import { spawnSync } from "node:child_process";
/** One half of the terminal: it can be handed to a child process and taken
 *  back. Both `TerminalInput` and `TerminalOutput` are one. */
export type Releasable = {
    release: () => void;
    reclaim: () => void;
};
/** The two halves of the terminal the form owns. */
export type ReleasableTerminal = {
    input: Releasable;
    output: Releasable;
};
export type EditorCommand = {
    command: string;
    args: string[];
};
/** `$EDITOR`, split on spaces so `code --wait` works. A quoted path with a
 *  space in it is not supported. Null when the variable is unset or blank. */
export declare function editorCommand(env: Record<string, string | undefined>): EditorCommand | null;
/** Run `fn` with the terminal handed to a child process, then take it back.
 *  The output leaves the alternate screen and stops answering the signals
 *  the child's keys send; the input stops reading stdin, so the child is the
 *  only reader of the terminal while it runs. */
export declare function withTerminalReleased<T>(terminal: ReleasableTerminal, fn: () => T): T;
/** Open `text` in the editor and return what was saved, or null when the
 *  editor exited with a non-zero status. Editors end a file with a newline;
 *  that one is dropped, so the value matches what typing it in place gives. */
export declare function openInEditor(text: string, editor: EditorCommand, terminal: ReleasableTerminal, spawn?: typeof spawnSync): string | null;