[UI] add line wrapping functionality

README.md

@@ -114,18 +114,34 @@ struct MathView: UIViewRepresentable {
     var fontSize: CGFloat = 30
     var labelMode: MTMathUILabelMode = .text
     var insets: MTEdgeInsets = MTEdgeInsets()
-    
+
     func makeUIView(context: Context) -> MTMathUILabel {
         let view = MTMathUILabel()
+        view.setContentHuggingPriority(.required, for: .vertical)
+        view.setContentCompressionResistancePriority(.required, for: .vertical)
         return view
     }
+
     func updateUIView(_ view: MTMathUILabel, context: Context) {
         view.latex = equation
-        view.font = MTFontManager().font(withName: font.rawValue, size: fontSize)
+        let font = MTFontManager().font(withName: font.rawValue, size: fontSize)
+        font?.fallbackFont = UIFont.systemFont(ofSize: fontSize)
+        view.font = font
         view.textAlignment = textAlignment
         view.labelMode = labelMode
         view.textColor = MTColor(Color.primary)
         view.contentInsets = insets
+        view.invalidateIntrinsicContentSize()
+    }
+
+    func sizeThatFits(_ proposal: ProposedViewSize, uiView: MTMathUILabel, context: Context) -> CGSize? {
+        // Enable line wrapping by passing proposed width to the label
+        if let width = proposal.width, width.isFinite, width > 0 {
+            uiView.preferredMaxLayoutWidth = width
+            let size = uiView.sizeThatFits(CGSize(width: width, height: .greatestFiniteMagnitude))
+            return size
+        }
+        return nil
     }
 }
 ```
@@ -143,23 +159,127 @@ struct MathView: NSViewRepresentable {
     var fontSize: CGFloat = 30
     var labelMode: MTMathUILabelMode = .text
     var insets: MTEdgeInsets = MTEdgeInsets()
-    
+
     func makeNSView(context: Context) -> MTMathUILabel {
         let view = MTMathUILabel()
+        view.setContentHuggingPriority(.required, for: .vertical)
+        view.setContentCompressionResistancePriority(.required, for: .vertical)
         return view
     }
-    
+
     func updateNSView(_ view: MTMathUILabel, context: Context) {
         view.latex = equation
-        view.font = MTFontManager().font(withName: font.rawValue, size: fontSize)
+        let font = MTFontManager().font(withName: font.rawValue, size: fontSize)
+        font?.fallbackFont = NSFont.systemFont(ofSize: fontSize)
+        view.font = font
         view.textAlignment = textAlignment
         view.labelMode = labelMode
         view.textColor = MTColor(Color.primary)
         view.contentInsets = insets
+        view.invalidateIntrinsicContentSize()
+    }
+
+    func sizeThatFits(_ proposal: ProposedViewSize, nsView: MTMathUILabel, context: Context) -> CGSize? {
+        // Enable line wrapping by passing proposed width to the label
+        if let width = proposal.width, width.isFinite, width > 0 {
+            nsView.preferredMaxLayoutWidth = width
+            let size = nsView.sizeThatFits(CGSize(width: width, height: .greatestFiniteMagnitude))
+            return size
+        }
+        return nil
     }
 }
 ```
 
