Added support for Excel formula (#2219)

This adds support for Excel's formula terms.

components.json

@@ -307,6 +307,11 @@
 			"title": "Erlang",
 			"owner": "Golmote"
 		},
+		"excel-formula": {
+			"title": "Excel Formula",
+			"alias": ["xlsx", "xls"],
+			"owner": "RunDevelopment"
+		},
 		"fsharp": {
 			"title": "F#",
 			"require": "clike",

components/prism-excel-formula.js

@@ -0,0 +1,66 @@
+Prism.languages['excel-formula'] = {
+	'comment': {
+		pattern: /(\bN\(\s*)"(?:[^"]|"")*"(?=\s*\))/i,
+		lookbehind: true,
+		greedy: true
+	},
+	'string': {
+		pattern: /"(?:[^"]|"")*"(?!")/,
+		greedy: true
+	},
+	'reference': {
+		// https://www.ablebits.com/office-addins-blog/2015/12/08/excel-reference-another-sheet-workbook/
+
+		// Sales!B2
+		// 'Winter sales'!B2
+		// [Sales.xlsx]Jan!B2:B5
+		// D:\Reports\[Sales.xlsx]Jan!B2:B5
+		// '[Sales.xlsx]Jan sales'!B2:B5
+		// 'D:\Reports\[Sales.xlsx]Jan sales'!B2:B5
+
+		pattern: /(?:'[^']*'|(?:[^\s()[\]{}<>*?"';,$&]*\[[^^\s()[\]{}<>*?"']+\])?\w+)!/,
+		greedy: true,
+		alias: 'string',
+		inside: {
+			'operator': /!$/,
+			'punctuation': /'/,
+			'sheet': {
+				pattern: /[^[\]]+$/,
+				alias: 'function'
+			},
+			'file': {
+				pattern: /\[[^[\]]+\]$/,
+				inside: {
+					'punctuation': /[[\]]/
+				}
+			},
+			'path': /[\s\S]+/
+		}
+	},
+	'function-name': {
+		pattern: /[A-Z]\w*(?=\()/i,
+		alias: 'keyword'
+	},
+	'range': {
+		pattern: /\$?(?:[A-Z]+\$?\d+:\$?[A-Z]+\$?\d+|[A-Z]+:\$?[A-Z]+|\d+:\$?\d+)/i,
+		alias: 'property',
+		inside: {
+			'operator': /:/,
+			'cell': /\$?[A-Z]+\$?\d+/i,
+			'column': /\$?[A-Z]+/i,
+			'row': /\$?\d+/
+		}
+	},
+	'cell': {
+		// Excel is case insensitive, so the string "foo1" could be either a variable or a cell.
+		// To combat this, we match cells case insensitive, if the contain at least one "$", and case sensitive otherwise.
+		pattern: /[A-Z]+\d+|\$[A-Za-z]+\$?\d+|[A-Za-z]+\$\d+/,
+		alias: 'property'
+	},
+	'number': /(?:\b\d+(?:\.\d+)?|\B\.\d+)(?:e[+-]?\d+)?\b/i,
+	'boolean': /\b(?:TRUE|FALSE)\b/i,
+	'operator': /[-+*/^%=&,]|<[=>]?|>=?/,
+	'punctuation': /[[\]();{}|]/
+};
+
+Prism.languages['xlsx'] = Prism.languages['xls'] = Prism.languages['excel-formula'];

examples/prism-excel-formula.html

@@ -0,0 +1,10 @@
+<h2>Full example</h2>
+<pre><code>=SUM(G7*9)
+=INT(RAND()*999)
+=AVERAGE(A4:A13)+N("Average user rating")
+=CONCATENATE(F4, ",", " ", G4," ",H4)
+=IF($A4>500, $A4, 0)
+=AND($B4>=501,$C4&lt;=500)
+=SUBTOTAL(103,staff[Name])
+=TRIMMEAN(staff[Salary],10%)
+=SUM([Sales.xlsx]Jan!B2:B5)</code></pre>

plugins/autoloader/prism-autoloader.js

@@ -154,6 +154,8 @@
 		"jinja2": "django",
 		"dns-zone": "dns-zone-file",
 		"dockerfile": "docker",
+		"xlsx": "excel-formula",
+		"xls": "excel-formula",
 		"gamemakerlanguage": "gml",
 		"hs": "haskell",
 		"tex": "latex",

plugins/show-language/prism-show-language.js

@@ -57,6 +57,9 @@
 		"ejs": "EJS",
 		"etlua": "Embedded Lua templating",
 		"erb": "ERB",
+		"excel-formula": "Excel Formula",
+		"xlsx": "Excel Formula",
+		"xls": "Excel Formula",
 		"fsharp": "F#",
 		"firestore-security-rules": "Firestore security rules",
 		"ftl": "FreeMarker Template Language",

tests/languages/excel-formula/cell_feature.test

@@ -0,0 +1,27 @@
+B1
+BBB1111
+
+$B2
+B$2
+$B$2
+
+$b2
+b$2
+$b$2
+
+----------------------------------------------------
+
+[
+	["cell", "B1"],
+	["cell", "BBB1111"],
+	["cell", "$B2"],
+	["cell", "B$2"],
+	["cell", "$B$2"],
+	["cell", "$b2"],
+	["cell", "b$2"],
+	["cell", "$b$2"]
+]
+
+----------------------------------------------------
+
+Checks for cells.

tests/languages/excel-formula/function_feature.test

@@ -0,0 +1,17 @@
+SUM()
+FOO()
+
+----------------------------------------------------
+
+[
+	["function-name", "SUM"],
+	["punctuation", "("],
+	["punctuation", ")"],
+	["function-name", "FOO"],
+	["punctuation", "("],
+	["punctuation", ")"]
+]
+
+----------------------------------------------------
+
+Checks for functions.