Feature/move lines up down (#1232)

* Move lines up/down

Author: scambier

plug-api/syscalls/editor.ts

@@ -406,6 +406,14 @@ export function deleteLine(): Promise<void> {
   return syscall("editor.deleteLine");
 }
 
+export function moveLineUp(): Promise<void> {
+  return syscall("editor.moveLineUp");
+}
+
+export function moveLineDown(): Promise<void> {
+  return syscall("editor.moveLineDown");
+}
+
 // Vim-mode specific syscalls
 
 /**

plugs/editor/outline.ts

@@ -5,7 +5,15 @@ export async function moveItemUp() {
   const text = await editor.getText();
 
   try {
-    const currentItemBounds = determineItemBounds(text, cursorPos);
+    let currentItemBounds: ReturnType<typeof determineItemBounds> | undefined;
+    try {
+      currentItemBounds = determineItemBounds(text, cursorPos);
+    } catch {
+      // If `determineItemBounds()` throws, that likely means the cursor is NOT in a bullet list,
+      // so we fall back to `moveLineUp()`
+      editor.moveLineUp();
+      return;
+    }
     let previousItemBounds: ReturnType<typeof determineItemBounds> | undefined;
 
     try {
@@ -69,7 +77,15 @@ export async function moveItemDown() {
   const text = await editor.getText();
 
   try {
-    const currentItemBounds = determineItemBounds(text, cursorPos);
+    let currentItemBounds: ReturnType<typeof determineItemBounds> | undefined;
+    try {
+      currentItemBounds = determineItemBounds(text, cursorPos);
+    } catch {
+      // If `determineItemBounds()` throws, that likely means the cursor is NOT in a bullet list,
+      // so we fall back to `moveLineDown()`
+      editor.moveLineDown();
+      return;
+    }
     let nextItemBounds: ReturnType<typeof determineItemBounds> | undefined;
     try {
       nextItemBounds = determineItemBounds(

web/syscalls/editor.ts

@@ -6,7 +6,14 @@ import {
   unfoldAll,
   unfoldCode,
 } from "@codemirror/language";
-import { deleteLine, isolateHistory, redo, undo } from "@codemirror/commands";
+import {
+  deleteLine,
+  isolateHistory,
+  moveLineDown,
+  moveLineUp,
+  redo,
+  undo,
+} from "@codemirror/commands";
 import type { Transaction } from "@codemirror/state";
 import { EditorView } from "@codemirror/view";
 import { getCM as vimGetCm, Vim } from "@replit/codemirror-vim";
@@ -309,6 +316,18 @@ export function editorSyscalls(client: Client): SysCallMapping {
     "editor.deleteLine": () => {
       deleteLine(client.editorView);
     },
+    "editor.moveLineUp": () => {
+      return moveLineUp({
+        state: client.editorView.state,
+        dispatch: client.editorView.dispatch,
+      });
+    },
+    "editor.moveLineDown": () => {
+      return moveLineDown({
+        state: client.editorView.state,
+        dispatch: client.editorView.dispatch,
+      });
+    },
     // Folding
     "editor.fold": () => {
       foldCode(client.editorView);