class Termisu::Testing::Screen

• Termisu::Testing::Screen
• Reference
• Object

Overview

A minimal terminal emulator: feed it the byte stream a Termisu program writes and it maintains a 2D grid of Termisu::Cell plus a cursor, so tests can assert on what's rendered (get_by_text, cursor, #to_s snapshot).

Scope: it decodes the subset Termisu emits (absolute cursor positioning, erase, SGR colors/attrs, printable text with wide-char placement) and recognizes-and-skips the rest (DEC private modes, mouse, kitty, OSC). It is NOT a full VT525 — it does not implement scroll regions, tab stops, or insert mode, which Termisu never emits. The grapheme/width logic reuses Termisu::UnicodeWidth so columns match the program's own cursor tracking.

#feed is incremental and keeps parser state across calls, so PTY reads that split an escape sequence mid-stream are handled correctly.

Defined in:

termisu/testing/screen.cr

Constructors

• .new(cols : Int32, rows : Int32)

Instance Method Summary

• #cell(x : Int32, y : Int32) : Cell

  Cell at (x, y).

• #cols : Int32
• #cursor_visible? : Bool
• #cursor_x : Int32
• #cursor_y : Int32
• #feed(bytes : Bytes) : Nil

  Feed a chunk of output bytes.

• #feed(str : String) : Nil
• #includes?(pattern : String | Regex) : Bool

  True if pattern appears anywhere on screen (row-wise match).

• #locate(pattern : String | Regex) : Tuple(Int32, Int32) | Nil

  First {x, y} where pattern starts, or nil.

• #row_text(y : Int32) : String

  The visible text of row y (continuation cells contribute nothing).

• #rows : Int32
• #to_s(io : IO) : Nil

  Whole screen as text, one row per line (trailing blanks stripped per line).

• #to_styled_s(mask : Array(Regex) = [] of Regex) : String

  A deterministic snapshot capturing the glyph grid AND per-cell style (fg/bg/attr), run-length compressed — richer than glyph-only snapshots, so color/attribute regressions are caught.

Constructor Detail

Instance Method Detail