visual-test

name	visual-test
description	Visual Test - GPUI Terminal

Headless Visual Test for GPUI Terminal

Automated visual regression testing for the GPUI terminal renderer. Builds the app, runs it headless with test patterns, captures a screenshot, and analyzes the rendering.

Prerequisites

Must be in the nix dev shell (nix develop) which provides cage and grim.

Steps

1. Build the app:

   cargo build -p zremote-gui
   

2. Run headless screenshot capture with the terminal test patterns script:

   ./scripts/headless-screenshot.sh \
     "bash -c './scripts/terminal-test-patterns.sh; sleep 999'" \
     /tmp/zremote-visual-test.png \
     3
   

   If the app needs a server connection, start the local agent first:

   ./scripts/headless-screenshot.sh \
     "./target/debug/zremote-gui --exit-after 8" \
     /tmp/zremote-visual-test.png \
     5
   

3. Read and analyze the screenshot: Use the Read tool on /tmp/zremote-visual-test.png to visually inspect the rendered terminal.

4. Check for rendering issues:

   • ANSI colors render correctly (16 standard + bright colors visible and distinct)
   • 256-color palette shows smooth gradients without banding
   • True color (24-bit) gradients are smooth
   • Text styles (bold, italic, underline, strikethrough) are visually distinct
   • Unicode box drawing characters align properly (no gaps between segments)
   • Monospace verification: all rows of different characters (M, i, W, 1, |) are the same width
   • Block elements and braille characters render without missing glyphs
   • Font rendering is clean (no artifacts, proper anti-aliasing)
   • Cell spacing is uniform (no irregular gaps)

5. Report findings: List any rendering issues found with specific descriptions. If everything looks correct, confirm the visual test passes.

When to run

Run this after any changes to:

• crates/zremote-gui/src/views/terminal_element.rs (rendering)
• crates/zremote-gui/src/views/terminal_panel.rs (state/layout)
• crates/zremote-gui/src/theme.rs (colors)
• Font configuration or cell sizing logic