+### Automatic Line Wrapping
+
+`SwiftMath` supports automatic line wrapping for text and simple math expressions. When the content exceeds the available width, it will wrap at word boundaries to fit within the constrained space.
+
+#### Using Line Wrapping with UIKit/AppKit
+
+For direct `MTMathUILabel` usage, set the `preferredMaxLayoutWidth` property:
+
+```swift
+let label = MTMathUILabel()
+label.latex = "\\(\\text{Remember the conversion: 1 km equals 1000 meters.}\\)"
+label.font = MTFontManager.fontManager.defaultFont
+label.labelMode = .text
+
+// Enable line wrapping by setting a maximum width
+label.preferredMaxLayoutWidth = 300
+```
+
+You can also use `sizeThatFits` to calculate the size with a width constraint:
+
+```swift
+let constrainedSize = label.sizeThatFits(CGSize(width: 300, height: .greatestFiniteMagnitude))
+```
+
+#### Using Line Wrapping with SwiftUI
+
+The `MathView` examples above include `sizeThatFits()` which automatically enables line wrapping when SwiftUI proposes a width constraint. No additional configuration is needed:
+
+```swift
+VStack(alignment: .leading, spacing: 8) {
+    MathView(
+        equation: "\\(\\text{Remember the conversion: 1 km equals 1000 meters.}\\)",
+        fontSize: 17,
+        labelMode: .text
+    )
+}
+.frame(maxWidth: 300)  // The text will wrap to fit within 300pt
+```
+
+#### Line Wrapping Behavior
+
+- **Works for**: Text content (`\text{...}`), mixed text with simple math, and simple equations
+- **Breaks at**: Word boundaries (spaces)
+- **Preserves**: Complex math layout (fractions, superscripts, matrices remain on single lines)
+- **Respects**: Unicode text including CJK characters with proper word boundaries
+
+#### Examples
+
+**Simple text wrapping:**
+```swift
+// Long text will wrap to multiple lines
+label.latex = "\\(\\text{The quadratic formula is used to solve equations of the form } ax^2 + bx + c = 0\\)"
+label.preferredMaxLayoutWidth = 250
+```
+
+**Simple equation with operators:**
+```swift
+// Long equations can break between operators if too long
+label.latex = "\\(5 + 10 + 15 + 20 + 25 + 30\\)"
+label.preferredMaxLayoutWidth = 150
+// Will wrap: "5 + 10 + 15 + 20 +"
+//            "25 + 30"
+```
+
+**Mixed text and math:**
+```swift
+// Text wraps but math expressions stay intact
+label.latex = "\\(\\text{Result: } 5 \\times 1000 = 5000 \\text{ meters}\\)"
+label.preferredMaxLayoutWidth = 200
+// Will wrap at spaces between text and operators
+```
+
+**Multiple lines in SwiftUI:**
+```swift
+ScrollView {
+    VStack(alignment: .leading, spacing: 12) {
+        ForEach(steps) { step in
+            MathView(
+                equation: step.description,
+                fontSize: 17,
+                labelMode: .text
+            )
+        }
+    }
+    .padding()
+}
+// Each MathView will automatically wrap based on available width
+```
+
 ### Included Features
 This is a list of formula types that the library currently supports:
 

Sources/SwiftMath/MathRender/MTMathUILabel.swift

@@ -179,7 +179,19 @@ public class MTMathUILabel : MTView {
     /** The internal display of the MTMathUILabel. This is for advanced use only. */
     public var displayList: MTMathListDisplay? { _displayList }
     private var _displayList:MTMathListDisplay?
-    
+
+    /** The preferred maximum width (in points) for a multiline label.
+     Set this property to enable line wrapping based on available width. */
+    public var preferredMaxLayoutWidth: CGFloat {
+        set {
+            _preferredMaxLayoutWidth = newValue
+            self.invalidateIntrinsicContentSize()
+            self.setNeedsLayout()
+        }
+        get { _preferredMaxLayoutWidth }
+    }
+    private var _preferredMaxLayoutWidth: CGFloat = 0
+
     public var currentStyle:MTLineStyle {
         switch _labelMode {
             case .display: return .display
@@ -241,8 +253,12 @@ public class MTMathUILabel : MTView {
     
     func _layoutSubviews() {
         if _mathList != nil {
+            // Use the effective width for layout
+            let effectiveWidth = _preferredMaxLayoutWidth > 0 ? _preferredMaxLayoutWidth : bounds.size.width
+            let availableWidth = effectiveWidth - contentInsets.left - contentInsets.right
+
             // print("Pre list = \(_mathList!)")
-            _displayList = MTTypesetter.createLineForMathList(_mathList, font: font, style: currentStyle)
+            _displayList = MTTypesetter.createLineForMathList(_mathList, font: font, style: currentStyle, maxWidth: availableWidth)
             _displayList!.textColor = textColor
             // print("Post list = \(_mathList!)")
             var textX = CGFloat(0)
@@ -252,7 +268,7 @@ public class MTMathUILabel : MTView {
                 case .right:  textX = bounds.size.width - _displayList!.width - contentInsets.right
             }
             let availableHeight = bounds.size.height - contentInsets.bottom - contentInsets.top
-            
+
             // center things vertically
             var height = _displayList!.ascent + _displayList!.descent
             if height < fontSize/2 {
@@ -268,19 +284,47 @@ public class MTMathUILabel : MTView {
     }
     
