How do I use Atlas to check if my prove tests are hanging in Perl?

To check if your `prove (Test2::V0)` tests are hanging, run them through Atlas's `bash` tool with a timeout, for example: `atlas bash --timeout 15000 'prove -lr t/'`. Atlas will report in the `shell_metadata` if the tests timed out due to being genuinely slow or blocked on unexpected input.

What if cpanm is silently waiting for input when I run it with Atlas?

If Atlas's `shell_metadata` indicates `cpanm` is "waiting for interactive input," it means the package manager is likely prompting for a choice. Re-run the command with non-interactive flags, such as `atlas bash 'cpanm --installdeps . --notest'` or `cpanm --force`, to bypass prompts.

Can Atlas help me debug a slow Perl script that doesn't use prove or cpanm?

Yes, Atlas can diagnose any Perl script. Just wrap its execution with `atlas bash --timeout 30000 'perl my_long_script.pl'`. Atlas will tell you if `my_long_script.pl` is genuinely slow or if it's blocked on interactive input, helping you decide whether to increase the timeout or add non-interactive flags.

How does Atlas ensure my Perl code changes are safe?

Atlas ensures safety by using a read-only plan agent, permission-gating every tool call, and presenting a unified diff for your approval before writing any changes. This applies to tasks like adding `use strict` to a `.pm` module or running `perltidy` on your files.

What if I accidentally abort a Perl command while Atlas is running it?

If you manually abort a Perl command, Atlas's `shell_metadata` output will explicitly state "User aborted the command." This clearly distinguishes your intentional interrupt from a timeout triggered by Atlas, so you know exactly why the command stopped.

Does Atlas understand Perl-specific constructs like @EXPORT lists or cpanfile?

Yes, Atlas is designed for Perl. It builds its code index by AST declarations using tree-sitter, allowing it to understand Perl-specific constructs like `@EXPORT` lists, modules pulled in by `cpanm`, and the structure of your `cpanfile` or `Makefile.PL` distributions.

Diagnose a Hanging or Long-Running Perl Command with Atlas in 2026

Atlas helps Perl developers in 2026 quickly diagnose why commands like prove (Test2::V0) or cpanm are hanging or running slowly. By wrapping your Perl commands with Atlas's bash tool, you get immediate feedback on whether a process is genuinely slow or silently blocked on interactive input, allowing you to get unstuck and continue your development workflow.

How Atlas Diagnoses Hanging Perl Commands and Scripts

Atlas provides a robust mechanism for diagnosing hanging Perl commands by wrapping them with its bash tool, which races every execution against a configurable timeout. In 2026, this means you get precise feedback within seconds, identifying whether your prove (Test2::V0) test suite or cpanm installation is genuinely slow or silently waiting for interactive input.

When you execute a Perl command through Atlas, for example, `atlas bash --timeout 10000 'prove -lr t/'`, Atlas monitors its execution. If the command exceeds the specified timeout, Atlas terminates it and provides a detailed `shell_metadata` block in its output. This metadata explicitly distinguishes between a command that was genuinely slow and one that was blocked on interactive input. This is crucial for Perl development, where a `cpanm` installation might silently prompt for a configuration choice, or a custom script might be waiting for user input without clear console feedback. Atlas's ability to index code by AST declarations using tree-sitter also helps it understand the context of your Perl modules and scripts, informing its diagnostic suggestions.

Concrete Perl Commands and Files for Diagnosis with Atlas

Diagnosing Perl commands with Atlas involves your familiar toolchain: prove (Test2::V0) for tests, cpanm for package management, and perltidy for formatting. Atlas integrates directly with these, allowing you to run commands like `atlas bash 'cpanm --installdeps .'` or `atlas bash 'perl myscript.pl'` and receive diagnostic insights within a 10-second default timeout.

