From de91c6429bc0358b69832db2e1fb9264a6b82a5f Mon Sep 17 00:00:00 2001
From: log0u7 <70974447+log0u7@users.noreply.github.com>
Date: Sun, 20 Sep 2026 01:26:20 +0200
Subject: [PATCH 1/2] fix(core): eliminate silent failures, WARN on every
 degraded outcome

Every swallowed failure now leaves a WARN trace (debug_mode-independent,
issue #5 contract) and the sidebar reports the truth:

- git#add_submodule: check the pointer commit, fail the add on error
- remove: check deinit + commit_removal; op label reflects commit failure;
  fix double vim_dir prefix on absolute module paths
- update: warn on unreachable pin target; stash push failure no longer
  pretends a stash exists (phantom pop); auto-commit failure downgrades
  the op and footer
- vimrc/helptags/check/async/add/declare/backup/util: warn on the
  previously invisible failure branches

tests/log_warnings.vader: 15 WARN regression tests with debug_mode unset.
Closes #7
---
 CHANGELOG.md                             |  33 +++
 autoload/plugin_manager/async.vim        |   5 +-
 autoload/plugin_manager/cmd/add.vim      |   3 +
 autoload/plugin_manager/cmd/backup.vim   |  13 +-
 autoload/plugin_manager/cmd/check.vim    |   5 +-
 autoload/plugin_manager/cmd/declare.vim  |   4 +
 autoload/plugin_manager/cmd/helptags.vim |  10 +
 autoload/plugin_manager/cmd/remove.vim   |  54 +++-
 autoload/plugin_manager/cmd/update.vim   |  61 ++++-
 autoload/plugin_manager/core/util.vim    |   4 +
 autoload/plugin_manager/git.vim          |  16 +-
 autoload/plugin_manager/vimrc.vim        |   4 +-
 tests/log_warnings.vader                 | 321 +++++++++++++++++++++++
 13 files changed, 502 insertions(+), 31 deletions(-)
 create mode 100644 tests/log_warnings.vader

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8ef357c..c42dbfe 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,39 @@
 
 All notable changes to the Vim Plugin Manager will be documented in this file.
 
+## [Unreleased]
+
+### Fixed
+- **No silent failures left** (#7): every degraded outcome writes a WARN
+  line (always logged, `debug_mode`-independent) and sidebar labels tell
+  the truth:
+  - `git#add_submodule`: the pointer commit result is checked; a failure
+    warns and fails the add instead of returning success.
+  - `remove`: `git submodule deinit` and `commit_removal` results are
+    checked; a failed pointer commit downgrades the op to
+    "Removed (pointer commit failed)" instead of a plain "Removed".
+  - `remove`: a module path that is already absolute is no longer
+    prefixed with `vim_dir` twice (filesystem-search removals).
+  - `update`: unreachable pin target warns, not sidebar-only.
+  - `update`: `stash_if_needed` returns 0 when `git stash push` fails
+    (previously returned 1, causing a phantom `stash pop`).
+  - `update`: auto-commit failures downgrade the op to
+    "Updated (auto-commit failed)" and add a truthful footer line.
+  - `vimrc`: unparsable declarations log at WARN instead of the
+    debug-gated level.
+  - `helptags`: a real `:helptags` failure is reported as
+    "Helptags failed" + WARN, no longer as the "skip / No doc directory".
+  - `check`: empty catch around `on_done` now warns.
+  - `async`: callback errors write a WARN in addition to `:messages`.
+  - `add` (local): post-install exec failure warns.
+  - `declare`: invalid URL format warns (both sync and async batch paths).
+  - `backup`: `cp` and `git add` results are checked and warn.
+  - `util#ensure_directory`: mkdir failures warn.
+
+### Added
+- `tests/log_warnings.vader`: 15 regression tests asserting the WARN line
+  exists with `debug_mode` unset (contract from issue #5).
+
 ## [2.2.7] - 2026-09-19
 
 ### Fixed
diff --git a/autoload/plugin_manager/async.vim b/autoload/plugin_manager/async.vim
index 7672ce7..016ef67 100644
--- a/autoload/plugin_manager/async.vim
+++ b/autoload/plugin_manager/async.vim
@@ -350,7 +350,10 @@ function! s:process_job_completion(job_id) abort
         \ 'cmd': l:job.cmd
         \ })
     catch
-      " Handle callback errors
+      " Handle callback errors: surface on :messages and in the log (a
+      " swallowed callback error must never be invisible).
+      call plugin_manager#core#log#warn('async',
+            \ 'async callback error: ' . v:exception)
       echohl ErrorMsg
       echomsg "Error in async callback: " . v:exception
       echohl None
diff --git a/autoload/plugin_manager/cmd/add.vim b/autoload/plugin_manager/cmd/add.vim
index 6c7fdc3..7fa7e8e 100644
--- a/autoload/plugin_manager/cmd/add.vim
+++ b/autoload/plugin_manager/cmd/add.vim
@@ -131,6 +131,9 @@ function! s:install_local_plugin(path, options) abort
     if !empty(get(a:options, 'exec', ''))
       let l:result = plugin_manager#core#util#run_in_dir(a:options.exec, l:plugin_dir)
       if !l:result.success
+        call plugin_manager#ui#log_detail('add',
+              \ 'post-install exec failed: ' . a:options.exec . ' - '
+              \ . l:result.output, 'warn')
         call plugin_manager#ui#complete_operation(l:op_id, 'fail', 'Exec failed')
         return 0
       endif
diff --git a/autoload/plugin_manager/cmd/backup.vim b/autoload/plugin_manager/cmd/backup.vim
index 2327e13..e5683aa 100644
--- a/autoload/plugin_manager/cmd/backup.vim
+++ b/autoload/plugin_manager/cmd/backup.vim
@@ -48,8 +48,17 @@ function! s:backup_vimrc_file() abort
   if plugin_manager#core#util#file_exists(l:vimrc_path)
     let l:copy_cmd = 'cp ' . shellescape(l:vimrc_path) . ' ' . shellescape(l:local_vimrc)
     let l:vim_dir = plugin_manager#core#util#get_config('vim_dir', '')
-    call plugin_manager#core#util#run_in_dir(l:copy_cmd, '')
-    call plugin_manager#git#execute('git add ' . shellescape(l:local_vimrc), l:vim_dir, 0, 0)
+    let l:copy_result = plugin_manager#core#util#run_in_dir(l:copy_cmd, '')
+    if !l:copy_result.success
+      call plugin_manager#ui#log_detail('backup',
+            \ 'backup cp failed: ' . l:copy_result.output, 'warn')
+    endif
+    let l:add_result = plugin_manager#git#execute(
+          \ 'git add ' . shellescape(l:local_vimrc), l:vim_dir, 0, 0)
+    if !l:add_result.success
+      call plugin_manager#ui#log_detail('backup',
+            \ 'backup git add failed: ' . l:add_result.output, 'warn')
+    endif
   endif
 endfunction
 
