Struct BufferView 

pub struct BufferView<'a, R: StyleResolver> {

    pub buffer: &'a Buffer,
    pub viewport: &'a Viewport,
    pub selection: Option<Selection>,
    pub resolver: &'a R,
    pub cursor_line_bg: Style,
    pub fold_line_bg: Style,
    pub cursor_column_bg: Style,
    pub selection_bg: Style,
    pub cursor_style: Style,
    pub gutter: Option<Gutter>,
    pub search_bg: Style,
    pub signs: &'a [Sign],
    pub conceals: &'a [Conceal],
    pub spans: &'a [Vec<Span>],
    pub search_pattern: Option<&'a Regex>,
    pub non_text_style: Style,
    pub diag_overlays: &'a [DiagOverlay],
    pub colorcolumn_cols: &'a [u16],
    pub colorcolumn_style: Style,
    pub listchars: Option<&'a ListChars>,
    pub indent_guides_enabled: bool,
    pub indent_guide_char: char,
    pub indent_guide_shiftwidth: usize,
    pub indent_guide_fg: Color,
    pub indent_guide_active_fg: Color,
    pub indent_guide_active_col: Option<usize>,
    pub eol_hints: &'a [EolHint],
    pub blame_plan: Option<&'a [BlameRow]>,
}

Render-time wrapper around &Buffer that carries the optional Selection + a StyleResolver. Created per draw, dropped when the frame is done — cheap, holds only refs.

0.0.34 (Patch C-δ.1): added the viewport field. The viewport previously lived on the buffer itself; with the relocation to the engine Host, the renderer takes a borrow per draw.

0.0.37: added the spans and search_pattern fields. Per-row syntax spans + the active / regex used to live on the buffer (Buffer::spans / Buffer::search_pattern); both moved out per step 3 of DESIGN_33_METHOD_CLASSIFICATION.md. The host now feeds each into the view per draw — populated from Editor::buffer_spans() and Editor::search_state().pattern.

Fields

buffer: &'a Buffer

viewport: &'a Viewport

Viewport snapshot the host published this frame. Owned by the engine Host; the renderer borrows for the duration of the draw.

selection: Option<Selection>

resolver: &'a R

cursor_line_bg: Style

Bg painted across the cursor row (vim’s cursorline). Pass Style::default() to disable.

fold_line_bg: Style

Bg painted across a closed fold’s header row — brighter than cursor_line_bg so a collapsed fold is visually distinct. Style::default() to disable.

cursor_column_bg: Style

Bg painted down the cursor column (vim’s cursorcolumn). Pass Style::default() to disable.

selection_bg: Style

Bg painted under selected cells. Composed over syntax fg.

cursor_style: Style

Style for the cursor cell. REVERSED is the conventional choice; works against any theme.

gutter: Option<Gutter>

Optional left-side line-number gutter. width includes the trailing space separating the number from text. Pass None to disable. Numbers are 1-based, right-aligned.

search_bg: Style

Bg painted under cells covered by an active / search match. Style::default() to disable.

signs: &'a [Sign]

Per-row gutter signs (LSP diagnostic dots, git diff markers, …). Painted into the leftmost gutter column after the line number, so they overwrite the leading space tui-style gutters reserve. Highest-priority sign per row wins.

conceals: &'a [Conceal]

Per-row substitutions applied at render time. Each conceal hides the byte range [start_byte, end_byte) and paints replacement in its place. Empty slice = no conceals.

spans: &'a [Vec<Span>]

Per-row syntax spans the host has computed for this frame. spans[row] carries the styled byte ranges for that row; rows beyond spans.len() get no syntax styling. Pass &[] for hosts without syntax integration.

0.0.37: lifted out of Buffer per step 3 of DESIGN_33_METHOD_CLASSIFICATION.md. The engine populates this via Editor::buffer_spans().

search_pattern: Option<&'a Regex>

Active / search regex, if any. The renderer paints Self::search_bg under cells that match. Pass None to disable hlsearch.

0.0.37: lifted out of Buffer (was Buffer::search_pattern) per step 3 of DESIGN_33_METHOD_CLASSIFICATION.md. The engine publishes the pattern via Editor::search_state().pattern.

non_text_style: Style

Style for the ~ tilde marker painted on screen rows that are past the last buffer line (vim’s NonText highlight group). Pass Style::default() to use terminal defaults.

The gutter on those rows is painted blank; the ~ appears at the leftmost text column. Rows within the buffer are unaffected.

diag_overlays: &'a [DiagOverlay]

Diagnostic overlays (LSP inline highlights). Applied in a post-paint pass after every row is drawn so they layer on top of syntax and selection colours without a second layout traversal. Pass &[] to disable. Added in 0.5.0.

colorcolumn_cols: &'a [u16]

1-based column indices for vertical rulers (vim’s colorcolumn). The renderer paints colorcolumn_style on those text-area cells beneath syntax highlights. Pass &[] to disable.

colorcolumn_style: Style

Background style applied to cells at a colorcolumn position. Ignored when colorcolumn_cols is empty.

listchars: Option<&'a ListChars>

When Some, invisibles rendering is active. The hjkl_buffer::ListChars value controls which glyphs substitute whitespace characters. Matches vim’s :set list + :set listchars. Pass None to disable.

indent_guides_enabled: bool

When true, paint thin vertical indent guide characters at every shiftwidth-aligned leading-whitespace column on each row. Only active in Wrap::None mode. Pass false to disable.

indent_guide_char: char

Character to paint as the indent guide. Typically '│'.

indent_guide_shiftwidth: usize

Number of leading visual columns that qualify as “shiftwidth” per level. Derived from Settings::shiftwidth / Settings::tabstop. The renderer uses this to locate guide columns on each row.

indent_guide_fg: Color

Fg color for inactive indent guide cells.

indent_guide_active_fg: Color

Fg color for the active (cursor’s indent level) guide cell.

indent_guide_active_col: Option<usize>

Visual column of the active indent guide, if any. Computed from the cursor row’s leading whitespace and indent_guide_shiftwidth. None when the cursor sits on a non-indented or empty row.

eol_hints: &'a [EolHint]

End-of-line virtual-text hints (e.g. inline git blame). Painted after each row’s real text in a post-pass. Empty slice = none. Added for #202.

blame_plan: Option<&'a [BlameRow]>

Boxed-blame layout. When Some, the renderer draws exactly this sequence of screen rows (top-to-bottom) instead of deriving rows from top_row: Content(doc_row) paints that buffer row, BorderTop/ BorderBottom paint a box rule. The host (render level) builds the plan — the engine’s cursor/scroll stays the source of truth. Wrap::None only. None = normal rendering.

Trait Implementations

impl<R: StyleResolver> Widget for BufferView<'_, R>

fn render(self, area: Rect, term_buf: &mut TermBuffer)

Draws the current state of the widget in the given buffer. That is the only method required to implement a custom widget.