Basic file opening and display. Off-by-one bug skipping first line, though

deno.jsonc

@@ -3,7 +3,7 @@
 		"include": ["src/"],
 		"rules": {
 			"tags": ["recommended"],
-			"exclude": ["no-explicit-any"]
+			"exclude": ["no-explicit-any", "no-inferrable-types"]
 		}
 	},
 	"fmt": {

justfile

@@ -34,8 +34,8 @@ bun-test:
 	bun test --coverage
 
 # Run with bun
-bun-run:
-	bun run ./src/scroll.ts
+bun-run file="":
+	bun run ./src/scroll.ts {{file}}
 
 ########################################################################################################################
 # Deno-specific commands
@@ -56,5 +56,5 @@ deno-coverage:
 	deno coverage --unstable-ffi .deno-cover
 
 # Run with deno
-deno-run:
-	deno run --allow-all --allow-ffi --deny-net --deny-hrtime --unstable ./src/scroll.ts
+deno-run file="":
+	deno run --allow-all --allow-ffi --deny-net --deny-hrtime --unstable ./src/scroll.ts {{file}}

src/bun/file_io.ts

@@ -8,7 +8,7 @@ const BunFileIO: IFIO = {
 		return await file.text();
 	},
 	openFileSync: (path: string): string => {
-		return readFileSync(path);
+		return readFileSync(path).toString();
 	},
 };
 

src/bun/terminal_io.ts

@@ -5,7 +5,10 @@ import { ITerminal, ITerminalSize } from '../common/mod.ts';
 import Ansi from '../common/ansi.ts';
 
 const BunTerminalIO: ITerminal = {
-	argv: Bun.argv,
+	// Deno only returns arguments passed to the script, so
+	// remove the bun runtime executable, and entry script arguments
+	// to have consistent argument lists
+	argv: (Bun.argv.length > 2) ? Bun.argv.slice(2) : [],
 	inputLoop: async function* inputLoop() {
 		for await (const chunk of Bun.stdin.stream()) {
 			yield chunk;

src/common/buffer.ts

@@ -1,4 +1,4 @@
-import { strlen } from './utils.ts';
+import { strlen, truncate } from './utils.ts';
 import { getRuntime } from './runtime.ts';
 
 class Buffer {
@@ -7,12 +7,12 @@ class Buffer {
 	constructor() {
 	}
 
-	public append(s: string): void {
-		this.#b += s;
+	public append(s: string, maxLen?: number): void {
+		this.#b += (maxLen === undefined) ? s : truncate(s, maxLen);
 	}
 
-	public appendLine(s: string): void {
-		this.#b += s + '\r\n';
+	public appendLine(s = ''): void {
+		this.#b += (s ?? '') + '\r\n';
 	}
 
 	public clear(): void {

src/common/document.ts

@@ -1,4 +1,5 @@
 import { chars } from './utils.ts';
+import { getRuntime } from './runtime.ts';
 
 export class Row {
 	chars: string[] = [];
@@ -27,23 +28,36 @@ export class Document {
 		return new Document();
 	}
 
-	public static open(_filename: string): Document {
-		const doc = new Document();
-		const line = 'Hello, World!';
-		const row = new Row(line);
-
-		doc.#rows.push(row);
-
-		return doc;
+	public isEmpty(): boolean {
+		return this.#rows.length === 0;
 	}
 
-	public getRow(i: number): Row | null {
+	public async open(filename: string): Promise<Document> {
+		const { file } = await getRuntime();
+
+		// Clear any existing rows
+		if (!this.isEmpty()) {
+			this.#rows = [];
+		}
+
+		const rawFile = await file.openFile(filename);
+		rawFile.split(/\r?\n/)
+			.forEach((row) => this.appendRow(row));
+
+		return this;
+	}
+
+	public row(i: number): Row | null {
 		if (this.#rows[i] !== undefined) {
 			return this.#rows[i];
 		}
 