diff --git a/autoload/plugin_manager/cmd/check.vim b/autoload/plugin_manager/cmd/check.vim
index fdfbe24..3dbf76c 100644
--- a/autoload/plugin_manager/cmd/check.vim
+++ b/autoload/plugin_manager/cmd/check.vim
@@ -220,7 +220,10 @@ function! s:finish(plugins, opts) abort
     try
       call a:opts.on_done(a:plugins)
     catch
-      " Do not let callback failures bubble up
+      " Do not let callback failures bubble up, but leave a trace: a
+      " swallowed callback error must never be invisible.
+      call plugin_manager#core#log#warn('check',
+            \ 'on_done callback failed: ' . v:exception)
     endtry
   endif
 endfunction
diff --git a/autoload/plugin_manager/cmd/declare.vim b/autoload/plugin_manager/cmd/declare.vim
index 2e37759..3e3860a 100644
--- a/autoload/plugin_manager/cmd/declare.vim
+++ b/autoload/plugin_manager/cmd/declare.vim
@@ -140,6 +140,8 @@ function! s:process_declarations_async() abort
     if empty(l:full_url) || empty(l:name)
       let l:op_id = plugin_manager#ui#start_operation(
             \ empty(l:name) ? fnamemodify(l:plugin.url, ':t') : l:name, 'Processing')
+      call plugin_manager#ui#log_detail('declare',
+            \ 'invalid URL format: ' . l:plugin.url, 'warn')
       call plugin_manager#ui#complete_operation(l:op_id, 'fail', 'Invalid URL format')
       let l:ctx.errors += 1
       continue
@@ -266,6 +268,8 @@ function! s:process_plugin(url, options) abort
   let l:full_url = plugin_manager#core#util#convert_to_full_url(a:url)
   if empty(l:full_url)
     let l:plugin_name = fnamemodify(a:url, ':t')
+    call plugin_manager#ui#log_detail('declare',
+          \ 'invalid URL format: ' . a:url, 'warn')
     let l:op_id = plugin_manager#ui#start_operation(l:plugin_name, 'Processing')
     call plugin_manager#ui#complete_operation(l:op_id, 'fail', 'Invalid URL format')
     return 'error'
diff --git a/autoload/plugin_manager/cmd/helptags.vim b/autoload/plugin_manager/cmd/helptags.vim
index 4f7de8e..89f56b5 100644
--- a/autoload/plugin_manager/cmd/helptags.vim
+++ b/autoload/plugin_manager/cmd/helptags.vim
@@ -123,6 +123,12 @@ function! s:generate_for_plugin(plugin_name, plugin_path, ...) abort
   if s:generate_helptag(a:plugin_path)
     call plugin_manager#ui#complete_operation(l:op_id, 'ok', 'Helptags generated')
     return 1
+  elseif isdirectory(a:plugin_path . '/doc')
+    " The doc directory exists but :helptags failed: that is a failure,
+    " not a skip - label it truthfully (details in the log).
+    call plugin_manager#ui#complete_operation(l:op_id, 'fail',
+          \ 'Helptags failed (see log)')
+    return 0
   else
     call plugin_manager#ui#complete_operation(l:op_id, 'skip', 'No doc directory')
     return 0
@@ -140,6 +146,10 @@ function! s:generate_helptag(plugin_path) abort
       execute 'helptags ' . fnameescape(l:doc_path)
       return 1
     catch
+      " A failed :helptags used to be indistinguishable from a missing doc
+      " directory: warn so the real error is visible in a default setup.
+      call plugin_manager#core#log#warn('helptags',
+            \ 'helptags failed in ' . a:plugin_path . ': ' . v:exception)
       return 0
     endtry
   endif
diff --git a/autoload/plugin_manager/cmd/remove.vim b/autoload/plugin_manager/cmd/remove.vim
index 3e74fa6..a260089 100644
--- a/autoload/plugin_manager/cmd/remove.vim
+++ b/autoload/plugin_manager/cmd/remove.vim
@@ -163,34 +163,49 @@ function! s:remove_module(module_name, module_path) abort
   let l:module_info = s:get_module_metadata(a:module_path)
 
   " git submodule deinit and git rm take the repo-relative path as argument
-  " but must run inside the repo root (vim_dir).
-  call plugin_manager#git#execute(
-        \ 'git submodule deinit -f ' . shellescape(a:module_path), l:vim_dir, 0, 0)
+  " but must run inside the repo root (vim_dir).  Discovery may hand us an
+  " absolute path (filesystem search): normalize so the vim_dir prefix is
+  " never applied twice.
+  let l:rel_path = plugin_manager#core#util#make_relative_path(a:module_path)
+
+  let l:deinit_result = plugin_manager#git#execute(
+        \ 'git submodule deinit -f ' . shellescape(l:rel_path), l:vim_dir, 0, 0)
+  if !l:deinit_result.success
+    call plugin_manager#ui#log_detail('remove',
+          \ 'submodule deinit failed for ' . l:rel_path . ': '
+          \ . l:deinit_result.output, 'warn')
+  endif
   let l:result = plugin_manager#git#execute(
-        \ 'git rm -f ' . shellescape(a:module_path), l:vim_dir, 0, 0)
+        \ 'git rm -f ' . shellescape(l:rel_path), l:vim_dir, 0, 0)
 
   if !l:result.success
     " Fallback: delete the working tree directory directly using absolute path
-    let l:abs_path = empty(l:vim_dir) ? a:module_path : (l:vim_dir . '/' . a:module_path)
+    let l:abs_path = empty(l:vim_dir) ? l:rel_path : (l:vim_dir . '/' . l:rel_path)
     call plugin_manager#ui#log_detail('remove', 'git rm failed, removing path manually: ' . l:abs_path, 'warn')
     call plugin_manager#core#util#remove_path(l:abs_path)
   endif
 
