Implemented:

bool branchExistsRemotely();
	Check if branch exists in remote customer-repository.

    bool branchExistsLocally();
	Check if branch exists locally in customer-repository.

    bool gitPullNewBranches();
	In case the remote branch exists, but not the corresponding local one,
	then fetch the remote-branch.

UpdatePTUDevCtrl/git/git_client.cpp

@@ -6,6 +6,7 @@
 #include <QRegularExpression>
 #include <QDebug>
 #include <QDir>
+#include <QStringList>
 
 
 GitClient::GitClient(QString const &customerNrStr,
@@ -290,6 +291,100 @@ bool GitClient::gitFsck() {
     }
     return r;
 }
+
+bool GitClient::branchExistsRemotely() {
+    bool remoteBranchExists = false;
+    if (QDir(m_customerRepository).exists()) {
+        qInfo() << "BRANCH NAME" << m_branchName;
+        QString const cmd = QString("git ls-remote --exit-code --heads origin %1").arg(m_branchName);
+        Command c(cmd);
+        if (c.execute(m_customerRepository)) {
+            // expected result: c16c833c8778c1b3691a74afee5a469177e4e69b refs/heads/zg1/zone1000
+            QString const s = c.getCommandResult().trimmed();
+
+
+            if (!s.isEmpty()) {
+                // the result is only one line
+                if ((remoteBranchExists = s.contains(m_branchName)) == true) {
+                    qCritical() << "(" << __func__ << ":" << __LINE__ << ") branch"
+                                << m_branchName << "EXISTS REMOTELY. (" << s << ")";
+                }
+            } else {
+                Utils::printCriticalErrorMsg(QString("EMPTY RESULT FOR CMD %1").arg(cmd));
+            }
+        } else {
+            Utils::printCriticalErrorMsg(QString("FAILED TO EXEC '%1'").arg(cmd));
+        }
+    }
+    return remoteBranchExists;
+}
+
+bool GitClient::branchExistsLocally() {
+    Command c("git branch -l");
+    if (c.execute(m_customerRepository)) {
+        QString const s = c.getCommandResult().trimmed();
+        if (!s.isEmpty()) {
+            QStringList lines = Update::split(s, '\n');
+            if (!lines.empty()) {
+                for (int i=0; i < lines.size(); ++i) {
+                    QString line = lines.at(i);
+                    // expected: * [new branch]      zg1/zone12 -> origin/zg1/zone12"
+                    if (line.contains(m_branchName)) {
+                        if (m_worker) {
+                            QStringList lst(QString("BRANCH-NAME %1 CONTAINED IN RESULT %2").arg(m_branchName).arg(s));
+                            m_worker->CONSOLE(lst) << Worker::UPDATE_STEP::PULL_NEW_BRANCH;
+                        }
+                        return true;
+                    }
+                }
+
+                if (m_worker) {
+                    QStringList lst(QString("BRANCH-NAME %1 NOT CONTAINED IN RESULT %2").arg(m_branchName).arg(s));
+                    m_worker->CONSOLE(lst) << Worker::UPDATE_STEP::PULL_NEW_BRANCH_FAILURE;
+                }
+
+            } else {
+                if (m_worker) {
+                    QStringList lst(QString("'git branch -l' RETURNED NO LINES"));
+                    m_worker->CONSOLE(lst) << Worker::UPDATE_STEP::PULL_NEW_BRANCH_FAILURE;
+                }
+            }
+        } else {
+            if (m_worker) {
+                QStringList lst(QString("'git branch -l' RETURNED EMPTY RESULT"));
+                m_worker->CONSOLE(lst) << Worker::UPDATE_STEP::PULL_NEW_BRANCH_FAILURE;
+            }
+        }
+    } else {
+        if (m_worker) {
+            QStringList lst(QString("FAILED TO EXEC 'git branch -l'"));
+            m_worker->CONSOLE(lst) << Worker::UPDATE_STEP::PULL_NEW_BRANCH_FAILURE;
+        }
+    }
+
+    return false;
+}
+
+bool GitClient::gitPullNewBranches() {
+
+    if (QDir(m_customerRepository).exists()) {
+        Command c("git pull");
+        if (c.execute(m_customerRepository)) {
+            QString const s = c.getCommandResult().trimmed();
+            // expected: Already up-to-date.
+            if (!s.isEmpty()) {
+                QStringList lst;
+                QString msg(QString("GIT-PULL-NEW-BRANCH. RESULT=%1").arg(s));
+                if (m_worker) {
+                    m_worker->CONSOLE(lst) << Worker::UPDATE_STEP::PULL_NEW_BRANCH;
+                }
+                return true;
+            }
+        }
+    }
+    return false;
+}
+
 /*
  Hat sich nichts geaendert, so werden auch keine Commits <>..<> angezeigt
  */