git-remote-testgit

git-remote-testgit <command> <repository>
Note: This command is invoked internally by Git during tests, not directly by users.

capabilities
    Advertises the capabilities supported by this mock remote (e.g., fetch, push, options).

list
    Lists the references (branches, tags) available in the mock remote repository.

fetch <commit-id> <object-id>
    Simulates fetching objects from the mock remote, typically for testing fetch behavior.

push
    Handles simulated push operations, accepting or rejecting pushed refs based on test logic.

option <key> <value>
    Allows the main Git process to set specific options for the mock remote helper.

connect <service>
    Establishes a simulated connection to a specific Git service (e.g., 'git-upload-pack' for fetching, 'git-receive-pack' for pushing).

<repository>
    The URL-like string representing the mock remote repository being tested. Its content is typically ignored or used for test-specific logic by git-remote-testgit.

git-remote-testgit is an internal utility within the Git project, primarily designed to act as a mock remote helper for automated testing of Git's remote protocols. It is not intended for direct use by end-users. When Git needs to interact with a remote repository, it can invoke external "remote helper" programs (like git-remote-http or git-remote-ssh). git-remote-testgit simulates such a helper, allowing Git's test suite to verify correct behavior of commands like git clone, git fetch, and git push against a controlled, predictable, and artificial remote environment.

This utility helps developers test various scenarios, including error conditions, specific ref advertisements, and different remote capabilities, without requiring a live network connection or a real Git server. Its behavior is entirely driven by the test scripts that invoke it, making it a crucial component for ensuring the robustness and correctness of Git's network-related operations. It communicates with the main Git process via standard input/output, adhering to the well-defined Git remote helper protocol.

Not for General Use: git-remote-testgit is an internal testing tool and should never be invoked directly by users for real Git operations. Its behavior is unpredictable outside the controlled test environment.
Ephemeral and Test-Specific: The "repository" it simulates is entirely artificial and exists only for the duration of a test run. It does not persist any data.
No Public Documentation: As an internal utility, it does not have a dedicated man page or public documentation, requiring an understanding of Git's remote helper protocol to comprehend its function.

This command is crucial for Git's continuous integration and development. It enables developers to implement unit and integration tests for remote interactions, ensuring that changes to Git's core logic or remote protocols do not introduce regressions when communicating with various types of Git servers.

Like all Git remote helpers, git-remote-testgit communicates with the main Git process using a simple, text-based protocol over standard input and output. Commands are sent on stdin, and responses (e.g., lists of refs, capability advertisements) are printed to stdout. Error messages are typically sent to stderr.

git-remote-testgit has evolved as an integral part of Git's comprehensive test suite. Its development history is closely tied to the improvements and expansions of Git's remote protocol and its internal testing framework. It was introduced to provide a robust, isolated, and scriptable environment for verifying the correctness and resilience of Git's network operations, reducing reliance on external services during automated testing. It has been refined over time to support new remote capabilities and test more complex scenarios.

git-remote(1), git-remote-helpers(7), git(1)