Add Repository::in_progress_operation()

.github/workflows/ci.yml

@@ -39,7 +39,7 @@ jobs:
       - name: Setup dependencies (macos)
         if: startsWith(matrix.os, 'macos')
         run:
-          brew install tree openssl
+          brew install tree openssl gnu-sed
       - name: "cargo check default features"
         if: startsWith(matrix.os, 'windows')
         uses: actions-rs/cargo@v1

git-repository/src/lib.rs

@@ -192,7 +192,9 @@ pub enum Path {
 
 ///
 mod types;
-pub use types::{Commit, DetachedObject, Head, Id, Object, Reference, Repository, Tag, ThreadSafeRepository, Tree};
+pub use types::{
+    Commit, DetachedObject, Head, Id, Object, Reference, Repository, RepositoryState, Tag, ThreadSafeRepository, Tree,
+};
 
 pub mod commit;
 pub mod head;

git-repository/src/repository/mod.rs

@@ -136,6 +136,8 @@ mod location;
 
 mod snapshots;
 
+mod state;
+
 mod impls;
 
 mod cache;

git-repository/src/repository/state.rs

@@ -0,0 +1,42 @@
+use crate::RepositoryState;
+
+impl crate::Repository {
+    /// Returns the status of an in progress operation on a repository or [`None`]
+    /// if nothing is happening.
+    pub fn in_progress_operation(&self) -> Option<RepositoryState> {
+        let git_dir = self.path();
+
+        // This is modeled on the logic from wt_status_get_state in git's wt-status.c and
+        // ps1 from git-prompt.sh.
+
+        if git_dir.join("rebase-apply/applying").is_file() {
+            Some(RepositoryState::ApplyMailbox)
+        } else if git_dir.join("rebase-apply/rebasing").is_file() {
+            Some(RepositoryState::Rebase)
+        } else if git_dir.join("rebase-apply").is_dir() {
+            Some(RepositoryState::ApplyMailboxRebase)
+        } else if git_dir.join("rebase-merge/interactive").is_file() {
+            Some(RepositoryState::RebaseInteractive)
+        } else if git_dir.join("rebase-merge").is_dir() {
+            Some(RepositoryState::Rebase)
+        } else if git_dir.join("CHERRY_PICK_HEAD").is_file() {
+            if git_dir.join("todo").is_file() {
+                Some(RepositoryState::CherryPickSequence)
+            } else {
+                Some(RepositoryState::CherryPick)
+            }
+        } else if git_dir.join("MERGE_HEAD").is_file() {
+            Some(RepositoryState::Merge)
+        } else if git_dir.join("BISECT_LOG").is_file() {
+            Some(RepositoryState::Bisect)
+        } else if git_dir.join("REVERT_HEAD").is_file() {
+            if git_dir.join("todo").is_file() {
+                Some(RepositoryState::RevertSequence)
+            } else {
+                Some(RepositoryState::Revert)
+            }
+        } else {
+            None
+        }
+    }
+}

git-repository/src/types.rs

@@ -124,6 +124,31 @@ pub struct Repository {
     pub(crate) config: crate::config::Cache,
 }
 
+/// The state of a git repository
+#[derive(Debug, PartialEq)]
+pub enum RepositoryState {
+    /// Apply mailbox in progress
+    ApplyMailbox,
+    /// Rebase while an apply mailbox operation is in progress
+    ApplyMailboxRebase,
+    /// Bisect in progress
+    Bisect,
+    /// Cherry pick operation in progress
+    CherryPick,
+    /// Cherry pick with multiple commits pending in the sequencer in progress
+    CherryPickSequence,
+    /// Merge operation in progress
+    Merge,
+    /// Rebase in progress
+    Rebase,
+    /// Interactive rebase in progress
+    RebaseInteractive,
+    /// Revert operation in progress
+    Revert,
+    /// Revert operation with multiple commits pending in the sequencer in progress
+    RevertSequence,
+}
+
 /// An instance with access to everything a git repository entails, best imagined as container implementing `Sync + Send` for _most_
 /// for system resources required to interact with a `git` repository which are loaded in once the instance is created.
 ///

git-repository/tests/fixtures/make_cherry_pick_repo.sh

@@ -0,0 +1,31 @@
+#!/bin/bash
+set -eu -o pipefail
+
+git init -q
+
+git config commit.gpgsign false
+
+git config advice.statusHints false
+git config advice.resolveConflict false
+git config advice.commitBeforeMerge false
+git config advice.skippedCherryPicks false
+
+git config init.defaultBranch master
+
+unset GIT_AUTHOR_DATE
+unset GIT_COMMITTER_DATE
+
+touch 1
+git add 1
+git commit -m 1 1
+git checkout -b other-branch
+echo other-branch > 1
+git add 1
+git commit -m 1.other 1
+git checkout master
+echo master > 1
+git add 1
+git commit -m 1.master 1
+
+# This should fail and leave us in a cherry-pick state
+git cherry-pick other-branch || true

