Add default Editorconfig (#182)

https://editorconfig.org/
This standard file inscructs text editors about the whitespace rules to use in any given project, so that contributors will automatically use the correct convention.
I could see for instance that #168 introduced a mix of spaces and tabs

.editorconfig

@@ -0,0 +1,24 @@
+# http://EditorConfig.org
+
+[*]
+charset = utf-8
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+[*.json]
+indent_style = tab
+
+[*.md]
+indent_size = 4
+indent_style = tab
+
+[*.php]
+indent_style = tab
+
+[*.xml]
+indent_style = tab
+
+[*.yml]
+indent_size = 2
+indent_style = space

src/CssXPathException.php

@@ -3,4 +3,4 @@
 
 use RuntimeException;
 
-class CssXPathException extends RuntimeException {}
+class CssXPathException extends RuntimeException {}

src/NotYetImplementedException.php

@@ -1,4 +1,4 @@
 <?php
 namespace Gt\CssXPath;
 
-class NotYetImplementedException extends CssXPathException {}
+class NotYetImplementedException extends CssXPathException {}

src/Translator.php

@@ -61,7 +61,7 @@ protected function convertSingleSelector(string $css):string {
 		$thread = array_values($thread);
 
 		$xpath = [$this->prefix];
-        $hasElement = false;
+		$hasElement = false;
 		foreach($thread as $threadKey => $currentThreadItem) {
 			$next = isset($thread[$threadKey + 1])
 				? $thread[$threadKey + 1]
@@ -71,7 +71,7 @@ protected function convertSingleSelector(string $css):string {
 			case "star":
 			case "element":
 				$xpath []= $currentThreadItem['content'];
-                $hasElement = true;
+				$hasElement = true;
 				break;
 
 			case "pseudo":
@@ -161,7 +161,7 @@ protected function convertSingleSelector(string $css):string {
 
 			case "child":
 				array_push($xpath, "/");
-                $hasElement = false;
+				$hasElement = false;
 				break;
 
 			case "id":
@@ -170,31 +170,31 @@ protected function convertSingleSelector(string $css):string {
 					($hasElement ? '' : '*')
 					. "[@id='{$currentThreadItem['content']}']"
 				);
-                $hasElement = true;
+				$hasElement = true;
 				break;
 
 			case "class":
 				// https://devhints.io/xpath#class-check
 				array_push(
 					$xpath,
-                    ($hasElement ? '' : '*')
+					($hasElement ? '' : '*')
 					. "[contains(concat(' ',normalize-space(@class),' '),' {$currentThreadItem['content']} ')]"
 				);
-                $hasElement = true;
+				$hasElement = true;
 				break;
 
 			case "sibling":
 				array_push(
 					$xpath,
 					"/following-sibling::*[1]/self::"
 				);
-                $hasElement = false;
+				$hasElement = false;
 				break;
 
 			case "attribute":
 				if(!$hasElement) {
 					array_push($xpath, "*");
-                    $hasElement = true;
+					$hasElement = true;
 				}
 
 				/** @var null|array<int, array<string, string>> $detail */
@@ -263,7 +263,7 @@ protected function convertSingleSelector(string $css):string {
 
 			case "descendant":
 				array_push($xpath, "//");
-                $hasElement = false;
+				$hasElement = false;
 				break;
 			}
 		}

test/phpunit/Helper/Helper.php

@@ -32,13 +32,13 @@ class Helper {
 			<span>Site logo</span>
 		</a>
 	</h1>
-	
+
 	<nav class="c-menu main-selection">
 		<input type="checkbox" id="toggle-menu" />
 		<label for="toggle-menu">
 			<span>Menu</span>
 		</label>
-		
+
 		<ul>
 			<li>
 				<a href="/">Home</a>
@@ -58,7 +58,7 @@ class Helper {
 
 <main>
 	<p>I'm a paragraph, but I'm not part of the article.</p>
-	
+
 	<article>
 		<header>
 			<h1>
@@ -111,24 +111,24 @@ class Helper {
 	<label>
 		<span>From:</span>
 		<select name="from">
-			<option>0</option>		
-			<option>1</option>		
-			<option>2</option>		
-			<option>3</option>		
-			<option>4</option>		
-			<option>5</option>		
+			<option>0</option>
+			<option>1</option>
+			<option>2</option>
+			<option>3</option>
+			<option>4</option>
+			<option>5</option>
 		</select>
 	</label>
-	
+
 	<label>
 		<span>To:</span>
 		<select name="to">
-			<option>5</option>		
-			<option>6</option>		
-			<option>7</option>		
-			<option>8</option>		
-			<option>9</option>		
-			<option>10</option>		
+			<option>5</option>
+			<option>6</option>
+			<option>7</option>
+			<option>8</option>
+			<option>9</option>
+			<option>10</option>
 		</select>
 	</label>
 </form>
@@ -138,7 +138,7 @@ class Helper {
 <!doctype html>
 <form method="post">
 	<p>Please select and of the following:</p>
-	
+
 	<label>
 		<input type="checkbox" name="choice[]" value="1" />
 		<span>Choice 1</span>
@@ -151,12 +151,12 @@ class Helper {
 		<input type="checkbox" name="choice[]" value="3" />
 		<span>Choice 3</span>
 	</label>
-	
+
 	<button>Submit</button>
 </form>
 HTML;
 
-    const HTML_SELECTORS = <<<HTML
+	const HTML_SELECTORS = <<<HTML
 <!doctype html>
 <html>
 <head>