Add lint rule to unify self-closing tags format (#6513)

* Add lint rule to unify closing tags format

* Apply suggestions from code review

* Simplify lint rule logic

* Clarify error message

* Fix 'extraneous' rule and remove part of 'svg-format'

Co-authored-by: Eric Cornelissen <ericornelissen@gmail.com>

.svglintrc.js

@@ -485,7 +485,7 @@ module.exports = {
           function(reporter, $, ast) {
             reporter.name = "extraneous";
 
-            if (!svgRegexp.test($.html())) {
+            if (!svgRegexp.test(ast.source)) {
               reporter.error("Unexpected character(s), most likely extraneous whitespace, detected in SVG markup");
             }
           },
@@ -569,6 +569,16 @@ module.exports = {
                 reporter.error(`${errorMsg}: ${reason}`);
               }
             }
+          },
+          function(reporter, $, ast) {
+            reporter.name = 'svg-format';
+
+            // Don't allow explicit '</path>' closing tag
+            if (ast.source.includes('</path>')) {
+              const reason = `found a closing "path" tag at index ${ast.source.indexOf('</path>')}.`
+                          + ' The path should be self-closing, use \'/>\' instead of \'></path>\'.';
+              reporter.error(`Invalid SVG content format: ${reason}`);
+            }
           }
         ]
     }

icons/cytoscapedotjs.svg

@@ -1 +1 @@
-<svg role="img" viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg"><title>Cytoscape.js</title><path d="M24 0v24H0V0h24zm-4.8416 7.2596c-.939 0-1.7199.6988-1.8416 1.61l-2.7097.6834a1.8574 1.8574 0 00-1.5505-.834c-1.026 0-1.858.832-1.858 1.858 0 1.0259.832 1.8579 1.858 1.8579.2554 0 .5063-.052.7388-.1528l1.792 1.8298a2.0325 2.0325 0 00-.0493.0932l-2.3452-.316c-.1616-.868-.9238-1.5154-1.8264-1.5154-1.0259 0-1.858.832-1.858 1.858 0 1.0258.8321 1.858 1.858 1.858a1.859 1.859 0 001.6365-.9776l2.3456.316c.0214.1408.0573.2788.1074.412l-.984.8666a1.136 1.136 0 00-.3179-.0454c-.626 0-1.1337.5077-1.1337 1.1338 0 .6258.5078 1.1336 1.1337 1.1336.626 0 1.1336-.5078 1.1336-1.1336 0-.0496-.0031-.0988-.0096-.1476l.9446-.832c.34.2325.7417.3572 1.1578.3572.082 0 .1638-.0048.245-.0145l.8342 1.665a1.8536 1.8536 0 00-.5009 1.269c0 1.0258.8322 1.858 1.8581 1.858 1.026 0 1.858-.8322 1.858-1.858 0-1.026-.832-1.8581-1.858-1.8581-.0873 0-.1743.006-.2604.0182l-.8039-1.6046a2.0519 2.0519 0 00.6834-1.5305 2.0553 2.0553 0 00-.9357-1.724l.7343-2.4191c.9905-.04 1.7818-.856 1.7818-1.8565 0-1.0259-.8321-1.858-1.858-1.858zm-1.582 2.8326c.1244.2014.2862.3776.4762.5185l-.7442 2.4523a2.046 2.046 0 00-.8189.2015l-1.787-1.8249a1.8483 1.8483 0 00.2025-.6736z"></path></svg>
+<svg role="img" viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg"><title>Cytoscape.js</title><path d="M24 0v24H0V0h24zm-4.8416 7.2596c-.939 0-1.7199.6988-1.8416 1.61l-2.7097.6834a1.8574 1.8574 0 00-1.5505-.834c-1.026 0-1.858.832-1.858 1.858 0 1.0259.832 1.8579 1.858 1.8579.2554 0 .5063-.052.7388-.1528l1.792 1.8298a2.0325 2.0325 0 00-.0493.0932l-2.3452-.316c-.1616-.868-.9238-1.5154-1.8264-1.5154-1.0259 0-1.858.832-1.858 1.858 0 1.0258.8321 1.858 1.858 1.858a1.859 1.859 0 001.6365-.9776l2.3456.316c.0214.1408.0573.2788.1074.412l-.984.8666a1.136 1.136 0 00-.3179-.0454c-.626 0-1.1337.5077-1.1337 1.1338 0 .6258.5078 1.1336 1.1337 1.1336.626 0 1.1336-.5078 1.1336-1.1336 0-.0496-.0031-.0988-.0096-.1476l.9446-.832c.34.2325.7417.3572 1.1578.3572.082 0 .1638-.0048.245-.0145l.8342 1.665a1.8536 1.8536 0 00-.5009 1.269c0 1.0258.8322 1.858 1.8581 1.858 1.026 0 1.858-.8322 1.858-1.858 0-1.026-.832-1.8581-1.858-1.8581-.0873 0-.1743.006-.2604.0182l-.8039-1.6046a2.0519 2.0519 0 00.6834-1.5305 2.0553 2.0553 0 00-.9357-1.724l.7343-2.4191c.9905-.04 1.7818-.856 1.7818-1.8565 0-1.0259-.8321-1.858-1.858-1.858zm-1.582 2.8326c.1244.2014.2862.3776.4762.5185l-.7442 2.4523a2.046 2.046 0 00-.8189.2015l-1.787-1.8249a1.8483 1.8483 0 00.2025-.6736z"/></svg>