Provide platform-specific hint for poetry shell #10177

[daviewales]

Pull Request Check List

Resolves: #10177

• Added tests for changed code.
• Updated documentation for changed code.

I'm not sure if this needs a documentation change.
Let me know if it needs a test and I'll add one.

[sourcery-ai]

Reviewer's Guide by Sourcery

This pull request introduces a new feature that provides shell-specific hints to the user when the poetry shell command fails. This helps users activate the Poetry environment correctly based on their shell.

Sequence diagram for poetry shell command with shell detection and hint

sequenceDiagram
  participant User
  participant PoetryApplication
  participant Shellingham
  participant IO

  User->>PoetryApplication: Runs `poetry shell`
  PoetryApplication->>Shellingham: detect_shell()
  alt Shell detected
    Shellingham-->>PoetryApplication: Shell name (e.g., bash)
    PoetryApplication->>PoetryApplication: Determines activation command based on shell
    PoetryApplication->>IO: Writes error message and activation hint
    IO-->>User: Displays error and hint
  else Shell detection fails
    Shellingham-->>PoetryApplication: ShellDetectionFailure
    PoetryApplication->>IO: Writes error message without hint
    IO-->>User: Displays error
  end

Loading

File-Level Changes

Change	Details	Files
Added a function to provide shell-specific hints for activating the Poetry environment.	Introduced env_activate_hint() function to detect the user's shell. Based on the detected shell, the function returns the appropriate command to activate the Poetry environment. The function returns None if the shell is not supported. The env_activate_hint function uses the shellingham library to detect the shell. Added logic to display the hint when the shell command fails. The hint is displayed only when the shell command is invoked and an environment activation hint is available.	src/poetry/console/application.py

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[sourcery-ai]

Hey @daviewales - I've reviewed your changes - here's some feedback:

Overall Comments:

• Consider adding a fallback mechanism if shellingham fails to detect the shell, perhaps prompting the user to manually specify their shell type.

Here's what I looked at during the review

• 🟡 General issues: 1 issue found
• 🟢 Security: all looks good
• 🟢 Testing: all looks good
• 🟡 Complexity: 1 issue found
• 🟢 Documentation: all looks good

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[sourcery-ai]

question (bug_risk): Double-check the activation command syntax for fish and elvish.

Make sure that the command syntax used here is correct for fish/elvish shells, as they might have specific requirements or variations from other shells.

[daviewales]

I checked this. I would appreciate a human double-checking the command syntax however.

[sourcery-ai]

issue (complexity): Consider using a dictionary to map shells to activation commands for improved readability and maintainability.

def env_activate_hint() -> str | None:
    try:
        import shellingham
        shell = shellingham.detect_shell()[0]
    except shellingham.ShellDetectionFailure:
        shell = None

    shell_commands = {
        "sh": "eval $(poetry env activate)",
        "bash": "eval $(poetry env activate)",
        "dash": "eval $(poetry env activate)",
        "ash": "eval $(poetry env activate)",
        "zsh": "eval $(poetry env activate)",
        "ksh": "eval $(poetry env activate)",
        "xonsh": "eval $(poetry env activate)",
        "csh": "eval `poetry env activate`",
        "tcsh": "eval `poetry env activate`",
        "fish": "eval (poetry env activate)",
        "elvish": "eval (poetry env activate)",
        "powershell": "Invoke-Expression (poetry env activate)",
        "pwsh": "Invoke-Expression (poetry env activate)",
    }

    env_activate_command = shell_commands.get(shell)

    if env_activate_command:
        return (
            f"<b>HINT</b>: Your shell appears to be {shell}. You probably need this command:\n\n"
            f"<c1>{env_activate_command}</>"
        )
    return None

Actionable Steps:

1. Replace the multiple if/elif branches with a mapping (shell_commands) to associate shells with commands.
2. Use the get method on the dictionary to retrieve the command based on shell, which reduces duplicate logic and improves maintainability.

These changes keep functionality intact while simplifying the code logic.

[daviewales]

I'm not convinced that this is better. There is a lot of duplication in the dictionary version. You could deduplicate the dictionary with variables, but I think the if-else approach is OK.

[sourcery-ai]

Thank you for your feedback, we will generate fewer comments like this in the future.

[daviewales]

A fall-back is not necessary, because this is an extension to the existing help message. It automatically falls back to the existing message if the shell is not detected.

[Secrus]

I don't like it. I was against having the previous help message about shell command too. If another maintainer accepts this, I won't block it, but I won't approve it myself.