Fix bug #8464: stackrel with subscript.

The fix is basically mechanical, the additional code for fraction like insets
with three arguments was stolen from \unitfrac. As any math package,
stackrel.sty needs a buffer parameter to switch it off.
I also added the two stackrel flavours to the toolbar.

development/FORMAT

@@ -11,6 +11,11 @@ adjustments are made to tex2lyx and bugs are fixed in lyx2lyx.
 
 -----------------------
 
+2012-12-28 Georg Baum  <Georg.Baum@post.rwth-aachen.de>
+	* Format incremented to 457
+	  support for the LaTeX-package stackrel (fix bug 8464)
+	  New buffer param \use_package stackrel
+
 2012-12-28 Jürgen Spitzmüller <spitz@lyx.org>
 	* Format incremented to 456: Proper support for memoir \epigraph
 	  \epigraph{text}{source} > begin_layout Epigraph, <source> as

lib/Makefile.am

@@ -978,6 +978,8 @@ dist_imagesmath_DATA = \
 	images/math/ssearrow.png \
 	images/math/sslash.png \
 	images/math/sswarrow.png \
+	images/math/stackrel.png \
+	images/math/stackrelthree.png \
 	images/math/star.png \
 	images/math/style.png \
 	images/math/sub.png \

lib/chkconfig.ltx

@@ -343,6 +343,7 @@
 \TestPackage{slashed}
 \TestPackage{soul}
 \TestPackage{splitidx}
+\TestPackage{stackrel}
 \TestPackage{stmaryrd}
 \TestPackage{subfig}
 \TestPackage{Sweave}

lib/doc/LaTeXConfig.lyx

@@ -6580,6 +6580,36 @@ splitindex
  converter programs.
 \end_layout
 
+\begin_layout Subsection
+stackrel
+\end_layout
+
+\begin_layout Description
+Found: 
+\begin_inset Info
+type  "package"
+arg   "stackrel"
+\end_inset
+
+
+\end_layout
+
+\begin_layout Description
+CTAN: 
+\family typewriter
+macros/latex/contrib/oberdiek
+\end_layout
+
+\begin_layout Description
+Notes: The package 
+\family sans
+stackrel
+\family default
+ is needed by LyX to be able to output formulas using the 
+\backslash
+stackrel command with subscript.
+\end_layout
+
 \begin_layout Subsection
 stmaryrd
 \end_layout

lib/lyx2lyx/lyx_2_1.py

@@ -495,6 +495,49 @@ def revert_use_stmaryrd(document):
             i = j
 
 
+def convert_use_stackrel(document):
+    "insert use_package stackrel"
+    i = find_token(document.header, "\\use_package", 0)
+    if i == -1:
+        document.warning("Malformed LyX document: Can't find \\use_package.")
+        return;
+    j = find_token(document.preamble, "\\usepackage{stackrel}", 0)
+    if j == -1:
+        document.header.insert(i + 1, "\\use_package stackrel 0")
+    else:
+        document.header.insert(i + 1, "\\use_package stackrel 2")
+        del document.preamble[j]
+
+
+def revert_use_stackrel(document):
+    "remove use_package stackrel"
+    regexp = re.compile(r'(\\use_package\s+stackrel)')
+    i = find_re(document.header, regexp, 0)
+    value = "1" # default is auto
+    if i != -1:
+        value = get_value(document.header, "\\use_package" , i).split()[1]
+        del document.header[i]
+    if value == "2": # on
+        add_to_preamble(document, ["\\usepackage{stackrel}"])
+    elif value == "1": # auto
+        regcmd = re.compile(r'.*\\stackrel\s*\[')
+        i = 0
+        while True:
+            i = find_token(document.body, '\\begin_inset Formula', i)
+            if i == -1:
+                return
+            j = find_end_of_inset(document.body, i)
+            if j == -1:
+                document.warning("Malformed LyX document: Can't find end of Formula inset at line " + str(i))
+                i += 1
+                continue
+            code = "\n".join(document.body[i:j])
+            if regcmd.match(code):
+                add_to_preamble(document, ["\\usepackage{stackrel}"])
+                return
+            i = j
+
+
 def convert_cite_engine_type(document):
     "Determine the \\cite_engine_type from the citation engine."
     i = find_token(document.header, "\\cite_engine", 0)
@@ -3022,10 +3065,12 @@ convert = [
            [453, [convert_use_stmaryrd]],
            [454, [convert_overprint]],
            [455, []],
-           [456, [convert_epigraph]]
+           [456, [convert_epigraph]],
+           [457, [convert_use_stackrel]]
           ]
 
