Add the handle-pr-comment GitHub Action

This is the culmination of all the preparation: The first GitHub Action
that will be used in a GitHub workflow that will replace these trusty
Azure Pipelines we used for so long:

  - GitGitGadget PR Handler:
    https://dev.azure.com/gitgitgadget/git/_build?definitionId=3

  - GitGitGadget PR Handler (git):
    https://dev.azure.com/gitgitgadget/git/_build?definitionId=13

  - GitGitGadget PR Handler (dscho):
    https://dev.azure.com/gitgitgadget/git/_build?definitionId=12

Note that this Action receives the full `pr-comment-url` as Action
input; Readers might wonder why the Action cannot receive the
information in a more fine-grained manner, seeing as the `github`
context of a GitHub workflow triggered by a new PR comment already has
all the necessary values. But this would require adding a
GitGitGadget-specific workflow to the main `git/git` repository,
something that was considered in
gitgitgadget/gitgitgadget#861 but which would
be _extremely_ difficult to convince the core Git contributors to
accept. Therefore, the GitHub workflow using this Action will be a
`workflow_dispatch`-triggered one, for more details see
gitgitgadget-workflows/gitgitgadget-workflows#1.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

Author: dscho

handle-pr-comment/action.yml

@@ -0,0 +1,34 @@
+name: 'Handle PR Comment'
+description: 'Handles slash commands such as /submit and /preview'
+author: 'Johannes Schindelin'
+inputs:
+  pr-repo-token:
+    description: 'The access token to work on the repository that holds PRs and state'
+    required: true
+  upstream-repo-token:
+    description: 'The access token to work on PRs in the upstream repository'
+    required: true
+  test-repo-token:
+    description: 'The access token to work on PRs in the test repository'
+    required: true
+  smtp-host:
+    description: 'The SMTP host to use for sending emails'
+    required: true
+  smtp-user:
+    description: 'The SMTP user when sending emails'
+    required: true
+  smtp-opts:
+    description: 'Extra SMTP options in JSON format'
+    required: false
+  smtp-pass:
+    description: 'The SMTP password to use for sending emails'
+    required: true
+  pr-comment-url:
+    description: 'The URL of the PR comment to add a reaction to'
+    required: true
+runs:
+  using: 'node20'
+  main: './index.js'
+branding:
+  icon: 'git-commit'
+  color: 'orange'

handle-pr-comment/index.js

@@ -0,0 +1,11 @@
+async function run() {
+  const { CIHelper } = await import("../dist/index.js")
+
+  const ci = new CIHelper()
+  const { owner, commentId } = ci.parsePRCommentURLInput()
+
+  await ci.setupGitHubAction()
+  await ci.handleComment(owner, commentId)
+}
+
+run()

package.json

@@ -14,7 +14,7 @@
     "build": "tsc",
     "build-dist": "ncc build -s -m ./lib/ci-helper.ts -o dist",
     "cleanbranch": "node ./build/script/delete-test-branches.js",
-    "lint": "eslint \"{lib,script,tests,tests-config}/**/*.{ts,tsx,mjs,js}\" --ignore-pattern \"dist/**/*\"",
+    "lint": "eslint \"{lib,script,tests,tests-config}/**/*.{ts,tsx,mjs,js}\" \"*/index.js\" --ignore-pattern \"dist/**/*\"",
     "start": "node server.js",
     "test": "node --experimental-vm-modules node_modules/jest/bin/jest.js --env=node",
     "test:clean": "jest --clearCache && npm test",