   " Remove the cached git metadata for this submodule (absolute path)
-  let l:git_modules_path = l:vim_dir . '/.git/modules/' . a:module_path
+  let l:git_modules_path = l:vim_dir . '/.git/modules/' . l:rel_path
   if plugin_manager#core#util#dir_exists(l:git_modules_path)
     call plugin_manager#core#util#remove_path(l:git_modules_path)
   endif
 
   " Removal outcome: the working tree directory must be gone. Report the
   " truth instead of an unconditional 'ok'.
-  let l:abs_module = empty(l:vim_dir) ? a:module_path : (l:vim_dir . '/' . a:module_path)
+  let l:abs_module = empty(l:vim_dir) ? l:rel_path : (l:vim_dir . '/' . l:rel_path)
   let l:success = !plugin_manager#core#util#dir_exists(l:abs_module)
 
   if l:success
-    call s:commit_removal(a:module_name, l:module_info)
-    call plugin_manager#ui#complete_operation(l:op_id, 'ok', 'Removed')
-    call plugin_manager#ui#footer([plugin_manager#ui#success('Plugin removed')])
+    if s:commit_removal(a:module_name, l:module_info)
+      call plugin_manager#ui#complete_operation(l:op_id, 'ok', 'Removed')
+      call plugin_manager#ui#footer([plugin_manager#ui#success('Plugin removed')])
+    else
+      call plugin_manager#ui#complete_operation(l:op_id, 'warn',
+            \ 'Removed (pointer commit failed: see log)')
+      call plugin_manager#ui#footer([plugin_manager#ui#warning(
+            \ 'Plugin removed, but the pointer commit failed (see log)')])
+    endif
   else
     call plugin_manager#ui#complete_operation(l:op_id, 'fail',
           \ 'Removal incomplete: ' . l:abs_module . ' still exists (see log)')
@@ -216,6 +231,9 @@ function! s:get_module_metadata(module_path) abort
   return {}
 endfunction
 
+" Stage the .gitmodules update and record the removal as its own history
+" entry.  Returns 1 when a commit was created, 0 when every commit attempt
+" failed (the failure is logged: the pointer state is degraded).
 function! s:commit_removal(module_name, module_info) abort
   let l:commit_msg = "Remove " . a:module_name . " plugin"
   let l:vim_dir = plugin_manager#core#util#get_config('vim_dir', '')
@@ -225,13 +243,25 @@ function! s:commit_removal(module_name, module_info) abort
   endif
 
   " Stage .gitmodules (updated by git rm); run in vim_dir for repo-root scope.
-  call plugin_manager#git#execute('git add .gitmodules', l:vim_dir, 0, 0)
+  let l:add_result = plugin_manager#git#execute(
+        \ 'git add .gitmodules', l:vim_dir, 0, 0)
+  if !l:add_result.success
+    call plugin_manager#ui#log_detail('remove',
+          \ 'git add .gitmodules failed: ' . l:add_result.output, 'warn')
+  endif
   " Try to commit; if nothing to commit (already removed via rm), create an
   " empty commit so the removal is recorded as a separate history entry.
   let l:result = plugin_manager#git#execute(
         \ 'git commit -m ' . shellescape(l:commit_msg), l:vim_dir, 0, 0)
   if !l:result.success
-    call plugin_manager#git#execute(
+    let l:result = plugin_manager#git#execute(
           \ 'git commit --allow-empty -m ' . shellescape(l:commit_msg), l:vim_dir, 0, 0)
   endif
+  if !l:result.success
+    call plugin_manager#ui#log_detail('remove',
+          \ 'pointer commit failed for ' . a:module_name . ': '
+          \ . l:result.output, 'warn')
+    return 0
+  endif
+  return 1
 endfunction
\ No newline at end of file
diff --git a/autoload/plugin_manager/cmd/update.vim b/autoload/plugin_manager/cmd/update.vim
index 26aa17b..a604055 100644
--- a/autoload/plugin_manager/cmd/update.vim
+++ b/autoload/plugin_manager/cmd/update.vim
@@ -159,7 +159,10 @@ function! s:on_update_complete(ctx, result) abort
       call plugin_manager#ui#complete_operation(l:op_id, 'ok', 'Updated')
       call plugin_manager#cmd#helptags#execute(0, l:module_name, 1)
       let l:module_path = get(a:ctx.current_module, 'path', '')
-      call s:commit_update_async(l:module_name, l:module_path)
+      if s:commit_update_async(l:module_name, l:module_path)
+        call plugin_manager#ui#complete_operation(l:op_id, 'warn',
+              \ 'Updated (auto-commit failed: see log)')
+      endif
     else
       call plugin_manager#ui#complete_operation(l:op_id, 'info', 'Up-to-date')
     endif
@@ -239,6 +242,9 @@ function! s:sync_pinned(ctx, module, pin, current_commit, op_id) abort
   let l:res = plugin_manager#git#execute(
         \ 'git rev-parse ' . shellescape(l:ref . '^{commit}'), l:module_path, 0, 0)
   if !l:res.success
+    " The sidebar alone hides this from :PluginManagerViewLog: warn too.
+    call plugin_manager#core#log#warn('update',
+          \ 'Pin target not found: ' . l:ref . ' in ' . l:module_path)
     call plugin_manager#ui#complete_operation(a:op_id, 'fail',
           \ 'Pin target not found: ' . l:ref)
     call s:pin_done(a:ctx, a:module, 0)
@@ -299,7 +305,10 @@ function! s:pin_done(ctx, module, changed) abort
   elseif a:changed
     call plugin_manager#cmd#helptags#execute(0, a:module.short_name, 1)
     let l:module_path = get(get(a:ctx, 'current_module', {}), 'path', '')
-    call s:commit_update_async(a:module.short_name, l:module_path)
+    if s:commit_update_async(a:module.short_name, l:module_path)
+      call plugin_manager#ui#complete_operation(s:op_id_for(a:ctx, a:module),
+            \ 'warn', 'Updated (auto-commit failed: see log)')
+    endif
   endif
 endfunction
 
