ctests: add a test file for #12708

The file is taken from #12727 which is a duplicate.

autotests/export/latex/lyxbugs/12708-refstyle-amsmath.lyx

@@ -0,0 +1,123 @@
+#LyX 2.3 created this file. For more info see http://www.lyx.org/
+\lyxformat 544
+\begin_document
+\begin_header
+\save_transient_properties true
+\origin unavailable
+\textclass article
+\use_default_options true
+\begin_modules
+theorems-ams
+\end_modules
+\maintain_unincluded_children false
+\language english
+\language_package default
+\inputencoding auto
+\fontencoding global
+\font_roman "default" "default"
+\font_sans "default" "default"
+\font_typewriter "default" "default"
+\font_math "libertine-ntxm" "auto"
+\font_default_family default
+\use_non_tex_fonts false
+\font_sc false
+\font_osf false
+\font_sf_scale 100 100
+\font_tt_scale 100 100
+\use_microtype false
+\use_dash_ligatures true
+\graphics default
+\default_output_format default
+\output_sync 1
+\bibtex_command default
+\index_command default
+\paperfontsize default
+\spacing single
+\use_hyperref true
+\pdf_bookmarks true
+\pdf_bookmarksnumbered false
+\pdf_bookmarksopen false
+\pdf_bookmarksopenlevel 1
+\pdf_breaklinks true
+\pdf_pdfborder true
+\pdf_colorlinks true
+\pdf_backref false
+\pdf_pdfusetitle true
+\pdf_quoted_options "allcolors=blue"
+\papersize default
+\use_geometry true
+\use_package amsmath 1
+\use_package amssymb 1
+\use_package cancel 1
+\use_package esint 1
+\use_package mathdots 1
+\use_package mathtools 1
+\use_package mhchem 1
+\use_package stackrel 1
+\use_package stmaryrd 1
+\use_package undertilde 1
+\cite_engine basic
+\cite_engine_type default
+\biblio_style plain
+\use_bibtopic false
+\use_indices false
+\paperorientation portrait
+\suppress_date false
+\justification true
+\use_refstyle 1
+\use_minted 0
+\index Index
+\shortcut idx
+\color #008000
+\end_index
+\leftmargin 1.5in
+\topmargin 1in
+\rightmargin 1.5in
+\bottommargin 1in
+\secnumdepth 3
+\tocdepth 3
+\paragraph_separation indent
+\paragraph_indentation default
+\is_math_indent 0
+\math_numbering_side default
+\quotes_style english
+\dynamic_quotes 0
+\papercolumns 1
+\papersides 1
+\paperpagestyle default
+\tracking_changes false
+\output_changes false
+\html_math_output 0
+\html_css_as_file 0
+\html_be_strict false
+\end_header
+
+\begin_body
+
+\begin_layout Standard
+\begin_inset Formula 
+\begin{align}
+x & =2\label{eq:x}\\
+y & =3\label{eq:y}
+\end{align}
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+\begin_inset CommandInset ref
+LatexCommand formatted
+reference "eq:x"
+plural "false"
+caps "false"
+noprefix "false"
+
+\end_inset
+
+
+\end_layout
+
+\end_body
+\end_document

development/autotests/invertedTests

@@ -87,6 +87,7 @@ export/export/latex/languages/nested-inputenc_auto-legacy_pdf2
 
 # - This test is usually inverted, but it works with the DocBook backend.
 !export/export/latex/lyxbugs/3059-language-in-tables_docbook5
+!export/export/latex/lyxbugs/12708-refstyle-amsmath_docbook5
 
 # ================================================
 Sublabel: lyxbugs