Atlas works direct within your existing Perl project structure, whether it is a CPAN distribution with a `cpanfile` or `Makefile.PL`, or a simple script. To diagnose a slow `prove (Test2::V0)` run, you might use `atlas bash --timeout 30000 'prove -lr t/'`. If Atlas reports it was blocked on input, you would then re-run it with non-interactive flags if available, such as `prove --batch t/` (though `prove` is typically non-interactive, this illustrates the principle). For `cpanm`, a common scenario is `atlas bash 'cpanm Some::Module'`. If this hangs, Atlas might suggest `cpanm --notest Some::Module` or `cpanm --force Some::Module` if it detects a prompt. Atlas also reads your `.perltidyrc` for formatting, ensuring any suggested code changes align with your project's style, and can run `perltidy` on changed files after an edit.

Getting Unstuck: Retrying Perl Commands with Atlas

Once Atlas diagnoses a hanging Perl command, getting unstuck is straightforward, following one of two paths. If the command, like a complex prove (Test2::V0) test suite, is genuinely slow, you simply retry it with a larger timeout value, perhaps 60000 milliseconds. If it was blocked on interactive input, you re-run it with non-interactive flags, ensuring it cannot prompt for user interaction.

Atlas's `shell_metadata` output provides clear instructions. For instance, if `atlas bash --timeout 15000 'perl build.pl'` reports 'Command timed out. It appears to be waiting for interactive input.', you would investigate `build.pl` for prompts and re-run it with appropriate non-interactive flags, like `perl build.pl --no-input` or `perl build.pl --ci`. If the message indicates 'Command timed out. It appears to be genuinely slow.', then a simple retry with an increased timeout, such as `atlas bash --timeout 60000 'perl build.pl'`, is the solution. Atlas's ability to read `git` branches and status also means it can help you stage and commit these changes once your build or script is successfully unstuck and running as expected.

Review and Safety with Atlas in Perl Workflows

Atlas prioritizes safety and transparency in your Perl development workflow, especially when diagnosing and resolving hanging commands. Every Atlas tool call, including bash executions and file edits, is permission-gated against allow, ask, and deny rules. This ensures you maintain full control, with Atlas asking for approval before running prove -lr t/ or applying perltidy changes, often involving 2 distinct agent phases for planning and execution.

Before Atlas makes any changes to your Perl codebase, it drafts a plan in a read-only plan agent and asks for your approval. When it switches to a build agent to execute the plan, it computes a unified diff for every file edit and surfaces it for your approval before writing. This applies to scenarios like adding `use strict` and `use warnings` to a legacy Perl script or writing new `Test2::V0` cases under `t/`. Atlas also snapshots file changes as `git` patches, allowing edits to be easily diffed and rolled back if needed. This robust review process ensures that while Atlas helps you quickly diagnose and fix issues, you always have the final say over any modifications to your `.pm` modules or `cpanfile`.

Step by step

01Run your Perl command through Atlas's `bash` tool with a timeout. For example, to check a `cpanm` installation, execute `atlas bash --timeout 15000 'cpanm --installdeps .'`.
02Examine the `shell_metadata` block in Atlas's output. This block appears if the command times out or is aborted, providing a clear diagnosis.
03Decide if the Perl command is slow or blocked on input. Atlas explicitly states if the command "appears to be waiting for interactive input" or "appears to be genuinely slow."
04If blocked, re-run the Perl command with non-interactive flags. For a script `myscript.pl` that prompts, try `atlas bash 'perl myscript.pl --no-input'` or similar CI-mode flags.
05If genuinely slow, retry the Perl command with a larger timeout. For a long-running `prove (Test2::V0)` test suite, use `atlas bash --timeout 60000 'prove -lr t/'` to give it more time.
06If you manually aborted the command, verify the `shell_metadata` message. It will state "User aborted the command," distinguishing your interrupt from an Atlas timeout.

