Return repo information if the index is unreadable

gitstatus.plugin.sh

@@ -352,6 +352,7 @@ function gitstatus_stop() {
 #                                   Non-negative integer.
 #   VCS_STATUS_NUM_ASSUME_UNCHANGED The number of files in the index with assume-unchanged bit set.
 #                                   Non-negative integer.
+#   VCS_STATUS_INDEX_DISABLED       Either the -p option was set or the index could not be read.
 #
 # The point of reporting -1 via VCS_STATUS_HAS_* is to allow the command to skip scanning files in
 # large repos. See -m flag of gitstatus_start.
@@ -418,6 +419,7 @@ function gitstatus_query() {
     VCS_STATUS_NUM_ASSUME_UNCHANGED="${resp[26]:-0}"
     VCS_STATUS_COMMIT_ENCODING="${resp[27]-}"
     VCS_STATUS_COMMIT_SUMMARY="${resp[28]-}"
+    VCS_STATUS_INDEX_DISABLED="${resp[29]-}"
     VCS_STATUS_HAS_STAGED=$((VCS_STATUS_NUM_STAGED > 0))
     if (( _GITSTATUS_DIRTY_MAX_INDEX_SIZE >= 0 &&
           VCS_STATUS_INDEX_SIZE > _GITSTATUS_DIRTY_MAX_INDEX_SIZE_ )); then

gitstatus.plugin.zsh

@@ -43,6 +43,7 @@
 #   VCS_STATUS_STASHES=0
 #   VCS_STATUS_TAG=''
 #   VCS_STATUS_WORKDIR=/home/romka/powerlevel10k
+#   VCS_STATUS_INDEX_DISABLED=0
 
 [[ -o 'interactive' ]] || 'return'
 
@@ -347,7 +348,8 @@ function _gitstatus_process_response"${1:-}"() {
           VCS_STATUS_NUM_SKIP_WORKTREE    \
           VCS_STATUS_NUM_ASSUME_UNCHANGED \
           VCS_STATUS_COMMIT_ENCODING      \
-          VCS_STATUS_COMMIT_SUMMARY in "${(@)resp[3,29]}"; do
+          VCS_STATUS_COMMIT_SUMMARY       \
+          VCS_STATUS_INDEX_DISABLED in "${(@)resp[3,30]}"; do
       done
       typeset -gi VCS_STATUS_{INDEX_SIZE,NUM_STAGED,NUM_UNSTAGED,NUM_CONFLICTED,NUM_UNTRACKED,COMMITS_AHEAD,COMMITS_BEHIND,STASHES,NUM_UNSTAGED_DELETED,NUM_STAGED_NEW,NUM_STAGED_DELETED,PUSH_COMMITS_AHEAD,PUSH_COMMITS_BEHIND,NUM_SKIP_WORKTREE,NUM_ASSUME_UNCHANGED}
       typeset -gi VCS_STATUS_HAS_STAGED=$((VCS_STATUS_NUM_STAGED > 0))

src/gitstatus.cc

@@ -106,7 +106,7 @@ void ProcessRequest(const Options& opts, RepoCache& cache, Request req) {
   // Repository state, A.K.A. action. For example, "merge".
   resp.Print(RepoState(repo->repo()));
 
-  IndexStats stats;
+  IndexStats stats {.disabled = true};
   // Look for staged, unstaged and untracked. This is where most of the time is spent.
   if (req.diff) stats = repo->GetIndexStats(head_target, cfg);
 
@@ -176,6 +176,9 @@ void ProcessRequest(const Options& opts, RepoCache& cache, Request req) {
   resp.Print(msg.encoding);
   resp.Print(msg.summary);
 
+  // 1 if index computation disabled by req or we could not read the index, 0 otherwise
+  resp.Print(stats.disabled);
+
   resp.Dump("with git status");
 }
 

src/options.cc

@@ -184,6 +184,7 @@ void PrintUsage() {
             << "    27. Number of files in the index with assume-unchanged bit set.\n"
             << "    28. Encoding of the HEAD's commit message. Empty value means UTF-8.\n"
             << "    29. The first paragraph of the HEAD's commit message as one line.\n"
+            << "    30. 1 if index was not read, 0 otherwise.\n"
             << "\n"
             << "Note: Renamed files are reported as deleted plus new.\n"
             << "\n"
@@ -228,6 +229,7 @@ void PrintUsage() {
             << "    '0'\n"
             << "    ''\n"
             << "    'add a build server for darwin-arm64'\n"
+            << "    '0'\n"
             << "\n"
             << "EXIT STATUS\n"
             << "\n"

src/repo.cc

@@ -152,7 +152,10 @@ IndexStats Repo::GetIndexStats(const git_oid* head, git_config* cfg) {
       index_.reset();
     }
   } else {
-    VERIFY(!git_repository_index(&git_index_, repo_)) << GitError();
+    if (git_repository_index(&git_index_, repo_)) {
+      // Can't read index, proceed as if index computations are disabled
+      return {.disabled = true};
+    }
     // Query an attribute (doesn't matter which) to initialize repo's attribute
     // cache. It's a workaround for synchronization bugs (data races) in libgit2
     // that result from lazy cache initialization without synchronization.
@@ -239,7 +242,8 @@ IndexStats Repo::GetIndexStats(const git_oid* head, git_config* cfg) {
           .num_staged_deleted = std::min(Load(staged_deleted_), num_staged),
           .num_unstaged_deleted = std::min(Load(unstaged_deleted_), num_unstaged),
           .num_skip_worktree = Load(skip_worktree_),
-          .num_assume_unchanged = Load(assume_unchanged_)};
+          .num_assume_unchanged = Load(assume_unchanged_),
+          .disabled = false};
 }
 
 int Repo::OnDelta(const char* type, const git_diff_delta& d, std::atomic<size_t>& c1, size_t m1,

src/repo.h

@@ -58,6 +58,7 @@ struct IndexStats {
   size_t num_unstaged_deleted = 0;
   size_t num_skip_worktree = 0;
   size_t num_assume_unchanged = 0;
+  bool disabled = false;
 };
 
 class Repo {