Import JSC-based Qt Script from Kent's tree.

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