Reorganize some glyphs, simplify font selection, break \mathcal{123} (#2156)

* Reorganize some glyphs

* Remove mathdefault

Numerals are textord and it was never reachable.

* Use PUA for \imath and \jmath

* Update katex-fonts

* Update tests

* Update src/buildCommon.js

* Update screenshots

* Add comment regarding usage of PUA in \imath and \jmath

* Update fonts

Co-authored-by: Erik Demaine <edemaine@mit.edu>

src/buildCommon.js

@@ -8,7 +8,6 @@
 import {SymbolNode, Anchor, Span, PathNode, SvgNode, createClass} from "./domTree";
 import {getCharacterMetrics} from "./fontMetrics";
 import symbols, {ligatures} from "./symbols";
-import utils from "./utils";
 import {wideCharacterFont} from "./wide-character";
 import {calculateSize} from "./units";
 import {DocumentFragment} from "./tree";
@@ -21,13 +20,6 @@ import type {documentFragment as HtmlDocumentFragment} from "./domTree";
 import type {HtmlDomNode, DomSpan, SvgSpan, CssStyle} from "./domTree";
 import type {Measurement} from "./units";
 
-// The following have to be loaded from Main-Italic font, using class mathit
-const mathitLetters = [
-    "\\imath", "ı",       // dotless i
-    "\\jmath", "ȷ",       // dotless j
-    "\\pounds", "\\mathsterling", "\\textsterling", "£",   // pounds symbol
-];
-
 /**
  * Looks up the given symbol in fontMetrics, after applying any symbol
  * replacements defined in symbol.js
@@ -128,63 +120,6 @@ const mathsym = function(
     }
 };
 
-/**
- * Determines which of the two font names (Main-Italic and Math-Italic) and
- * corresponding style tags (mathdefault or mathit) to use for default math font,
- * depending on the symbol.
- */
-const mathdefault = function(
-    value: string,
-    mode: Mode,
-    options: Options,
-    classes: string[],
-): {| fontName: string, fontClass: string |} {
-    if (/[0-9]/.test(value.charAt(0)) ||
-            // glyphs for \imath and \jmath do not exist in Math-Italic so we
-            // need to use Main-Italic instead
-            utils.contains(mathitLetters, value)) {
-        return {
-            fontName: "Main-Italic",
-            fontClass: "mathit",
-        };
-    } else {
-        return {
-            fontName: "Math-Italic",
-            fontClass: "mathdefault",
-        };
-    }
-};
-
-/**
- * Determines which of the font names (Main-Italic, Math-Italic, and Caligraphic)
- * and corresponding style tags (mathit, mathdefault, or mathcal) to use for font
- * "mathnormal", depending on the symbol.  Use this function instead of fontMap for
- * font "mathnormal".
- */
-const mathnormal = function(
-    value: string,
-    mode: Mode,
-    options: Options,
-    classes: string[],
-): {| fontName: string, fontClass: string |} {
-    if (utils.contains(mathitLetters, value)) {
-        return {
-            fontName: "Main-Italic",
-            fontClass: "mathit",
-        };
-    } else if (/[0-9]/.test(value.charAt(0))) {
-        return {
-            fontName: "Caligraphic-Regular",
-            fontClass: "mathcal",
-        };
-    } else {
-        return {
-            fontName: "Math-Italic",
-            fontClass: "mathdefault",
-        };
-    }
-};
-
 /**
  * Determines which of the two font names (Main-Bold and Math-BoldItalic) and
  * corresponding style tags (mathbf or boldsymbol) to use for font "boldsymbol",
@@ -238,15 +173,10 @@ const makeOrd = function<NODETYPE: "spacing" | "mathord" | "textord">(
     } else if (fontOrFamily) {
         let fontName;
         let fontClasses;
-        if (fontOrFamily === "boldsymbol" || fontOrFamily === "mathnormal") {
-            const fontData = fontOrFamily === "boldsymbol"
-                ? boldsymbol(text, mode, options, classes, type)
-                : mathnormal(text, mode, options, classes);
+        if (fontOrFamily === "boldsymbol") {
+            const fontData = boldsymbol(text, mode, options, classes, type);
             fontName = fontData.fontName;
             fontClasses = [fontData.fontClass];
-        } else if (utils.contains(mathitLetters, text)) {
-            fontName = "Main-Italic";
-            fontClasses = ["mathit"];
         } else if (isFont) {
             fontName = fontMap[fontOrFamily].fontName;
             fontClasses = [fontOrFamily];
@@ -273,9 +203,8 @@ const makeOrd = function<NODETYPE: "spacing" | "mathord" | "textord">(
 
     // Makes a symbol in the default font for mathords and textords.
     if (type === "mathord") {
-        const fontLookup = mathdefault(text, mode, options, classes);
-        return makeSymbol(text, fontLookup.fontName, mode, options,
-            classes.concat([fontLookup.fontClass]));
+        return makeSymbol(text, "Math-Italic", mode, options,
+            classes.concat(["mathnormal"]));
     } else if (type === "textord") {
         const font = symbols[mode][text] && symbols[mode][text].font;
         if (font === "ams") {
@@ -754,13 +683,14 @@ const fontMap: {[string]: {| variant: FontVariant, fontName: string |}} = {
         variant: "italic",
         fontName: "Main-Italic",
     },
+    "mathnormal": {
+        variant: "italic",
+        fontName: "Math-Italic",
+    },
 
