add more unit tests and normalize the "__toString" methods

-> fix code style + psalm reported errors

src/DocBlock/Tags/Example.php

@@ -154,9 +154,15 @@ final class Example implements Tag, Factory\StaticMethod
         $content = (string) $this->content;
 
         return $filePath
-            . ($startingLine !== '' ? ($filePath !== '' ? ' ' : '') . $startingLine : '')
+            . ($startingLine !== ''
-            . ($lineCount !== '' ? ($filePath !== '' || $startingLine !== '' ? ' ' : '') . $lineCount : '')
+                ? ($filePath !== '' ? ' ' : '') . $startingLine
-            . ($content !== '' ? ($filePath !== '' || $startingLine !== '' || $lineCount !== '' ? ' ' : '') . $content : '');
+                : '')
+            . ($lineCount !== ''
+                ? ($filePath !== '' || $startingLine !== '' ? ' ' : '') . $lineCount
+                : '')
+            . ($content !== ''
+                ? ($filePath !== '' || $startingLine !== '' || $lineCount !== '' ? ' ' : '') . $content
+                : '');
     }
 
     /**

src/DocBlock/Tags/Method.php

@@ -212,6 +212,7 @@ final class Method extends BaseTag implements Factory\StaticMethod
         foreach ($this->arguments as $argument) {
             $arguments[] = $argument['type'] . ' $' . $argument['name'];
         }
+
         $argumentStr = '(' . implode(', ', $arguments) . ')';
 
         if ($this->description) {

src/DocBlock/Tags/Param.php

@@ -149,7 +149,7 @@ final class Param extends TagWithType implements Factory\StaticMethod
         $variableName = '';
         if ($this->variableName) {
             $variableName .= ($this->isReference ? '&' : '') . ($this->isVariadic ? '...' : '');
-            $variableName .= ($this->variableName ? '$' . $this->variableName : '');
+            $variableName .= '$' . $this->variableName;
         }
 
         $type = (string) $this->type;

src/DocBlock/Tags/Property.php

@@ -105,7 +105,7 @@ final class Property extends TagWithType implements Factory\StaticMethod
         }
 
         if ($this->variableName) {
-            $variableName = ($this->variableName ? '$' . $this->variableName : '');
+            $variableName = '$' . $this->variableName;
         } else {
             $variableName = '';
         }

src/DocBlock/Tags/PropertyRead.php

@@ -105,7 +105,7 @@ final class PropertyRead extends TagWithType implements Factory\StaticMethod
         }
 
         if ($this->variableName) {
-            $variableName = ($this->variableName ? '$' . $this->variableName : '');
+            $variableName = '$' . $this->variableName;
         } else {
             $variableName = '';
         }

src/DocBlock/Tags/PropertyWrite.php

@@ -105,7 +105,7 @@ final class PropertyWrite extends TagWithType implements Factory\StaticMethod
         }
 
         if ($this->variableName) {
-            $variableName = ($this->variableName ? '$' . $this->variableName : '');
+            $variableName = '$' . $this->variableName;
         } else {
             $variableName = '';
         }

src/DocBlock/Tags/Source.php

@@ -107,7 +107,7 @@ final class Source extends BaseTag implements Factory\StaticMethod
         $lineCount = $this->lineCount !== null ? '' . $this->lineCount : '';
 
         return $startingLine
-            . ($lineCount !== '' ? ($startingLine !== '' ? ' ' : '') . $lineCount : '')
+            . ($lineCount !== '' ? ($startingLine || $startingLine === '0' ? ' ' : '') . $lineCount : '')
-            . ($description !== '' ? ($startingLine !== '' || $lineCount !== '' ? ' ' : '') . $description : '');
+            . ($description !== '' ? ($startingLine || $startingLine === '0' || $lineCount !== '' ? ' ' : '') . $description : '');
     }
 }

src/DocBlock/Tags/Var_.php

@@ -106,7 +106,7 @@ final class Var_ extends TagWithType implements Factory\StaticMethod
         }
 
         if ($this->variableName) {
-            $variableName = ($this->variableName ? '$' . $this->variableName : '');
+            $variableName = '$' . $this->variableName;
         } else {
             $variableName = '';
         }