Fixed error handling for wrong string escape sequences.

smuuf · Dec 20, 2024 · 7514756 · 7514756
1 parent 62f6147
commit 7514756
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Showing 5 changed files with 77 additions and 39 deletions.
diff --git a/src/Ex/WrongEscapeSequenceException.php b/src/Ex/WrongEscapeSequenceException.php
@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Smuuf\Primi\Ex;
+
+/**
+ * StringEscaping can throw this.
+ *
+ * @internal
+ */
+class WrongEscapeSequenceException extends EngineException {
+
+	/**
+	 * @param string $piece Which character was tried to be used as part of
+	 *     escape sequence? For example "č" in "\č".
+	 */
+	public function __construct(
+		public readonly string $char,
+	) {
+		parent::__construct("Unrecognized string escape sequence '{$char}'");
+	}
+
+}
diff --git a/src/Handlers/Kinds/FStringLiteral.php b/src/Handlers/Kinds/FStringLiteral.php
@@ -10,6 +10,8 @@
 use Smuuf\Primi\Helpers\Interned;
 use Smuuf\Primi\Helpers\StringEscaping;
 use Smuuf\Primi\Compiler\Compiler;
+use Smuuf\Primi\Ex\InternalSyntaxError;
+use Smuuf\Primi\Ex\WrongEscapeSequenceException;
 use Smuuf\Primi\Handlers\Handler;
 
 class FStringLiteral extends Handler {
@@ -25,30 +27,36 @@ public static function reduce(array &$node): void {
 		// 2. FStringExpr nodes as node array.
 		// ... which will be easy to handle during compilation
 
-		$parts = [];
-		foreach (Func::ensure_indexed($node['core']['parts']) as $part) {
+		try {
 
-			// Extract "just text" from the non-expr nodes, so we don't have
-			// to deal with them later.
-			if ($part['name'] === 'FStringTxt') {
+			$parts = [];
+			foreach (Func::ensure_indexed($node['core']['parts']) as $part) {
 
-				// Convert double-curly-braces in ordinary text subnodes
-				// to single ones.
-				$part = \str_replace(['{{', '}}'], ['{', '}'], $part['text']);
-				$part = StringEscaping::unescapeString($part);
-				$parts[] = $part;
+				// Extract "just text" from the non-expr nodes, so we don't have
+				// to deal with them later.
+				if ($part['name'] === 'FStringTxt') {
 
-			} elseif ($part['name'] === 'FStringExpr') {
+					// Convert double-curly-braces in ordinary text subnodes
+					// to single ones.
+					$part = \str_replace(['{{', '}}'], ['{', '}'], $part['text']);
+					$part = StringEscaping::unescapeString($part);
+					$parts[] = $part;
 
-				// Keep f-string's nested-expression nodes as-is.
-				$parts[] = $part;
+				} elseif ($part['name'] === 'FStringExpr') {
+
+					// Keep f-string's nested-expression nodes as-is.
+					$parts[] = $part;
+
+				} else {
+					throw new EngineInternalError(
+						"Unknown node type encountered when parsing f-string"
+					);
+				}
 
-			} else {
-				throw new EngineInternalError(
-					"Unknown node type encountered when parsing f-string"
-				);
 			}
 
+		} catch (WrongEscapeSequenceException $exc) {
+			throw InternalSyntaxError::fromNode($node, $exc->getMessage());
 		}
 
 		$node['parts'] = $parts;

diff --git a/src/Handlers/Kinds/StringLiteral.php b/src/Handlers/Kinds/StringLiteral.php
@@ -5,9 +5,11 @@
 namespace Smuuf\Primi\Handlers\Kinds;
 
 use Smuuf\Primi\VM\Machine;
-use Smuuf\Primi\Compiler\Compiler;
+use Smuuf\Primi\Ex\InternalSyntaxError;
+use Smuuf\Primi\Ex\WrongEscapeSequenceException;
 use Smuuf\Primi\Helpers\Interned;
 use Smuuf\Primi\Helpers\StringEscaping;
+use Smuuf\Primi\Compiler\Compiler;
 use Smuuf\Primi\Handlers\Handler;
 
 class StringLiteral extends Handler {
@@ -17,7 +19,14 @@ class StringLiteral extends Handler {
 	 */
 	public static function reduce(array &$node): void {
 
-		$node['text'] = StringEscaping::unescapeString($node['core']['text']);
+		try {
+			$node['text'] = StringEscaping::unescapeString(
+				$node['core']['text'],
+			);
+		} catch (WrongEscapeSequenceException $exc) {
+			throw InternalSyntaxError::fromNode($node, $exc->getMessage());
+		}
+
 		unset($node['quote']);
 		unset($node['core']);
 

diff --git a/src/Helpers/StringEscaping.php b/src/Helpers/StringEscaping.php
@@ -4,6 +4,8 @@
 
 namespace Smuuf\Primi\Helpers;
 
