Replace Iosevka with JetBrains Mono, fix scrollbar and inline edit UX

- Replace embedded Iosevka font with JetBrains Mono as default font
- Fix wide horizontal scrollbar by enabling SCI_SETSCROLLWIDTHTRACKING
- Remove 28-char trailing whitespace padding from all lines
- Fix arrow keys not collapsing selection in inline edit mode
- Dim struct/array braces ({ and };) to match hex node styling
- Resize margin immediately on font change

src/compose.cpp

@@ -18,6 +18,7 @@ struct ComposeState {
     int                currentLine = 0;
     int                typeW       = kColType;  // global type column width (fallback)
     int                nameW       = kColName;  // global name column width (fallback)
+    int                offsetHexDigits = 8;     // hex digit tier for offset margin
     bool               baseEmitted = false;     // only first root struct shows base address
 
     // Precomputed for O(1) lookups
@@ -144,7 +145,7 @@ void composeLeaf(ComposeState& state, const NodeTree& tree,
         lm.isContinuation  = isCont;
         lm.lineKind        = isCont ? LineKind::Continuation : LineKind::Field;
         lm.nodeKind        = node.kind;
-        lm.offsetText      = fmt::fmtOffsetMargin(tree.baseAddress + absAddr, isCont);
+        lm.offsetText      = fmt::fmtOffsetMargin(tree.baseAddress + absAddr, isCont, state.offsetHexDigits);
         lm.markerMask      = computeMarkers(node, prov, absAddr, isCont, depth);
         lm.foldLevel       = computeFoldLevel(depth, false);
         lm.effectiveTypeW  = typeW;
@@ -191,7 +192,7 @@ void composeParent(ComposeState& state, const NodeTree& tree,
         lm.nodeId     = node.id;
         lm.depth      = depth;
         lm.lineKind   = LineKind::Field;
-        lm.offsetText = fmt::fmtOffsetMargin(tree.baseAddress + absAddr, false);
+        lm.offsetText = fmt::fmtOffsetMargin(tree.baseAddress + absAddr, false, state.offsetHexDigits);
         lm.nodeKind   = node.kind;
         lm.markerMask = (1u << M_CYCLE) | (1u << M_ERR);
         lm.foldLevel  = computeFoldLevel(depth, false);
@@ -208,7 +209,7 @@ void composeParent(ComposeState& state, const NodeTree& tree,
         lm.nodeId     = node.id;
         lm.depth      = depth;
         lm.lineKind   = LineKind::ArrayElementSeparator;
-        lm.offsetText = fmt::fmtOffsetMargin(tree.baseAddress + absAddr, false);
+        lm.offsetText = fmt::fmtOffsetMargin(tree.baseAddress + absAddr, false, state.offsetHexDigits);
         lm.nodeKind   = node.kind;
         lm.foldLevel  = computeFoldLevel(depth, false);
         lm.markerMask = 0;
@@ -234,7 +235,7 @@ void composeParent(ComposeState& state, const NodeTree& tree,
         lm.nodeId     = node.id;
         lm.depth      = depth;
         lm.lineKind   = LineKind::Header;
-        lm.offsetText = fmt::fmtOffsetMargin(tree.baseAddress + absAddr, false);
+        lm.offsetText = fmt::fmtOffsetMargin(tree.baseAddress + absAddr, false, state.offsetHexDigits);
         lm.nodeKind   = node.kind;
         lm.isRootHeader = false;
         lm.foldHead      = true;
@@ -288,10 +289,10 @@ void composeParent(ComposeState& state, const NodeTree& tree,
         lm.lineKind   = LineKind::Footer;
         lm.nodeKind   = node.kind;
         lm.isRootHeader = isRootHeader;  // root footer: flush left (no fold prefix)
-        lm.offsetText.clear();
         lm.foldLevel  = computeFoldLevel(depth, false);
         lm.markerMask = 0;
         int sz = tree.structSpan(node.id, &state.childMap);
+        lm.offsetText = fmt::fmtOffsetMargin(tree.baseAddress + absAddr + sz, false, state.offsetHexDigits);
         state.emitLine(fmt::fmtStructFooter(node, depth, sz), lm);
     }
 