     func _sizeThatFits(_ size:CGSize) -> CGSize {
-        guard _mathList != nil else { return size }
-        var size = size
+        guard _mathList != nil else {
+            // No content - return no-intrinsic-size marker
+            return CGSize(width: -1, height: -1)
+        }
+
+        // Determine the maximum width to use
+        var maxWidth: CGFloat = 0
+        if _preferredMaxLayoutWidth > 0 {
+            maxWidth = _preferredMaxLayoutWidth - contentInsets.left - contentInsets.right
+        } else if size.width > 0 {
+            maxWidth = size.width - contentInsets.left - contentInsets.right
+        }
+
         var displayList:MTMathListDisplay? = nil
-        displayList = MTTypesetter.createLineForMathList(_mathList, font: font, style: currentStyle)
-        size.width = displayList!.width + contentInsets.left + contentInsets.right
-        size.height = displayList!.ascent + displayList!.descent + contentInsets.top + contentInsets.bottom
-        return size
+        displayList = MTTypesetter.createLineForMathList(_mathList, font: font, style: currentStyle, maxWidth: maxWidth)
+
+        guard displayList != nil else {
+            // Failed to create display list
+            return CGSize(width: -1, height: -1)
+        }
+
+        let resultWidth = displayList!.width + contentInsets.left + contentInsets.right
+        let resultHeight = displayList!.ascent + displayList!.descent + contentInsets.top + contentInsets.bottom
+        return CGSize(width: resultWidth, height: resultHeight)
     }
-    
+
+    #if os(macOS)
+    public func sizeThatFits(_ size: CGSize) -> CGSize {
+        return _sizeThatFits(size)
+    }
+    #else
+    public override func sizeThatFits(_ size: CGSize) -> CGSize {
+        return _sizeThatFits(size)
+    }
+    #endif
+
 #if os(macOS)
     func setNeedsDisplay() { self.needsDisplay = true }
     func setNeedsLayout() { self.needsLayout = true }
     public override var fittingSize: CGSize { _sizeThatFits(CGSizeZero) }
+    public override var intrinsicContentSize: CGSize { _sizeThatFits(CGSizeZero) }
     override public var isFlipped: Bool { false }
     override public func layout() {
         self._layoutSubviews()

Sources/SwiftMath/MathRender/MTTypesetter.swift

@@ -362,23 +362,40 @@ class MTTypesetter {
     }
     var cramped = false
     var spaced = false
+    var maxWidth: CGFloat = 0  // Maximum width for line breaking, 0 means no constraint
     
