Allow resolver plugins to invalidateOnEnvChange

[tonyhallett]

🙋 feature request

Allow resolver plugins to return in result - invalidateOnEnvChange string array

🤔 Expected Behavior

In a similar manner to how other plugin types can invalidateOnEnvChange - see Config type https://parceljs.org/plugin-system/transformer/#Config

😯 Current Behavior

Cannot invalidateOnEnvChange

💁 Possible Solution

ResolverRunner resolve

    let invalidateOnFileCreate = [];
    let invalidateOnFileChange = [];
    let invalidateOnEnvChange = [];//************************** and ensure that it available in the returned object
    for (let resolver of resolvers) {
      try {
        let result = await resolver.plugin.resolve({
          specifier,
          pipeline,
          dependency: dep,
          options: this.pluginOptions,
          logger: new PluginLogger({origin: resolver.name}),
        });

        if (result) {
          if (result.meta) {
            dependency.resolverMeta = result.meta;
            dependency.meta = {
              ...dependency.meta,
              ...result.meta,
            };
          }

          if (result.priority != null) {
            dependency.priority = Priority[result.priority];
          }

          if (result.invalidateOnFileCreate) {
            invalidateOnFileCreate.push(...result.invalidateOnFileCreate);
          }

          if (result.invalidateOnFileChange) {
            invalidateOnFileChange.push(...result.invalidateOnFileChange);
          }

          if (result.invalidateOnEnvChange ) { // *********************
            invalidateOnEnvChange .push(...result.invalidateOnEnvChange );
          }

PathRequest after ResolverRunner

async function run({input, api, options}: RunOpts) {
  let configResult = nullthrows(
    await api.runRequest<null, ConfigAndCachePath>(createParcelConfigRequest()),
  );
  let config = getCachedParcelConfig(configResult, options);
  let resolverRunner = new ResolverRunner({
    options,
    config,
  });
  let result: ResolverResult = await resolverRunner.resolve(input.dependency);

  if (result.invalidateOnEnvChange) { //***************************************************
    for (let env of result.invalidateOnEnvChange) {
      api.invalidateOnEnvChange(env);
    }
  }

🔦 Context

I have created a Resolver that aliases through an environment variable instead of package.json.
I would like to invalidateOnEnvChange.

💻 Examples

(https://gist.github.com/bvaughn/25e6233aeb1b4f0cdb8d8366e54a3977?permalink_comment_id=4166747#gistcomment-4166747)

[mischnic]

Could you open a PR with your changes? That looks good to me, we just need a test case.

[tonyhallett]

@mischnic I will create a pull request in the coming days