@@ -322,7 +323,7 @@ void composeNode(ComposeState& state, const NodeTree& tree,
             lm.nodeId     = node.id;
             lm.depth      = depth;
             lm.lineKind   = node.collapsed ? LineKind::Field : LineKind::Header;
-            lm.offsetText = fmt::fmtOffsetMargin(tree.baseAddress + absAddr, false);
+            lm.offsetText = fmt::fmtOffsetMargin(tree.baseAddress + absAddr, false, state.offsetHexDigits);
             lm.nodeKind   = node.kind;
             lm.foldHead      = true;
             lm.foldCollapsed = node.collapsed;
@@ -411,6 +412,19 @@ ComposeResult compose(const NodeTree& tree, const Provider& prov, uint64_t viewR
     for (int i = 0; i < tree.nodes.size(); i++)
         state.absOffsets[i] = tree.computeOffset(i);
 
+    // Compute hex digit tier from max absolute address
+    {
+        uint64_t maxAddr = tree.baseAddress;
+        for (int i = 0; i < tree.nodes.size(); i++) {
+            uint64_t addr = tree.baseAddress + (uint64_t)state.absOffsets[i];
+            if (addr > maxAddr) maxAddr = addr;
+        }
+        if      (maxAddr <= 0xFFFFULL)             state.offsetHexDigits = 4;
+        else if (maxAddr <= 0xFFFFFFFFULL)         state.offsetHexDigits = 8;
+        else if (maxAddr <= 0xFFFFFFFFFFFFULL)     state.offsetHexDigits = 12;
+        else                                        state.offsetHexDigits = 16;
+    }
+
     // Helper: compute the display type string for a node (for width calculation)
     auto nodeTypeName = [&](const Node& n) -> QString {
         if (n.kind == NodeKind::Array)
@@ -491,7 +505,7 @@ ComposeResult compose(const NodeTree& tree, const Provider& prov, uint64_t viewR
         lm.lineKind  = LineKind::CommandRow;
         lm.foldLevel = SC_FOLDLEVELBASE;
         lm.foldHead  = false;
-        lm.offsetText = fmt::fmtOffsetMargin(tree.baseAddress, false);
+        lm.offsetText = fmt::fmtOffsetMargin(tree.baseAddress, false, state.offsetHexDigits);
         lm.markerMask = 0;
         lm.effectiveTypeW = state.typeW;
         lm.effectiveNameW = state.nameW;
@@ -510,7 +524,7 @@ ComposeResult compose(const NodeTree& tree, const Provider& prov, uint64_t viewR
         composeNode(state, tree, prov, idx, 0);
     }
 
-    return { state.text, state.meta, LayoutInfo{state.typeW, state.nameW} };
+    return { state.text, state.meta, LayoutInfo{state.typeW, state.nameW, state.offsetHexDigits} };
 }
 
 QSet<uint64_t> NodeTree::normalizePreferAncestors(const QSet<uint64_t>& ids) const {

src/controller.cpp

@@ -1496,7 +1496,7 @@ void RcxController::showTypeSelectorPopup(RcxEditor* editor) {
 
     // Get font with zoom
     QSettings settings("ReclassX", "ReclassX");
-    QString fontName = settings.value("font", "Consolas").toString();
+    QString fontName = settings.value("font", "JetBrains Mono").toString();
     QFont font(fontName, 12);
     font.setFixedPitch(true);
     auto* sci = editor->scintilla();

src/core.h

@@ -439,6 +439,7 @@ inline bool isSyntheticLine(const LineMeta& lm) {
 struct LayoutInfo {
     int typeW = 14;  // Effective type column width (default = kColType)
     int nameW = 22;  // Effective name column width (default = kColName)
+    int offsetHexDigits = 8;  // Hex digits for offset margin (4/8/12/16)
 };
 
 // ── ComposeResult ──
@@ -750,7 +751,7 @@ namespace fmt {
                         uint64_t addr, int depth, int subLine = 0,
                         const QString& comment = {}, int colType = kColType, int colName = kColName,
                         const QString& typeOverride = {});
-    QString fmtOffsetMargin(uint64_t absoluteOffset, bool isContinuation);
+    QString fmtOffsetMargin(uint64_t absoluteOffset, bool isContinuation, int hexDigits = 8);
     QString fmtStructHeader(const Node& node, int depth, bool collapsed, int colType = kColType, int colName = kColName);
     QString fmtStructFooter(const Node& node, int depth, int totalSize = -1);
     QString fmtArrayHeader(const Node& node, int depth, int viewIdx, bool collapsed, int colType = kColType, int colName = kColName);

src/editor.cpp

@@ -32,7 +32,7 @@ static constexpr int IND_DATA_CHANGED = 13; // Amber text for changed data value
 static constexpr int IND_CLASS_NAME   = 14; // Teal text for root class name
 static constexpr int IND_HINT_GREEN   = 15; // Green text for hint/comment text
 
