From 858b076ab7aed3f41e7ad97f1a3a2fbf0589d7bf Mon Sep 17 00:00:00 2001
From: Juergen Spitzmueller <spitz@lyx.org>
Date: Fri, 11 Aug 2023 17:35:18 +0200
Subject: [PATCH] Work around French babel's incompatibility with prettyref

In classic (pdf)latex, where the colon is activated, detokenize
the argument of \prettyref.

Fix proposed by egreg at
https://tex.stackexchange.com/a/527912/19291
---
 lib/languages         | 2 ++
 src/LaTeXFeatures.cpp | 8 ++++++++
 2 files changed, 10 insertions(+)

diff --git a/lib/languages b/lib/languages
index 58c85ccfb4..3101ee3990 100644
--- a/lib/languages
+++ b/lib/languages
@@ -498,6 +498,7 @@ Language canadien
 	BabelName        acadian
 	PolyglossiaName  french
 	PolyglossiaOpts  "variant=canadian"
+	ActiveChars      ;!?:
 	XindyName        french
 	QuoteStyle       french
 	Encoding         iso8859-15
@@ -705,6 +706,7 @@ Language french
 	GuiName          "French"
 	HasGuiSupport    true
 	BabelName        french
+	ActiveChars      ;!?:
 	PolyglossiaName  french
 	XindyName        french
 	QuoteStyle       french
diff --git a/src/LaTeXFeatures.cpp b/src/LaTeXFeatures.cpp
index 364a4921e1..0e678ea62a 100644
--- a/src/LaTeXFeatures.cpp
+++ b/src/LaTeXFeatures.cpp
@@ -1284,6 +1284,14 @@ string const LaTeXFeatures::getPackages() const
 	// The rest of these packages are somewhat more complicated
 	// than those above.
 
+	// Babel languages with activated colon (such as French) break
+	// with prettyref. Work around that.
+	if (!runparams_.isFullUnicode() && useBabel()
+	    && mustProvide("prettyref") && contains(getActiveChars(), ':')) {
+		packages << "% Make prettyref compatible with babel active colon\n"
+			 << "\\def\\prettyref#1{\\expandafter\\@prettyref\\detokenize{#1:}}\n";
+	}
+
 	if (mustProvide("changebar")) {
 		packages << "\\usepackage";
 		if (runparams_.flavor == Flavor::LaTeX