     static func createLineForMathList(_ mathList:MTMathList?, font:MTFont?, style:MTLineStyle) -> MTMathListDisplay? {
         let finalizedList = mathList?.finalized
-        // default is not cramped
-        return self.createLineForMathList(finalizedList, font:font, style:style, cramped:false)
+        // default is not cramped, no width constraint
+        return self.createLineForMathList(finalizedList, font:font, style:style, cramped:false, maxWidth: 0)
     }
-    
+
+    static func createLineForMathList(_ mathList:MTMathList?, font:MTFont?, style:MTLineStyle, maxWidth:CGFloat) -> MTMathListDisplay? {
+        let finalizedList = mathList?.finalized
+        // default is not cramped
+        return self.createLineForMathList(finalizedList, font:font, style:style, cramped:false, maxWidth: maxWidth)
+    }
+
     // Internal
     static func createLineForMathList(_ mathList:MTMathList?, font:MTFont?, style:MTLineStyle, cramped:Bool) -> MTMathListDisplay? {
-        return self.createLineForMathList(mathList, font:font, style:style, cramped:cramped, spaced:false)
+        return self.createLineForMathList(mathList, font:font, style:style, cramped:cramped, spaced:false, maxWidth: 0)
     }
-    
+
+    // Internal
+    static func createLineForMathList(_ mathList:MTMathList?, font:MTFont?, style:MTLineStyle, cramped:Bool, maxWidth:CGFloat) -> MTMathListDisplay? {
+        return self.createLineForMathList(mathList, font:font, style:style, cramped:cramped, spaced:false, maxWidth: maxWidth)
+    }
+
     // Internal
     static func createLineForMathList(_ mathList:MTMathList?, font:MTFont?, style:MTLineStyle, cramped:Bool, spaced:Bool) -> MTMathListDisplay? {
+        return self.createLineForMathList(mathList, font:font, style:style, cramped:cramped, spaced:spaced, maxWidth: 0)
+    }
+
+    // Internal
+    static func createLineForMathList(_ mathList:MTMathList?, font:MTFont?, style:MTLineStyle, cramped:Bool, spaced:Bool, maxWidth:CGFloat) -> MTMathListDisplay? {
         assert(font != nil)
         let preprocessedAtoms = self.preprocessMathList(mathList)
-        let typesetter = MTTypesetter(withFont:font, style:style, cramped:cramped, spaced:spaced)
+        let typesetter = MTTypesetter(withFont:font, style:style, cramped:cramped, spaced:spaced, maxWidth: maxWidth)
         typesetter.createDisplayAtoms(preprocessedAtoms)
         let lastAtom = mathList!.atoms.last
         let last = lastAtom?.indexRange ?? NSMakeRange(0, 0)
@@ -387,13 +404,14 @@ class MTTypesetter {
     }
     
     static var placeholderColor: MTColor { MTColor.blue }
-    
-    init(withFont font:MTFont?, style:MTLineStyle, cramped:Bool, spaced:Bool) {
+
+    init(withFont font:MTFont?, style:MTLineStyle, cramped:Bool, spaced:Bool, maxWidth:CGFloat = 0) {
         self.font = font
         self.displayAtoms = [MTDisplay]()
         self.currentPosition = CGPoint.zero
         self.cramped = cramped
         self.spaced = spaced
+        self.maxWidth = maxWidth
         self.currentLine = NSMutableAttributedString()
         self.currentAtoms = [MTMathAtom]()
         self.style = style
@@ -662,22 +680,78 @@ class MTTypesetter {
                     }
                     