 revert =  [
+           [456, [revert_use_stackrel]],
            [455, [revert_epigraph]],
            [454, [revert_frametitle]],
            [453, [revert_overprint]],

lib/ui/stdtoolbars.inc

@@ -435,6 +435,8 @@ ToolbarSet
 		Item "bcancel" "math-insert \bcancel"
 		Item "xcancel" "math-insert \xcancel"
 		Item "cancelto" "math-insert \cancelto"
+		Item "stackrel" "math-insert \stackrel"
+		Item "stackrelthree" "math-insert \stackrelthree"
 	End
 
 	Toolbar "latex_arrow" "Arrows"

src/BufferParams.cpp

@@ -454,6 +454,7 @@ vector<string> const & BufferParams::auto_packages()
 		packages.push_back("mathdots");
 		packages.push_back("mathtools");
 		packages.push_back("mhchem");
+		packages.push_back("stackrel");
 		packages.push_back("stmaryrd");
 		packages.push_back("undertilde");
 	}

src/BufferParams.h

@@ -519,7 +519,7 @@ private:
 
 	typedef std::map<std::string, Package> PackageMap;
 	/** Whether and how to load packages like amsmath, esint, mhchem,
-	 *  mathdots and undertilde.
+	 *  mathdots, stackrel, stmaryrd and undertilde.
 	 */
 	PackageMap use_packages;
 

src/LaTeXFeatures.cpp

@@ -851,6 +851,10 @@ string const LaTeXFeatures::getPackages() const
 	    params_.use_package("stmaryrd") != BufferParams::package_off)
 		packages << "\\usepackage{stmaryrd}\n";
 
+	if (mustProvide("stackrel") &&
+	    params_.use_package("stackrel") != BufferParams::package_off)
+		packages << "\\usepackage{stackrel}\n";
+
 	if (mustProvide("undertilde") &&
 		params_.use_package("undertilde") != BufferParams::package_off)
 		packages << "\\usepackage{undertilde}\n";

src/frontends/qt4/GuiDocument.cpp

@@ -156,6 +156,10 @@ char const * packages_gui[][4] =
 	 N_("Use mhchem &package automatically"),
 	 N_("Use mh&chem package"),
 	 N_("The LaTeX package mhchem is only used if either the command \\ce or \\cf is inserted into formulas")},
+	{"stackrel",
+	 N_("Use stackrel package automatically"),
+	 N_("Use stackrel package"),
+	 N_("The LaTeX package stackrel is only used if the command \\stackrel with subscript is inserted into formulas")},
 	{"stmaryrd",
 	 N_("Use stmaryrd package automatically"),
 	 N_("Use stmaryrd package"),

src/mathed/InsetMathNest.cpp

@@ -2099,6 +2099,7 @@ MathCompletionList::MathCompletionList(Cursor const & cur)
 	globals.push_back(from_ascii("\\root"));
 	globals.push_back(from_ascii("\\tabular"));
 	globals.push_back(from_ascii("\\stackrel"));
+	globals.push_back(from_ascii("\\stackrelthree"));
 	globals.push_back(from_ascii("\\binom"));
 	globals.push_back(from_ascii("\\choose"));
 	globals.push_back(from_ascii("\\brace"));

src/mathed/InsetMathStackrel.cpp

@@ -12,6 +12,7 @@
 
 #include "InsetMathStackrel.h"
 
