feat(sync): leave comment with changes

docs/api/cautious-journey.githubremote.createcomment.md

@@ -7,9 +7,16 @@
 <b>Signature:</b>
 
 ```typescript
-createComment(): Promise<void>;
+createComment(options: CommentUpdate): Promise<unknown>;
 ```
+
+## Parameters
+
+|  Parameter | Type | Description |
+|  --- | --- | --- |
+|  options | CommentUpdate |  |
+
 <b>Returns:</b>
 
-Promise&lt;void&gt;
+Promise&lt;unknown&gt;
 

docs/api/cautious-journey.githubremote.formatbody.md

@@ -0,0 +1,22 @@
+<!-- Do not edit this file. It is automatically generated by API Documenter. -->
+
+[Home](./index.md) &gt; [cautious-journey](./cautious-journey.md) &gt; [GithubRemote](./cautious-journey.githubremote.md) &gt; [formatBody](./cautious-journey.githubremote.formatbody.md)
+
+## GithubRemote.formatBody() method
+
+<b>Signature:</b>
+
+```typescript
+formatBody(options: CommentUpdate): string;
+```
+
+## Parameters
+
+|  Parameter | Type | Description |
+|  --- | --- | --- |
+|  options | CommentUpdate |  |
+
+<b>Returns:</b>
+
+string
+

docs/api/cautious-journey.githubremote.md

@@ -33,9 +33,10 @@ export declare class GithubRemote implements Remote
 |  Method | Modifiers | Description |
 |  --- | --- | --- |
 |  [connect()](./cautious-journey.githubremote.connect.md) |  |  |
-|  [createComment()](./cautious-journey.githubremote.createcomment.md) |  |  |
+|  [createComment(options)](./cautious-journey.githubremote.createcomment.md) |  |  |
 |  [createLabel(options)](./cautious-journey.githubremote.createlabel.md) |  |  |
 |  [deleteLabel(options)](./cautious-journey.githubremote.deletelabel.md) |  |  |
+|  [formatBody(options)](./cautious-journey.githubremote.formatbody.md) |  |  |
 |  [getIssue()](./cautious-journey.githubremote.getissue.md) |  |  |
 |  [getLabel()](./cautious-journey.githubremote.getlabel.md) |  |  |
 |  [listIssues(options)](./cautious-journey.githubremote.listissues.md) |  |  |

src/remote/github.ts

@@ -2,7 +2,9 @@ import { doesExist, InvalidArgumentError, mustExist, NotImplementedError } from
 import { createAppAuth } from '@octokit/auth-app';
 import { Octokit } from '@octokit/rest';
 
-import { IssueUpdate, LabelQuery, LabelUpdate, ProjectQuery, Remote, RemoteOptions } from '.';
+import { CommentUpdate, IssueUpdate, LabelQuery, LabelUpdate, ProjectQuery, Remote, RemoteOptions } from '.';
+import { ChangeVerb } from '../resolve';
+import { VERSION_INFO } from '../version';
 
 /**
  * Github/Octokit API implementation of the `Remote` contract.
@@ -17,8 +19,7 @@ export class GithubRemote implements Remote {
 
   constructor(options: RemoteOptions) {
     this.options = options;
-
-    options.logger.debug(options, 'github remote');
+    this.options.logger.debug(options, 'created github remote');
   }
 
   public async connect() {
@@ -60,8 +61,27 @@ export class GithubRemote implements Remote {
     };
   }
 
-  public async createComment() {
-    throw new NotImplementedError();
+  public async createComment(options: CommentUpdate): Promise<unknown> {
+    const path = await this.splitProject(options.project);
+    const body = this.formatBody(options);
+
+    this.options.logger.debug({
+      body,
+      issue: options.issue,
+      project: options.project,
+    }, 'creating issue comment');
+
+    if (this.writeCapable) {
+      await this.writeRequest.issues.createComment({
+        body,
+        /* eslint-disable-next-line camelcase */
+        issue_number: parseInt(options.issue, 10),
+        owner: path.owner,
+        repo: path.repo,
+      });
+    }
+
+    return options;
   }
 
   public async createLabel(options: LabelUpdate): Promise<LabelUpdate> {
@@ -181,6 +201,37 @@ export class GithubRemote implements Remote {
     }
   }
 
+  public formatBody(options: CommentUpdate): string {
+    const lines = [];
+    lines.push(`${VERSION_INFO.package.name} v${VERSION_INFO.package.version} has updated the labels on this issue!`);
+    lines.push('');
+
+    for (const change of options.changes) {
+      switch (change.effect) {
+        case ChangeVerb.CONFLICTED:
+          lines.push(`- \`${change.label}\` conflicted with \`${change.cause}\`.`);
+          break;
+        case ChangeVerb.CREATED:
+          lines.push(`- \`${change.label}\` was created by \`${change.cause}\`.`);
+          break;
+        case ChangeVerb.EXISTING:
+          lines.push(`- \`${change.label}\` already existed.`);
+          break;
+        case ChangeVerb.REMOVED:
+          lines.push(`- \`${change.label}\` was removed by \`${change.cause}\`.`);
+          break;
+        case ChangeVerb.REQUIRED:
+          lines.push(`- \`${change.label}\` was removed because it requires \`${change.cause}\`.`);
+          break;
+        default:
+          lines.push(`- an unknown change occurred: \`${JSON.stringify(change)}\`.`);
+          break;
+      }
+    }
+
+    return lines.join('\n');
+  }
+
   protected get writeCapable(): boolean {
     return this.options.dryrun === false;
   }

src/remote/index.ts

@@ -1,4 +1,5 @@
 import { Logger } from 'noicejs';
+import { ChangeRecord, ErrorRecord } from '../resolve';
 
 export interface ProjectQuery {
   project: string;
@@ -12,8 +13,13 @@ export interface IssueQuery extends ProjectQuery {
   issue: string;
 }
 
+/**
+ * Changes to be recorded in a project comment. This takes an abstract set of change/error
+ * records and allows the remote implementation to handle formatting and localization.
+ */
 export interface CommentUpdate extends IssueQuery {
-  comment: string;
+  changes: Array<ChangeRecord>;
+  errors: Array<ErrorRecord>;
 }
 
 export interface IssueUpdate extends IssueQuery {

src/sync.ts

@@ -48,13 +48,18 @@ export async function syncIssueLabels(options: SyncOptions): Promise<unknown> {
     options.logger.debug({ changes, errors, issue, labels }, 'resolved labels');
 
     // TODO: prompt user to update this particular issue
-    const sameLabels = !compareItems(issue.labels, labels) || changes.length > 0;
-    if (sameLabels && errors.length === 0) {
+    const sameLabels = compareItems(issue.labels, labels) || changes.length === 0;
+    if (sameLabels === false && errors.length === 0) {
       options.logger.info({ issue, labels }, 'updating issue');
       await options.remote.updateIssue({
         ...issue,
         labels,
       });
+      await options.remote.createComment({
+        ...issue,
+        changes,
+        errors,
+      });
     }
   }