fix(tui): restore cursorUp start-of-line jump when input is non-empty

Author: 4h9fbZ

packages/tui/src/components/editor.ts

@@ -390,6 +390,10 @@ export class Editor implements Component, Focusable {
 		}
 	}
 
+	private isEditorEmpty(): boolean {
+		return this.state.lines.length === 1 && this.state.lines[0] === "";
+	}
+
 	private isOnFirstVisualLine(): boolean {
 		const visualLines = this.buildVisualLineMap(this.lastWidth);
 		const currentVisualLine = this.findCurrentVisualLine(visualLines);
@@ -803,7 +807,10 @@ export class Editor implements Component, Focusable {
 
 		// Arrow key navigation (with history support)
 		if (kb.matches(data, "tui.editor.cursorUp")) {
-			if (this.isOnFirstVisualLine() && this.history.length > 0) {
+			if (
+				this.isOnFirstVisualLine() &&
+				(this.isEditorEmpty() || this.historyIndex > -1 || this.state.cursorCol === 0)
+			) {
 				this.navigateHistory(-1);
 			} else if (this.isOnFirstVisualLine()) {
 				// Already at top - jump to start of line

packages/tui/test/editor.test.ts

@@ -79,20 +79,24 @@ describe("Editor component", () => {
 			assert.strictEqual(editor.getText(), "first");
 		});
 
-		it("restores draft on Down arrow after browsing history", () => {
+		it("jumps to start before entering history from a non-empty draft", () => {
 			const editor = new Editor(createTestTUI(), defaultEditorTheme);
 
 			editor.addToHistory("prompt");
 			editor.setText("draft");
 			editor.handleInput("\x1b[D");
 			editor.handleInput("\x1b[D");
 
-			editor.handleInput("\x1b[A"); // Up - shows "prompt"
+			editor.handleInput("\x1b[A"); // Up - jumps to start before history browsing
+			assert.strictEqual(editor.getText(), "draft");
+			assert.deepStrictEqual(editor.getCursor(), { line: 0, col: 0 });
+
+			editor.handleInput("\x1b[A"); // Up at start - shows "prompt"
 			assert.strictEqual(editor.getText(), "prompt");
 
 			editor.handleInput("\x1b[B"); // Down - restores draft
 			assert.strictEqual(editor.getText(), "draft");
-			assert.deepStrictEqual(editor.getCursor(), { line: 0, col: 3 });
+			assert.deepStrictEqual(editor.getCursor(), { line: 0, col: 0 });
 		});
 
 		it("navigates forward through history with Down arrow", () => {
@@ -104,6 +108,7 @@ describe("Editor component", () => {
 			editor.setText("draft");
 
 			// Go to oldest
+			editor.handleInput("\x1b[A"); // start of draft
 			editor.handleInput("\x1b[A"); // third
 			editor.handleInput("\x1b[A"); // second
 			editor.handleInput("\x1b[A"); // first