,17 +213,25 @@ void parse_math(Parser & p, ostream & os, unsigned flags, const mode_type mode)
 
 		else if (t.cs() == "\"") {
 			string const name = p.verbatim_item();
-			     if (name == "a") os << '\xe4';
-			else if (name == "o") os << '\xf6';
-			else if (name == "u") os << '\xfc';
-			else if (name == "A") os << '\xc4';
-			else if (name == "O") os << '\xd6';
-			else if (name == "U") os << '\xdc';
-			else os << "\"{" << name << "}";
+			LYXERR0("name: " << name);
+			if (name == "a")
+				os << "ä";
+			else if (name == "o")
+				os << "ö";
+			else if (name == "u")
+				os << "ü";
+			else if (name == "A")
+				os << "Ä";
+			else if (name == "O")
+				os << "Ö";
+			else if (name == "U")
+				os << "Ü";
+			else
+				os << "\"{" << name << "}";
 		}
 
 		else if (t.cs() == "ss")
-			os << "\xdf";
+			os << "ß";
 
 		else if (t.cs() == "cr") {
 			// lyx can't handle \\cr
diff --git a/status.23x b/status.23x
index 03bc8da..f28c289 100644
--- a/status.23x
+++ b/status.23x
@@ -54,8 +54,6 @@ What's new
 
 
 
-
-
 * DOCUMENTATION AND LOCALIZATION
 
 
@@ -66,7 +64,7 @@ What's new
 
 * TEX2LYX
 
-
+- Fix import of umlauts and ß in math (bug 12739).
 
 
 * LYXHTML
@@ -82,3 +80,4 @@ What's new
 * BUILD/INSTALLATION
 
 - update included boost library to version 1.75.0.
+