+#include "Cursor.h"
 #include "LaTeXFeatures.h"
 #include "MathData.h"
 #include "MathStream.h"
@@ -20,7 +21,8 @@ using namespace std;
 
 namespace lyx {
 
-InsetMathStackrel::InsetMathStackrel(Buffer * buf) : InsetMathFracBase(buf)
+InsetMathStackrel::InsetMathStackrel(Buffer * buf, bool sub)
+	: InsetMathFracBase(buf, sub ? 3 : 2)
 {}
 
 
@@ -30,6 +32,24 @@ Inset * InsetMathStackrel::clone() const
 }
 
 
+bool InsetMathStackrel::idxUpDown(Cursor & cur, bool up) const
+{
+	if (up) {
+		if (cur.idx() == 0)
+			return false;
+	} else {
+		if (cur.idx() + 1 ==  nargs())
+			return false;
+	}
+	InsetMath::idx_type target = up ? cur.idx() - 1 : cur.idx() + 1;
+	if (cur.idx() == target)
+		return false;
+	cur.idx() = target;
+	cur.pos() = cell(target).x2pos(&cur.bv(), cur.x_target());
+	return true;
+}
+
+
 void InsetMathStackrel::metrics(MetricsInfo & mi, Dimension & dim) const
 {
 	Dimension dim1;
@@ -37,9 +57,17 @@ void InsetMathStackrel::metrics(MetricsInfo & mi, Dimension & dim) const
 	FracChanger dummy(mi.base);
 	Dimension dim0;
 	cell(0).metrics(mi, dim0);
-	dim.wid = max(dim0.width(), dim1.width()) + 4;
-	dim.asc = dim1.ascent() + dim0.height() + 4;
-	dim.des = dim1.descent();
+	if (nargs() > 2) {
+		Dimension dim2;
+		cell(2).metrics(mi, dim2);
+		dim.wid = max(max(dim0.width(), dim1.width()), dim2.width()) + 4;
+		dim.asc = dim1.ascent() + dim0.height() + 4;
+		dim.des = dim1.descent() + dim2.height() + dim2.descent() + 1;
+	} else {
+		dim.wid = max(dim0.width(), dim1.width()) + 4;
+		dim.asc = dim1.ascent() + dim0.height() + 4;
+		dim.des = dim1.descent();
+	}
 	metricsMarkers(dim);
 }
 
@@ -54,6 +82,11 @@ void InsetMathStackrel::draw(PainterInfo & pi, int x, int y) const
 	cell(1).draw(pi, m - dim1.width() / 2, y);
 	FracChanger dummy(pi.base);
 	cell(0).draw(pi, m - dim0.width() / 2, yo);
+	if (nargs() > 2) {
+		Dimension const & dim2 = cell(2).dimension(*pi.base.bv);
+		int y2 = y + dim1.descent() + dim2.ascent() + 1;
+		cell(2).draw(pi, m - dim2.width() / 2, y2);
+	}
 	drawMarkers(pi, x, y);
 }
 
@@ -61,40 +94,69 @@ void InsetMathStackrel::draw(PainterInfo & pi, int x, int y) const
 void InsetMathStackrel::write(WriteStream & os) const
 {
 	MathEnsurer ensurer(os);
-	os << "\\stackrel{" << cell(0) << "}{" << cell(1) << '}';
+	os << "\\stackrel";
+	if (nargs() > 2)
+		os << '[' << cell(2) << ']';
+	os << '{' << cell(0) << "}{" << cell(1) << '}';
 }
 
 
 void InsetMathStackrel::normalize(NormalStream & os) const
 {
-	os << "[stackrel " << cell(0) << ' ' << cell(1) << ']';
+	os << "[stackrel " << cell(0) << ' ' << cell(1);
+	if (nargs() > 2)
+		os << ' ' << cell(2);
+	os << ']';
 }
 
