refactor: Remove regexes from Commands files to Task where they can be tested (#1006)

* refactor,fix: Move regexes out of untested Commands files

* removing something that should be a separate PR

* fix: update comments to remove reference to filename where used

* revert: no behavior change in refactor.
Leave regex test for cursor reset to be removed in later PR

* fix: mark checkbox regex as unicode so character escapes work correctly

Author: AnnaKornfeldSimpson

src/Commands/CreateOrEdit.ts

@@ -58,8 +58,7 @@ const taskFromLine = ({ line, path }: { line: string; path: string }): Task => {
 
     // If we are not on a line of a task, we take what we have.
     // The non-task line can still be a checklist, for example if it is lacking the global filter.
-    const nonTaskRegex: RegExp = /^([\s\t>]*)[-*]? *(\[(.)\])? *(.*)/u;
-    const nonTaskMatch = line.match(nonTaskRegex);
+    const nonTaskMatch = line.match(Task.nonTaskRegex);
     if (nonTaskMatch === null) {
         // Should never happen; everything in the regex is optional.
         console.error('Tasks: Cannot create task on line:', line);

src/Commands/ToggleDone.ts

@@ -34,8 +34,8 @@ export const toggleDone = (checking: boolean, editor: Editor, view: View) => {
     const toggledLine = toggleLine({ line, path });
     editor.setLine(lineNumber, toggledLine);
 
-    // The cursor is moved to the end of the line by default.
-    // If there is text on the line, put the cursor back where it was on the line.
+    // The cursor is moved to either the beginning of the line (usually) or the end of the line (if it was already at the end) by default.
+    // Put the cursor back where it was on the line (if there is "text" on the line -- preserves behavior but buggy, will fix in future PR).
     if (/[^ [\]*-]/.test(toggledLine)) {
         editor.setCursor({
             line: cursorPosition.line,
@@ -72,13 +72,12 @@ const toggleLine = ({ line, path }: { line: string; path: string }): string => {
             // 1. a list item
             // 2. a simple text line
 
-            const listItemRegex = /^([\s\t>]*)([-*])/;
-            if (listItemRegex.test(line)) {
+            if (Task.listItemRegex.test(line)) {
                 // Let's convert the list item to a checklist item.
-                toggledLine = line.replace(listItemRegex, '$1$2 [ ]');
+                toggledLine = line.replace(Task.listItemRegex, '$1$2 [ ]');
             } else {
                 // Let's convert the line to a list item.
-                toggledLine = line.replace(/^([\s\t>]*)/, '$1- ');
+                toggledLine = line.replace(Task.indentationRegex, '$1- ');
             }
         }
     }

src/Task.ts

@@ -84,11 +84,46 @@ export class Task {
 
     public static readonly dateFormat = 'YYYY-MM-DD';
 
+    // Matches indentation before a list marker (including > for potentially nested blockquotes or Obsidian callouts)
+    public static readonly indentationRegex = /^([\s\t>]*)/;
+
+    // Matches (but does not save) - or * list markers.
+    public static readonly listMarkerRegex = /[-*]/;
+
+    // Matches a checkbox and saves the status character inside
+    public static readonly checkboxRegex = /\[(.)\]/u;
+
+    // Matches the rest of the task after the checkbox.
+    public static readonly afterCheckboxRegex = / *(.*)/u;
+
     // Main regex for parsing a line. It matches the following:
-    // - Indentation (including > for potentially nested blockquotes or Obsidian callouts)
+    // - Indentation
     // - Status character
     // - Rest of task after checkbox markdown
-    public static readonly taskRegex = /^([\s\t>]*)[-*] +\[(.)\] *(.*)/u;
+    public static readonly taskRegex = new RegExp(
+        this.indentationRegex.source +
+            this.listMarkerRegex.source +
+            ' +' +
+            this.checkboxRegex.source +
+            this.afterCheckboxRegex.source,
+        'u',
+    );
+
+    // Used with the "Create or Edit Task" command to parse indentation and status if present
+    public static readonly nonTaskRegex = new RegExp(
+        this.indentationRegex.source +
+            this.listMarkerRegex.source +
+            '? *(' +
+            this.checkboxRegex.source +
+            ')?' +
+            this.afterCheckboxRegex.source,
+        'u',
+    );
+
+    // Used with "Toggle Done" command to detect a list item that can get a checkbox added to it.
+    public static readonly listItemRegex = new RegExp(
+        this.indentationRegex.source + '(' + this.listMarkerRegex.source + ')',
+    );
 
     // Match on block link at end.
     public static readonly blockLinkRegex = / \^[a-zA-Z0-9-]+$/u;