Merge pull request #3082 from jramosg/issue-3078-toggle-comemnts-off-indent-glitch

Issue 3078 toggle comemnts off indent glitch
Fixes #3078

Author: jramosg

CHANGELOG.md

@@ -4,6 +4,7 @@ Changes to Calva.
 
 ## [Unreleased]
 
+- Fix: [Toggle comments off, indent glitch](https://github.com/BetterThanTomorrow/calva/issues/3078)
 - Fix: [Clojure-lsp not starting when offline](https://github.com/BetterThanTomorrow/calva/issues/1299)
 
 ## [2.0.555] - 2026-02-19

src/comment-prefix.ts

@@ -1,6 +1,16 @@
 /** Matches one or more leading semicolons (`;`, `;;`, `;;;`, etc.) */
 export const commentPrefixPattern = /^;+/;
 
+/**
+ * Calculates the end index for removing a comment prefix (semicolons + trailing space)
+ * from a line of text. Returns the index up to which characters should be removed,
+ * accounting for the semicolon(s) and a single trailing space (or all trailing spaces
+ * if the line is otherwise empty after the prefix).
+ *
+ * @param lineText - The full text of the line
+ * @param firstNonWhitespace - The index of the first non-whitespace character in the line
+ * @returns The end index for removal, or `undefined` if no comment prefix is found
+ */
 export function calculateCommentPrefixRemovalEnd(
   lineText: string,
   firstNonWhitespace: number
@@ -12,8 +22,20 @@ export function calculateCommentPrefixRemovalEnd(
   }
 
   let removalEnd = firstNonWhitespace + match[0].length;
-  while (removalEnd < lineText.length && lineText[removalEnd] === ' ') {
-    removalEnd++;
+  if (removalEnd < lineText.length && lineText[removalEnd] === ' ') {
+    let spaceRunEnd = removalEnd;
+    // If the line is otherwise empty after the comment prefix, remove all trailing spaces as well
+    while (spaceRunEnd < lineText.length && lineText[spaceRunEnd] === ' ') {
+      spaceRunEnd++;
+    }
+
+    // If we reached the end of the line, remove all spaces.
+    //  Otherwise, just remove one space after the comment prefix.
+    if (spaceRunEnd === lineText.length) {
+      removalEnd = spaceRunEnd;
+    } else {
+      removalEnd++;
+    }
   }
 
   return removalEnd;

src/edit.ts

@@ -395,7 +395,7 @@ async function updateLineComments(
   affectedLineNumbers: number[],
   shouldUncomment: boolean
 ) {
-  const descendingLineNumbers = [...new Set(affectedLineNumbers)].sort((a, b) => b - a);
+  const descendingLineNumbers = affectedLineNumbers.sort((a, b) => b - a);
 
   await editor.edit(
     (editBuilder) => {

src/extension-test/integration/suite/toggle-comment-test.ts

@@ -157,6 +157,24 @@ suite(suiteName, () => {
     );
   });
 
+  it('should preserve nested indentation when uncommenting selected multiline block (issue #3078)', async () => {
+    assert.equal(
+      await toggleCommentUsingActiveEditor(
+        '|;; (a (b c•;;       (d e•;;          f)•;;       g•;;       h)•;;    i•;;    j)|'
+      ),
+      '|(a (b c•      (d e•         f)•      g•      h)•   i•   j)|'
+    );
+  });
+
+  it('should preserve nested indentation when uncommenting selected multiline block inside defn (issue #3078)', async () => {
+    assert.equal(
+      await toggleCommentUsingActiveEditor(
+        '(defn foo []•  |;; (a (b c•  ;;       (d e•  ;;          f)•  ;;       g•  ;;       h)•  ;;    i•  ;;    j)|•     )'
+      ),
+      '(defn foo []•  |(a (b c•        (d e•           f)•        g•        h)•     i•     j)|)'
+    );
+  });
+
   it('should comment an empty line inside assoc with alignment indent (issue #2872)', async () => {
     assert.equal(
       await toggleCommentUsingActiveEditor('(assoc m•       :key :val•|)'),

src/extension-test/unit/edit/comment-prefix-test.ts

@@ -23,8 +23,16 @@ describe('prefix removal', () => {
     expect(stripLeadingCommentPrefix('  ;;; header')).toBe('  header');
   });
 
-  it('strips semicolon prefix and all immediate following spaces', () => {
-    expect(stripLeadingCommentPrefix(';;;   header')).toBe('header');
+  it('strips semicolon prefix and one separating space before content', () => {
+    expect(stripLeadingCommentPrefix(';;;   header')).toBe('  header');
+  });
+
+  it('preserves indentation spaces after comment prefix', () => {
+    expect(stripLeadingCommentPrefix(';;       h)')).toBe('      h)');
+  });
+
+  it('strips fully blank commented line to empty', () => {
+    expect(stripLeadingCommentPrefix(';;      ')).toBe('');
   });
 
   it('keeps non-comment lines unchanged', () => {