-    // Default math font, "mathnormal" and "boldsymbol" are missing because they
-    // require the use of several fonts: Main-Italic and Math-Italic for default
-    // math font, Main-Italic, Math-Italic, Caligraphic for "mathnormal", and
-    // Math-BoldItalic and Main-Bold for "boldsymbol".  This is handled by a
-    // special case in makeOrd which ends up calling mathdefault, mathnormal,
-    // and boldsymbol.
+    // "boldsymbol" is missing because they require the use of multiple fonts:
+    // Math-BoldItalic and Main-Bold.  This is handled by a special case in
+    // makeOrd which ends up calling boldsymbol.
 
     // families
     "mathbb": {

src/katex.less

@@ -84,7 +84,7 @@
     }
 
     // Math fonts.
-    .mathdefault {
+    .mathnormal {
         font-family: KaTeX_Math;
         font-style: italic;
     }

src/macros.js

@@ -855,6 +855,8 @@ defineMacro("\\varsubsetneq", "\\html@mathml{\\@varsubsetneq}{⊊}");
 defineMacro("\\varsubsetneqq", "\\html@mathml{\\@varsubsetneqq}{⫋}");
 defineMacro("\\varsupsetneq", "\\html@mathml{\\@varsupsetneq}{⊋}");
 defineMacro("\\varsupsetneqq", "\\html@mathml{\\@varsupsetneqq}{⫌}");
+defineMacro("\\imath", "\\html@mathml{\\@imath}{\u0131}");
+defineMacro("\\jmath", "\\html@mathml{\\@jmath}{\u0237}");
 
 //////////////////////////////////////////////////////////////////////
 // stmaryrd and semantic

src/symbols.js

@@ -681,8 +681,11 @@ defineSymbol(math, main, accent, "\u005e", "\\hat");
 defineSymbol(math, main, accent, "\u20d7", "\\vec");
 defineSymbol(math, main, accent, "\u02d9", "\\dot");
 defineSymbol(math, main, accent, "\u02da", "\\mathring");
-defineSymbol(math, main, mathord, "\u0131", "\\imath", true);
-defineSymbol(math, main, mathord, "\u0237", "\\jmath", true);
+// \imath and \jmath should be invariant to \mathrm, \mathbf, etc., so use PUA
+defineSymbol(math, main, mathord, "\ue131", "\\@imath");
+defineSymbol(math, main, mathord, "\ue237", "\\@jmath");
+defineSymbol(math, main, textord, "\u0131", "\u0131");
+defineSymbol(math, main, textord, "\u0237", "\u0237");
 defineSymbol(text, main, textord, "\u0131", "\\i", true);
 defineSymbol(text, main, textord, "\u0237", "\\j", true);
 defineSymbol(text, main, textord, "\u00df", "\\ss", true);
@@ -731,11 +734,11 @@ defineSymbol(text, main, textord, "\u00b0", "\\degree");
 // \textdegree from inputenc package
 defineSymbol(text, main, textord, "\u00b0", "\\textdegree", true);
 // TODO: In LaTeX, \pounds can generate a different character in text and math
-// mode, but among our fonts, only Main-Italic defines this character "163".
-defineSymbol(math, main, mathord, "\u00a3", "\\pounds");
-defineSymbol(math, main, mathord, "\u00a3", "\\mathsterling", true);
-defineSymbol(text, main, mathord, "\u00a3", "\\pounds");
-defineSymbol(text, main, mathord, "\u00a3", "\\textsterling", true);
+// mode, but among our fonts, only Main-Regular defines this character "163".
+defineSymbol(math, main, textord, "\u00a3", "\\pounds");
+defineSymbol(math, main, textord, "\u00a3", "\\mathsterling", true);
+defineSymbol(text, main, textord, "\u00a3", "\\pounds");
+defineSymbol(text, main, textord, "\u00a3", "\\textsterling", true);
 defineSymbol(math, ams, textord, "\u2720", "\\maltese");
 defineSymbol(text, ams, textord, "\u2720", "\\maltese");
 

src/wide-character.js

@@ -25,8 +25,8 @@ const wideLatinLetterData: Array<[string, string, string]> = [
     ["mathbf", "textbf", "Main-Bold"],                // A-Z bold upright
     ["mathbf", "textbf", "Main-Bold"],                // a-z bold upright
 
-    ["mathdefault", "textit", "Math-Italic"],         // A-Z italic
-    ["mathdefault", "textit", "Math-Italic"],         // a-z italic
+    ["mathnormal", "textit", "Math-Italic"],         // A-Z italic
+    ["mathnormal", "textit", "Math-Italic"],         // a-z italic
 
     ["boldsymbol", "boldsymbol", "Main-BoldItalic"],  // A-Z bold italic
     ["boldsymbol", "boldsymbol", "Main-BoldItalic"],  // a-z bold italic