                 case .accent:
-                    // stash the existing layout
-                    if currentLine.length > 0 {
-                        self.addDisplayLine()
-                    }
-                    // Accent is considered as Ord in rule 16.
-                    self.addInterElementSpace(prevNode, currentType:.ordinary)
-                    atom.type = .ordinary;
-                    
-                    let accent = atom as! MTAccent?
-                    let display = self.makeAccent(accent)
-                    displayAtoms.append(display!)
-                    currentPosition.x += display!.width;
-                    
-                    // add super scripts || subscripts
-                    if atom.subScript != nil || atom.superScript != nil {
-                        self.makeScripts(atom, display:display, index:UInt(atom.indexRange.location), delta:0)
+                    if maxWidth > 0 {
+                        // When line wrapping is enabled, render the accent properly but inline
+                        // to avoid premature line flushing
+
+                        let accent = atom as! MTAccent
+
+                        // Get the base character from innerList
+                        var baseChar = ""
+                        if let innerList = accent.innerList, !innerList.atoms.isEmpty {
+                            // Convert innerList to string
+                            baseChar = MTMathListBuilder.mathListToString(innerList)
+                        }
+
+                        // Combine base character with accent to create proper composed character
+                        let accentChar = atom.nucleus
+                        let composedString = baseChar + accentChar
+
+                        // Normalize to composed form (NFC) to get proper accented character
+                        let normalizedString = composedString.precomposedStringWithCanonicalMapping
+
+                        // Add inter-element spacing
+                        if prevNode != nil {
+                            let interElementSpace = self.getInterElementSpace(prevNode!.type, right:.ordinary)
+                            if currentLine.length > 0 {
+                                if interElementSpace > 0 {
+                                    currentLine.addAttribute(kCTKernAttributeName as NSAttributedString.Key,
+                                                           value:NSNumber(floatLiteral: interElementSpace),
+                                                           range:currentLine.mutableString.rangeOfComposedCharacterSequence(at: currentLine.length-1))
+                                }
+                            } else {
+                                currentPosition.x += interElementSpace
+                            }
+                        }
+
+                        // Add the properly composed accented character
+                        let current = NSAttributedString(string:normalizedString)
+                        currentLine.append(current)
+
+                        // Check if we should break the line
+                        self.checkAndBreakLine()
+
+                        // Add to atom list
+                        if currentLineIndexRange.location == NSNotFound {
+                            currentLineIndexRange = atom.indexRange
+                        } else {
+                            currentLineIndexRange.length += atom.indexRange.length
+                        }
+                        currentAtoms.append(atom)
+
+                        // Treat accent as ordinary for spacing purposes
+                        atom.type = .ordinary
+                    } else {
+                        // Original behavior when no width constraint
+                        // Check if we need to break the line due to width constraints
+                        self.checkAndBreakLine()
+                        // stash the existing layout
+                        if currentLine.length > 0 {
+                            self.addDisplayLine()
+                        }
+                        // Accent is considered as Ord in rule 16.
+                        self.addInterElementSpace(prevNode, currentType:.ordinary)
+                        atom.type = .ordinary;
+
+                        let accent = atom as! MTAccent?
+                        let display = self.makeAccent(accent)
+                        displayAtoms.append(display!)
+                        currentPosition.x += display!.width;
+
+                        // add super scripts || subscripts
+                        if atom.subScript != nil || atom.superScript != nil {
+                            self.makeScripts(atom, display:display, index:UInt(atom.indexRange.location), delta:0)
+                        }
                     }
                     
                 case .table:
@@ -720,7 +794,57 @@ class MTTypesetter {
                     } else {
                         current = NSAttributedString(string:atom.nucleus)
                     }
+
                     currentLine.append(current!)
+
+                    // Universal line breaking: only for simple atoms (no scripts)
+                    // This works for text, mixed text+math, and simple equations
+                    let isSimpleAtom = (atom.subScript == nil && atom.superScript == nil)
+
+                    if isSimpleAtom && maxWidth > 0 {
+                        // Measure the current line width
+                        let attrString = currentLine.mutableCopy() as! NSMutableAttributedString
+                        attrString.addAttribute(kCTFontAttributeName as NSAttributedString.Key, value:styleFont.ctFont as Any, range:NSMakeRange(0, attrString.length))
+                        let ctLine = CTLineCreateWithAttributedString(attrString)
+                        let lineWidth = CGFloat(CTLineGetTypographicBounds(ctLine, nil, nil, nil))
+
+                        if lineWidth > maxWidth {
+                            // Line is too wide - need to find a break point
+                            let currentText = currentLine.string
+
+                            // Look for the last space before the current position
+                            if let lastSpaceIndex = currentText.lastIndex(of: " ") {
+                                // Split the line at the last space
+                                let spaceOffset = currentText.distance(from: currentText.startIndex, to: lastSpaceIndex)
+
+                                // Create attributed string for the first line (before space)
+                                let firstLine = NSMutableAttributedString(string: String(currentText.prefix(spaceOffset)))
+                                firstLine.addAttribute(kCTFontAttributeName as NSAttributedString.Key, value:styleFont.ctFont as Any, range:NSMakeRange(0, firstLine.length))
+
+                                // Keep track of atoms that belong to the first line
+                                // For simplicity, we'll split atoms at the boundary (this is approximate)
+                                let firstLineAtoms = currentAtoms
+
+                                // Flush the first line
+                                currentLine = firstLine
+                                currentAtoms = firstLineAtoms
+                                self.addDisplayLine()
+
+                                // Move down for new line and reset x position
+                                currentPosition.y -= styleFont.fontSize * 1.5
+                                currentPosition.x = 0
+
+                                // Start the new line with the content after the space
+                                let remainingText = String(currentText.suffix(from: currentText.index(after: lastSpaceIndex)))
+                                currentLine = NSMutableAttributedString(string: remainingText)
+
+                                // Reset atom list for new line
+                                currentAtoms = []
+                                currentLineIndexRange = NSMakeRange(NSNotFound, NSNotFound)
+                            }
+                            // If no space found, let it overflow (better than breaking mid-word)
+                        }
+                    }
                     // add the atom to the current range
                     if currentLineIndexRange.location == NSNotFound {
                         currentLineIndexRange = atom.indexRange
@@ -767,6 +891,52 @@ class MTTypesetter {
         }
     }
     