 
 void InsetMathStackrel::mathmlize(MathStream & ms) const
 {
-	ms << "<mover accent='false'>" << cell(1) << cell(0) << "</mover>";
+	if (nargs() > 2)
+		ms << "<munderover>" << cell(1) << cell(2) << cell(0) << "</munderover>";
+	else
+		ms << "<mover accent='false'>" << cell(1) << cell(0) << "</mover>";
 }
 
 
 void InsetMathStackrel::htmlize(HtmlStream & os) const
 {
-	// at the moment, this is exactly the same as overset
-	os << MTag("span", "class='overset'")
-		 << MTag("span", "class='top'") << cell(0) << ETag("span")
-		 << MTag("span") << cell(1) << ETag("span")
-		 << ETag("span");
+	if (nargs() > 2) {
+		os << MTag("span", "class='underoverset'")
+		   << MTag("span", "class='top'") << cell(0) << ETag("span")
+		   << MTag("span") << cell(1) << ETag("span")
+		   << MTag("span", "class='bottom'") << cell(2) << ETag("span");
+	} else {
+		// at the moment, this is exactly the same as overset
+		os << MTag("span", "class='overset'")
+		   << MTag("span", "class='top'") << cell(0) << ETag("span")
+		   << MTag("span") << cell(1) << ETag("span");
+	}
+	os << ETag("span");
 }
 
 
 void InsetMathStackrel::validate(LaTeXFeatures & features) const
 {
-	// from overset
-	if (features.runparams().math_flavor == OutputParams::MathAsHTML)
-		features.addCSSSnippet(
-			"span.overset{display: inline-block; vertical-align: bottom; text-align:center;}\n"
-			"span.overset span {display: block;}\n"
-			"span.top{font-size: 66%;}");
+	if (features.runparams().math_flavor == OutputParams::MathAsHTML) {
+		if (nargs() > 2) {
+			// FIXME: "vertical-align: middle" works only if the
+			// height of sub and super script is approximately equal.
+			features.addCSSSnippet(
+				"span.underoverset{display: inline-block; vertical-align: middle; text-align:center;}\n"
+				"span.underoverset span {display: block;}\n"
+				"span.bottom{font-size: 66%;}\n"
+				"span.top{font-size: 66%;}");
+		} else {
+			// from overset
+			features.addCSSSnippet(
+				"span.overset{display: inline-block; vertical-align: bottom; text-align:center;}\n"
+				"span.overset span {display: block;}\n"
+				"span.top{font-size: 66%;}");
+		}
+	}
+	if (nargs() > 2)
+		features.require("stackrel");
 
 	InsetMathNest::validate(features);
 }

src/mathed/InsetMathStackrel.h

@@ -20,7 +20,9 @@ namespace lyx {
 class InsetMathStackrel : public InsetMathFracBase {
 public:
 	///
-	InsetMathStackrel(Buffer * buf);
+	InsetMathStackrel(Buffer * buf, bool sub);
+	///
+	bool idxUpDown(Cursor &, bool up) const;
 	///
 	void metrics(MetricsInfo & mi, Dimension & dim) const;
 	///

src/mathed/MathFactory.cpp

@@ -453,7 +453,10 @@ MathAtom createInsetMath(docstring const & s, Buffer * buf)
 	if (s == "tabular")
 		return MathAtom(new InsetMathTabular(buf, s, 1, 1));
 	if (s == "stackrel")
-		return MathAtom(new InsetMathStackrel(buf));
+		return MathAtom(new InsetMathStackrel(buf, false));
+	// This string value is only for math toolbar use, no LaTeX name
+	if (s == "stackrelthree")
+		return MathAtom(new InsetMathStackrel(buf, true));
 	if (s == "binom")
 		return MathAtom(new InsetMathBinom(buf, InsetMathBinom::BINOM));
 	if (s == "dbinom")

