Getting 'TypeError: danger.git.JSONDiffForFile is not a function'

[svenmuennich]

When running a dangerfile containing a call to danger.git.JSONDiffForFile() on peril the following error is thrown:

error: UnhandledRejection Error:  TypeError: danger.git.JSONDiffForFile is not a function
	at _callee$ (/app/danger-0.9n2i29890gp.js:62:54)
	at Object.apply (/app/node_modules/vm2/lib/contextify.js:87:36)
	at tryCatch (/app/node_modules/babel-polyfill/node_modules/regenerator-runtime/runtime.js:65:40)
	at Generator.invoke [as _invoke] (/app/node_modules/babel-polyfill/node_modules/regenerator-runtime/runtime.js:303:22)
	at tryCatch (/app/node_modules/babel-polyfill/node_modules/regenerator-runtime/runtime.js:65:40)
	at Generator.prototype.(anonymous function) [as next] (/app/node_modules/babel-polyfill/node_modules/regenerator-runtime/runtime.js:117:21)
	at invoke (/app/node_modules/babel-polyfill/node_modules/regenerator-runtime/runtime.js:155:20)
	at /app/node_modules/babel-polyfill/node_modules/regenerator-runtime/runtime.js:202:11
	at new Promise (<anonymous>)
	at callInvokeWithMethodAndArg (/app/node_modules/babel-polyfill/node_modules/regenerator-runtime/runtime.js:201:16)
/app/out/peril.js:25
throw reason;
^
TypeError: danger.git.JSONDiffForFile is not a function
	at _callee$ (/app/danger-0.9n2i29890gp.js:62:54)
	at Object.apply (/app/node_modules/vm2/lib/contextify.js:87:36)
	at tryCatch (/app/node_modules/babel-polyfill/node_modules/regenerator-runtime/runtime.js:65:40)
	at Generator.invoke [as _invoke] (/app/node_modules/babel-polyfill/node_modules/regenerator-runtime/runtime.js:303:22)
	at Generator.prototype.(anonymous function) [as next] (/app/node_modules/babel-polyfill/node_modules/regenerator-runtime/runtime.js:117:21)
	at tryCatch (/app/node_modules/babel-polyfill/node_modules/regenerator-runtime/runtime.js:65:40)
	at invoke (/app/node_modules/babel-polyfill/node_modules/regenerator-runtime/runtime.js:155:20)
	at /app/node_modules/babel-polyfill/node_modules/regenerator-runtime/runtime.js:202:11
	at new Promise (<anonymous>)
	at callInvokeWithMethodAndArg (/app/node_modules/babel-polyfill/node_modules/regenerator-runtime/runtime.js:201:16)

Here's an example dangerfile that should trigger the error.

import { danger } from 'danger';

(async function () {
    const modifiedComposerFile = danger.git.modified_files.find(file => file === 'composer.json');
    if (modifiedComposerFile) {
        const composerDiff = await danger.git.JSONDiffForFile(modifiedComposerFile);
    }
})();

Running the same dangerfile locally using the danger pr command works without error. We use the current latest commit of master (9b835cb). My local danger version is 3.8.8.

Is there any reason why JSONDiffForFile() would not be available in the object danger.git?

[orta]

Hrm, interesting, offhand - no, we have every PR running:

  const path = options.pathToPackageJSON ? options.pathToPackageJSON : "package.json"
  const packageDiff = await danger.git.JSONDiffForFile(path)

  checkForRelease(packageDiff)
  checkForLockfileDiff(packageDiff)
  checkForTypesInDeps(packageDiff)

via danger-plugin-yarn on the artsy org. What happens when you print out Object.keys(danger.git) in this case?

[svenmuennich]

The output is

[ 'modified_files', 'created_files', 'deleted_files', 'commits' ]

which looks the fields defined in the GitJSONDSL interface.

[orta]

What event is this coming from? ( wondering about #343 )

[svenmuennich]

It's a pull_request.synchronize event.

[jtreanor]

I am also seeing this issue, with the following rule:

// Podfile should not reference commit hashes
if (danger.git.modified_files.includes("Podfile")) {
    const diff = await danger.git.diffForFile("Podfile");
    if (/\+[^#]*:commit/.test(diff.added)) {
        warn("Podfile: reference to a commit hash");
    }
}

This is the error I see:

danger.git.diffForFile is not a function
TypeError: danger.git.diffForFile is not a function
    at Object.exports.default (/app/danger-0.523gif8a1eb.ts:40:39)
    at process._tickCallback (internal/process/next_tick.js:68:7)

I will look into this and post back if I find a way to solve or work around it.

