From: Jean-Marc Lasgouttes <lasgouttes@lyx.org>
Date: Mon, 3 Sep 2018 15:49:54 +0000 (+0200)
Subject: Allow toggling (no)limits only after mathop symbol
X-Git-Tag: 2.3.3~59
X-Git-Url: https://git.lyx.org/gitweb/?a=commitdiff_plain;h=85e693806e206b24e9fd7d010368fba36a2b9710;p=features.git

Allow toggling (no)limits only after mathop symbol

In particular, introduce the new InsetMathScript::allowLimits method
that checks for that and honor it in getStatus/ddoDispatch.

Do the same for (over|under)brace

(cherry picked from commit 7b7ed64a0e760eccad5fff7fa944b983d0bed025)
(cherry picked from commit 6cfd733dea70bf26c512dea8491f79f68cb512e6)
---

diff --git a/src/mathed/InsetMathDecoration.cpp b/src/mathed/InsetMathDecoration.cpp
index 908a887eeb..1262370953 100644
--- a/src/mathed/InsetMathDecoration.cpp
+++ b/src/mathed/InsetMathDecoration.cpp
@@ -55,11 +55,17 @@ bool InsetMathDecoration::upper() const
 }
 
 
+MathClass InsetMathDecoration::mathClass() const
+{
+	if (key_->name == "overbrace" || key_->name == "underbrace")
+		return MC_OP;
+	return MC_ORD;
+}
+
+
 bool InsetMathDecoration::isScriptable() const
 {
-	return
-			key_->name == "overbrace" ||
-			key_->name == "underbrace";
+	return mathClass() == MC_OP;
 }
 
 
diff --git a/src/mathed/InsetMathDecoration.h b/src/mathed/InsetMathDecoration.h
index 9e58065ee3..a5d5e9c9b8 100644
--- a/src/mathed/InsetMathDecoration.h
+++ b/src/mathed/InsetMathDecoration.h
@@ -38,6 +38,8 @@ public:
 	///
 	void infoize(odocstream & os) const;
 	///
+	MathClass mathClass() const;
+	///
 	bool isScriptable() const;
 	///
 	void validate(LaTeXFeatures & features) const;
diff --git a/src/mathed/InsetMathScript.cpp b/src/mathed/InsetMathScript.cpp
index 57f3b87f88..315637c2da 100644
--- a/src/mathed/InsetMathScript.cpp
+++ b/src/mathed/InsetMathScript.cpp
@@ -381,6 +381,20 @@ void InsetMathScript::drawT(TextPainter & pain, int x, int y) const
 }
 
 
+// FIXME: See InsetMathSymbol::takesLimits, which seems to attempt the
+// same in a hardcoded way. takeLimits use is currently commented out in
+// InsetMathScript::metrics. It seems that the mathop test is general
+// enough, but only time will tell.
+bool InsetMathScript::allowsLimits() const
+{
+	if (nuc().empty())
+		return false;
+	// Only makes sense for insets of mathop class
+	if (nuc().back()->mathClass() != MC_OP)
+		return false;
+	return true;
+}
+
 
 bool InsetMathScript::hasLimits() const
 {
@@ -391,8 +405,9 @@ bool InsetMathScript::hasLimits() const
 		return false;
 
 	// we can only display limits if the nucleus wants some
-	if (nuc().empty())
+	if (!allowsLimits())
 		return false;
+	// FIXME: this is some hardcoding done in InsetMathSymbol::metrics.
 	if (!nuc().back()->isScriptable())
 		return false;
 
@@ -751,6 +766,9 @@ void InsetMathScript::doDispatch(Cursor & cur, FuncRequest & cmd)
 	//LYXERR("InsetMathScript: request: " << cmd);
 
 	if (cmd.action() == LFUN_MATH_LIMITS) {
+		// only when nucleus allows this
+		if (!allowsLimits())
+			return;
 		cur.recordUndoInset();
 		if (!cmd.argument().empty()) {
 			if (cmd.argument() == "limits")
@@ -774,15 +792,19 @@ bool InsetMathScript::getStatus(Cursor & cur, FuncRequest const & cmd,
 				FuncStatus & flag) const
 {
 	if (cmd.action() == LFUN_MATH_LIMITS) {
-		if (!cmd.argument().empty()) {
-			if (cmd.argument() == "limits")
-				flag.setOnOff(limits_ == 1);
-			else if (cmd.argument() == "nolimits")
-				flag.setOnOff(limits_ == -1);
-			else
-				flag.setOnOff(limits_ == 0);
-		}
-		flag.setEnabled(true);
+		// only when nucleus allows this
+		if (allowsLimits()) {
+			if (!cmd.argument().empty()) {
+				if (cmd.argument() == "limits")
+					flag.setOnOff(limits_ == 1);
+				else if (cmd.argument() == "nolimits")
+					flag.setOnOff(limits_ == -1);
+				else
+					flag.setOnOff(limits_ == 0);
+			}
+			flag.setEnabled(true);
+		} else
+			flag.setEnabled(false);
 		return true;
 	}
 
diff --git a/src/mathed/InsetMathScript.h b/src/mathed/InsetMathScript.h
index 0b96d03ce2..51c8a2f710 100644
--- a/src/mathed/InsetMathScript.h
+++ b/src/mathed/InsetMathScript.h
@@ -140,6 +140,8 @@ private:
 	/// shifts the superscript to the right, and a negative value shifts the
 	/// subscript to the left.
 	int nker(BufferView const * bv) const;
+	/// can one change how scripts are drawn?
+	bool allowsLimits() const;
 	/// where do we have to draw the scripts?
 	bool hasLimits() const;
 	/// clean up empty cells and return true if a cell has been deleted.
diff --git a/status.23x b/status.23x
index 07e2adcb04..c35e9577c7 100644
--- a/status.23x
+++ b/status.23x
@@ -121,6 +121,8 @@ What's new
 
 - Fix crash when using inset-select-all in tabular.
 
+- Only allow toggling math limits when it makes sense.
+
 
 * INTERNALS