LibWeb: Replace to_px() with to_px_or_zero() in InlineFormattingContext

to_px() usage should be avoided because it might leak saturated
(infinite) values into layout calculations.

Userland/Libraries/LibWeb/Layout/InlineFormattingContext.cpp

@@ -53,10 +53,14 @@ CSSPixels InlineFormattingContext::leftmost_x_offset_at(CSSPixels y) const
     return left_side_floats_limit_to_right - max(CSSPixels(0), box_in_root_rect.x());
 }
 
-CSSPixels InlineFormattingContext::available_space_for_line(CSSPixels y) const
+AvailableSize InlineFormattingContext::available_space_for_line(CSSPixels y) const
 {
     auto intrusions = parent().intrusion_by_floats_into_box(containing_block(), y);
-    return m_available_space->width.to_px() - (intrusions.left + intrusions.right);
+    if (m_available_space->width.is_definite()) {
+        return AvailableSize::make_definite(m_available_space->width.to_px_or_zero() - (intrusions.left + intrusions.right));
+    } else {
+        return m_available_space->width;
+    }
 }
 
 CSSPixels InlineFormattingContext::automatic_content_width() const
@@ -130,15 +134,19 @@ void InlineFormattingContext::dimension_box_on_line(Box const& box, LayoutMode l
     if (should_treat_width_as_auto(box, *m_available_space)) {
         auto result = calculate_shrink_to_fit_widths(box);
 
-        auto available_width = m_available_space->width.to_px()
+        if (m_available_space->width.is_definite()) {
-            - box_state.margin_left
+            auto available_width = m_available_space->width.to_px_or_zero()
-            - box_state.border_left
+                - box_state.margin_left
-            - box_state.padding_left
+                - box_state.border_left
-            - box_state.padding_right
+                - box_state.padding_left
-            - box_state.border_right
+                - box_state.padding_right
-            - box_state.margin_right;
+                - box_state.border_right
+                - box_state.margin_right;
 
-        unconstrained_width = min(max(result.preferred_minimum_width, available_width), result.preferred_width);
+            unconstrained_width = min(max(result.preferred_minimum_width, available_width), result.preferred_width);
+        } else {
+            unconstrained_width = result.preferred_width;
+        }
     } else {
         if (width_value.contains_percentage() && !m_available_space->width.is_definite()) {
             // NOTE: We can't resolve percentages yet. We'll have to wait until after inner layout.
@@ -195,7 +203,7 @@ void InlineFormattingContext::apply_justification_to_fragments(CSS::TextJustify
     if (is_last_line || line_box.m_has_forced_break)
         return;
 
-    CSSPixels excess_horizontal_space = line_box.original_available_width() - line_box.width();
+    CSSPixels excess_horizontal_space = line_box.original_available_width().to_px_or_zero() - line_box.width();
     CSSPixels excess_horizontal_space_including_whitespace = excess_horizontal_space;
     size_t whitespace_count = 0;
     for (auto& fragment : line_box.fragments()) {
@@ -343,7 +351,7 @@ bool InlineFormattingContext::can_fit_new_line_at_y(CSSPixels y) const
     };
 
     auto right_edge = [this](auto& space) -> CSSPixels {
-        return m_available_space->width.to_px() - space.right;
+        return m_available_space->width.to_px_or_zero() - space.right;
     };
 
     auto top_left_edge = left_edge(top_intrusions);

Userland/Libraries/LibWeb/Layout/InlineFormattingContext.h

@@ -30,7 +30,7 @@ public:
     void dimension_box_on_line(Box const&, LayoutMode);
 
     CSSPixels leftmost_x_offset_at(CSSPixels y) const;
-    CSSPixels available_space_for_line(CSSPixels y) const;
+    AvailableSize available_space_for_line(CSSPixels y) const;
     bool any_floats_intrude_at_y(CSSPixels y) const;
     bool can_fit_new_line_at_y(CSSPixels y) const;
 