@@ -485,25 +494,37 @@ function! s:maybe_finalize(ctx) abort
 endfunction
 
 function! s:finalize_update_all(ctx) abort
+  let l:commit_failed = 0
   if !empty(a:ctx.updated_modules)
     if plugin_manager#core#util#should_auto_commit()
       let l:vd = plugin_manager#core#util#get_config('vim_dir', '')
-      call s:log_silent_failure('git add .gitmodules',
+      let l:commit_failed = s:log_silent_failure('git add .gitmodules',
             \ plugin_manager#git#execute('git add .gitmodules', l:vd, 0, 0))
       for l:module in a:ctx.updated_modules
-        call s:log_silent_failure('git add ' . l:module.path,
+        let l:commit_failed = s:log_silent_failure('git add ' . l:module.path,
               \ plugin_manager#git#execute(
               \   'git add ' . shellescape(l:module.path), l:vd, 0, 0))
+              \ || l:commit_failed
       endfor
-      call s:log_silent_failure('commit',
+      let l:commit_failed = s:log_silent_failure('commit',
             \ plugin_manager#git#execute(
             \   'git commit -m "Update Modules"', l:vd, 0, 0))
+            \ || l:commit_failed
     endif
     for l:module in a:ctx.updated_modules
       call plugin_manager#cmd#helptags#execute(0, l:module.short_name, 1)
     endfor
   endif
 
+  " Truthful completion: the plugins updated, but the pointer commit is the
+  " part that persists the update - a failure must not read as a clean win.
+  if l:commit_failed
+    for l:module in a:ctx.updated_modules
+      call plugin_manager#ui#complete_operation(a:ctx.ops[l:module.short_name],
+            \ 'warn', 'Updated (auto-commit failed: see log)')
+    endfor
+  endif
+
   let l:n = len(a:ctx.updated_modules)
   let l:total = len(a:ctx.valid_modules)
   let l:failed = len(get(a:ctx, 'fetch_failed', {}))
@@ -520,6 +541,10 @@ function! s:finalize_update_all(ctx) abort
     call add(l:footer, plugin_manager#ui#warning(
           \ l:failed . ' of ' . l:total . ' plugins failed to fetch'))
   endif
+  if l:commit_failed
+    call add(l:footer, plugin_manager#ui#warning(
+          \ 'auto-commit failed (see log): the update is not recorded in git'))
+  endif
   call plugin_manager#ui#footer(l:footer)
 endfunction
 
@@ -529,11 +554,14 @@ endfunction
 
 " Log silent git failures (git#execute with throw_on_error=0): a failed
 " pointer add/commit must leave a trace in the log, not vanish.
+" Returns 1 when the step failed, 0 otherwise.
 function! s:log_silent_failure(step, res) abort
   if !a:res.success
     call plugin_manager#ui#log_detail('update',
           \ 'auto-commit ' . a:step . ' failed: ' . a:res.output, 'warn')
+    return 1
   endif
+  return 0
 endfunction
 
 " Stash local changes if any exist. Returns 1 if a stash was created, 0 otherwise.
@@ -545,7 +573,14 @@ function! s:stash_if_needed(module_path) abort
   if !l:status.success || empty(trim(l:status.output))
     return 0
   endif
-  call plugin_manager#git#execute('git stash push -u -q', a:module_path, 0, 0)
+  let l:stash_result = plugin_manager#git#execute('git stash push -u -q', a:module_path, 0, 0)
+  if !l:stash_result.success
+    " Never claim a stash exists when the push failed: the caller would
+    " otherwise pop an unrelated stash after the pull.
+    call plugin_manager#ui#log_detail('update',
+          \ 'stash push failed in ' . a:module_path . ': ' . l:stash_result.output, 'warn')
+    return 0
+  endif
   return 1
 endfunction
 
@@ -562,21 +597,27 @@ function! s:stash_pop(module_path, op_id) abort
   endif
 endfunction
 
+" Auto-commit the pointer for a single updated module (mirror of
+" s:finalize_update_all).  Returns 1 when any step failed so the caller can
+" re-complete the operation with a truthful warn.
 function! s:commit_update_async(module_name, module_path) abort
   if !plugin_manager#core#util#should_auto_commit()
-    return
+    return 0
   endif
   let l:vim_dir = plugin_manager#core#util#get_config('vim_dir', '')
   " Three separate calls (mirrors s:finalize_update_all): a compound command
   " would only scope the first git -C, and the module name must stay escaped
   " so it can never break out of the commit message quoting.
-  call s:log_silent_failure('git add .gitmodules',
+  let l:failed = s:log_silent_failure('git add .gitmodules',
         \ plugin_manager#git#execute('git add .gitmodules', l:vim_dir, 0, 0))
-  call s:log_silent_failure('git add ' . a:module_path,
+  let l:failed = s:log_silent_failure('git add ' . a:module_path,
         \ plugin_manager#git#execute(
         \   'git add ' . shellescape(a:module_path), l:vim_dir, 0, 0))
-  call s:log_silent_failure('commit',
+        \ || l:failed
+  let l:failed = s:log_silent_failure('commit',
         \ plugin_manager#git#execute(
         \   'git commit -m ' . shellescape('Update Module: ' . a:module_name),
         \   l:vim_dir, 0, 0))
+        \ || l:failed
+  return l:failed
 endfunction
diff --git a/autoload/plugin_manager/core/util.vim b/autoload/plugin_manager/core/util.vim
index fcc16a3..cc0522e 100644
--- a/autoload/plugin_manager/core/util.vim
+++ b/autoload/plugin_manager/core/util.vim
@@ -90,6 +90,10 @@ function! plugin_manager#core#util#ensure_directory(dir) abort
       call mkdir(l:dir, 'p')
       return 1
     catch
+      " A silent mkdir failure cascades into confusing downstream errors:
+      " warn so the real cause is visible.
+      call plugin_manager#core#log#warn('util',
+            \ 'mkdir failed: ' . l:dir . ': ' . v:exception)
       return 0
     endtry
   endif
diff --git a/autoload/plugin_manager/git.vim b/autoload/plugin_manager/git.vim
index 1fbf3c2..a62ecd5 100644
--- a/autoload/plugin_manager/git.vim
+++ b/autoload/plugin_manager/git.vim
@@ -563,7 +563,9 @@ function! plugin_manager#git#add_submodule(url, install_dir, options) abort
     endif
   endif
 