-static QString g_fontName = "Consolas";
+static QString g_fontName = "JetBrains Mono";
 
 static QFont editorFont() {
     QFont f(g_fontName, 12);
@@ -139,6 +139,10 @@ void RcxEditor::setupScintilla() {
     m_sci->SendScintilla(QsciScintillaBase::SCI_SETSELFORE, (long)0, (long)0);
     m_sci->SendScintilla(QsciScintillaBase::SCI_SETSELBACK, (long)0, (long)0);
 
+    // Auto-size horizontal scrollbar to actual content width (default is fixed 2000px)
+    m_sci->SendScintilla(QsciScintillaBase::SCI_SETSCROLLWIDTHTRACKING, 1);
+    m_sci->SendScintilla(QsciScintillaBase::SCI_SETSCROLLWIDTH, 1);
+
     // Editable-field indicator - HIDDEN (no visual)
     m_sci->SendScintilla(QsciScintillaBase::SCI_INDICSETSTYLE,
                          IND_EDITABLE, 5 /*INDIC_HIDDEN*/);
@@ -240,7 +244,7 @@ void RcxEditor::setupMargins() {
 
     // Margin 0: Offset text
     m_sci->setMarginType(0, QsciScintilla::TextMarginRightJustified);
-    m_sci->setMarginWidth(0, "  0x00000000  ");
+    m_sci->setMarginWidth(0, "  00000000  ");  // default 8-digit; resized dynamically in applyDocument()
     m_sci->setMarginsBackgroundColor(kBgMargin);
     m_sci->setMarginsForegroundColor(kFgMarginDim);
     m_sci->setMarginSensitivity(0, true);
@@ -346,10 +350,18 @@ void RcxEditor::applyDocument(const ComposeResult& result) {
     m_meta = result.meta;
     m_layout = result.layout;
 
+    // Dynamically resize margin to fit the current hex digit tier
+    QString marginSizer = QString("  %1  ").arg(QString(m_layout.offsetHexDigits, '0'));
+    m_sci->setMarginWidth(0, marginSizer);
+
     m_sci->setReadOnly(false);
     m_sci->setText(result.text);
     m_sci->setReadOnly(true);
 
+    // Reset scroll width so tracking re-measures from current content
+    // (tracking never shrinks automatically — only grows)
+    m_sci->SendScintilla(QsciScintillaBase::SCI_SETSCROLLWIDTH, 1);
+
     // Force full re-lex to fix stale syntax coloring after edits
     m_sci->SendScintilla(QsciScintillaBase::SCI_COLOURISE, (uintptr_t)0, (long)-1);
 
@@ -370,7 +382,6 @@ void RcxEditor::applyDocument(const ComposeResult& result) {
 }
 
 void RcxEditor::applyMarginText(const QVector<LineMeta>& meta) {
-    // Clear all margin text
     m_sci->clearMarginText(-1);
 
     for (int i = 0; i < meta.size(); i++) {
@@ -450,6 +461,21 @@ void RcxEditor::applyHexDimming(const QVector<LineMeta>& meta) {
             if (len > 0)
                 m_sci->SendScintilla(QsciScintillaBase::SCI_INDICATORFILLRANGE, pos, len);
         }
+        // Dim struct/array braces: entire footer line, trailing "{" on headers
+        if (meta[i].lineKind == LineKind::Footer) {
+            long pos, len; lineRangeNoEol(m_sci, i, pos, len);
+            if (len > 0)
+                m_sci->SendScintilla(QsciScintillaBase::SCI_INDICATORFILLRANGE, pos, len);
+        } else if (meta[i].lineKind == LineKind::Header) {
+            long endPos = m_sci->SendScintilla(QsciScintillaBase::SCI_GETLINEENDPOSITION, (unsigned long)i);
+            for (long p = endPos - 1; p >= 0; --p) {
+                int ch = (int)m_sci->SendScintilla(QsciScintillaBase::SCI_GETCHARAT, (unsigned long)p);
+                if (ch == ' ' || ch == '\t') continue;
+                if (ch == '{')
+                    m_sci->SendScintilla(QsciScintillaBase::SCI_INDICATORFILLRANGE, p, 1);
+                break;
+            }
+        }
     }
 }
 
