diff mercurial/debugcommands.py @ 47815:b30a53ffbf9b stable

debugcommands: introduce a debug command to repair repos affected by issue6528

This command is quite basic and slow, it will loop over the entirety of the
filelogs in the repository and check each revision for corruption, then fixes
the affected filelogs. It takes under 25 minutes for Mozilla-Central on my
not-top-of-the-line laptop, using the `--to-report` and `--from-report` options
will make this pretty tolerable to use, I think.

This change also introduces a test for the fix.

Differential Revision: https://phab.mercurial-scm.org/D11239

--- a/mercurial/debugcommands.py	Mon Aug 09 19:49:57 2021 -0400
+++ b/mercurial/debugcommands.py	Tue Jul 27 21:45:27 2021 +0200
@@ -71,6 +71,7 @@
     registrar,
     repair,
     repoview,
+    requirements,
     revlog,
     revset,
     revsetlang,
@@ -105,6 +106,7 @@
 from .revlogutils import (
     deltas as deltautil,
     nodemap,
+    rewrite,
     sidedata,
 )
 
@@ -1451,6 +1453,63 @@
         ui.write(b"%s\n" % f)
 
 
+@command(
+    b"debug-repair-issue6528",
+    [
+        (
+            b'',
+            b'to-report',
+            b'',
+            _(b'build a report of affected revisions to this file'),
+            _(b'FILE'),
+        ),
+        (
+            b'',
+            b'from-report',
+            b'',
+            _(b'repair revisions listed in this report file'),
+            _(b'FILE'),
+        ),
+    ]
+    + cmdutil.dryrunopts,
+)
+def debug_repair_issue6528(ui, repo, **opts):
+    """find affected revisions and repair them. See issue6528 for more details.
+
+    The `--to-report` and `--from-report` flags allow you to cache and reuse the
+    computation of affected revisions for a given repository across clones.
+    The report format is line-based (with empty lines ignored):
+
+    ```
+    <ascii-hex of the affected revision>,... <unencoded filelog index filename>
+    ```
+
+    There can be multiple broken revisions per filelog, they are separated by
+    a comma with no spaces. The only space is between the revision(s) and the
+    filename.
+
+    Note that this does *not* mean that this repairs future affected revisions,
+    that needs a separate fix at the exchange level that hasn't been written yet
+    (as of 5.9rc0).
+    """
+    cmdutil.check_incompatible_arguments(
+        opts, 'to_report', ['from_report', 'dry_run']
+    )
+    dry_run = opts.get('dry_run')
+    to_report = opts.get('to_report')
+    from_report = opts.get('from_report')
+    # TODO maybe add filelog pattern and revision pattern parameters to help
+    # narrow down the search for users that know what they're looking for?
+
+    if requirements.REVLOGV1_REQUIREMENT not in repo.requirements:
+        msg = b"can only repair revlogv1 repositories, v2 is not affected"
+        raise error.Abort(_(msg))
+
+    rewrite.repair_issue6528(
+        ui, repo, dry_run=dry_run, to_report=to_report, from_report=from_report
+    )
+
+
 @command(b'debugformat', [] + cmdutil.formatteropts)
 def debugformat(ui, repo, **opts):
     """display format information about the current repository