Add IsAutoNestedBy

This is complementary to AutoNests: Styles can determine which other
style should auto-nest them. This is particularly useful for modules
that add new styles which should be auto-nested in a given context.

lib/doc/Customization.lyx

@@ -12163,7 +12163,7 @@ Argument item:1
 \end_deeper
 \begin_layout Description
 
-\change_inserted -712698321 1514534780
+\change_inserted -712698321 1514539256
 \begin_inset Flex Code
 status collapsed
 
@@ -12177,7 +12177,8 @@ AutoNests
 
  Includes a comma-separated list of layout names that should be nested in
  and after the current one.
- Only makes sense for nestable layouts (such as environments) 
+ Only makes sense for nestable layouts (such as environments).
+ Must be ended by 
 \begin_inset Quotes eld
 \end_inset
 
@@ -12197,6 +12198,21 @@ EndAutoNests
 \begin_inset Quotes erd
 \end_inset
 
+.
+ See also 
+\begin_inset Flex Code
+status collapsed
+
+\begin_layout Plain Layout
+
+\change_inserted -712698321 1514539161
+IsAutoNestedBy
+\change_unchanged
+
+\end_layout
+
+\end_inset
+
 .
 \end_layout
 
@@ -12929,6 +12945,63 @@ TitleLatexName
 \end_inset
 
  global entries).
+\change_inserted -712698321 1514539171
+
+\end_layout
+
+\begin_layout Description
+
+\change_inserted -712698321 1514539282
+\begin_inset Flex Code
+status collapsed
+
+\begin_layout Plain Layout
+
+\change_inserted -712698321 1514539190
+IsAutoNestedBy
+\end_layout
+
+\end_inset
+
+ Includes a comma-separated list of layout names after which this one should
+ be nested.
+ Only makes sense with regard to nestable layouts (such as environments).
+ Must be ended by 
+\begin_inset Quotes eld
+\end_inset
+
+
+\begin_inset Flex Code
+status collapsed
+
+\begin_layout Plain Layout
+
+\change_inserted -712698321 1514539279
+EndIsAutoNestedBy
+\end_layout
+
+\end_inset
+
+
+\begin_inset Quotes erd
+\end_inset
+
+.
+ See also 
+\begin_inset Flex Code
+status collapsed
+
+\begin_layout Plain Layout
+
+\change_inserted -712698321 1514539172
+AutoNest
+\end_layout
+
+\end_inset
+
+.
+\change_unchanged
+
 \end_layout
 
 \begin_layout Description

lib/scripts/layout2layout.py

@@ -221,7 +221,8 @@ currentFormat = 66
 # Color collapsable -> collapsible
 
 # Incremented to format 66, 28 December 2017 by spitz
-# New Layout tag "AutoNests ... EndAutoNests"
+# New Layout tags "AutoNests ... EndAutoNests" and
+# "IsAutoNestedBy ... EndIsAutoNestedBy"
 
 # Do not forget to document format change in Customization
 # Manual (section "Declaring a new text class").

src/Layout.cpp

@@ -41,6 +41,7 @@ enum LayoutTags {
 	LT_ALIGNPOSSIBLE,
 	LT_ARGUMENT,
 	LT_AUTONESTS,
+	LT_AUTONESTEDBY,
 	LT_MARGIN,
 	LT_BOTTOMSEP,
 	LT_CATEGORY,
@@ -219,6 +220,7 @@ bool Layout::readIgnoreForcelocal(Lexer & lex, TextClass const & tclass)
 		{ "innertag",       LT_INNERTAG },
 		{ "inpreamble",     LT_INPREAMBLE },
 		{ "intitle",        LT_INTITLE },
+		{ "isautonestedby", LT_AUTONESTEDBY },
 		{ "istoccaption",   LT_ISTOCCAPTION },
 		{ "itemcommand",    LT_ITEMCOMMAND },
 		{ "itemsep",        LT_ITEMSEP },
@@ -606,6 +608,18 @@ bool Layout::readIgnoreForcelocal(Lexer & lex, TextClass const & tclass)
 			break;
 		}
 
+		case LT_AUTONESTEDBY: {
+			docstring const autonest =
+				subst(subst(subst(lex.getLongString(from_ascii("EndIsAutoNestedBy")),
+						  from_ascii("\n"), docstring()),
+					    from_ascii(" "), docstring()),
+				      from_ascii("\t"), docstring());
+			vector<docstring> const autonests =
+				getVectorFromString(autonest);
+			autonested_by_.insert(autonests.begin(), autonests.end());
+			break;
+		}
+
 		case LT_REFPREFIX: {
 			docstring arg;
 			lex >> arg;
@@ -1411,6 +1425,16 @@ void Layout::write(ostream & os) const
 		}
 		os << "\n\tEndAutoNests\n";
 	}
+	if (!autonested_by_.empty()) {
+		os << "\tIsAutoNestedBy\n\t";
+		for (set<docstring>::const_iterator it = autonested_by_.begin();
+		     it != autonested_by_.end(); ++it) {
+			if (it != autonested_by_.begin())
+				os << ',';
+			os << to_utf8(*it);
+		}
+		os << "\n\tIsAutoNestedBy\n";
+	}
 	if (refprefix.empty())
 		os << "\tRefPrefix OFF\n";
 	else

src/Layout.h

@@ -151,6 +151,8 @@ public:
 	///
 	std::set<docstring> const & autonests() const { return autonests_; }
 	///
+	std::set<docstring> const & isAutonestedBy() const { return autonested_by_; }
+	///
 	std::string const & latexparam() const { return latexparam_; }
 	///
 	docstring leftdelim() const { return leftdelim_; }
@@ -472,6 +474,8 @@ private:
 	std::set<std::string> requires_;
 	/// Layouts that are by default nested after this one
 	std::set<docstring> autonests_;
+	/// Layouts that by auto-nest this one
+	std::set<docstring> autonested_by_;
 	///
 	LaTeXArgMap latexargs_;
 	///

src/Text3.cpp

@@ -1478,11 +1478,14 @@ void Text::dispatch(Cursor & cur, FuncRequest & cmd)
 			setLayout(cur, layout);
 			bool do_nest = false;
 			set<docstring> autonests;
+			set<docstring> autonested;
 			if (cur.pit() > 0) {
 				autonests = pars_[cur.pit() - 1].layout().autonests();
+				autonested = pars_[cur.pit()].layout().isAutonestedBy();
 				do_nest = !ignoreautonests;
 			}
-			if (do_nest && autonests.find(layout) != autonests.end())
+			if (do_nest && (autonests.find(layout) != autonests.end()
+					|| autonested.find(old_layout) != autonested.end()))
 				lyx::dispatch(FuncRequest(LFUN_DEPTH_INCREMENT));
 		}