-  " Commit changes (must run at repo root)
+  " Commit changes (must run at repo root).  A failed pointer commit
+  " leaves the submodule unrecorded: never swallow it - warn and fail the
+  " add so the caller reports the degraded outcome.
   let l:commit_msg = 'Add ' . a:url . ' plugin'
   if !empty(a:options.branch)
     let l:commit_msg .= ' (branch: ' . a:options.branch . ')'
@@ -571,9 +573,15 @@ function! plugin_manager#git#add_submodule(url, install_dir, options) abort
     let l:commit_msg .= ' (tag: ' . a:options.tag . ')'
   endif
 
-  call plugin_manager#git#execute('git commit -m ' . shellescape(l:commit_msg), l:vim_dir, 1, 0)
-  
-  return l:result.success
+  let l:commit_result = plugin_manager#git#execute(
+        \ 'git commit -m ' . shellescape(l:commit_msg), l:vim_dir, 1, 0)
+  if !l:commit_result.success
+    call plugin_manager#core#log#warn('git',
+          \ 'pointer commit failed for ' . l:relative_path . ': '
+          \ . l:commit_result.output)
+  endif
+
+  return l:result.success && l:commit_result.success
 endfunction
 
 
diff --git a/autoload/plugin_manager/vimrc.vim b/autoload/plugin_manager/vimrc.vim
index 0f62807..e54282e 100644
--- a/autoload/plugin_manager/vimrc.vim
+++ b/autoload/plugin_manager/vimrc.vim
@@ -51,7 +51,9 @@ function! s:eval_declaration(rest) abort
     endif
   endif
   if empty(l:args) || type(get(l:args, 0, '')) != v:t_string
-    call plugin_manager#core#log#debug('vimrc',
+    " Warn, not debug: a silently skipped declaration must be visible in a
+    " default setup (debug_mode off), same contract as issue #5.
+    call plugin_manager#core#log#warn('vimrc',
           \ 'skipping unparsable declaration: ' . a:rest)
     return {}
   endif
diff --git a/tests/log_warnings.vader b/tests/log_warnings.vader
new file mode 100644
index 0000000..dc1a805
--- /dev/null
+++ b/tests/log_warnings.vader
@@ -0,0 +1,321 @@
+" Regression tests: every degraded outcome must leave a WARN line in the log
+" with debug_mode NOT set (contract from issue #5 / log#warn).  Each Execute
+" block starts by deleting the log so assertions are case-local.
+" Fixture mirrors tests/update.vader (bare remote + vim repo + submodule).
+
+Before:
+  let g:_pm_lw_saved = {
+        \ 'vim_dir':     get(g:, 'plugin_manager_vim_dir', ''),
+        \ 'cwd':         getcwd(),
+        \ 'plugins_dir': get(g:, 'plugin_manager_plugins_dir', ''),
+        \ 'vimrc':       get(g:, 'plugin_manager_vimrc_path', ''),
+        \ 'logging':     get(g:, 'plugin_manager_enable_logging', 0),
+        \ 'auto_commit': get(g:, 'plugin_manager_auto_commit_on_update', 1),
+        \ }
+
+  let g:_pm_lw_root    = tempname()
+  let g:_pm_lw_bare    = g:_pm_lw_root . '/myplugin.git'
+  let g:_pm_lw_vim     = g:_pm_lw_root . '/vim'
+  let g:_pm_lw_plug    = g:_pm_lw_vim  . '/pack/plugins/start/myplugin'
+  let g:_pm_lw_src     = g:_pm_lw_root . '/src'
+  let g:_pm_lw_vimrc   = g:_pm_lw_root . '/ext-vimrc'
+  let g:_pm_lw_local   = g:_pm_lw_root . '/localsrc'
+  let g:_pm_lw_log     = g:_pm_lw_vim  . '/logs/plugin_manager.log'
+
+  call mkdir(g:_pm_lw_root, 'p')
+
+  " 1. Bare remote (named myplugin.git so extract_plugin_name matches)
+  call system('git init --bare ' . shellescape(g:_pm_lw_bare))
+  call system('git -C ' . shellescape(g:_pm_lw_bare) . ' symbolic-ref HEAD refs/heads/main')
+
+  " 2. Source working tree: initial commit pushed to the bare
+  call mkdir(g:_pm_lw_src, 'p')
+  call system('git init ' . shellescape(g:_pm_lw_src))
+  call system('git -C ' . shellescape(g:_pm_lw_src) . ' config user.email "test@test.com"')
+  call system('git -C ' . shellescape(g:_pm_lw_src) . ' config user.name "Test"')
+  call system('git -C ' . shellescape(g:_pm_lw_src)
+        \ . ' remote add origin ' . shellescape(g:_pm_lw_bare))
+  call writefile(['v1'], g:_pm_lw_src . '/file.txt')
+  call system('git -C ' . shellescape(g:_pm_lw_src) . ' add .')
+  call system('git -C ' . shellescape(g:_pm_lw_src) . ' commit -m "initial"')
+  call system('git -C ' . shellescape(g:_pm_lw_src) . ' push -q origin HEAD:main '
+        \ . '2>/dev/null || git -C ' . shellescape(g:_pm_lw_src)
+        \ . ' push -q --set-upstream origin HEAD:main')
+  call system('git -C ' . shellescape(g:_pm_lw_bare) . ' symbolic-ref HEAD refs/heads/main')
+
+  " 3. Vim config dir as a git repo
+  call mkdir(g:_pm_lw_vim, 'p')
+  call system('git init ' . shellescape(g:_pm_lw_vim))
+  call system('git -C ' . shellescape(g:_pm_lw_vim) . ' config user.email "test@test.com"')
+  call system('git -C ' . shellescape(g:_pm_lw_vim) . ' config user.name "Test"')
+
+  " 4. Submodule + local plugin source
+  call mkdir(g:_pm_lw_vim . '/pack/plugins/start', 'p')
+  call system('git -C ' . shellescape(g:_pm_lw_vim)
+        \ . ' -c protocol.file.allow=always submodule add '
+        \ . shellescape('file://' . g:_pm_lw_bare) . ' pack/plugins/start/myplugin')
+  call system('git -C ' . shellescape(g:_pm_lw_vim) . ' commit -m "add submodule"')
+  call mkdir(g:_pm_lw_local, 'p')
+  call writefile(['x'], g:_pm_lw_local . '/code.vim')
+
+  " 5. Point the manager at the fixture.  debug_mode is deliberately NOT
+  "    set: the WARN contract must hold in a default setup.
+  let g:plugin_manager_vim_dir        = g:_pm_lw_vim
+  let g:plugin_manager_plugins_dir    = g:_pm_lw_vim . '/pack/plugins'
+  let g:plugin_manager_vimrc_path     = g:_pm_lw_root . '/absent.vimrc'
+  let g:plugin_manager_enable_logging = 1
+  unlet! g:plugin_manager_debug_mode
+  " Self-healing: an earlier aborted test can leave an emptied git identity
+  " in the environment, which would break every fixture commit below.
+  unlet! $GIT_AUTHOR_NAME $GIT_AUTHOR_EMAIL