+    /// Check if the current line exceeds maxWidth and break if needed
+    func checkAndBreakLine() {
+        guard maxWidth > 0 && currentLine.length > 0 else { return }
+
+        // Measure the current line width
+        let attrString = currentLine.mutableCopy() as! NSMutableAttributedString
+        attrString.addAttribute(kCTFontAttributeName as NSAttributedString.Key, value:styleFont.ctFont as Any, range:NSMakeRange(0, attrString.length))
+        let ctLine = CTLineCreateWithAttributedString(attrString)
+        let lineWidth = CGFloat(CTLineGetTypographicBounds(ctLine, nil, nil, nil))
+
+        guard lineWidth > maxWidth else { return }
+
+        // Line is too wide - need to find a break point
+        let currentText = currentLine.string
+
+        // Look for the last space before the current position
+        if let lastSpaceIndex = currentText.lastIndex(of: " ") {
+            // Split the line at the last space
+            let spaceOffset = currentText.distance(from: currentText.startIndex, to: lastSpaceIndex)
+
+            // Create attributed string for the first line (before space)
+            let firstLine = NSMutableAttributedString(string: String(currentText.prefix(spaceOffset)))
+            firstLine.addAttribute(kCTFontAttributeName as NSAttributedString.Key, value:styleFont.ctFont as Any, range:NSMakeRange(0, firstLine.length))
+
+            // Keep track of atoms that belong to the first line
+            let firstLineAtoms = currentAtoms
+
+            // Flush the first line
+            currentLine = firstLine
+            currentAtoms = firstLineAtoms
+            self.addDisplayLine()
+
+            // Move down for new line and reset x position
+            currentPosition.y -= styleFont.fontSize * 1.5
+            currentPosition.x = 0
+
+            // Start the new line with the content after the space
+            let remainingText = String(currentText.suffix(from: currentText.index(after: lastSpaceIndex)))
+            currentLine = NSMutableAttributedString(string: remainingText)
+
+            // Reset atom list for new line
+            currentAtoms = []
+            currentLineIndexRange = NSMakeRange(NSNotFound, NSNotFound)
+        }
+    }
+
     @discardableResult
     func addDisplayLine() -> MTCTLineDisplay? {
         // add the font

