This resurrects the `--unstable-detect-cjs` flag (which became stable),
and repurposes it to attempt loading .js/.jsx/.ts/.tsx files as CJS in
the following additional scenarios:
1. There is no package.json
1. There is a package.json without a "type" field
Also cleans up the implementation of this in the LSP a lot by hanging
`resolution_mode()` off `Document` (didn't think about doing that until
now).
This will respect `"type": "commonjs"` in a package.json to determine if
`.js`/`.jsx`/`.ts`/.tsx` files are CJS or ESM. If the file is found to
be ESM it will be loaded as ESM though.
```
$ cat exports_error.js
Object.defineProperty(exports, "__esModule", { value: true });
$ deno exports_error.js
error: Uncaught (in promise) ReferenceError: exports is not defined
Object.defineProperty(exports, "__esModule", { value: true });
^
at file:///exports_error.js:1:23
info: Deno doesn't support CommonJS modules without `.cjs` extension.
hint: Rewrite this module to ESM or change the file extension to `.cjs`.
```
This commit adds support for executing top-level `.cjs` files,
as well as import `.cjs` files from within npm packages.
This works only for `.cjs` files, the contents of sibling `package.json`
are not consulted for the `"type"` field.
Closes https://github.com/denoland/deno/issues/25384
---------
Signed-off-by: David Sherret <dsherret@users.noreply.github.com>
Co-authored-by: Luca Casonato <hello@lcas.dev>
Co-authored-by: David Sherret <dsherret@users.noreply.github.com>
