Merge pull request #6 from mficzel/task/throwExceptionsOnSytaxErrors

Task/throw exceptions on sytax errors

Author: grebaldi

src/Expression/Expression.php

@@ -10,13 +10,16 @@ public static function parse(Lexer $lexer)
     {
         $contents = '';
         $braceCount = 0;
+
         if ($lexer->isOpeningBrace()) {
             $lexer->consume();
+        } else {
+            throw new Exception('Expression without braces');
         }
 
         while (true) {
             if ($lexer->isEnd()) {
-                throw new Exception('Unclosed Expression');
+                throw new Exception(sprintf('Unfinished Expression "%s"', $contents));
             }
 
             if ($lexer->isOpeningBrace()) {

src/Expression/Identifier.php

@@ -8,9 +8,6 @@ class Identifier
     public static function parse(Lexer $lexer)
     {
         $identifier = '';
-        if ($lexer->isAlpha()) {
-            $identifier .= $lexer->consume();
-        }
 
         while ($lexer->isAlphaNumeric() ||
             $lexer->isDot() ||

src/Expression/Node.php

@@ -45,44 +45,61 @@ public static function parse(Lexer $lexer)
                     'children' => $children,
                     'selfClosing' => true
                 ];
+            } else {
+                throw new Exception(sprintf('Self closing tag "%s" misses closing bracket.', $identifier));
             }
         }
 
         if ($lexer->isClosingBracket()) {
             $lexer->consume();
+        } else {
+            throw new Exception(sprintf('Tag "%s" did not end with closing bracket.', $identifier));
         }
 
         $children = Children::parse($lexer);
 
-        while ($lexer->isWhitespace()) {
-            $lexer->consume();
-        }
-
         if ($lexer->isOpeningBracket()) {
             $lexer->consume();
 
             if ($lexer->isForwardSlash()) {
                 $lexer->consume();
+            } else {
+                throw new Exception(sprintf(
+                    'Opening-bracket for closing of tag "%s" was not followed by slash.',
+                    $identifier
+                ));
             }
+        } else {
+            throw new Exception(sprintf(
+                'Opening-bracket for closing of tag "%s" expected.',
+                $identifier
+            ));
         }
 
         $closingIdentifier = Identifier::parse($lexer);
 
+        if ($closingIdentifier !== $identifier) {
+            throw new Exception(sprintf(
+                'Closing-tag identifier "%s" did not match opening-tag identifier "%s".',
+                $closingIdentifier,
+                $identifier
+            ));
+        }
+
         if ($lexer->isClosingBracket()) {
             $lexer->consume();
-
-            if ($closingIdentifier === $identifier) {
-                return [
-                    'identifier' => $identifier,
-                    'props' => $props,
-                    'children' => $children,
-                    'selfClosing' => false
-                ];
-            }
+            return [
+                'identifier' => $identifier,
+                'props' => $props,
+                'children' => $children,
+                'selfClosing' => false
+            ];
+        } else {
+            throw new Exception(sprintf('Closing tag "%s" did not end with closing-bracket.', $identifier));
         }
 
         if ($lexer->isEnd()) {
-            throw new Exception(sprintf('Tag %s was is not closed', $identifier));
+            throw new Exception(sprintf('Tag "%s" was is not closed.', $identifier));
         }
     }
 }

src/Expression/Prop.php

@@ -1,6 +1,7 @@
 <?php
 namespace PackageFactory\Afx\Expression;
 
+use PackageFactory\Afx\Exception;
 use PackageFactory\Afx\Lexer;
 
 class Prop
@@ -12,39 +13,37 @@ public static function parse(Lexer $lexer)
         }
 
         $identifier = Identifier::parse($lexer);
-        $value = [
-            'type' => 'boolean',
-            'payload' => false
-        ];
 
         if ($lexer->isEqualSign()) {
             $lexer->consume();
-        }
-
-        switch (true) {
-            case $lexer->isSingleQuote():
-            case $lexer->isDoubleQuote():
-                $value = [
-                'type' => 'string',
-                'payload' => StringLiteral::parse($lexer)
-                ];
-                break;
-
-            case $lexer->isOpeningBrace():
-                $value = [
-                'type' => 'expression',
-                'payload' => Expression::parse($lexer)
-                ];
-                break;
-
-            case $lexer->isWhiteSpace():
-            case $lexer->isForwardSlash():
-            case $lexer->isClosingBracket():
-                $value = [
+            switch (true) {
+                case $lexer->isSingleQuote():
+                case $lexer->isDoubleQuote():
+                    $value = [
+                        'type' => 'string',
+                        'payload' => StringLiteral::parse($lexer)
+                    ];
+                    break;
+
+                case $lexer->isOpeningBrace():
+                    $value = [
+                        'type' => 'expression',
+                        'payload' => Expression::parse($lexer)
+                    ];
+                    break;
+                default:
+                    throw new Exception(sprintf(
+                        'Prop-assignment "%s" was not followed by quotes or braces',
+                        $identifier
+                    ));
+            }
+        } elseif ($lexer->isWhiteSpace() || $lexer->isForwardSlash() || $lexer->isClosingBracket()) {
+            $value = [
                 'type' => 'boolean',
                 'payload' => true
-                ];
-                break;
+            ];
+        } else {
+            throw new Exception(sprintf('Prop identifier "%s" is neither assignment nor boolean', $identifier));
         }
 
         return [$identifier, $value];

src/Expression/StringLiteral.php

@@ -13,11 +13,13 @@ public static function parse(Lexer $lexer)
         $willBeEscaped = false;
         if ($lexer->isSingleQuote() || $lexer->isDoubleQuote()) {
             $openingQuoteSign = $lexer->consume();
+        } else {
+            throw new Exception('Unquoted String literal');
         }
 
         while (true) {
             if ($lexer->isEnd()) {
-                throw new Exception('Unclosed string literal');
+                throw new Exception(sprintf('Unfinished string literal "%s"', $contents));
             }
 
             if ($lexer->isBackSlash() && !$willBeEscaped) {