+  unlet! $GIT_COMMITTER_NAME $GIT_COMMITTER_EMAIL
+  let g:plugin_manager_test_force_sync = 1
+
+  execute 'cd ' . fnameescape(g:_pm_lw_vim)
+
+  let s:_pm_lw_buf = bufnr('PluginManager')
+  if s:_pm_lw_buf != -1
+    execute 'bwipeout! ' . s:_pm_lw_buf
+  endif
+
+  call plugin_manager#git#refresh_modules_cache()
+
+  " Read the whole log as one string (empty when the file does not exist).
+  function! g:_pm_lw_logtext() abort
+    if filereadable(g:_pm_lw_log)
+      return join(readfile(g:_pm_lw_log), "\n")
+    endif
+    return ''
+  endfunction
+
+After:
+  execute 'cd ' . fnameescape(g:_pm_lw_saved.cwd)
+  if isdirectory(g:_pm_lw_root)
+    call delete(g:_pm_lw_root, 'rf')
+  endif
+  unlet! $GIT_AUTHOR_NAME $GIT_AUTHOR_EMAIL
+  unlet! $GIT_COMMITTER_NAME $GIT_COMMITTER_EMAIL
+  let g:plugin_manager_vim_dir     = g:_pm_lw_saved.vim_dir
+  let g:plugin_manager_plugins_dir = g:_pm_lw_saved.plugins_dir
+  let g:plugin_manager_vimrc_path  = g:_pm_lw_saved.vimrc
+  let g:plugin_manager_enable_logging = g:_pm_lw_saved.logging
+  let g:plugin_manager_auto_commit_on_update = g:_pm_lw_saved.auto_commit
+  unlet! g:plugin_manager_test_force_sync
+  unlet g:_pm_lw_saved g:_pm_lw_root g:_pm_lw_bare g:_pm_lw_vim g:_pm_lw_plug
+  unlet g:_pm_lw_src g:_pm_lw_vimrc g:_pm_lw_local g:_pm_lw_log
+  let s:_pm_lw_buf2 = bufnr('PluginManager')
+  if s:_pm_lw_buf2 != -1
+    execute 'bwipeout! ' . s:_pm_lw_buf2
+  endif
+  call plugin_manager#git#refresh_modules_cache()
+
+Execute (ensure_directory logs a WARN when mkdir fails):
+  call delete(g:_pm_lw_log)
+  call writefile(['x'], g:_pm_lw_root . '/blocker')
+  call plugin_manager#core#util#ensure_directory(g:_pm_lw_root . '/blocker/child')
+  Assert g:_pm_lw_logtext() =~# 'mkdir failed',
+        \ 'mkdir failure must be logged, got: ' . g:_pm_lw_logtext()
+
+Execute (unparsable vimrc declaration logs a WARN, not a gated debug):
+  call delete(g:_pm_lw_log)
+  call writefile(["Plugin 'unclosed-string"], g:_pm_lw_vimrc)
+  let g:plugin_manager_vimrc_path = g:_pm_lw_vimrc
+  call plugin_manager#vimrc#parse_declarations()
+  let g:plugin_manager_vimrc_path = g:_pm_lw_root . '/absent.vimrc'
+  Assert g:_pm_lw_logtext() =~# 'skipping unparsable declaration',
+        \ 'unparsable declaration must warn, got: ' . g:_pm_lw_logtext()
+
+Execute (check on_done callback failure logs a WARN):
+  call delete(g:_pm_lw_log)
+  function! g:_pm_lw_boom(...) abort
+    throw 'on-done-boom'
+  endfunction
+  call plugin_manager#cmd#check#execute(
+        \ {'silent': 1, 'on_done': function('g:_pm_lw_boom')})
+  delfunction g:_pm_lw_boom
+  Assert g:_pm_lw_logtext() =~# 'on_done callback failed',
+        \ 'on_done failure must be logged, got: ' . g:_pm_lw_logtext()
+
+Execute (async callback error logs a WARN):
+  call delete(g:_pm_lw_log)
+  unlet g:plugin_manager_test_force_sync
+  if !plugin_manager#async#supported()
+    let g:plugin_manager_test_force_sync = 1
+    Log 'Skipping: async not supported on this Vim'
+    finish
+  endif
+  function! g:_pm_lw_cbboom(result) abort
+    throw 'async-callback-boom'
+  endfunction
+  let g:plugin_manager_max_concurrent_jobs = 1
+  " Job 1 fills the slot; job 2 queues.  Stopping the queued job runs
+  " s:process_job_completion synchronously, which invokes (and catches)
+  " the throwing callback - no event loop needed.
+  let g:_pm_lw_j1 = plugin_manager#async#start_job('sleep 5', {})
+  let g:_pm_lw_j2 = plugin_manager#async#start_job(
+        \ 'echo x', {'callback': function('g:_pm_lw_cbboom')})
+  call plugin_manager#async#stop_job(g:_pm_lw_j2)
+  call plugin_manager#async#stop_job(g:_pm_lw_j1)
+  delfunction g:_pm_lw_cbboom
+  unlet g:_pm_lw_j1 g:_pm_lw_j2
+  Assert g:_pm_lw_logtext() =~# 'async-callback-boom',
+        \ 'async callback failure must be logged, got: ' . g:_pm_lw_logtext()
+
+Execute (real helptags failure logs a WARN and is not labeled "No doc directory"):
+  call delete(g:_pm_lw_log)
+  call mkdir(g:_pm_lw_plug . '/doc', 'p')
+  " A valid help file forces :helptags to (re)write the tags file; the
+  " read-only tags file then makes the write fail with E152.
+  call writefile(['*myplugin-help*'], g:_pm_lw_plug . '/doc/myplugin.txt')
+  call writefile(['seed'], g:_pm_lw_plug . '/doc/tags')
+  call setfperm(g:_pm_lw_plug . '/doc/tags', 'r--r--r--')
+  call plugin_manager#cmd#helptags#execute(1)
+  let g:_pm_lw_sb = join(getbufline(bufnr('PluginManager'), 1, '$'), "\n")
+  Assert g:_pm_lw_sb =~# 'Helptags failed',
+        \ 'real failure must not read "No doc directory", got: ' . g:_pm_lw_sb
+  Assert g:_pm_lw_logtext() =~# 'helptags failed',
+        \ 'helptags failure must be logged, got: ' . g:_pm_lw_logtext()
+  unlet g:_pm_lw_sb
+
+Execute (local post-install exec failure logs a WARN):
+  call delete(g:_pm_lw_log)
+  " A plain existing directory path is the local-plugin input form.
+  call plugin_manager#cmd#add#execute(g:_pm_lw_local, {'exec': 'false'})
+  Assert g:_pm_lw_logtext() =~# 'post-install exec failed',
+        \ 'exec failure must be logged, got: ' . g:_pm_lw_logtext()
+
+Execute (declare invalid URL logs a WARN - synchronous path):
+  call delete(g:_pm_lw_log)
+  call plugin_manager#cmd#declare#begin()
+  call plugin_manager#cmd#declare#plugin('://nope')
+  call plugin_manager#cmd#declare#end()
+  Assert g:_pm_lw_logtext() =~# 'invalid URL format',
+        \ 'invalid URL (sync) must be logged, got: ' . g:_pm_lw_logtext()
+
+Execute (declare invalid URL logs a WARN - async batch path):
+  call delete(g:_pm_lw_log)
+  unlet g:plugin_manager_test_force_sync
+  if !plugin_manager#async#supported()
+    let g:plugin_manager_test_force_sync = 1
