Better performance for --showdescription

Currently it’s taking between 4 and 5 seconds. Is there anything that can be done about that? Ideally there would be some way to get it under 500ms.

I added target name autocomplete to my bootstrapper which executes --showdescription, but it freezes the console for 4-5 seconds every time I press tab. 200ms would be so cool though…

I know Cake takes a while to check dependencies and compile, but no one ever creates targets that only conditionally appear, so in my mind we wouldn’t even have to compile the script to obtain the list of calls to Target. But if you wanted to be absolutely completely safe, the --showdescription logic could look like this:

1. Parse the script file’s syntax
2. Locate all usages of the name Target
3. If every usage of Target is a call with a literal string name and the call is not nested under a conditional, add it to the list. Otherwise, finish compiling the script and discover the list the old way.

I’m pretty sure the fallback will never actually be needed though.

[devlead]

Currently it’ll codgen, reference dependencies, compile and execute the C# code. for it to be 200ms likely would have to not do that but rather some specific --showdescription parsing code.

Unsure if this is a a high priority or worth it at the moment, a potential work around would be to in boostrapper use powershell to extract the needed info i.e. something like

[string[]] $tasks = Get-Content .\build.cake|Select-String -Pattern 'Task\("(.*?)"\)' | % Matches | % {$_.Groups[1].Value}

that takes around 8 ms on my machine on cake’s build.cake, resulting in an array containing

Clean
Restore-NuGet-Packages
Build
Run-Unit-Tests
Copy-Files
Zip-Files
Create-Chocolatey-Packages
Create-NuGet-Packages
Sign-Binaries
Upload-AppVeyor-Artifacts
Upload-Coverage-Report
Publish-MyGet
Publish-NuGet
Publish-Chocolatey
Publish-HomeBrew
Publish-GitHub-Release
Create-Release-Notes
Package
Default
AppVeyor
Travis
ReleaseNotes

where it would fail would be if tasks are defined in any other file external to take i.e. included via #load which is one of the complexities as some files make be located in nuget packages needed to be fetched an loaded.

[jnm2]

It this was tracking work that you still want to do, please feel free to reopen! Otherwise, cleaning up due to inactivity.