@@ -1351,12 +1377,30 @@ bool RcxEditor::handleEditKey(QKeyEvent* ke) {
             if (lineText.mid(m_editState.spanStart, 2).startsWith(QStringLiteral("0x"), Qt::CaseInsensitive))
                 minCol = m_editState.spanStart + 2;
         }
+        // If there's an active selection, collapse it to the left end (Left only, not Backspace)
+        if (ke->key() == Qt::Key_Left) {
+            int sL, sC, eL, eC;
+            m_sci->getSelection(&sL, &sC, &eL, &eC);
+            if (sL >= 0 && (sL != eL || sC != eC)) {
+                int leftEnd = qMax(qMin(sC, eC), minCol);
+                m_sci->setCursorPosition(m_editState.line, leftEnd);
+                return true;
+            }
+        }
         if (col <= minCol) return true;
         return false;
     }
     case Qt::Key_Right: {
         int line, col;
         m_sci->getCursorPosition(&line, &col);
+        // If there's an active selection, collapse it to the right end first
+        int sL, sC, eL, eC;
+        m_sci->getSelection(&sL, &sC, &eL, &eC);
+        if (sL >= 0 && (sL != eL || sC != eC)) {
+            int rightEnd = qMin(qMax(sC, eC), editEndCol());
+            m_sci->setCursorPosition(m_editState.line, rightEnd);
+            return true;
+        }
         if (col >= editEndCol()) return true;  // block past end
         return false;
     }
@@ -1468,8 +1512,9 @@ bool RcxEditor::beginInlineEdit(EditTarget target, int line) {
         m_editState.editKind = NodeKind::Float;
 
     // Store fixed comment column position for value editing
+    // Use large lineLength so commentCol is always computed (padding added dynamically)
     if (target == EditTarget::Value) {
-        ColumnSpan cs = commentSpanFor(*lm, lineText.size(), lm->effectiveTypeW, lm->effectiveNameW);
+        ColumnSpan cs = commentSpanFor(*lm, 9999, lm->effectiveTypeW, lm->effectiveNameW);
         m_editState.commentCol = cs.valid ? cs.start : -1;
         m_editState.lastValidationOk = true;  // original value is always valid
     } else {
@@ -1480,6 +1525,26 @@ bool RcxEditor::beginInlineEdit(EditTarget target, int line) {
     m_sci->SendScintilla(QsciScintillaBase::SCI_SETUNDOCOLLECTION, (long)0);
     m_sci->SendScintilla(QsciScintillaBase::SCI_SETCARETWIDTH, 1);
     m_sci->setReadOnly(false);
+
+    // For value editing: extend line with trailing spaces for the edit comment area
+    // (comment padding is no longer baked into every line to avoid unnecessary scroll width)
+    if (target == EditTarget::Value && m_editState.commentCol >= 0) {
+        int commentStart = norm.end + 2;
+        int neededLen = commentStart + kColComment;
+        int currentLen = (int)lineText.size();
+        if (currentLen < neededLen) {
+            int extend = neededLen - currentLen;
+            long lineEndPos = posFromCol(m_sci, line, currentLen);
+            QString pad(extend, ' ');
+            QByteArray padUtf8 = pad.toUtf8();
+            m_sci->SendScintilla(QsciScintillaBase::SCI_SETTARGETSTART, lineEndPos);
+            m_sci->SendScintilla(QsciScintillaBase::SCI_SETTARGETEND, lineEndPos);
+            m_sci->SendScintilla(QsciScintillaBase::SCI_REPLACETARGET,
+                                 (uintptr_t)padUtf8.size(), padUtf8.constData());
+            m_editState.linelenAfterReplace += extend;
+        }
+    }
+
     // Switch to I-beam for editing (skip for picker-based targets)
     if (target != EditTarget::Type && target != EditTarget::Source
         && target != EditTarget::ArrayElementType && target != EditTarget::PointerTarget
@@ -2079,8 +2144,10 @@ void RcxEditor::setEditorFont(const QString& fontName) {
         m_lexer->setFont(f, i);
     m_sci->setMarginsFont(f);
 