src/mathed/MathParser.cpp

@@ -59,6 +59,7 @@ following hack as starting point to write some macros:
 #include "InsetMathSpace.h"
 #include "InsetMathSplit.h"
 #include "InsetMathSqrt.h"
+#include "InsetMathStackrel.h"
 #include "InsetMathString.h"
 #include "InsetMathTabular.h"
 #include "MathMacroTemplate.h"
@@ -1441,6 +1442,17 @@ bool Parser::parse1(InsetMathGrid & grid, unsigned flags,
 			parse(cell->back().nucleus()->cell(1), FLAG_ITEM, mode);
 		}
 
+		else if (t.cs() == "stackrel") {
+			// Here allowed formats are \stackrel[subscript]{superscript}{operator}
+			MathData ar;
+			parse(ar, FLAG_OPTION, mode);
+			cell->push_back(MathAtom(new InsetMathStackrel(buf, !ar.empty())));
+			if (!ar.empty())
+				cell->back().nucleus()->cell(2) = ar;
+			parse(cell->back().nucleus()->cell(0), FLAG_ITEM, mode);
+			parse(cell->back().nucleus()->cell(1), FLAG_ITEM, mode);
+		}
+
 		else if (t.cs() == "xrightarrow" || t.cs() == "xleftarrow") {
 			cell->push_back(createInsetMath(t.cs(), buf));
 			parse(cell->back().nucleus()->cell(1), FLAG_OPTION, mode);

src/tex2lyx/Preamble.cpp

@@ -517,6 +517,7 @@ Preamble::Preamble() : one_language(true), title_layout_found(false)
 	h_use_packages["mhchem"]     = "0";
 	h_use_packages["mathdots"]   = "0";
 	h_use_packages["mathtools"]  = "0";
+	h_use_packages["stackrel"]   = "0";
 	h_use_packages["stmaryrd"]   = "0";
 	h_use_packages["undertilde"] = "0";
 }
@@ -703,8 +704,8 @@ void Preamble::handle_package(Parser &p, string const & name,
 
 	else if (name == "amsmath" || name == "amssymb" ||
 	         name == "esint" || name == "mhchem" || name == "mathdots" ||
-	         name == "mathtools" || name == "stmaryrd" ||
-		 name == "undertilde")
+	         name == "mathtools" || name == "stackrel" ||
+		 name == "stmaryrd" || name == "undertilde")
 		h_use_packages[name] = "2";
 
 	else if (name == "babel") {

src/tex2lyx/TODO.txt

@@ -97,6 +97,7 @@ Format LaTeX feature                        LyX feature
 455    beamer frametitle command            \begin_layout FrameTitle
        \frametitle<overlay>[short}{long}
 456    memoir: \epigraph{text}{source}      layout Epigraph, InsetArgument
+457    automatic stackrel loading           \use_package stackrel
 
 
 General

src/tex2lyx/test/CJK.lyx.lyx

@@ -1,5 +1,5 @@
 #LyX file created by tex2lyx 2.1.0dev
-\lyxformat 456
+\lyxformat 457
 \begin_document
 \begin_header
 \textclass article
@@ -46,6 +46,7 @@
 \use_package mathdots 0
 \use_package mathtools 0
 \use_package mhchem 0
+\use_package stackrel 0
 \use_package stmaryrd 0
 \use_package undertilde 0
 \cite_engine basic

src/tex2lyx/test/DummyDocument.lyx

@@ -1,5 +1,5 @@
 #LyX file created by tex2lyx 2.1.0dev
-\lyxformat 456
+\lyxformat 457
 \begin_document
 \begin_header
 \textclass article
@@ -44,6 +44,7 @@
 \use_package mathdots 0
 \use_package mathtools 0
 \use_package mhchem 0
+\use_package stackrel 0
 \use_package stmaryrd 0
 \use_package undertilde 0
 \cite_engine natbib

