Web playground

Local development

• Run trunk serve and open http://127.0.0.1:8080/.
• GitHub Pages builds pass --public-url /NEPL-g2/ so the published site resolves assets under that prefix.
• If you set --public-url to a subpath (e.g. /web/dist/), trunk serve will also expect that base path. Open http://127.0.0.1:8080/web/dist/ or pass --serve-base / --ws-base / to serve from root while keeping asset URLs under the subpath.

Panel workspace

The playground now uses a split-tree workspace instead of the old fixed three-pane layout.

• The root layout starts with Explorer | (Editor / Terminal).
• Each leaf panel owns its own shell, focus state, and, for editor panels, its own tab state.
• Split ratios and focused panel state are saved in localStorage and restored on the next launch.
• Toolbar actions such as Run, Compile, Help, and Save target the focused editor panel.
• File open requests from the explorer also target the focused editor panel, creating or reusing editor state through the workspace manager.
• Drag-and-drop supports moving panel shells across left, right, top, and bottom drop zones.
• Editor tabs can be dragged onto another editor panel to merge there, or dropped on a panel edge to create a new split and move the tab into it.
• Explorer files can be dragged onto an editor panel to open there, or dropped on a panel edge to create a new editor split and open the file there.
• Dragging onto an editor panel's tab bar is treated as tab attachment, not as split creation.
• Center-drop merges for editor panels preserve tab snapshots instead of re-reading from VFS.
• Tab switching is treated as a full-document replace, so syntax highlighting does not reuse incremental payloads across unrelated files.
• Each editor panel owns its own language provider instance; analysis state is not shared across panels.
• Explorer duplication is intentionally blocked, and the last explorer or last editor panel cannot be closed.
• Editor panels keep zoom per active tab, and terminal panels keep zoom per panel.
• Zoom controls are Ctrl+Wheel, Ctrl++, Ctrl+-, Ctrl+0, and two-finger pinch on touch devices. The current zoom is shown as a temporary badge overlay in the panel.

Terminal features

The embedded terminal can:

• run: compile the current editor source to WASM and execute it in the browser.
• test: compile and execute stdlib tests (from stdlib/tests).
• clear: clear terminal output.

WAT generation is provided by the "WATを生成" button in the editor panel.

Standard input is provided via the terminal stdin textarea. Output is captured
from WASI fd_write and rendered in the terminal pane.

• neplg2 build / neplg2 run and wasmi execution now run in a dedicated web worker, so compile and execution no longer block the workspace UI.
• The worker owns long-running WASI execution and streams stdout/stderr back to the terminal while stdin continues to be accepted from the focused terminal panel.

Notes

• The compiler runs in WebAssembly and uses an in-memory stdlib source map.
• Diagnostics are rendered as text with line/column information.
• The terminal is a browser-only convenience; it does not execute cargo commands.
• Only stdlib imports are available in the browser; local file imports are not supported yet.

Editor redevelopment test path

The playground editor redesign is expected to stay testable without a browser.

• The app entrypoint now creates the editor through the new editor-core browser adapter instead of calling the old global factory directly.
• Build the web TypeScript side first with npm --prefix web run build:ts.
• When the Rust / WASM side changes, run trunk build before CLI verification.
• The formal CLI check is node nodesrc/cli.js -i tests/playground_editor --playground-editor-tests -o json=/tmp/playground-editor-tests.json.
• Inspect the generated JSON summary to confirm case counts, failures, and per-case snapshots.
• The CLI suite now covers keyboard/state fixtures, pure text editing, left-right and vertical cursor movement, Home/End, PageUp/PageDown, and pure analysis fixtures for highlight payloads, problems, hover, definition, and occurrences.
• Workspace-specific headless checks include node nodesrc/playground_workspace_test_runner.js and node nodesrc/playground_tab_transfer_test_runner.js.
• Drag/drop intent checks include node nodesrc/playground_drag_drop_test_runner.js.
• Terminal worker protocol checks include node nodesrc/playground_shell_worker_test_runner.js.
• trunk build is still a hard requirement before commit, but it depends on the trunk binary being available in the environment.