Add keyboard shortcuts to toggle between list and task list formats

README.md

@@ -190,6 +190,7 @@ Tip: also support the option `completion.root`
 | <kbd>Ctrl</kbd> + <kbd>Shift</kbd> + <kbd>]</kbd>                | Toggle heading (uplevel)         |
 | <kbd>Ctrl</kbd> + <kbd>Shift</kbd> + <kbd>[</kbd>                | Toggle heading (downlevel)       |
 | <kbd>Ctrl</kbd>/<kbd>Cmd</kbd> + <kbd>M</kbd>                    | Toggle math environment          |
+| <kbd>Shift</kbd> + <kbd>Alt</kbd> + <kbd>C</kbd>                 | Toggle list <--> task list       |
 | <kbd>Alt</kbd> + <kbd>C</kbd>                                    | Check/Uncheck task list item     |
 | <kbd>Ctrl</kbd>/<kbd>Cmd</kbd> + <kbd>Shift</kbd> + <kbd>V</kbd> | Toggle preview                   |
 | <kbd>Ctrl</kbd>/<kbd>Cmd</kbd> + <kbd>K</kbd> <kbd>V</kbd>       | Toggle preview to side           |

package.json

@@ -242,6 +242,11 @@
                 "mac": "cmd+[",
                 "when": "editorTextFocus && editorLangId =~ /^markdown$|^rmd$|^quarto$/ && !suggestWidgetVisible"
             },
+            {
+                "command": "markdown.extension.toggleTaskList",
+                "key": "shift+alt+c",
+                "when": "editorTextFocus && editorLangId =~ /^markdown$|^rmd$|^quarto$/"
+            },
             {
                 "command": "markdown.extension.checkTaskList",
                 "key": "alt+c",

src/listEditing.ts

@@ -11,6 +11,7 @@ export function activate(context: ExtensionContext) {
         commands.registerCommand('markdown.extension.onTabKey', onTabKey),
         commands.registerCommand('markdown.extension.onShiftTabKey', () => { return onTabKey('shift'); }),
         commands.registerCommand('markdown.extension.onBackspaceKey', onBackspaceKey),
+        commands.registerCommand('markdown.extension.toggleTaskList', toggleTaskList),
         commands.registerCommand('markdown.extension.checkTaskList', checkTaskList),
         commands.registerCommand('markdown.extension.onMoveLineDown', onMoveLineDown),
         commands.registerCommand('markdown.extension.onMoveLineUp', onMoveLineUp),
@@ -446,6 +447,57 @@ function deleteRange(editor: TextEditor, range: Range): Thenable<boolean> {
     );
 }
 
+function toggleTaskList(): Thenable<unknown> | void {
+    // - Look into lines that be lists/task-lists.
+    // - The first matching line dictates the new state for all further lines.
+    //   - I.e. if the first line is task-lists, only other task-lists lines will
+    //     be considered, and vice versa.
+    const editor = window.activeTextEditor!;
+    const listRegex = /^(\s*)([-+*]|[0-9]+[.)])(?! +\[[x ]\]) +/
+    const tasklistRegex = /^(\s*)([-+*]|[0-9]+[.)]) +\[[x ]\] */
+    let replaceRanges: Range[] = []
+    let newState: boolean | undefined = undefined // true = "- [ ]", false = "- ", undefined = no matching lines
+
+    // go through all touched lines of all selections.
+    for (const selection of editor.selections) {
+        for (let i = selection.start.line; i <= selection.end.line; i++) {
+            const line = editor.document.lineAt(i);
+            const lineStart = line.range.start;
+
+            if (!selection.isSingleLine && (selection.start.isEqual(line.range.end) || selection.end.isEqual(line.range.start))) {
+                continue;
+            }
+
+            let matches: RegExpExecArray | null;
+            if (
+                (matches = listRegex.exec(line.text))
+            ) {
+                if(newState === undefined)newState = true;
+            } else if (
+                (matches = tasklistRegex.exec(line.text))
+            ) {
+                if(newState === undefined)newState = false;
+            }
+
+            if(matches){
+                replaceRanges.push(new Range(
+                    lineStart.with({ character: matches[1].length }),
+                    lineStart.with({ character: matches[0].length}),
+                ));
+            }
+        }
+    }
+
+    if (newState !== undefined) {
+        const newChar = newState ? '- [ ] ' : '- ';
+        return editor.edit(editBuilder => {
+            for (const range of replaceRanges) {
+                editBuilder.replace(range, newChar);
+            }
+        });
+    }
+}
+
 function checkTaskList(): Thenable<unknown> | void {
     // - Look into selections for lines that could be checked/unchecked.
     // - The first matching line dictates the new state for all further lines.

src/test/suite/integration/listEditing.test.ts

@@ -227,6 +227,66 @@ suite("List editing.", () => {
             new Selection(0, 10, 0, 10));
     });
 
+    test("List/TaskList toggle. 1: Check single line,list to task list", () => {
+        return testCommand('markdown.extension.toggleTaskList',
+            [
+                '- test'
+            ],
+            new Selection(0, 0, 0, 0),
+            [
+                '- [ ] test'
+            ],
+            new Selection(0, 0, 0, 0),
+        );
+    });
+
+    test("List/TaskList toggle. 2: Check single line,task list to list", () => {
+        return testCommand('markdown.extension.toggleTaskList',
+            [
+                '-   [ ]   test'
+            ],
+            new Selection(0, 0, 0, 0),
+            [
+                '- test'
+            ],
+            new Selection(0, 0, 0, 0),
+        );
+    });
+
+    test("List/TaskList toggle. 3: Check multiple lines,list to task list", () => {
+        return testCommand('markdown.extension.toggleTaskList',
+            [
+                '- test',
+                '  -   test',
+                '- test',
+            ],
+            new Selection(1, 0, 2, 1),
+            [
+                '- test',
+                '  - [ ] test',
+                '- [ ] test',
+            ],
+            new Selection(1, 0, 2, 1),
+        );
+    });
+
+    test("List/TaskList toggle. 4: Check multiple lines,task list to list", () => {
+        return testCommand('markdown.extension.toggleTaskList',
+            [
+                '    -   [x] test',
+                '  - test',
+                '- [ ]  test',
+            ],
+            new Selection(0, 0, 2, 1),
+            [
+                '    - test',
+                '  - test',
+                '- test',
+            ],
+            new Selection(0, 0, 2, 1),
+        );
+    });
+
     test("List toggle. 1: Check single line", () => {
         return testCommand('markdown.extension.checkTaskList',
             [