src/tex2lyx/test/XeTeX-polyglossia.lyx.lyx

@@ -1,5 +1,5 @@
 #LyX file created by tex2lyx 2.1.0dev
-\lyxformat 456
+\lyxformat 457
 \begin_document
 \begin_header
 \textclass article
@@ -46,6 +46,7 @@
 \use_package mathdots 0
 \use_package mathtools 0
 \use_package mhchem 0
+\use_package stackrel 0
 \use_package stmaryrd 0
 \use_package undertilde 0
 \cite_engine basic

src/tex2lyx/test/box-color-size-space-align.lyx.lyx

@@ -1,5 +1,5 @@
 #LyX file created by tex2lyx 2.1.0dev
-\lyxformat 456
+\lyxformat 457
 \begin_document
 \begin_header
 \textclass article
@@ -70,6 +70,7 @@
 \use_package mathdots 0
 \use_package mathtools 0
 \use_package mhchem 0
+\use_package stackrel 0
 \use_package stmaryrd 0
 \use_package undertilde 0
 \cite_engine basic

src/tex2lyx/test/test-insets.lyx.lyx

@@ -1,5 +1,5 @@
 #LyX file created by tex2lyx 2.1.0dev
-\lyxformat 456
+\lyxformat 457
 \begin_document
 \begin_header
 \textclass article
@@ -50,6 +50,7 @@
 \use_package mathdots 0
 \use_package mathtools 0
 \use_package mhchem 0
+\use_package stackrel 0
 \use_package stmaryrd 0
 \use_package undertilde 0
 \cite_engine natbib

src/tex2lyx/test/test-modules.lyx.lyx

@@ -1,5 +1,5 @@
 #LyX file created by tex2lyx 2.1.0dev
-\lyxformat 456
+\lyxformat 457
 \begin_document
 \begin_header
 \textclass amsart
@@ -42,6 +42,7 @@ theorems-ams
 \use_package mathdots 0
 \use_package mathtools 0
 \use_package mhchem 0
+\use_package stackrel 0
 \use_package stmaryrd 0
 \use_package undertilde 0
 \cite_engine basic

src/tex2lyx/test/test-structure.lyx.lyx

@@ -1,5 +1,5 @@
 #LyX file created by tex2lyx 2.1.0dev
-\lyxformat 456
+\lyxformat 457
 \begin_document
 \begin_header
 \textclass article
@@ -75,6 +75,7 @@ logicalmkup
 \use_package mathdots 0
 \use_package mathtools 0
 \use_package mhchem 0
+\use_package stackrel 0
 \use_package stmaryrd 0
 \use_package undertilde 0
 \cite_engine basic

src/tex2lyx/test/test.lyx.lyx

@@ -1,5 +1,5 @@
 #LyX file created by tex2lyx 2.1.0dev
-\lyxformat 456
+\lyxformat 457
 \begin_document
 \begin_header
 \textclass article
@@ -46,6 +46,7 @@
 \use_package mathdots 0
 \use_package mathtools 0
 \use_package mhchem 0
+\use_package stackrel 0
 \use_package stmaryrd 0
 \use_package undertilde 0
 \cite_engine basic

src/version.h

@@ -30,8 +30,8 @@ extern char const * const lyx_version_info;
 
 // Do not remove the comment below, so we get merge conflict in
 // independent branches. Instead add your own.
-#define LYX_FORMAT_LYX 456 // spitz: proper support for memoir epigraph
-#define LYX_FORMAT_TEX2LYX 456 // spitz: proper support for memoir epigraph
+#define LYX_FORMAT_LYX 457 // gb: automatic stackrel package loading
+#define LYX_FORMAT_TEX2LYX 457 // gb: automatic stackrel package loading
 
 #if LYX_FORMAT_TEX2LYX != LYX_FORMAT_LYX
 #ifndef _MSC_VER