toTex: Escape special characters in strings

josdejong · Jan 31, 2018 · 9126130 · 9126130
1 parent 94ab164
commit 9126130
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Showing 4 changed files with 31 additions and 12 deletions.
diff --git a/lib/expression/node/ConstantNode.js b/lib/expression/node/ConstantNode.js
@@ -3,6 +3,7 @@
 var getType = require('../../utils/types').type;
 var stringify = require('../../utils/string').stringify;
 var escape = require('../../utils/string').escape;
+var escapeLatex = require('../../utils/latex').escape;
 
 function factory (type, config, load, typed) {
   var register = load(require('./compile')).register;
@@ -226,7 +227,7 @@ function factory (type, config, load, typed) {
         index;
     switch (this.valueType) {
       case 'string':
-        return '\\mathtt{' + stringify(value) + '}';
+        return '\\mathtt{' + escapeLatex(stringify(value)) + '}';
 
       case 'number':
         index = value.toLowerCase().indexOf('e');

diff --git a/lib/utils/latex.js b/lib/utils/latex.js
@@ -1,5 +1,7 @@
 'use strict';
 
+var escape_latex = require('escape-latex')
+
 exports.symbols = {
   // GREEK LETTERS
   Alpha: 'A',     alpha: '\\alpha',
@@ -80,6 +82,10 @@ var units = {
   deg: '^\\circ'
 };
 
+exports.escape = function (string) {
+  return escape_latex(string, {'preserveFormatting': true});
+}
+
 //@param {string} name
 //@param {boolean} isUnit
 exports.toSymbol = function (name, isUnit) {
@@ -88,17 +94,13 @@ exports.toSymbol = function (name, isUnit) {
     if (units.hasOwnProperty(name)) {
       return units[name];
     }
-    return '\\mathrm{' + name + '}';
+
+    return '\\mathrm{' + exports.escape(name) + '}';
   }
 
   if (exports.symbols.hasOwnProperty(name)) {
     return exports.symbols[name];
   }
-  else if (name.indexOf('_') !== -1) {
-    //symbol with index (eg. alpha_1)
-    var index = name.indexOf('_');
-    return exports.toSymbol(name.substring(0, index)) + '_{'
-      + exports.toSymbol(name.substring(index + 1)) + '}';
-  }
-  return name;
+
+  return exports.escape(name);
 };
diff --git a/test/expression/node/ConstantNode.test.js b/test/expression/node/ConstantNode.test.js
@@ -212,4 +212,10 @@ describe('ConstantNode', function() {
     assert.equal(n.toTex({handler: customFunction}), 'const\\left(1, number\\right)');
   });
 
+  it('should escape strings in toTex', function () {
+    var n = new ConstantNode('space tab\tunderscore_bla$/', 'string');
+
+    assert.equal(n.toTex(), '\\mathtt{"space~tab\\qquad{}underscore\\_bla\\$/"}');
+  });
+
 });
diff --git a/test/utils/latex.test.js b/test/utils/latex.test.js
@@ -2,11 +2,21 @@ var assert = require('assert'),
     latex = require('../../lib/utils/latex');
 
 describe('util.latex', function() {
-  it('should convert symbols with indices', function () {
-    assert.equal(latex.toSymbol('alpha_1'), '\\alpha_{1}');
+  it('should convert symbols with underscores', function () {
+    assert.equal(latex.toSymbol('alpha_1'), 'alpha\\_1');
   });
 
-  it('should convert units', function () {
+  it('should convert special units', function () {
     assert.equal(latex.toSymbol('deg', true), '^\\circ');
   });
+
+  it('should convert normal units', function () {
+    assert.equal(latex.toSymbol('cm', true), '\\mathrm{cm}');
+  });
+
+  it('should escape strings', function () {
+    var string = 'space tab\tunderscore_bla$/';
+
+    assert.equal(latex.toSymbol(string), 'space~tab\\qquad{}underscore\\_bla\\$/');
+  });
 });