Frequently asked questions

How do I use Atlas to check if my prove tests are hanging in Perl?: To check if your `prove (Test2::V0)` tests are hanging, run them through Atlas's `bash` tool with a timeout, for example: `atlas bash --timeout 15000 'prove -lr t/'`. Atlas will report in the `shell_metadata` if the tests timed out due to being genuinely slow or blocked on unexpected input.
What if cpanm is silently waiting for input when I run it with Atlas?: If Atlas's `shell_metadata` indicates `cpanm` is "waiting for interactive input," it means the package manager is likely prompting for a choice. Re-run the command with non-interactive flags, such as `atlas bash 'cpanm --installdeps . --notest'` or `cpanm --force`, to bypass prompts.
Can Atlas help me debug a slow Perl script that doesn't use prove or cpanm?: Yes, Atlas can diagnose any Perl script. Just wrap its execution with `atlas bash --timeout 30000 'perl my_long_script.pl'`. Atlas will tell you if `my_long_script.pl` is genuinely slow or if it's blocked on interactive input, helping you decide whether to increase the timeout or add non-interactive flags.
How does Atlas ensure my Perl code changes are safe?: Atlas ensures safety by using a read-only plan agent, permission-gating every tool call, and presenting a unified diff for your approval before writing any changes. This applies to tasks like adding `use strict` to a `.pm` module or running `perltidy` on your files.
What if I accidentally abort a Perl command while Atlas is running it?: If you manually abort a Perl command, Atlas's `shell_metadata` output will explicitly state "User aborted the command." This clearly distinguishes your intentional interrupt from a timeout triggered by Atlas, so you know exactly why the command stopped.
Does Atlas understand Perl-specific constructs like @EXPORT lists or cpanfile?: Yes, Atlas is designed for Perl. It builds its code index by AST declarations using tree-sitter, allowing it to understand Perl-specific constructs like `@EXPORT` lists, modules pulled in by `cpanm`, and the structure of your `cpanfile` or `Makefile.PL` distributions.

Try Atlas in your terminal

The terminal-native AI coding agent. Free core, single binary.

Install Atlas

Related guides

Diagnose a Hanging or Long-Running Command with Atlas in 2026

How to diagnose a hanging command with Atlas in 2026: the bash tool races every command against a timeout and tells you whether it is slow or blocked on input.

Atlas for Perl: A Terminal-Native AI Coding Agent for CPAN Distributions in 2026

Atlas is a terminal-native AI coding agent for Perl in 2026. It reads cpanfile deps and @EXPORT lists, writes Test2::V0 cases, runs prove -lr t/, and runs perltidy on the diff.

Automate GitHub Issue and Pull Request Triage in Perl with Atlas in 2026

Streamline GitHub issue and pull request triage for your Perl projects in 2026 using Atlas. Automate responses safely with `cpanm`, `prove (Test2::V0)`, and `perltidy` integration, ensuring trusted user control.

Write unit tests for untested code in Perl with Atlas in 2026

In 2026, use Atlas to write unit tests for untested Perl modules. Atlas understands your cpanm dependencies and Test2::V0 conventions, ensuring new tests fit your existing codebase.

Refactor a Legacy Perl Module with Atlas in 2026

Refactor old Perl modules without breaking callers using Atlas. Map public APIs, pin behavior with prove (Test2::V0), and apply changes safely with Atlas's patch system.

Plan a Multi-File Change in Perl with Atlas in 2026

Design and review complex, multi-file Perl changes with Atlas's plan agent before modifying a single line of code. Leverage prove, cpanm, and perltidy for safe development.

Locate Perl Behavior Implementations with Atlas in 2026

Discover how Atlas helps Perl developers in 2026 pinpoint exact file and symbol locations for behaviors, leveraging semantic search, grep, and LSP across CPAN modules and TAP test suites.

Rename a symbol across the repo in Perl with Atlas in 2026

Rename Perl functions, classes, or constants across your entire codebase with Atlas in 2026. Leverage lsp, grep, and edit for precise, safe refactoring, ensuring your prove (Test2::V0) tests pass and perltidy formatting

Browse this resource hub