StringUtils: Add trimFront(), trimBack() and trim() methods

Change-Id: I900c30111c79bee548c4861b082d7b035a5dc43d
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: Orgad Shaneh <orgads@gmail.com>

src/libs/utils/stringutils.cpp

@@ -454,6 +454,10 @@ QTCREATOR_UTILS_EXPORT QString normalizeNewlines(const QString &text)
     return res;
 }
 
+/*!
+    Joins all the not empty string list's \a strings into a single string with each element
+    separated by the given separator (which can be an empty string).
+*/
 QTCREATOR_UTILS_EXPORT QString joinStrings(const QStringList &strings, QChar separator)
 {
     QString result;
@@ -467,6 +471,52 @@ QTCREATOR_UTILS_EXPORT QString joinStrings(const QStringList &strings, QChar sep
     return result;
 }
 
+/*!
+    Returns a copy of \a string that has \a ch characters removed from the start.
+*/
+QTCREATOR_UTILS_EXPORT QString trimFront(const QString &string, QChar ch)
+{
+    const int size = string.size();
+    int i = 0;
+    while (i < size) {
+        if (string.at(i) != ch)
+            break;
+        ++i;
+    }
+    if (i == 0)
+        return string;
+    if (i == size)
+        return {};
+    return string.sliced(i);
+}
+
+/*!
+    Returns a copy of \a string that has \a ch characters removed from the end.
+*/
+QTCREATOR_UTILS_EXPORT QString trimBack(const QString &string, QChar ch)
+{
+    const int size = string.size();
+    int i = 0;
+    while (i < size) {
+        if (string.at(size - i - 1) != ch)
+            break;
+        ++i;
+    }
+    if (i == 0)
+        return string;
+    if (i == size)
+        return {};
+    return string.chopped(i);
+}
+
+/*!
+    Returns a copy of \a string that has \a ch characters removed from the start and the end.
+*/
+QTCREATOR_UTILS_EXPORT QString trim(const QString &string, QChar ch)
+{
+    return trimFront(trimBack(string, ch), ch);
+}
+
 QTCREATOR_UTILS_EXPORT QString appendHelper(const QString &base, int n)
 {
     return base + QString::number(n);

src/libs/utils/stringutils.h

@@ -111,6 +111,8 @@ QTCREATOR_UTILS_EXPORT QString normalizeNewlines(const QString &text);
 
 // Skips empty parts - see QTBUG-110900
 QTCREATOR_UTILS_EXPORT QString joinStrings(const QStringList &strings, QChar separator);
-
+QTCREATOR_UTILS_EXPORT QString trimFront(const QString &string, QChar ch);
+QTCREATOR_UTILS_EXPORT QString trimBack(const QString &string, QChar ch);
+QTCREATOR_UTILS_EXPORT QString trim(const QString &string, QChar ch);
 
 } // namespace Utils

tests/auto/utils/stringutils/tst_stringutils.cpp

@@ -75,6 +75,8 @@ private slots:
     void testParseUsedPortFromNetstatOutput();
     void testJoinStrings_data();
     void testJoinStrings();
+    void testTrim_data();
+    void testTrim();
 
 private:
     TestMacroExpander mx;
@@ -299,6 +301,35 @@ void tst_StringUtils::testJoinStrings()
     QCOMPARE(Utils::joinStrings(data.input, data.separator), data.output);
 }
 
+struct TrimData
+{
+    QString input;
+    QString front = {};
+    QString back = {};
+    QString bothSides = {};
+    QChar ch = ' ';
+};
+
+void tst_StringUtils::testTrim_data()
+{
+    QTest::addColumn<TrimData>("data");
+
+    QTest::newRow("Empty") << TrimData{};
+    QTest::newRow("AllToRemove") << TrimData{"   "};
+    QTest::newRow("BothSides") << TrimData{" foo ", "foo ", " foo", "foo"};
+    QTest::newRow("BothSidesLong") << TrimData{"  foo  ", "foo  ", "  foo", "foo"};
+    QTest::newRow("CharInside") << TrimData{"  foo bar  ", "foo bar  ", "  foo bar", "foo bar"};
+}
+
+void tst_StringUtils::testTrim()
+{
+    QFETCH(TrimData, data);
+
+    QCOMPARE(Utils::trimFront(data.input, data.ch), data.front);
+    QCOMPARE(Utils::trimBack(data.input, data.ch), data.back);
+    QCOMPARE(Utils::trim(data.input, data.ch), data.bothSides);
+}
+
 QTEST_GUILESS_MAIN(tst_StringUtils)
 
 #include "tst_stringutils.moc"