Make end-of-line a valid breakpoint (so it might override earlier poor breakpoint). See #1970.

Author: dpvc

unpacked/jax/output/CommonHTML/autoload/multiline.js

@@ -29,7 +29,11 @@ MathJax.Hub.Register.StartupHook("CommonHTML Jax Ready",function () {
   var MML = MathJax.ElementJax.mml,
       CONFIG = MathJax.Hub.config,
       CHTML = MathJax.OutputJax.CommonHTML;
-      
+  //
+  //  Fake node used for testing end-of-line potential breakpoint
+  //
+  var MO = MML.mo().With({CHTML: CHTML.BBOX.empty()});
+  
   //
   //  Penalties for the various line breaks
   //
@@ -110,7 +114,7 @@ MathJax.Hub.Register.StartupHook("CommonHTML Jax Ready",function () {
           },
           broken = false;
 
-      while (this.CHTMLbetterBreak(end,state) && 
+      while (this.CHTMLbetterBreak(end,state,true) && 
              (end.scanW >= CHTML.linebreakWidth || end.penalty === PENALTY.newline)) {
         this.CHTMLaddLine(stack,start,end.index,state,end.values,broken);
         start = end.index.slice(0); broken = true;
@@ -133,7 +137,7 @@ MathJax.Hub.Register.StartupHook("CommonHTML Jax Ready",function () {
     //
     //  Locate the next linebreak that is better than the current one
     //
-    CHTMLbetterBreak: function (info,state) {
+    CHTMLbetterBreak: function (info,state,toplevel) {
       if (this.isToken) return false;  // FIXME: handle breaking of token elements
       if (this.isEmbellished()) {
         info.embellished = this;
@@ -165,6 +169,13 @@ MathJax.Hub.Register.StartupHook("CommonHTML Jax Ready",function () {
         }
         info.index = []; i++; broken = false;
       }
+      //
+      //  Check if end-of-line is a better breakpoint
+      //
+      if (toplevel && better) {
+        MO.parent = this.parent; MO.inherit = this.inherit;
+        if (MO.CHTMLbetterBreak(info,state)) {better = false; index = info.index}
+      }
       if (info.nest) {info.nest--}
       info.index = index;
       if (better) {info.W = W; info.w = w}

unpacked/jax/output/HTML-CSS/autoload/multiline.js

@@ -28,6 +28,10 @@ MathJax.Hub.Register.StartupHook("HTML-CSS Jax Ready",function () {
   var VERSION = "2.7.4";
   var MML = MathJax.ElementJax.mml,
       HTMLCSS = MathJax.OutputJax["HTML-CSS"];
+  //
+  //  Fake node used for testing end-of-line potential breakpoint
+  //
+  var MO = MML.mo().With({HTMLspanElement: function () {return {bbox: {w:0}, style: {}}}});
 
   //
   //  Penalties for the various line breaks
@@ -109,7 +113,7 @@ MathJax.Hub.Register.StartupHook("HTML-CSS Jax Ready",function () {
           },
           broken = false;
 
-      while (this.HTMLbetterBreak(end,state) && 
+      while (this.HTMLbetterBreak(end,state,true) && 
              (end.scanW >= HTMLCSS.linebreakWidth || end.penalty === PENALTY.newline)) {
         this.HTMLaddLine(stack,start,end.index,state,end.values,broken);
         start = end.index.slice(0); broken = true;
@@ -140,7 +144,7 @@ MathJax.Hub.Register.StartupHook("HTML-CSS Jax Ready",function () {
     //
     //  Locate the next linebreak that is better than the current one
     //
-    HTMLbetterBreak: function (info,state) {
+    HTMLbetterBreak: function (info,state,toplevel) {
       if (this.isToken) {return false}  // FIXME: handle breaking of token elements
       if (this.isEmbellished()) {
         info.embellished = this;
@@ -172,6 +176,13 @@ MathJax.Hub.Register.StartupHook("HTML-CSS Jax Ready",function () {
         }
         info.index = []; i++; broken = false;
       }
+      //
+      //  Check if end-of-line is a better breakpoint
+      //
+      if (toplevel && better) {
+        MO.parent = this.parent; MO.inherit = this.inherit;
+        if (MO.HTMLbetterBreak(info,state)) {better = false; index = info.index}
+      }
       if (info.nest) {info.nest--}
       info.index = index;
       if (better) {info.W = W; info.w = w}

unpacked/jax/output/SVG/autoload/multiline.js

@@ -29,7 +29,11 @@ MathJax.Hub.Register.StartupHook("SVG Jax Ready",function () {
   var MML = MathJax.ElementJax.mml,
       SVG = MathJax.OutputJax.SVG,
       BBOX = SVG.BBOX;
-      
+  //
+  //  Fake node used for testing end-of-line potential breakpoint
+  //
+  var MO = MML.mo().With({SVGdata: {w: 0, x:0}});
+
   //
   //  Penalties for the various line breaks
   //
@@ -115,7 +119,7 @@ MathJax.Hub.Register.StartupHook("SVG Jax Ready",function () {
       //
       //  Break the expression at its best line breaks
       //
-      while (this.SVGbetterBreak(end,state) && 
+      while (this.SVGbetterBreak(end,state,true) && 
              (end.scanW >= SVG.linebreakWidth || end.penalty === PENALTY.newline)) {
         this.SVGaddLine(svg,start,end.index,state,end.values,broken);
         start = end.index.slice(0); broken = true;
@@ -145,7 +149,7 @@ MathJax.Hub.Register.StartupHook("SVG Jax Ready",function () {
     //
     //  Locate the next linebreak that is better than the current one
     //
-    SVGbetterBreak: function (info,state) {
+    SVGbetterBreak: function (info,state,toplevel) {
       if (this.isToken) {return false}  // FIXME: handle breaking of token elements
       if (this.isEmbellished()) {
         info.embellished = this;
@@ -177,6 +181,13 @@ MathJax.Hub.Register.StartupHook("SVG Jax Ready",function () {
         }
         info.index = []; i++; broken = false;
       }
+      //
+      //  Check if end-of-line is a better breakpoint
+      //
+      if (toplevel && better) {
+        MO.parent = this.parent; MO.inherit = this.inherit;
+        if (MO.SVGbetterBreak(info,state)) {better = false; index = info.index}
+      }
       if (info.nest) {info.nest--}
       info.index = index;
       if (better) {info.W = W}