ZSH Completion Script incorrect

[MarcoEidinger]

Description

Trying to use auto-completion for swift package (or other SwiftPM commands) relying on completion script generated with swift package completion-tool generate-zsh-script

Expected behavior

Code completion appears

Actual behavior

Getting parsing error when trying code completion

Steps to reproduce

Run the commands as noted in https://github.com/apple/swift-package-manager/blob/main/Documentation/Usage.md#using-shell-completion-scripts

mkdir ~/.zsh
swift package completion-tool generate-zsh-script > ~/.zsh/_swift
echo -e "fpath=(~/.zsh \$fpath)\n" >> ~/.zshrc
compinit

Then open new terminal and try auto-complete (TAB) for swift package

Swift Package Manager version/commit hash

Swift 5.6.1 (Xcode 13.4.1)

Swift & OS version (output of swift --version && uname -a)

swift-driver version: 1.45.2 Apple Swift version 5.6.1 (swiftlang-5.6.0.323.66 clang-1316.0.20.12)
Target: arm64-apple-macosx12.0

[tomerd]

@bitjammer is this something you are familiar with?

[neonichu]

We're just calling ParsableArguments.completionScript(for:) from argument parser for this, btw.

[rauhul]

If you could reduce this to a small reproducer and open an issue in apple/swift-argument-parser we can take a look!

[MarcoEidinger]

It appears that using an empty string as a value for commandName in DefaultCommand causes the issue.

swift-package-manager/Sources/Commands/SwiftPackageTool.swift

Line 1480 in 6aff18f

commandName: "",

In my small reproducer (https://github.com/MarcoEidinger/spm-issue-5789-repo) I find no issues when using commandName: nil,

@rauhul please advise if you see this as issue for apple/swift-argument-parser and I should create an issue there OR if you think that SPM shall change their implementation

FYI @neonichu

[rauhul]

Looks like a sap bug imo, though the quick solution for spm is changing the default to nil. I can probably fix the sap issue tomorrow morning, but filing an issue would be good regardless!

Thanks a ton for tracking down the bug 💛

[MarcoEidinger]

I created PR to change SPM for an easy solution.

SPM is using swift-argument-parser@1.0.3

@rauhul further testing reveals that this particular issue is solved in swift-argument-parser@1.1.4 due to apple/swift-argument-parser#443 which filters out subcommands that shall not be displayed which would be the case for SPM's DefaultCommand

extension SwiftPackageTool {
    // This command is the default when no other subcommand is passed. It is not shown in the help and is never invoked directly.
    struct DefaultCommand: SwiftCommand {
        static let configuration = CommandConfiguration(
            commandName: "",
            shouldDisplay: false) // <====!!!!!!!!!!!
         }
     }
}

Hence I won't file an issue in swift-argument-parser

[rauhul]

I think this is still reveals a bug in sap as we should never generate illegal completion scripts.