Tests/SwiftMathTests/MTMathUILabelLineWrappingTests.swift

@@ -0,0 +1,194 @@
+//
+//  MTMathUILabelLineWrappingTests.swift
+//  SwiftMathTests
+//
+//  Tests for line wrapping functionality in MTMathUILabel
+//
+
+import XCTest
+@testable import SwiftMath
+
+class MTMathUILabelLineWrappingTests: XCTestCase {
+
+    func testBasicIntrinsicContentSize() {
+        let label = MTMathUILabel()
+        label.latex = "\\(x + y\\)"
+        label.font = MTFontManager.fontManager.defaultFont
+
+        // Debug: check if parsing worked
+        XCTAssertNotNil(label.mathList, "Math list should not be nil")
+        XCTAssertNil(label.error, "Should have no parsing error, got: \(String(describing: label.error))")
+        XCTAssertNotNil(label.font, "Font should not be nil")
+
+        let size = label.intrinsicContentSize
+
+        XCTAssertGreaterThan(size.width, 0, "Width should be greater than 0, got \(size.width)")
+        XCTAssertGreaterThan(size.height, 0, "Height should be greater than 0, got \(size.height)")
+    }
+
+    func testTextModeIntrinsicContentSize() {
+        let label = MTMathUILabel()
+        label.latex = "\\(\\text{Hello World}\\)"
+        label.font = MTFontManager.fontManager.defaultFont
+        label.labelMode = .text
+
+        let size = label.intrinsicContentSize
+
+        XCTAssertGreaterThan(size.width, 0, "Width should be greater than 0, got \(size.width)")
+        XCTAssertGreaterThan(size.height, 0, "Height should be greater than 0, got \(size.height)")
+    }
+
+    func testLongTextIntrinsicContentSize() {
+        let label = MTMathUILabel()
+        label.latex = "\\(\\text{Rappelons la conversion : 1 km équivaut à 1000 m.}\\)"
+        label.font = MTFontManager.fontManager.defaultFont
+        label.labelMode = .text
+
+        let size = label.intrinsicContentSize
+
+        XCTAssertGreaterThan(size.width, 0, "Width should be greater than 0, got \(size.width)")
+        XCTAssertGreaterThan(size.height, 0, "Height should be greater than 0, got \(size.height)")
+    }
+
+    func testSizeThatFitsWithoutConstraint() {
+        let label = MTMathUILabel()
+        label.latex = "\\(\\text{Hello World}\\)"
+        label.font = MTFontManager.fontManager.defaultFont
+
+        let size = label.sizeThatFits(CGSize.zero)
+
+        XCTAssertGreaterThan(size.width, 0, "Width should be greater than 0, got \(size.width)")
+        XCTAssertGreaterThan(size.height, 0, "Height should be greater than 0, got \(size.height)")
+    }
+
+    func testSizeThatFitsWithWidthConstraint() {
+        let label = MTMathUILabel()
+        label.latex = "\\(\\text{Rappelons la conversion : 1 km équivaut à 1000 m.}\\)"
+        label.font = MTFontManager.fontManager.defaultFont
+        label.labelMode = .text
+
+        // Get unconstrained size first
+        let unconstrainedSize = label.sizeThatFits(CGSize.zero)
+        XCTAssertGreaterThan(unconstrainedSize.width, 0, "Unconstrained width should be > 0")
+
+        // Test with width constraint (use 300 since longest word might be ~237pt)
+        let constrainedSize = label.sizeThatFits(CGSize(width: 300, height: CGFloat.greatestFiniteMagnitude))
+
+        XCTAssertGreaterThan(constrainedSize.width, 0, "Constrained width should be greater than 0, got \(constrainedSize.width)")
+        XCTAssertLessThan(constrainedSize.width, unconstrainedSize.width, "Constrained width (\(constrainedSize.width)) should be less than unconstrained (\(unconstrainedSize.width))")
+        XCTAssertGreaterThan(constrainedSize.height, 0, "Constrained height should be greater than 0, got \(constrainedSize.height)")
+
+        // When constrained, height should increase when text wraps
+        XCTAssertGreaterThan(constrainedSize.height, unconstrainedSize.height,
+                            "Constrained height (\(constrainedSize.height)) should be > unconstrained (\(unconstrainedSize.height)) when text wraps")
+    }
+
+    func testPreferredMaxLayoutWidth() {
+        let label = MTMathUILabel()
+        label.latex = "\\(\\text{Rappelons la conversion : 1 km équivaut à 1000 m.}\\)"
+        label.font = MTFontManager.fontManager.defaultFont
+        label.labelMode = .text
+
+        // Get unconstrained size
+        let unconstrainedSize = label.intrinsicContentSize
+
+        // Now set preferred max width (use 300 since longest word might be ~237pt)
+        label.preferredMaxLayoutWidth = 300
