From d3c636883a07266e52abb9941d86c4885df5de30 Mon Sep 17 00:00:00 2001
From: Stegmujo <johannesst@gmx.de>
Date: Thu, 5 Oct 2023 09:35:36 +0000
Subject: [PATCH] Render MathML for some letters used in mhchem

* \Alpha  \Beta  \Chi  \Epsilon  \Eta  \Iota  \Kappa  \Mu  \Nu  \Omicron  \Rho  \Tau  \Zeta
* \ca

Bug: T340024
Change-Id: I0d9d8314644927ccae0794ae8459a3f3893fc24a
---
 src/TexVC/MMLmappings/BaseMappings.php        | 14 ++++++++
 src/TexVC/MMLmappings/BaseParsing.php         | 12 +++++++
 .../unit/TexVC/Mhchem/MhchemBasicMMLTest.php  | 33 +++++++++++++++++++
 3 files changed, 59 insertions(+)

diff --git a/src/TexVC/MMLmappings/BaseMappings.php b/src/TexVC/MMLmappings/BaseMappings.php
index 04c1be2d8..847e10606 100644
--- a/src/TexVC/MMLmappings/BaseMappings.php
+++ b/src/TexVC/MMLmappings/BaseMappings.php
@@ -774,6 +774,20 @@ class BaseMappings {
 		"varointclockwise" => [ 'oint', '\u2232', [ "texClass" => TexClass::OP ] ],
 		"\\P" => [ 'oint', '\u00B6', [ "texClass" => TexClass::OP ] ],
 		'textvisiblespace' => [ 'Insert', '\u2423' ], // From TextCompMappings.js (only makro it seems)
+		"Alpha" => [ 'customLetters', "A" ],
+		"Beta" => [ 'customLetters', "B" ],
+		"Chi" => [ 'customLetters', "X" ],
+		"Epsilon" => [ 'customLetters', "E" ],
+		"Eta" => [ 'customLetters', "H" ],
+		"Iota" => [ 'customLetters', "I" ],
+		"Kappa" => [ 'customLetters', "K" ],
+		"Mu" => [ 'customLetters', "M" ],
+		"Nu" => [ 'customLetters', "N" ],
+		"Omicron" => [ 'customLetters', "O" ],
+		"Rho" => [ 'customLetters', "P" ],
+		"Tau" => [ 'customLetters', "T" ],
+		"Zeta" => [ 'customLetters', "Z" ],
+		"ca" => [ "customLetters", "&#x223C;", true ]
 	];
 
 	private const ALL = [
diff --git a/src/TexVC/MMLmappings/BaseParsing.php b/src/TexVC/MMLmappings/BaseParsing.php
index 5ed256d95..ff74878cf 100644
--- a/src/TexVC/MMLmappings/BaseParsing.php
+++ b/src/TexVC/MMLmappings/BaseParsing.php
@@ -211,6 +211,18 @@ class BaseParsing {
 		return "tbd chemCustom";
 	}
 
+	public static function customLetters( $node, $passedArgs, $operatorContent, $name, $char, $isOperator = false ) {
+		$mrow = new MMLmrow();
+
+		if ( $isOperator ) {
+			$mo = new MMLmo();
+			return $mrow->encapsulateRaw( $mo->encapsulateRaw( $char ) );
+		}
+
+		$mi = new MMLmi( "", [ "mathvariant" => "normal" ] );
+		return $mrow->encapsulateRaw( $mi->encapsulateRaw( $char ) );
+	}
+
 	public static function cFrac( $node, $passedArgs, $operatorContent, $name ) {
 		$mrow = new MMLmrow();
 		$mfrac = new MMLmfrac();
diff --git a/tests/phpunit/unit/TexVC/Mhchem/MhchemBasicMMLTest.php b/tests/phpunit/unit/TexVC/Mhchem/MhchemBasicMMLTest.php
index 7dadc7f9f..6f250e660 100644
--- a/tests/phpunit/unit/TexVC/Mhchem/MhchemBasicMMLTest.php
+++ b/tests/phpunit/unit/TexVC/Mhchem/MhchemBasicMMLTest.php
@@ -15,6 +15,39 @@ use MediaWikiUnitTestCase;
  */
 final class MhchemBasicMMLTest extends MediaWikiUnitTestCase {
 
+	public static function provideTestCasesLetters() {
+		return [
+			[ "Alpha" , "A" ],
+			[ "Beta" , "B" ] ,
+			[ "Chi" , "X" ],
+			[ "Epsilon" , "E" ],
+			[ "Eta" , "H" ],
+			[ "Iota" , "I" ],
+			[ "Kappa" , "K" ],
+			[ "Mu" , "M" ],
+			[ "Nu" , "N" ],
+			[ "Omicron" , "O" ],
+			[ "Rho" , "P" ],
+			[ "Tau" , "T" ],
+			[ "Zeta" , "Z" ]
+		];
+	}
+
+	/**
+	 * @dataProvider provideTestCasesLetters
+	 */
+	public function testmhchemLetters( $case, $result ) {
+		$input = "\ce{\\" . $case . " \ca }";
+		$texVC = new TexVC();
+		$options = [ "usemhchem" => true, "usemhchemtexified" => true ];
+		$warnings = [];
+		$res = $texVC->check( $input, $options, $warnings, true );
+		$mml = $res['input']->renderMML();
+		$this->assertStringContainsString( '<mi', $mml );
+		$this->assertStringContainsString( $result . '</mi>', $mml );
+		$this->assertStringContainsString( '<mo>&#x223C;</mo>', $mml );
+	}
+
 	public function testHarpoonsLeftRight() {
 		$input = "A \\longLeftrightharpoons L";
 		$texVC = new TexVC();