SWE_AGENT.md always fails trying to run `gopls`

[dsyme]

I always get an error running

 develop "Add a new greeting in Swedish" | terminal

e.g. this error

failed to call interface function WorkspaceCheckable.formatFile: process "gopls format -w greetings.json" did not complete successfully: exit code: 2

I have gopls installed

dsyme@DSYME-LAPDOG:~/greetings-api$ which gopls
/usr/bin/gopls

Maybe it's trying to use this tool on a JSON file?? I'd like to debug but it's all a bit confusing since I have no idea where any of WorkspaceCheckable, formatFile or anything else is defined.

│ │ ✔ Directory.withNewFile(contents: "[\n  { \"language\": \"english\", \"greeting\": \"Hello, World!\" },\n  { \"language\": \"british\", \"greeting\": \"Hello, World! Cheers!\" },\n  { \"language\": \"french\", \"greeting\": \"Bonjour, Monde !\" },\n  { \"language\": \"italian\", \"greeting\": \"Ciao, Mondo!\" },\n  { \"language\": \"spanish\", \"greeting\": \"¡Hola, Mundo!\" },\n  { \"language\": \"german\", \"greeting\": \"Hallo, Welt!\" },\n  { \"language\": \"mandarin\", \"greeting\": \"你好，世界！\" },\n  { \"language\": \"hindi\", \"greeting\": \"नमस्ते दुनिया!\" },\n  { \"language\": \"arabic\", \"greeting\": \"مرحبا بالعالم!\" },\n  { \"language\": \"bengali\", \"greeting\": \"ওহে বিশ্ব!\" },\n  { \"language\": \"russian\", \"greeting\": \"Привет, мир!\" },\n  { \"language\": \"portuguese\", \"greeting\": \"Olá, Mundo!\" },\n  { \"language\": \"portuguese-br\", \"greeting\": \"Olá, Mundo! (Brasil)\" },\n  { \"language\": \"urdu\", \"greeting\": \"ہیلو، دنیا!\" },\n  { \"language\": \"indonesian\", \"greeting\": \"Halo Dunia!\" },\n  { \"language\": \"japanese\", \"greeting\": \"こんにちは世界！\" },\n  { \"language\": \"marathi\", \"greeting\": \"नमस्कार जग!\" },\n  { \"language\": \"telugu\", \"greeting\": \"హలో ప్రపంచం!\" }\n]", path: "greetings.json"): Directory! 0.0s
│ │
│ │ ✘ WorkspaceCheckable.formatFile(
│ │ │ │ path: "greetings.json"
│ │ │ │ source: ✔ Directory.withNewFile(contents: "[\n  { \"language\": \"english\", \"greeting\": \"Hello, World!\" },\n  { \"language\": \"british\", \"greeting\": \"Hello, World! Cheers!\" },\n  { \"language\": \"french\", \"greeting\": \"Bonjour, Monde !\" },\n  { \"language\": \"italian\", \"greeting\": \"Ciao, Mondo!\" },\n  { \"language\": \"spanish\", \"greeting\": \"¡Hola, Mundo!\" },\n  { \"language\": \"german\", \"greeting\": \"Hallo, Welt!\" },\n  { \"language\": \"mandarin\", \"greeting\": \"你好，世界！\" },\n  { \"language\": \"hindi\", \"greeting\": \"नमस्ते दुनिया!\" },\n  { \"language\": \"arabic\", \"greeting\": \"مرحبا بالعالم!\" },\n  { \"language\": \"bengali\", \"greeting\": \"ওহে বিশ্ব!\" },\n  { \"language\": \"russian\", \"greeting\": \"Привет, мир!\" },\n  { \"language\": \"portuguese\", \"greeting\": \"Olá, Mundo!\" },\n  { \"language\": \"portuguese-br\", \"greeting\": \"Olá, Mundo! (Brasil)\" },\n  { \"language\": \"urdu\", \"greeting\": \"ہیلو، دنیا!\" },\n  { \"language\": \"indonesian\", \"greeting\": \"Halo Dunia!\" },\n  { \"language\": \"japanese\", \"greeting\": \"こんにちは世界！\" },\n  { \"language\": \"marathi\", \"greeting\": \"नमस्कार जग!\" },\n  { \"language\": \"telugu\", \"greeting\": \"హలో ప్రపంచం!\" }\n]", path: "greetings.json"): Directory! 0.0s
│ │ │ ): Directory! 2.9s
│ │ ! failed to call interface function WorkspaceCheckable.formatFile: process "gopls format -w
│ │ ! greetings.json" did not complete successfully: exit code: 2
│ │ │ $ Container.withExec(args: ["go", "install", "golang.org/x/tools/gopls@latest"]): Container! 0.0s CACHED
│ │ │ ✔ .withWorkdir(path: "/app"): Container! 0.0s
│ │ │ ✔ .withDirectory(

[kpenfound]

So first to explain what's supposed to be happening:

• When the agent writes to a file in the workspace, it tries to automatically apply formatting (in this case, with gopls installed in a container) https://github.com/kpenfound/greetings-api/blob/main/.dagger/workspace/main.go#L59
• That function comes from the Checkable interface defined here: https://github.com/kpenfound/greetings-api/blob/main/.dagger/workspace/main.go#L11-L15
• The formatter with gopls is defined here: https://github.com/kpenfound/greetings-api/blob/main/.dagger/backend/main.go#L122-L137

The intent with this is that it should never fail, but apply formatting in the workspace just like your IDE would for you when you save a file. This was working last time I pushed so I'll have a look and see why gopls would fail. In the cases I tested, running it on a non-go file would be a no-op and not a failure.