Fix prompt in deno, but break in bun :(

src/bun/terminal_io.ts

@@ -16,8 +16,10 @@ const BunTerminalIO: ITerminal = {
 	argv: (Bun.argv.length > 2) ? Bun.argv.slice(2) : [],
 	inputLoop: async function* inputLoop() {
 		for await (const chunk of Bun.stdin.stream()) {
-			yield readKey(chunk);
+			yield chunk;
 		}
+
+		return null;
 	},
 	getTerminalSize: async function getTerminalSize(): Promise<ITerminalSize> {
 		const encoder = new TextEncoder();
@@ -33,28 +35,32 @@ const BunTerminalIO: ITerminal = {
 
 		// Get the first chunk from stdin
 		// The response is \x1b[(rows);(cols)R..
-		for await (const chunk of Bun.stdin.stream()) {
-			const rawCode = (new TextDecoder()).decode(chunk);
-			const res = rawCode.trim().replace(/^.\[([0-9]+;[0-9]+)R$/, '$1');
-			const [srows, scols] = res.split(';');
-			const rows = parseInt(srows, 10) ?? 24;
-			const cols = parseInt(scols, 10) ?? 80;
-
-			// Clear the screen
-			await write(Ansi.ClearScreen + Ansi.ResetCursor);
-
-			return {
-				rows,
-				cols,
-			};
+		const chunk = await BunTerminalIO.readStdinRaw();
+		if (chunk === null) {
+			return defaultTerminalSize;
 		}
 
-		return defaultTerminalSize;
+		const rawCode = (new TextDecoder()).decode(chunk);
+		const res = rawCode.trim().replace(/^.\[([0-9]+;[0-9]+)R$/, '$1');
+		const [srows, scols] = res.split(';');
+		const rows = parseInt(srows, 10) ?? 24;
+		const cols = parseInt(scols, 10) ?? 80;
+
+		// Clear the screen
+		await write(Ansi.ClearScreen + Ansi.ResetCursor);
+
+		return {
+			rows,
+			cols,
+		};
 	},
-	readStdin: async function (): Promise<string> {
-		const gen = BunTerminalIO.inputLoop();
-		const chunk = await gen.next();
-		return chunk.value!;
+	readStdin: async function (): Promise<string | null> {
+		const raw = await BunTerminalIO.readStdinRaw();
+		return readKey(raw ?? new Uint8Array(0));
+	},
+	readStdinRaw: async function (): Promise<Uint8Array | null> {
+		const chunk = await BunTerminalIO.inputLoop().next();
+		return chunk.value ?? null;
 	},
 	writeStdout: async function write(s: string): Promise<void> {
 		const buffer = new TextEncoder().encode(s);

src/common/editor.ts

@@ -7,6 +7,7 @@ import {
 	ITerminalSize,
 	logToFile,
 	Position,
+	readKey,
 	SCROLL_QUIT_TIMES,
 	SCROLL_VERSION,
 } from './mod.ts';
@@ -229,23 +230,35 @@ class Editor {
 
 		let res = '';
 
-		while (true) {
+		outer: while (true) {
 			this.setStatusMessage(`${p}${res}`);
 			await this.refreshScreen();
-			const char = await term.readStdin();
-			// End the prompt
-			if (char === KeyCommand.Enter) {
-				this.setStatusMessage('');
-				if (res.length === 0) {
-					return null;
+			for await (const chunk of term.inputLoop()) {
+				const char = readKey(chunk);
+				if (char === null) {
+					continue;
 				}
 
-				return res;
-			}
+				// End the prompt
+				if (char === KeyCommand.Enter) {
+					this.setStatusMessage('');
+					if (res.length === 0) {
+						return null;
+					}
 
