summaryrefslogtreecommitdiffstats
path: root/src/script/parser/qscriptsyntaxchecker.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'src/script/parser/qscriptsyntaxchecker.cpp')
-rw-r--r--src/script/parser/qscriptsyntaxchecker.cpp188
1 files changed, 188 insertions, 0 deletions
diff --git a/src/script/parser/qscriptsyntaxchecker.cpp b/src/script/parser/qscriptsyntaxchecker.cpp
new file mode 100644
index 0000000..5883c69
--- /dev/null
+++ b/src/script/parser/qscriptsyntaxchecker.cpp
@@ -0,0 +1,188 @@
+/****************************************************************************
+**
+** Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Qt Software Information (qt-info@nokia.com)
+**
+** This file is part of the $MODULE$ of the Qt Toolkit.
+**
+** $TROLLTECH_DUAL_LICENSE$
+**
+****************************************************************************/
+
+#include "qscriptsyntaxchecker_p.h"
+
+#ifndef QT_NO_SCRIPT
+
+#include "qscriptlexer_p.h"
+#include "qscriptparser_p.h"
+
+QT_BEGIN_NAMESPACE
+
+namespace QScript {
+
+
+SyntaxChecker::SyntaxChecker():
+ tos(0),
+ stack_size(0),
+ state_stack(0)
+{
+}
+
+SyntaxChecker::~SyntaxChecker()
+{
+ if (stack_size) {
+ qFree(state_stack);
+ }
+}
+
+bool SyntaxChecker::automatic(QScript::Lexer *lexer, int token) const
+{
+ return token == T_RBRACE || token == 0 || lexer->prevTerminator();
+}
+
+SyntaxChecker::Result SyntaxChecker::checkSyntax(const QString &code)
+{
+ const int INITIAL_STATE = 0;
+ QScript::Lexer lexer (/*engine=*/ 0);
+ lexer.setCode(code, /*lineNo*/ 1);
+
+ int yytoken = -1;
+ int saved_yytoken = -1;
+ QString error_message;
+ int error_lineno = -1;
+ int error_column = -1;
+ State checkerState = Valid;
+
+ reallocateStack();
+
+ tos = 0;
+ state_stack[++tos] = INITIAL_STATE;
+
+ while (true)
+ {
+ const int state = state_stack [tos];
+ if (yytoken == -1 && - TERMINAL_COUNT != action_index [state])
+ {
+ if (saved_yytoken == -1)
+ yytoken = lexer.lex();
+ else
+ {
+ yytoken = saved_yytoken;
+ saved_yytoken = -1;
+ }
+ }
+
+ int act = t_action (state, yytoken);
+
+ if (act == ACCEPT_STATE) {
+ if (lexer.error() == QScript::Lexer::UnclosedComment)
+ checkerState = Intermediate;
+ else
+ checkerState = Valid;
+ break;
+ } else if (act > 0) {
+ if (++tos == stack_size)
+ reallocateStack();
+
+ state_stack [tos] = act;
+ yytoken = -1;
+ }
+
+ else if (act < 0)
+ {
+ int r = - act - 1;
+
+ tos -= rhs [r];
+ act = state_stack [tos++];
+
+ if ((r == Q_SCRIPT_REGEXPLITERAL_RULE1)
+ || (r == Q_SCRIPT_REGEXPLITERAL_RULE2)) {
+ // Skip the rest of the RegExp literal
+ bool rx = lexer.scanRegExp();
+ if (!rx) {
+ checkerState = Intermediate;
+ break;
+ }
+ }
+
+ state_stack [tos] = nt_action (act, lhs [r] - TERMINAL_COUNT);
+ }
+
+ else
+ {
+ if (saved_yytoken == -1 && automatic (&lexer, yytoken) && t_action (state, T_AUTOMATIC_SEMICOLON) > 0)
+ {
+ saved_yytoken = yytoken;
+ yytoken = T_SEMICOLON;
+ continue;
+ }
+
+ else if ((state == INITIAL_STATE) && (yytoken == 0)) {
+ // accept empty input
+ yytoken = T_SEMICOLON;
+ continue;
+ }
+
+ int ers = state;
+ int shifts = 0;
+ int reduces = 0;
+ int expected_tokens [3];
+ for (int tk = 0; tk < TERMINAL_COUNT; ++tk)
+ {
+ int k = t_action (ers, tk);
+
+ if (! k)
+ continue;
+ else if (k < 0)
+ ++reduces;
+ else if (spell [tk])
+ {
+ if (shifts < 3)
+ expected_tokens [shifts] = tk;
+ ++shifts;
+ }
+ }
+
+ error_message.clear ();
+ if (shifts && shifts < 3)
+ {
+ bool first = true;
+
+ for (int s = 0; s < shifts; ++s)
+ {
+ if (first)
+ error_message += QLatin1String ("Expected ");
+ else
+ error_message += QLatin1String (", ");
+
+ first = false;
+ error_message += QLatin1Char('`');
+ error_message += QLatin1String (spell [expected_tokens [s]]);
+ error_message += QLatin1Char('\'');
+ }
+ }
+
+ if (error_message.isEmpty())
+ error_message = lexer.errorMessage();
+
+ error_lineno = lexer.startLineNo();
+ error_column = lexer.startColumnNo();
+ checkerState = Error;
+ break;
+ }
+ }
+
+ if (checkerState == Error) {
+ if (lexer.error() == QScript::Lexer::UnclosedComment)
+ checkerState = Intermediate;
+ else if (yytoken == 0)
+ checkerState = Intermediate;
+ }
+ return Result(checkerState, error_lineno, error_column, error_message);
+}
+
+} // namespace QScript
+
+QT_END_NAMESPACE
+
+#endif // QT_NO_SCRIPT