-    // Re-apply margin styles with new font
+    // Re-apply margin styles and width with new font metrics
     allocateMarginStyles();
+    QString marginSizer = QString("  %1  ").arg(QString(m_layout.offsetHexDigits, '0'));
+    m_sci->setMarginWidth(0, marginSizer);
 }
 
 void RcxEditor::setGlobalFontName(const QString& fontName) {

src/format.cpp

@@ -111,9 +111,10 @@ QString indent(int depth) {
 
 // ── Offset margin ──
 
-QString fmtOffsetMargin(uint64_t absoluteOffset, bool isContinuation) {
+QString fmtOffsetMargin(uint64_t absoluteOffset, bool isContinuation, int hexDigits) {
     if (isContinuation) return QStringLiteral("  \u00B7 ");
-    return QString::number(absoluteOffset, 16).toUpper() + QChar(' ');
+    return QString::number(absoluteOffset, 16).toUpper()
+               .rightJustified(hexDigits, '0') + QChar(' ');
 }
 
 // ── Struct type name (for width calculation) ──
@@ -313,8 +314,8 @@ QString fmtNodeLine(const Node& node, const Provider& prov,
     // Blank prefix for continuation lines (same width as type+sep+name+sep)
     const int prefixW = colType + colName + 2 * kSepWidth;
 
-    // Comment suffix (padded or empty)
+    // Comment suffix (only present when a comment is provided; no trailing padding)
-    QString cmtSuffix = comment.isEmpty() ? QString(COL_COMMENT, ' ')
+    QString cmtSuffix = comment.isEmpty() ? QString()
                                           : fit(comment, COL_COMMENT);
 
     // Mat4x4: subLine 0..3 = rows

src/main.cpp

@@ -315,16 +315,16 @@ void MainWindow::createMenus() {
     auto* actConsolas = fontMenu->addAction("Consolas");
     actConsolas->setCheckable(true);
     actConsolas->setActionGroup(fontGroup);
-    auto* actIosevka = fontMenu->addAction("Iosevka");
+    auto* actJetBrains = fontMenu->addAction("JetBrains Mono");
-    actIosevka->setCheckable(true);
+    actJetBrains->setCheckable(true);
-    actIosevka->setActionGroup(fontGroup);
+    actJetBrains->setActionGroup(fontGroup);
     // Load saved preference
     QSettings settings("ReclassX", "ReclassX");
-    QString savedFont = settings.value("font", "Consolas").toString();
+    QString savedFont = settings.value("font", "JetBrains Mono").toString();
-    if (savedFont == "Iosevka") actIosevka->setChecked(true);
+    if (savedFont == "JetBrains Mono") actJetBrains->setChecked(true);
     else actConsolas->setChecked(true);
     connect(actConsolas, &QAction::triggered, this, [this]() { setEditorFont("Consolas"); });
-    connect(actIosevka, &QAction::triggered, this, [this]() { setEditorFont("Iosevka"); });
+    connect(actJetBrains, &QAction::triggered, this, [this]() { setEditorFont("JetBrains Mono"); });
 
     view->addSeparator();
     view->addAction(m_workspaceDock->toggleViewAction());
@@ -353,7 +353,7 @@ void MainWindow::createStatusBar() {
     statusBar()->setStyleSheet("QStatusBar { background: #252526; color: #858585; }");
 
     QSettings settings("ReclassX", "ReclassX");
-    QString fontName = settings.value("font", "Consolas").toString();
+    QString fontName = settings.value("font", "JetBrains Mono").toString();
     QFont f(fontName, 12);
     f.setFixedPitch(true);
     statusBar()->setFont(f);
@@ -361,7 +361,7 @@ void MainWindow::createStatusBar() {
 
 void MainWindow::applyTabWidgetStyle(QTabWidget* tw) {
     QSettings settings("ReclassX", "ReclassX");
-    QString fontName = settings.value("font", "Consolas").toString();
+    QString fontName = settings.value("font", "JetBrains Mono").toString();
     QFont tabFont(fontName, 12);
     tabFont.setFixedPitch(true);
     tw->tabBar()->setFont(tabFont);
@@ -813,7 +813,7 @@ void MainWindow::updateWindowTitle() {
 
 void MainWindow::setupRenderedSci(QsciScintilla* sci) {
     QSettings settings("ReclassX", "ReclassX");
-    QString fontName = settings.value("font", "Consolas").toString();
+    QString fontName = settings.value("font", "JetBrains Mono").toString();
     QFont f(fontName, 12);
     f.setFixedPitch(true);
 