 		return null;
 	}
+
+	protected appendRow(s: string): void {
+		this.#rows.push(new Row(s));
+	}
 }
 
 export default Document;

src/common/editor.ts

@@ -1,23 +1,45 @@
 import Ansi, { KeyCommand } from './ansi.ts';
 import Buffer from './buffer.ts';
 import Document from './document.ts';
-import { ctrl_key, IPoint, ITerminalSize, truncate, VERSION } from './mod.ts';
+import { IPoint, ITerminalSize, VERSION } from './mod.ts';
+import { ctrl_key } from './utils.ts';
 
 export class Editor {
+	/**
+	 * The output buffer for the terminal
+	 * @private
+	 */
 	#buffer: Buffer;
+	/**
+	 * The size of the screen in rows/columns
+	 * @private
+	 */
 	#screen: ITerminalSize;
+	/**
+	 * The current location of the mouse cursor
+	 * @private
+	 */
 	#cursor: IPoint;
+	/**
+	 * The document being edited
+	 * @private
+	 */
 	#document: Document;
-	constructor(terminalSize: ITerminalSize, args: string[]) {
+	constructor(terminalSize: ITerminalSize) {
 		this.#buffer = new Buffer();
 		this.#screen = terminalSize;
 		this.#cursor = {
 			x: 0,
 			y: 0,
 		};
-		this.#document = (args.length >= 2)
-			? Document.open(args[1])
-			: Document.empty();
+
+		this.#document = Document.empty();
+	}
+
+	public async open(filename: string): Promise<Editor> {
+		await this.#document.open(filename);
+
+		return this;
 	}
 
 	// --------------------------------------------------------------------------
@@ -120,7 +142,7 @@ export class Editor {
 
 	private drawRows(): void {
 		for (let y = 0; y < this.#screen.rows; y++) {
-			if (y >= this.#document.numrows) {
+			if (this.#document.numrows < y) {
 				this.drawPlaceholderRow(y);
 			} else {
 				this.drawFileRow(y);
@@ -128,18 +150,19 @@ export class Editor {
 		}
 	}
 
-	private drawFileRow(_y: number): void {
-		const row = this.#document.getRow(0);
+	private drawFileRow(y: number): void {
+		const row = this.#document.row(y);
 		let len = row?.chars.length ?? 0;
 		if (len > this.#screen.cols) {
 			len = this.#screen.cols;
 		}
 
-		this.#buffer.appendLine(truncate(row!.toString(), len));
+		this.#buffer.append(row!.toString(), len);
+		this.#buffer.appendLine(Ansi.ClearLine);
 	}
 
 	private drawPlaceholderRow(y: number): void {
-		if (y === Math.trunc(this.#screen.rows / 2)) {
+		if (y === Math.trunc(this.#screen.rows / 2) && this.#document.isEmpty()) {
 			const message = `Kilo editor -- version ${VERSION}`;
 			const messageLen = (message.length > this.#screen.cols)
 				? this.#screen.cols
@@ -152,14 +175,14 @@ export class Editor {
 				this.#buffer.append(' '.repeat(padding));
 			}
 
-			this.#buffer.append(truncate(message, messageLen));
+			this.#buffer.append(message, messageLen);
 		} else {
 			this.#buffer.append('~');
 		}
 
 		this.#buffer.append(Ansi.ClearLine);
 		if (y < this.#screen.rows - 1) {
-			this.#buffer.appendLine('');
+			this.#buffer.appendLine();
 		}
 	}
 }

src/scroll.ts

@@ -47,7 +47,13 @@ export async function main() {
 	const terminalSize = await term.getTerminalSize();
 
 	// Create the editor itself
-	const editor = new Editor(terminalSize, term.argv);
+	const editor = new Editor(terminalSize);
+	if (term.argv.length > 0) {
+		const filename = term.argv[0];
+		if (filename.trim() !== '') {
+			await editor.open(filename);
+		}
+	}
 	await editor.refreshScreen();
 
 	// The main event loop