+        let constrainedSize = label.intrinsicContentSize
+
+        XCTAssertGreaterThan(constrainedSize.width, 0, "Width should be greater than 0, got \(constrainedSize.width)")
+        XCTAssertLessThan(constrainedSize.width, unconstrainedSize.width, "Constrained width (\(constrainedSize.width)) should be < unconstrained (\(unconstrainedSize.width))")
+        XCTAssertGreaterThan(constrainedSize.height, unconstrainedSize.height, "Constrained height (\(constrainedSize.height)) should be > unconstrained (\(unconstrainedSize.height)) due to wrapping")
+    }
+
+    func testWordBoundaryBreaking() {
+        let label = MTMathUILabel()
+        label.latex = "\\(\\text{Word1 Word2 Word3 Word4 Word5}\\)"
+        label.font = MTFontManager.fontManager.defaultFont
+        label.labelMode = .text
+        label.preferredMaxLayoutWidth = 150
+
+        let size = label.intrinsicContentSize
+
+        XCTAssertGreaterThan(size.width, 0, "Width should be greater than 0, got \(size.width)")
+        XCTAssertGreaterThan(size.height, 0, "Height should be greater than 0, got \(size.height)")
+
+        // Verify it actually uses the layout
+        label.frame = CGRect(origin: .zero, size: size)
+        #if os(macOS)
+        label.layout()
+        #else
+        label.layoutSubviews()
+        #endif
+
+        XCTAssertNotNil(label.displayList, "Display list should be created")
+    }
+
+    func testEmptyLatex() {
+        let label = MTMathUILabel()
+        label.latex = ""
+        label.font = MTFontManager.fontManager.defaultFont
+
+        let size = label.intrinsicContentSize
+
+        // Empty latex should still return a valid size (might be zero or minimal)
+        XCTAssertGreaterThanOrEqual(size.width, 0, "Width should be >= 0 for empty latex, got \(size.width)")
+        XCTAssertGreaterThanOrEqual(size.height, 0, "Height should be >= 0 for empty latex, got \(size.height)")
+    }
+
+    func testMathAndTextMixed() {
+        let label = MTMathUILabel()
+        label.latex = "\\(\\text{Result: } x^2 + y^2 = z^2\\)"
+        label.font = MTFontManager.fontManager.defaultFont
+        label.labelMode = .text
+
+        let size = label.intrinsicContentSize
+
+        XCTAssertGreaterThan(size.width, 0, "Width should be greater than 0, got \(size.width)")
+        XCTAssertGreaterThan(size.height, 0, "Height should be greater than 0, got \(size.height)")
+    }
+
+    func testDebugSizeThatFitsWithConstraint() {
+        let label = MTMathUILabel()
+        label.latex = "\\(\\text{Word1 Word2 Word3 Word4 Word5}\\)"
+        label.font = MTFontManager.fontManager.defaultFont
+        label.labelMode = .text
+
+        let unconstr = label.sizeThatFits(CGSize.zero)
+        let constr = label.sizeThatFits(CGSize(width: 150, height: 999))
+
+        XCTAssertLessThan(constr.width, unconstr.width, "Constrained (\(constr.width)) should be < unconstrained (\(unconstr.width))")
+        XCTAssertGreaterThan(constr.height, unconstr.height, "Constrained height (\(constr.height)) should be > unconstrained (\(unconstr.height))")
+    }
+
+    func testAccentedCharactersWithLineWrapping() {
+        let label = MTMathUILabel()
+        // French text with accented characters: è, é, à
+        label.latex = "\\(\\text{Rappelons la relation entre kilomètres et mètres.}\\)"
+        label.font = MTFontManager.fontManager.defaultFont
+        label.labelMode = .text
+
+        // Get unconstrained size
+        let unconstrainedSize = label.intrinsicContentSize
+
+        // Set a width constraint that should cause wrapping
+        label.preferredMaxLayoutWidth = 250
+        let constrainedSize = label.intrinsicContentSize
+
+        // Verify wrapping occurred
+        XCTAssertGreaterThan(constrainedSize.width, 0, "Width should be > 0")
+        XCTAssertLessThan(constrainedSize.width, unconstrainedSize.width, "Constrained width should be < unconstrained")
+        XCTAssertGreaterThan(constrainedSize.height, unconstrainedSize.height, "Height should increase when wrapped")
+
+        // Verify the label can render without errors
+        label.frame = CGRect(origin: .zero, size: constrainedSize)
+        #if os(macOS)
+        label.layout()
+        #else
+        label.layoutSubviews()
+        #endif
+
+        XCTAssertNotNil(label.displayList, "Display list should be created")
+        XCTAssertNil(label.error, "Should have no rendering error")
+    }
+}