git-repository/tests/fixtures/make_rebase_i_repo.sh

@@ -0,0 +1,41 @@
+#!/bin/bash
+set -eu -o pipefail
+
+git init -q
+
+git config commit.gpgsign false
+
+git config advice.statusHints false
+git config advice.resolveConflict false
+git config advice.commitBeforeMerge false
+git config advice.skippedCherryPicks false
+
+git config init.defaultBranch master
+
+unset GIT_AUTHOR_DATE
+unset GIT_COMMITTER_DATE
+
+touch 1 2 3
+git add 1
+git commit -m 1 1
+git add 2
+git commit -m 2 2
+git add 3
+git commit -m 3 3
+
+# NOTE: This relies on GNU sed behavior and will fail on *BSDs (including macOS) without GNU
+# sed installed.  
+sed=$(which gsed sed | head -1 || true)
+
+# GNU sed recognizes long arguments, BSD sed does not
+# NOTE: We can't rely on $? because set -e guarantees the script will terminate on a non-zero exit
+${sed} --version 2&>/dev/null && sed_exit_code=success || sed_exit_code=fail
+if [ "${sed_exit_code}" = "fail" ]; then
+  printf "\n** GNU sed is required for this test but was not found **\n"
+  exit 1
+fi
+unset sed_exit_code
+
+# NOTE: Starting around git 2.35.0 --preserve-merges was renamed to --rebase-merges
+# however --preserve-merges first appeared in git 2.18.  That should cover most use cases.
+EDITOR="${sed} -i.bak -z 's/pick/edit/2'" git rebase --rebase-merges --interactive HEAD~2

git-repository/tests/fixtures/make_revert_repo.sh

@@ -0,0 +1,25 @@
+#!/bin/bash
+set -eu -o pipefail
+
+git init -q
+
+git config commit.gpgsign false
+
+git config advice.statusHints false
+git config advice.resolveConflict false
+git config advice.commitBeforeMerge false
+git config advice.skippedCherryPicks false
+
+git config init.defaultBranch master
+
+unset GIT_AUTHOR_DATE
+unset GIT_COMMITTER_DATE
+
+touch 1 2 3
+git add 1
+git commit -m 1 1
+git add 2
+git commit -m 2 2
+git add 3
+git commit -m 3 3
+git revert --no-commit HEAD~1

git-repository/tests/repo.rs

@@ -27,3 +27,4 @@ mod discover;
 mod easy;
 mod init;
 mod reference;
+mod state;

git-repository/tests/state/mod.rs

@@ -0,0 +1,54 @@
+use crate::{repo, Result};
+use anyhow::anyhow;
+use git_repository::{bstr::ByteSlice, RepositoryState};
+
+// Can we identify that a cherry pick operation is in progress
+#[test]
+fn cherry_pick() -> Result {
+    let repo = repo("make_cherry_pick_repo.sh").map(|r| r.to_thread_local())?;
+
+    let head = repo.head()?;
+    let head_name = head
+        .referent_name()
+        .ok_or_else(|| anyhow!("detached head?"))?
+        .shorten()
+        .to_str()?;
+    assert_eq!("master", head_name);
+
+    assert_eq!(Some(RepositoryState::CherryPick), repo.in_progress_operation());
+
+    Ok(())
+}
+
+// Can we identify that we're in the middle of an interactive rebase?
+#[test]
+fn rebase_interactive() -> Result {
+    let repo = repo("make_rebase_i_repo.sh").map(|r| r.to_thread_local())?;
+
+    let head = repo.head()?;
+    // TODO: Get rebase head/target
+    let head_name = head.referent_name();
+    assert!(head_name.is_none());
+
+    assert_eq!(Some(RepositoryState::RebaseInteractive), repo.in_progress_operation());
+
+    Ok(())
+}
+
+// Can we identify a revert operation when we see it?
+#[test]
+fn revert() -> Result {
+    let repo = repo("make_revert_repo.sh").map(|r| r.to_thread_local())?;
+
+    let head = repo.head()?;
+    let head_name = head
+        .referent_name()
+        .ok_or_else(|| anyhow!("detached head?"))?
+        .shorten()
+        .to_str()?;
+    assert_eq!("master", head_name);
+
+    assert_eq!(Some(RepositoryState::Revert), repo.in_progress_operation());
+
+    Ok(())
+}