Fix NaN issue in Execa by extracting .stdout

[ProchaLu]

Closes #588

The Preflight Docker container failed when trying to set the uid for the PostgreSQL setup script. The issue was that Execa returns an object, and Number() was called on the object instead of just the command output, resulting in NaN. This caused Execa to throw this error:

'The "options.uid" property must be int32. Received type number (NaN)'

It wasn’t clear why the value was NaN. We assumed that execa returned a string, but it returns an object containing the command output under .stdout. It failed because Number() was called on the entire object instead of extracting .stdout first.

const postgresUid = Number(await execa`id -u postgres`); // Fails: Execa result object → NaN

To fix this error, we need to extract .stdout before converting to a number.

const postgresUid = Number((await $`id -u postgres`).stdout); // Works: Extracts string output

ESLint didn’t catch this issue because Number({}) is currently not flagged as an error. A proposal has been made to TypeScript ESLint to introduce a rule preventing passing objects to Number().

• Rule proposal: restrict-constructor-expressions typescript-eslint/typescript-eslint#10895

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[karlhorky]

looks like the execa identifier isn't just the one imported directly from the 'execa' package, but it's this:

const projectPath = 'project-to-check';
const execa = bindExeca({ cwd: projectPath });

so probably we need to stick with using the execa identifier, or do a bigger change to switch everything to $, with this binding

[ProchaLu]

Changed to execa. cfc6c4e

[ProchaLu]

While debugging this issue, we discovered that Execa $ shorthand behaves differently depending on how it's used. Inside an Execa command, interpolation automatically extracts .stdout:

await $`dep deploy --branch=${branch}`; // Works: `branch.stdout` is extracted correctly

When assigning the result to a variable, Execa returns an object, not a string, which led to the NaN issue in our case

const branch = await $`git branch --show-current`;
console.log(branch); // Logs: [object Object]

[karlhorky]

LGTM, thanks!