Userland/Libraries/LibWeb/Layout/InlineLevelIterator.cpp

@@ -121,7 +121,7 @@ void InlineLevelIterator::skip_to_next()
     compute_next();
 }
 
-Optional<InlineLevelIterator::Item> InlineLevelIterator::next(CSSPixels available_width)
+Optional<InlineLevelIterator::Item> InlineLevelIterator::next(AvailableSize available_width)
 {
     if (!m_current_node)
         return {};

Userland/Libraries/LibWeb/Layout/InlineLevelIterator.h

@@ -51,7 +51,7 @@ public:
 
     InlineLevelIterator(Layout::InlineFormattingContext&, LayoutState&, Layout::BlockContainer const&, LayoutMode);
 
-    Optional<Item> next(CSSPixels available_width);
+    Optional<Item> next(AvailableSize available_width);
 
 private:
     void skip_to_next();

Userland/Libraries/LibWeb/Layout/LineBox.h

@@ -30,7 +30,7 @@ public:
     bool is_empty_or_ends_in_whitespace() const;
     bool is_empty() const { return m_fragments.is_empty() && !m_has_break; }
 
-    CSSPixels original_available_width() const { return m_original_available_width; }
+    AvailableSize original_available_width() const { return m_original_available_width; }
 
     CSSPixelRect const& absolute_rect() const { return m_absolute_rect; }
     void set_absolute_rect(CSSPixelRect const& rect) { m_absolute_rect = rect; }
@@ -49,7 +49,7 @@ private:
     CSSPixels m_baseline { 0 };
 
     // The amount of available width that was originally available when creating this line box. Used for text justification.
-    CSSPixels m_original_available_width { 0 };
+    AvailableSize m_original_available_width { AvailableSize::make_indefinite() };
 
     bool m_has_break { false };
     bool m_has_forced_break { false };

Userland/Libraries/LibWeb/Layout/LineBuilder.cpp

@@ -136,7 +136,7 @@ CSSPixels LineBuilder::y_for_float_to_be_inserted_here(Box const& box)
 
 bool LineBuilder::should_break(CSSPixels next_item_width)
 {
-    if (!isfinite(m_available_width_for_current_line.to_double()))
+    if (m_available_width_for_current_line.is_max_content())
         return false;
 
     auto const& line_boxes = m_containing_block_state.line_boxes;
@@ -169,7 +169,7 @@ void LineBuilder::update_last_line()
     CSSPixels x_offset_bottom = m_context.leftmost_x_offset_at(m_current_y + current_line_height - 1);
     CSSPixels x_offset = max(x_offset_top, x_offset_bottom);
 
-    CSSPixels excess_horizontal_space = m_available_width_for_current_line - line_box.width();
+    CSSPixels excess_horizontal_space = m_available_width_for_current_line.to_px_or_zero() - line_box.width();
 
     // If (after justification, if any) the inline contents of a line box are too long to fit within it,
     // then the contents are start-aligned: any content that doesn't fit overflows the line box’s end edge.

Userland/Libraries/LibWeb/Layout/LineBuilder.h

@@ -37,7 +37,7 @@ public:
         return false;
     }
 
-    CSSPixels available_width_for_current_line() const { return m_available_width_for_current_line; }
+    AvailableSize available_width_for_current_line() const { return m_available_width_for_current_line; }
 
     void update_last_line();
 
@@ -61,7 +61,7 @@ private:
     InlineFormattingContext& m_context;
     LayoutState& m_layout_state;
     LayoutState::UsedValues& m_containing_block_state;
-    CSSPixels m_available_width_for_current_line { 0 };
+    AvailableSize m_available_width_for_current_line { AvailableSize::make_indefinite() };
     CSSPixels m_current_y { 0 };
     CSSPixels m_max_height_on_current_line { 0 };
     CSSPixels m_text_indent { 0 };