@@ -1112,7 +1112,7 @@ void MainWindow::createWorkspaceDock() {
     // Match editor font
     {
         QSettings settings("ReclassX", "ReclassX");
-        QString fontName = settings.value("font", "Consolas").toString();
+        QString fontName = settings.value("font", "JetBrains Mono").toString();
         QFont f(fontName, 12);
         f.setFixedPitch(true);
         m_workspaceTree->setFont(f);
@@ -1299,13 +1299,13 @@ int main(int argc, char* argv[]) {
     app.setStyle("Fusion"); // Fusion style respects dark palette well
 
     // Load embedded fonts
-    int fontId = QFontDatabase::addApplicationFont(":/fonts/Iosevka-Regular.ttf");
+    int fontId = QFontDatabase::addApplicationFont(":/fonts/JetBrainsMono.ttf");
     if (fontId == -1)
-        qWarning("Failed to load embedded Iosevka font");
+        qWarning("Failed to load embedded JetBrains Mono font");
     // Apply saved font preference before creating any editors
     {
         QSettings settings("ReclassX", "ReclassX");
-        QString savedFont = settings.value("font", "Consolas").toString();
+        QString savedFont = settings.value("font", "JetBrains Mono").toString();
         rcx::RcxEditor::setGlobalFontName(savedFont);
     }
 

src/resources.qrc

@@ -4,7 +4,7 @@
         <file alias="chevron-down.png">icons/chevron-down.png</file>
     </qresource>
     <qresource prefix="/fonts">
-        <file alias="Iosevka-Regular.ttf">fonts/Iosevka-Regular.ttf</file>
+        <file alias="JetBrainsMono.ttf">fonts/JetBrainsMono.ttf</file>
     </qresource>
     <qresource prefix="/vsicons">
         <file alias="file.svg">vsicons/file.svg</file>

tests/test_compose.cpp

@@ -48,8 +48,8 @@ private slots:
         QCOMPARE(result.meta[2].depth, 1);
 
         // Offset text
-        QCOMPARE(result.meta[1].offsetText, QString("0"));
+        QCOMPARE(result.meta[1].offsetText, QString("0000 "));
-        QCOMPARE(result.meta[2].offsetText, QString("4"));
+        QCOMPARE(result.meta[2].offsetText, QString("0004 "));
 
         // Line 3 is root footer
         QCOMPARE(result.meta[3].lineKind, LineKind::Footer);
@@ -81,7 +81,7 @@ private slots:
 
         // Line 1: single Vec3 line, not continuation, depth 1
         QVERIFY(!result.meta[1].isContinuation);
-        QCOMPARE(result.meta[1].offsetText, QString("0"));
+        QCOMPARE(result.meta[1].offsetText, QString("0000 "));
         QCOMPARE(result.meta[1].depth, 1);
         QCOMPARE(result.meta[1].nodeKind, NodeKind::Vec3);
 

tests/test_format.cpp

@@ -39,12 +39,21 @@ private slots:
     }
 
     void testFmtOffsetMargin_primary() {
-        QCOMPARE(fmt::fmtOffsetMargin(0x10, false), QString("10"));
+        QCOMPARE(fmt::fmtOffsetMargin(0x10, false), QString("00000010 "));
-        QCOMPARE(fmt::fmtOffsetMargin(0, false),    QString("0"));
+        QCOMPARE(fmt::fmtOffsetMargin(0, false),    QString("00000000 "));
     }
 
     void testFmtOffsetMargin_continuation() {
-        QCOMPARE(fmt::fmtOffsetMargin(0x10, true), QString("  \u00B7"));
+        QCOMPARE(fmt::fmtOffsetMargin(0x10, true), QString("  \u00B7 "));
+    }
+
+    void testFmtOffsetMargin_kernelAddr() {
+        QCOMPARE(fmt::fmtOffsetMargin(0xFFFFF80012345678ULL, false, 16),
+                 QString("FFFFF80012345678 "));
+        QCOMPARE(fmt::fmtOffsetMargin(0x10, false, 16),
+                 QString("0000000000000010 "));
+        QCOMPARE(fmt::fmtOffsetMargin(0x10, false, 4),
+                 QString("0010 "));
     }
 
     void testFmtStructHeader() {