@sandlada/opencode-multiplelines

A plugin for OpenCode TUI v2 only (V1 is completely unsupported). It does exactly one thing: adds a boolean setting named Multiple Lines (on/off, OpenCode TUI uses on/off for on/off).

• Off (default): keeps OpenCode's default behavior — in the chat input, Enter sends; newlines use Shift+Enter / Ctrl+Enter / Alt+Enter / Ctrl+J.
• On: Enter inserts a newline; the original newline keys (Shift+Enter / Ctrl+Enter / Alt+Enter / Ctrl+J) send the prompt.

The setting is persistent (survives restarts, synced across TUI instances) and only affects the chat input: Enter inside dialogs, autocomplete popups, queued prompts, etc. is untouched.

Install

This package ships a TUI entrypoint (./tui) plus a no-op server entrypoint (. / ./server) so that opencode plugin add can install it; it only supports OpenCode v2 (engines.opencode requires >=2.0.0). V1 silently ignores it.

Option 1: opencode CLI (recommended)

opencode plugin add @sandlada/opencode-multiplelines

This automatically writes the package into the global plugins array of ~/.config/opencode/cli.json (TUI-only plugins belong in cli.json, not opencode.json(c)) and installs dependencies.

Option 2: manual configuration

Edit ~/.config/opencode/cli.json directly:

{
  "$schema": "https://opencode.ai/v2/cli.json",
  "plugins": ["@sandlada/opencode-multiplelines"]
}

Local development

{
  "$schema": "https://opencode.ai/v2/cli.json",
  "plugins": ["E:\\projects\\sandlada\\opencode-multiplelines"]
}

Or override temporarily with OPENCODE_CLI_CONFIG_CONTENT:

OPENCODE_CLI_CONFIG_CONTENT='{"plugins":["E:\\projects\\sandlada\\opencode-multiplelines"]}' opencode

Usage

Open the Multiple Lines setting, two ways:

1. Press Ctrl+P, run the Multiple Lines command, then pick on / off in the dialog;
2. Type a slash command in the input:
   • /multiple-lines — opens the dialog above;
   • /multiple-lines on — turn on;
   • /multiple-lines off — turn off;
   • /multiple-lines toggle — flip directly.

Each change shows a Multiple Lines: on/off toast. The current value is stored in plugin storage (settings), default off.

You can also seed the initial value via plugin options in cli.json (only the first time, when no storage file exists; afterward storage wins):

{
  "plugins": [
    {
      "package": "@sandlada/opencode-multiplelines",
      "options": { "multipleLines": true }
    }
  ]
}

How it works

Two keymap layers are registered:

• global command layer: provides the setting command above;
• base swap layer (priority: 100, above the host managed-textarea layer's default 0), enabled bound to the setting:
  • When on, return dispatches input.newline; shift+return / ctrl+return / alt+return / ctrl+j dispatch input.submit;
  • The run checks that the focused editor is a multiline Textarea (excludes single-line Input); otherwise it returns false so the keystroke continues to its normal handler;
  • The swap layer only activates in base mode; modal/autocomplete modes keep their own bindings, so dialog Enter is never mis-swapped.

Note: this plugin targets OpenCode v2's default keybinds (input.submit = return, input.newline = shift+return,ctrl+return,alt+return,ctrl+j). If you override those two keybinds in cli.json, the plugin still intercepts the default keys listed above; adapt the extra keys in your own keybind config.

Development & verification

pnpm install
pnpm typecheck   # tsc --noEmit
pnpm test        # bun test (pure-logic + mock-context integration tests)
pnpm run pack:dry-run

Coverage: setting title, on/off parsing, slash-command input, options initial value, multiline-vs-single-line focus, on/off swap behavior and fallback.

Layout

package.json     # npm plugin manifest (exports "./tui", v2 only)
src/tui.ts       # plugin entry (Plugin.define)
src/settings.ts  # pure logic (title, key names, parsing, fallback detection)
test/*.test.ts   # Bun tests