+    Log 'Skipping: async not supported on this Vim'
+    finish
+  endif
+  call plugin_manager#cmd#declare#begin()
+  call plugin_manager#cmd#declare#plugin('://nope')
+  call plugin_manager#cmd#declare#end()
+  let g:plugin_manager_test_force_sync = 1
+  Assert g:_pm_lw_logtext() =~# 'invalid URL format',
+        \ 'invalid URL (async batch) must be logged, got: ' . g:_pm_lw_logtext()
+
+Execute (backup git add failure logs a WARN):
+  call delete(g:_pm_lw_log)
+  call writefile(['set nocompatible'], g:_pm_lw_vimrc)
+  let g:plugin_manager_vimrc_path = g:_pm_lw_vimrc
+  call writefile(['lock'], g:_pm_lw_vim . '/.git/index.lock')
+  call plugin_manager#cmd#backup#execute()
+  call delete(g:_pm_lw_vim . '/.git/index.lock')
+  let g:plugin_manager_vimrc_path = g:_pm_lw_root . '/absent.vimrc'
+  Assert g:_pm_lw_logtext() =~# 'git add failed',
+        \ 'backup git add failure must be logged, got: ' . g:_pm_lw_logtext()
+
+Execute (removing a non-submodule dir logs a WARN when deinit fails):
+  call delete(g:_pm_lw_log)
+  call mkdir(g:_pm_lw_vim . '/pack/plugins/start/plainplugin', 'p')
+  call writefile(['x'], g:_pm_lw_vim . '/pack/plugins/start/plainplugin/a.txt')
+  call plugin_manager#cmd#remove#execute('plainplugin', '-f')
+  Assert g:_pm_lw_logtext() =~# 'deinit failed',
+        \ 'deinit failure must be logged, got: ' . g:_pm_lw_logtext()
+
+Execute (remove pointer commit failure logs a WARN and the op is not a plain "Removed"):
+  call delete(g:_pm_lw_log)
+  let $GIT_AUTHOR_NAME = ''
+  let $GIT_AUTHOR_EMAIL = ''
+  let $GIT_COMMITTER_NAME = ''
+  let $GIT_COMMITTER_EMAIL = ''
+  call plugin_manager#cmd#remove#execute('myplugin', '-f')
+  unlet $GIT_AUTHOR_NAME
+  unlet $GIT_AUTHOR_EMAIL
+  unlet $GIT_COMMITTER_NAME
+  unlet $GIT_COMMITTER_EMAIL
+  let g:_pm_lw_sb = join(getbufline(bufnr('PluginManager'), 1, '$'), "\n")
+  Assert g:_pm_lw_logtext() =~# 'pointer commit failed',
+        \ 'remove commit failure must be logged, got: ' . g:_pm_lw_logtext()
+  Assert g:_pm_lw_sb =~# 'pointer commit failed',
+        \ 'op must not claim a plain Removed, got: ' . g:_pm_lw_sb
+  unlet g:_pm_lw_sb
+
+Execute (add_submodule pointer commit failure logs a WARN and fails the add):
+  call delete(g:_pm_lw_log)
+  " Unit-level: the add#execute probe (ls-remote) is bypassed; the site
+  " under test is the discarded pointer commit in git#add_submodule.
+  let $GIT_AUTHOR_NAME = ''
+  let $GIT_AUTHOR_EMAIL = ''
+  let $GIT_COMMITTER_NAME = ''
+  let $GIT_COMMITTER_EMAIL = ''
+  let g:_pm_lw_r = plugin_manager#git#add_submodule(
+        \ 'file://' . g:_pm_lw_bare,
+        \ g:_pm_lw_vim . '/pack/plugins/start/pointerplugin',
+        \ plugin_manager#core#util#process_plugin_options([]))
+  unlet $GIT_AUTHOR_NAME
+  unlet $GIT_AUTHOR_EMAIL
+  unlet $GIT_COMMITTER_NAME
+  unlet $GIT_COMMITTER_EMAIL
+  AssertEqual 0, g:_pm_lw_r, 'pointer commit failure must fail the add'
+  Assert g:_pm_lw_logtext() =~# 'pointer commit failed',
+        \ 'add pointer commit failure must be logged, got: ' . g:_pm_lw_logtext()
+  unlet g:_pm_lw_r
+
+Execute (update with an unreachable pin target logs a WARN):
+  call delete(g:_pm_lw_log)
+  call writefile([
+        \ "Plugin 'file://" . g:_pm_lw_bare . "', {'tag': 'v-nope'}"
+        \ ], g:_pm_lw_vimrc)
+  let g:plugin_manager_vimrc_path = g:_pm_lw_vimrc
+  call plugin_manager#cmd#update#execute('myplugin')
+  let g:plugin_manager_vimrc_path = g:_pm_lw_root . '/absent.vimrc'
+  Assert g:_pm_lw_logtext() =~# 'Pin target not found',
+        \ 'pin target failure must be logged, got: ' . g:_pm_lw_logtext()
+
+Execute (stash push failure logs a WARN and does not pretend the stash exists):
+  call delete(g:_pm_lw_log)
+  " Push v2 so the module has updates, then dirty the module worktree.
+  call writefile(['v2'], g:_pm_lw_src . '/file.txt')
+  call system('git -C ' . shellescape(g:_pm_lw_src) . ' commit -aqm "v2"')
+  call system('git -C ' . shellescape(g:_pm_lw_src) . ' push -q origin HEAD:main')
+  call writefile(['dirty'], g:_pm_lw_plug . '/file.txt')
+  " Empty identity makes `git stash push` fail (it creates commits).
+  let $GIT_AUTHOR_NAME = ''
+  let $GIT_AUTHOR_EMAIL = ''
+  let $GIT_COMMITTER_NAME = ''
+  let $GIT_COMMITTER_EMAIL = ''
+  call plugin_manager#cmd#update#execute('myplugin')
+  unlet $GIT_AUTHOR_NAME
+  unlet $GIT_AUTHOR_EMAIL
+  unlet $GIT_COMMITTER_NAME
+  unlet $GIT_COMMITTER_EMAIL
+  Assert g:_pm_lw_logtext() =~# 'stash push failed',
+        \ 'stash push failure must be logged, got: ' . g:_pm_lw_logtext()
+
+Execute (auto-commit failure completes the op with a truthful warn):
+  call delete(g:_pm_lw_log)
+  let g:plugin_manager_auto_commit_on_update = 1
+  call writefile(['v3'], g:_pm_lw_src . '/file.txt')
+  call system('git -C ' . shellescape(g:_pm_lw_src) . ' commit -aqm "v3"')
+  call system('git -C ' . shellescape(g:_pm_lw_src) . ' push -q origin HEAD:main')
+  " Empty identity: the module pull (fast-forward) succeeds but the parent
+  " repo auto-commit fails.
+  let $GIT_AUTHOR_NAME = ''
+  let $GIT_AUTHOR_EMAIL = ''
+  let $GIT_COMMITTER_NAME = ''
+  let $GIT_COMMITTER_EMAIL = ''
+  call plugin_manager#cmd#update#execute('all')
+  unlet $GIT_AUTHOR_NAME
+  unlet $GIT_AUTHOR_EMAIL
+  unlet $GIT_COMMITTER_NAME
+  unlet $GIT_COMMITTER_EMAIL
+  let g:_pm_lw_sb = join(getbufline(bufnr('PluginManager'), 1, '$'), "\n")
+  Assert g:_pm_lw_logtext() =~# 'auto-commit commit failed',
+        \ 'auto-commit failure must be logged, got: ' . g:_pm_lw_logtext()
+  Assert g:_pm_lw_sb =~# 'auto-commit failed',
+        \ 'sidebar must reflect the auto-commit failure, got: ' . g:_pm_lw_sb
+  unlet g:_pm_lw_sb