[orta]

My gut is that somehow Peril thinks this run is for an event and not a PR - https://github.com/danger/peril/blob/master/api/source/github/events/github_runner.ts#L177-L192

[jtreanor]

That's an interesting thought!

If that is the case shouldn't many more things be breaking? e.g. danger.git.modified_files works fine.

[jtreanor]

Could this be some kind of configuration issue?

The Github App has Read & Write permissions for "Checks", "Issues", "Pull Requests" and "Commit Statuses". Should it also have permission for "Repository contents" or similar?

[orta]

Good guess! Repository contents could be it. This is what I use on Peril Staging. I don't think you need as much (I have no idea what people will want to build yet) but it gives a sense

[jtreanor]

Thanks, @orta.

I have tried adding just "Repository Contents" and also matching your settings (even though its overkill) and unfortunately it didn't help the issue - I restarted the Heroku app after the changes.

As with @svenmuennich, the event seems to be pull_request.synchronize. Here is the log when it happens:

2019-02-18T15:12:33.936581+00:00 app[web.1]: info:
2019-02-18T15:12:33.936714+00:00 app[web.1]: info: ## pull_request.synchronize on unknown on wordpress-mobile/WordPress-iOS
2019-02-18T15:12:33.937086+00:00 app[web.1]: info:    2 runs needed: wordpress-mobile/peril-settings@org/common.ts and wordpress-mobile/peril-settings@org/ios.ts
2019-02-18T15:12:37.646305+00:00 app[web.1]: Unable to evaluate the Dangerfile
2019-02-18T15:12:37.648992+00:00 app[web.1]: info: [runner] - Commenting, with results:
2019-02-18T15:12:37.648995+00:00 app[web.1]: mds: 1
2019-02-18T15:12:37.648997+00:00 app[web.1]: messages: 0
2019-02-18T15:12:37.648999+00:00 app[web.1]: warns: 2
2019-02-18T15:12:37.649001+00:00 app[web.1]: fails: 1
2019-02-18T15:12:37.649002+00:00 app[web.1]:
2019-02-18T15:12:38.289479+00:00 app[web.1]: Found only messages, passing those to review.
2019-02-18T15:12:39.130312+00:00 app[web.1]: Feedback: https://github.com/wordpress-mobile/WordPress-iOS/pull/10931#issuecomment-459309328

[orta]

Can you verify if danger.github.utils.fileLinks exists inside a dangerfile?

I think it's because this line in an even passes in the JSON DSL, not the full DSL (with functions etc) which would only happen if somehow Peril thinks it has an event

https://github.com/danger/peril/blob/master/api/source/runner/run.ts#L85

[jtreanor]

Yes, it does exist. I added these two lines:

console.log(`Object.keys(danger.github.utils): ${Object.keys(danger.github.utils)}`);
console.log(`Object.keys(danger.git): ${Object.keys(danger.git)}`);

And got this output:

Object.keys(danger.github.utils): fileLinks,fileContents,createUpdatedIssueWithID,createOrAddLabel,createOrUpdatePR
Object.keys(danger.git): modified_files,created_files,deleted_files,commits

[jtreanor]

I have managed to work around this issue for my particular case by changing the above rule to:

// Podfile should not reference commit hashes
const podfileContents = await danger.github.utils.fileContents("Podfile");
if (/[^#]*:commit/.test(podfileContents)) {
    warn("Podfile: reference to a commit hash");
}

Since danger.github.utils.fileContents works, I can live with this.

I'll be happy to help track this down though if there is anything I can do.

[orta]

OK, well, I think that knocks that idea out that it's the JSON version of the entire Github + git DSL being used. Tricky tricky, haven't found anything so far

[jtreanor]

Yeah, it does seem strange.

Could it be an ES6 problem since those methods are added using export interface GitDSL extends GitJSONDSL in https://github.com/danger/danger-js/blob/master/source/dsl/GitDSL.ts#L90?

I'm probably grasping at straws but its the only idea I can think of. My JS knowledge isn't very deep.