From d57731b0d7ac78c2adc9f7a58a52b3c782e15d20 Mon Sep 17 00:00:00 2001
From: Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>
Date: Wed, 30 Jan 2013 23:19:08 +0000
Subject: [PATCH] QRegularExpression: print a warning if (?J) is used in a
 pattern

(?J) inside a pattern string can be used to allow or disallow duplicated
capturing group names in the pattern string itself.
Although PCRE supports duplicated names, in Qt we don't yet.

Change-Id: I21cd0c41273cd7ef42870ced3a0fad6ba7035cbc
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
---
 src/corelib/tools/qregularexpression.cpp      |  8 +++++
 .../tst_qregularexpression.cpp                | 32 +++++++++++++++++++
 .../tst_qregularexpression.h                  |  2 ++
 3 files changed, 42 insertions(+)

diff --git a/src/corelib/tools/qregularexpression.cpp b/src/corelib/tools/qregularexpression.cpp
index 706856c70b..9f29c1b576 100644
--- a/src/corelib/tools/qregularexpression.cpp
+++ b/src/corelib/tools/qregularexpression.cpp
@@ -1013,6 +1013,14 @@ void QRegularExpressionPrivate::getPatternInfo()
     usingCrLfNewlines = (patternNewlineSetting == PCRE_NEWLINE_CRLF) ||
             (patternNewlineSetting == PCRE_NEWLINE_ANY) ||
             (patternNewlineSetting == PCRE_NEWLINE_ANYCRLF);
+
+    int hasJOptionChanged;
+    pcre16_fullinfo(compiledPattern, 0, PCRE_INFO_JCHANGED, &hasJOptionChanged);
+    if (hasJOptionChanged) {
+        qWarning("QRegularExpressionPrivate::getPatternInfo(): the pattern '%s'\n"
+                 "    is using the (?J) option; duplicate capturing group names are not supported by Qt",
+                 qPrintable(pattern));
+    }
 }
 
 
diff --git a/tests/auto/corelib/tools/qregularexpression/tst_qregularexpression.cpp b/tests/auto/corelib/tools/qregularexpression/tst_qregularexpression.cpp
index 75487900d1..909725f4b8 100644
--- a/tests/auto/corelib/tools/qregularexpression/tst_qregularexpression.cpp
+++ b/tests/auto/corelib/tools/qregularexpression/tst_qregularexpression.cpp
@@ -1550,3 +1550,35 @@ void tst_QRegularExpression::regularExpressionMatch()
     QTest::ignoreMessage(QtWarningMsg, "QRegularExpressionMatch::captured: empty capturing group name passed");
     QCOMPARE(match.captured(QString()).isNull(), true);
 }
+
+void tst_QRegularExpression::JOptionUsage_data()
+{
+    QTest::addColumn<QString>("pattern");
+    QTest::addColumn<bool>("isValid");
+    QTest::addColumn<bool>("JOptionUsed");
+
+    QTest::newRow("joption-notused-01") << "a.*b" << true << false;
+    QTest::newRow("joption-notused-02") << "^a(b)(c)$" << true << false;
+    QTest::newRow("joption-notused-03") << "a(b)(?<c>d)|e" << true << false;
+    QTest::newRow("joption-notused-04") << "(?<a>.)(?<a>.)" << false << false;
+
+    QTest::newRow("joption-used-01") << "(?J)a.*b" << true << true;
+    QTest::newRow("joption-used-02") << "(?-J)a.*b" << true << true;
+    QTest::newRow("joption-used-03") << "(?J)(?<a>.)(?<a>.)" << true << true;
+    QTest::newRow("joption-used-04") << "(?-J)(?<a>.)(?<a>.)" << false << true;
+
+}
+
+void tst_QRegularExpression::JOptionUsage()
+{
+    QFETCH(QString, pattern);
+    QFETCH(bool, isValid);
+    QFETCH(bool, JOptionUsed);
+
+    const QString warningMessage = QStringLiteral("QRegularExpressionPrivate::getPatternInfo(): the pattern '%1'\n    is using the (?J) option; duplicate capturing group names are not supported by Qt");
+
+    QRegularExpression re(pattern);
+    if (isValid && JOptionUsed)
+        QTest::ignoreMessage(QtWarningMsg, qPrintable(warningMessage.arg(pattern)));
+    QCOMPARE(re.isValid(), isValid);
+}
diff --git a/tests/auto/corelib/tools/qregularexpression/tst_qregularexpression.h b/tests/auto/corelib/tools/qregularexpression/tst_qregularexpression.h
index 6de21f7cd0..0f62570114 100644
--- a/tests/auto/corelib/tools/qregularexpression/tst_qregularexpression.h
+++ b/tests/auto/corelib/tools/qregularexpression/tst_qregularexpression.h
@@ -78,6 +78,8 @@ private slots:
     void pcreJitStackUsage();
     void regularExpressionMatch_data();
     void regularExpressionMatch();
+    void JOptionUsage_data();
+    void JOptionUsage();
 
 private:
     void provideRegularExpressions();