Crate vcs_runner 

VCS-specific helpers built on procpilot. Adds jj/git shorthand wrappers, repo detection, and output parsers.

For generic subprocess execution (stdin, retry, timeout, custom envs), use procpilot::Cmd directly — it’s re-exported here for convenience.

Modules

prelude

Common types and helpers for everyday VCS subprocess work.

Structs

Bookmark

A jj bookmark with sync status.

BookmarkParseResult

Result of parsing bookmark output, including any skipped entries.

Cmd

Builder for a subprocess invocation or pipeline.

CmdDisplay

Owned snapshot of a command’s program + args, formatted shell-style on Display. For pipelines, renders each stage separated by |.

DefaultRunner

Default Runner that delegates to Cmd::run.

FileChange

A single file change in a diff summary.

GitRemote

A git remote.

JjOperation

A single entry in the jj operation log.

LogEntry

A jj log entry parsed from jj template JSON output.

LogParseResult

Result of parsing log output, including any skipped entries.

RetryPolicy

How retries are scheduled and which errors trigger them.

RunOutput

Captured output from a successful command.

SpawnedProcess

Handle to one or more spawned subprocesses (a single command or a pipeline).

Enums

ConflictState

Whether a jj commit has unresolved conflicts.

ContentState

Whether a jj commit is empty (no file changes).

FileChangeKind

The kind of change a file underwent in a diff.

Redirection

Where a child process’s stdout or stderr goes.

RemoteStatus

Sync status of a bookmark relative to its remote.

RunError

Error type for subprocess execution.

StdinData

Input data to feed to a child process’s stdin.

VcsBackend

Which version control system is managing a directory.

WorkingCopy

Whether a jj commit is the current working copy.

Constants

BOOKMARK_TEMPLATE

jj template for jj bookmark list producing line-delimited JSON.

LOG_TEMPLATE

jj template for jj log producing line-delimited JSON entries.

STREAM_SUFFIX_SIZE

Maximum bytes of stdout/stderr retained on NonZeroExit, Timeout, and Cancelled error variants. Anything beyond this is dropped from the front (FIFO), keeping the most recent output — usually the most relevant for debugging.

Traits

Runner

Pluggable backend for executing a Cmd. See the module-level docs.

Functions

binary_available

Check whether a binary is available on PATH.

binary_version

Return a binary’s --version output, if available.

default_transient

Default transient-error predicate.

detect_vcs

Detect the VCS backend for a path, without running any subprocesses.

git_available

Check whether the git binary is available on PATH.

git_merge_base

Find the merge base of two revisions in a git repository.

git_version

Get the git version string, if available.

is_transient_error

Default transient-error check for jj/git.

jj_available

Check whether the jj binary is available on PATH.

jj_current_operation_id

The id of the current (head) operation in the operation log.

jj_divergent_change_ids

Change ids that are divergent (one change id on multiple visible commits) — the persistent tell left by a concurrent op-log reconcile. Deduplicated: a change divergent across N commits is reported once. Empty means clean.

jj_is_divergent_at_operation

Whether divergent changes exist as of a specific past operation. Lets a caller walk back to the most recent operation whose state predates a divergence, to jj_op_restore to.

jj_merge_base

Find the merge base of two revisions in a jj repository.

jj_op_restore

Roll the repo back to op_id (jj op restore). The recovery primitive: pick a known-good operation instead of keeping jj’s mangled auto-merge.

jj_operation_log

The recent operation-log entries, newest first, up to limit (0 = all).

jj_revset_at_operation

The commit ids revset resolves to as of a specific operation — <ws>@ at op X, main at op X, or any revset. The building block for reconstructing a ref’s history from the operation log without parsing op log --op-diff prose (jj exposes no structured op-diff, so text-scraping is the alternative, and it is exactly the “op log is a safety net, not a tool” anti-pattern).

jj_revset_history

The distinct commit ids revset resolved to across the operation log, newest first — jj’s analog of git reflog <ref>, for any revset. The first-class replacement for scraping op log --op-diff to answer “what did this ever point at” (working-copy recovery, pre-rebase-head recovery, drift detection).

jj_version

Get the jj version string, if available.

parse_bookmark_output

Parse jj bookmark list --template BOOKMARK_TEMPLATE output.

parse_diff_summary

Parse jj diff --summary output into structured FileChange values.

parse_git_diff_name_status

Parse git diff --name-status output into structured FileChange values.

parse_log_output

Parse jj log --template LOG_TEMPLATE output.

parse_remote_list

Parse jj git remote list output into GitRemote values.

read_working_file

Read a working-tree file’s current on-disk content as text (lossy UTF-8). Ok(None) when the file is absent (e.g. deleted); Err only on a real I/O error.

read_working_file_bytes

Bytes variant of read_working_file, for image/binary handling.

run_git

Run a git command in a repo directory, returning captured output.

run_git_cancellable

Run a git command with caller-driven cancellation. See run_jj_cancellable for semantics.

run_git_utf8

Run a git command, returning lossy-decoded, trimmed stdout as a String.

run_git_utf8_cancellable

Run a git command with cancellation, returning trimmed stdout as a String.

run_git_utf8_with_retry

Run a git command with retry, returning trimmed stdout as a String.

run_git_utf8_with_retry_cancellable

Run a git command with retry + cancellation, returning trimmed stdout as a String.

run_git_utf8_with_timeout

Run a git command with a timeout, returning trimmed stdout as a String.

run_git_with_retry

Run a git command with retry on transient errors.

run_git_with_retry_cancellable

Run a git command with retry on transient errors plus caller-driven cancellation. See run_jj_with_retry_cancellable for semantics.

run_git_with_timeout

Run a git command with a timeout.

run_jj

Run a jj command in a repo directory, returning captured output.

run_jj_cancellable

Run a jj command with caller-driven cancellation.

run_jj_utf8

Run a jj command, returning lossy-decoded, trimmed stdout as a String.

run_jj_utf8_cancellable

Run a jj command with cancellation, returning trimmed stdout as a String.

run_jj_utf8_ignore_wc

Run a jj command working-copy-agnostically — with --ignore-working-copy prepended — returning lossy-decoded, trimmed stdout.

run_jj_utf8_with_retry

Run a jj command with retry, returning trimmed stdout as a String.

run_jj_utf8_with_retry_cancellable

Run a jj command with retry + cancellation, returning trimmed stdout as a String.

run_jj_utf8_with_timeout

Run a jj command with a timeout, returning trimmed stdout as a String.

run_jj_with_retry

Run a jj command with retry on transient errors.

run_jj_with_retry_cancellable

Run a jj command with retry on transient errors plus caller-driven cancellation.

run_jj_with_timeout

Run a jj command with a timeout.

working_file_is_binary

Whether a working-tree file looks binary — a NUL byte in the first 8 KiB (git’s heuristic). Reads only that prefix, so a large binary isn’t slurped in full just to be classified. Absent or unreadable ⇒ false.