From 53d07fd502f5610bf5acf5b1adb69a4a7e57c1f4 Mon Sep 17 00:00:00 2001
From: log0u7 <70974447+log0u7@users.noreply.github.com>
Date: Sun, 20 Sep 2026 01:30:24 +0200
Subject: [PATCH 2/2] test: make the helptags failure trigger root-proof for CI

Permission bits do not block root (CI containers run as root): a tags
DIRECTORY plus a valid help file makes :helptags fail with E152 for
every user.
---
 tests/log_warnings.vader | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/tests/log_warnings.vader b/tests/log_warnings.vader
index dc1a805..17c937a 100644
--- a/tests/log_warnings.vader
+++ b/tests/log_warnings.vader
@@ -164,11 +164,11 @@ Execute (async callback error logs a WARN):
 Execute (real helptags failure logs a WARN and is not labeled "No doc directory"):
   call delete(g:_pm_lw_log)
   call mkdir(g:_pm_lw_plug . '/doc', 'p')
-  " A valid help file forces :helptags to (re)write the tags file; the
-  " read-only tags file then makes the write fail with E152.
+  " A valid help file forces :helptags to (re)write the tags file; a tags
+  " DIRECTORY makes that write fail (E152) for root and users alike - CI
+  " containers run as root, so permission bits are not a usable trigger.
   call writefile(['*myplugin-help*'], g:_pm_lw_plug . '/doc/myplugin.txt')
-  call writefile(['seed'], g:_pm_lw_plug . '/doc/tags')
-  call setfperm(g:_pm_lw_plug . '/doc/tags', 'r--r--r--')
+  call mkdir(g:_pm_lw_plug . '/doc/tags', 'p')
   call plugin_manager#cmd#helptags#execute(1)
   let g:_pm_lw_sb = join(getbufline(bufnr('PluginManager'), 1, '$'), "\n")
   Assert g:_pm_lw_sb =~# 'Helptags failed',