+use Smuuf\Primi\Ex\InternalSyntaxError;
+use Smuuf\Primi\Ex\WrongEscapeSequenceException;
 use Smuuf\Primi\Stdlib\StaticExceptionTypes;
 use Smuuf\StrictObject;
 
@@ -51,10 +53,7 @@ public static function unescapeString(string $str): string {
 
 			// The backslashed character doesn't represent any known escape
 			// sequence, therefore error.
-			Exceptions::piggyback(
-				StaticExceptionTypes::getRuntimeErrorType(),
-				"Unrecognized string escape sequence '{$m[0]}'.",
-			);
+			throw new WrongEscapeSequenceException($m[0]);
 
 		}, $str);
 

diff --git a/src/VM/Machine.php b/src/VM/Machine.php
@@ -29,6 +29,7 @@
 use Smuuf\Primi\Helpers\Exceptions;
 use Smuuf\Primi\ScopeComposite;
 use Smuuf\Primi\Structures\CallArgs;
+use Smuuf\Primi\Values\ExceptionValue;
 
 class Machine {
 
@@ -396,24 +397,23 @@ public function run(Frame $frame): AbstractValue {
 							unset($a, $b);
 							goto vm_check_exc;
 						}
-						$vStack->push($b);
+						$vStack->push($b); // @phpstan-ignore-line
 						unset($a, $b);
 						break;
 
 					case Machine::OP_CALL_FUNCTION_EX:
 						// Pop 1: Kwargs dict.
 						// Pop 2: Args list.
 						// Pop 3: Callable object.
-						/**
-						 * @var AbstractValue $a
-						 * @var AbstractValue $b
-						 * @var AbstractValue $c
-						 */
+						/** @var AbstractValue */
 						$a = $vStack->pop();
+						/** @var AbstractValue */
 						$b = $vStack->pop();
+						/** @var AbstractValue */
+						$c = $vStack->pop();
 						$frame->storeOpIndex($opIndex);
 						$scope->setVariables($locals);
-						$c = $vStack->pop()->invoke(
+						$c = $c->invoke(
 							$ctx,
 							new CallArgs(
 								$b->getCoreValue(),
@@ -424,19 +424,21 @@ public function run(Frame $frame): AbstractValue {
 							unset($a, $b, $c);
 							goto vm_check_exc;
 						}
-						$vStack->push($c);
+						$vStack->push($c); // @phpstan-ignore-line
 						unset($a, $b, $c);
 						break;
 
 					case Machine::OP_CALL_FUNCTION_N:
+						/** @var AbstractValue */
+						$a = $vStack->pop();
 						$frame->storeOpIndex($opIndex);
 						$scope->setVariables($locals);
-						$a = $vStack->pop()->invoke($ctx);
+						$a = $a->invoke($ctx);
 						if ($ctx->getPendingException()) {
 							unset($a);
 							goto vm_check_exc;
 						}
-						$vStack->push($a);
+						$vStack->push($a); // @phpstan-ignore-line
 						unset($a);
 						break;
 
@@ -463,7 +465,6 @@ public function run(Frame $frame): AbstractValue {
 						// Arg #1: A list array of key-value pairs, for example:
 						//         [['key', 'value'], ...]
 						$vStack->push(new DictValue($op[1]));
-						unset($a, $b, $i, $pairs);
 						break;
 
 					case Machine::OP_BUILD_DICT:
@@ -635,15 +636,14 @@ public function run(Frame $frame): AbstractValue {
 							$op[2],
 							$op[3],
 							$ctx,
-							$scope,
-							$builtins,
 						);
 						$vStack->push($a);
 						unset($a);
 						break;
 
 					case Machine::OP_EXC_THROW:
 						// Pop #1: ExceptionValue.
+						/** @var ExceptionValue */
 						$a = $vStack->pop();
 						$frame->storeOpIndex($opIndex);
 						if (Types::isSubtypeOf($a->getType(), StaticExceptionTypes::getBaseExceptionType())) {
@@ -655,17 +655,15 @@ public function run(Frame $frame): AbstractValue {
 								"Only exceptions can be thrown",
 							);
 						}
-						goto vm_check_exc;
 						unset($a);
-						break;
+						goto vm_check_exc;
 
 					case Machine::OP_IMPORT:
 						// Arg #1: Dotpath of the module to be imported.
 						// Arg #2: List of names to import.
 						$scope->setVariables($locals);
 						ImportStatement::handleImport($ctx, $op[1], $op[2]);
 						goto vm_check_exc;
-						break;
 
 					case Machine::OP_RETURN:
 						goto vm_loop_exit;