-			// Add to the prompt result
-			if (!isControl(char)) {
-				res += char;
+					return res;
+				}
+
+				// Allow backspacing
+				if (char === KeyCommand.Backspace || char === KeyCommand.Delete) {
+					res = truncate(res, res.length - 1);
+					continue outer;
+				}
+
+				// Add to the prompt result
+				if (!isControl(char!)) {
+					res += char;
+				}
 			}
 		}
 	}

src/common/main.ts

@@ -1,4 +1,4 @@
-import { getRuntime } from './runtime.ts';
+import { getRuntime, readKey } from './runtime.ts';
 import { getTermios } from './termios.ts';
 import Editor from './editor.ts';
 
@@ -37,16 +37,21 @@ export async function main() {
 	// Clear the screen
 	await editor.refreshScreen();
 
-	for await (const char of term.inputLoop()) {
-		// Process input
-		const shouldLoop = await editor.processKeyPress(char);
-		if (!shouldLoop) {
-			return 0;
+	while (true) {
+		for await (const char of term.inputLoop()) {
+			const parsed = readKey(char);
+			if (char.length === 0 || parsed.length === 0) {
+				continue;
+			}
+
+			// Process input
+			const shouldLoop = await editor.processKeyPress(parsed);
+			if (!shouldLoop) {
+				return;
+			}
+
+			// Render output
+			await editor.refreshScreen();
 		}
-
-		// Render output
-		await editor.refreshScreen();
 	}
-
-	return -1;
 }

src/common/runtime.ts

@@ -64,14 +64,22 @@ export interface ITerminal {
 	/**
 	 * The generator function returning chunks of input from the stdin stream
 	 */
-	inputLoop(): AsyncGenerator<string, void>;
+	inputLoop(): AsyncGenerator<Uint8Array, null>;
 
 	/**
 	 * Get the size of the terminal
 	 */
 	getTerminalSize(): Promise<ITerminalSize>;
 
-	readStdin(): Promise<string>;
+	/**
+	 * Get the current chunk of input, if it exists
+	 */
+	readStdin(): Promise<string | null>;
+
+	/**
+	 * Get the raw chunk of input
+	 */
+	readStdinRaw(): Promise<Uint8Array | null>;
 
 	/**
 	 * Pipe a string to stdout
@@ -147,6 +155,9 @@ let scrollRuntime: IRuntime | null = null;
  * @param raw - the raw chunk of input
  */
 export function readKey(raw: Uint8Array): string {
+	if (raw.length === 0) {
+		return '';
+	}
 	const parsed = decoder.decode(raw);
 
 	// Return the input if it's unambiguous

src/deno/terminal_io.ts

@@ -2,13 +2,10 @@ import { ITerminal, ITerminalSize, readKey } from '../common/runtime.ts';
 
 const DenoTerminalIO: ITerminal = {
 	argv: Deno.args,
-	/**
-	 * Wrap the runtime-specific hook into stdin
-	 */
-	inputLoop: async function* inputLoop() {
-		for await (const chunk of Deno.stdin.readable) {
-			yield readKey(chunk);
-		}
+	inputLoop: async function* (): AsyncGenerator<Uint8Array, null> {
+		yield await DenoTerminalIO.readStdinRaw() ?? new Uint8Array(0);
+
+		return null;
 	},
 	getTerminalSize: function getSize(): Promise<ITerminalSize> {
 		const size: { rows: number; columns: number } = Deno.consoleSize();
@@ -18,10 +15,16 @@ const DenoTerminalIO: ITerminal = {
 			cols: size.columns,
 		});
 	},
-	readStdin: async function (): Promise<string> {
-		const gen = DenoTerminalIO.inputLoop();
-		const chunk = await gen.next();
-		return chunk.value!;
+	readStdin: async function (): Promise<string | null> {
+		const raw = await DenoTerminalIO.readStdinRaw();
+		return readKey(raw ?? new Uint8Array(0));
+	},
+	readStdinRaw: async function (): Promise<Uint8Array | null> {
+		const reader = Deno.stdin.readable.getReader();
+		const chunk = await reader.read();
+		const res = chunk?.value;
+		reader.releaseLock();
+		return res ?? null;
 	},
 	writeStdout: async function write(s: string): Promise<void> {
 		const buffer: Uint8Array = new TextEncoder().encode(s);