Fixed duplicate handling.

Improved to call the GitHub API only once with all the comments.
Fixed issue when the filename was matching with pattern.

src/main.ts

@@ -7,6 +7,31 @@ enum DiffScope {
   REMOVED = 'removed'
 }
 
+interface GithubComment {
+  body: string
+  path: string
+  line: number
+  side: string
+}
+
+const hiddenCommentMarkup =
+  '<!-- This is an auto-generated comment: regex-match-commenter-action -->'
+
+function isDuplicateComment(
+  existingComments: GithubComment[],
+  path: string,
+  line: number,
+  side: 'LEFT' | 'RIGHT'
+): boolean {
+  return existingComments.some(
+    comment =>
+      comment.body.includes(hiddenCommentMarkup) &&
+      comment.path === path &&
+      comment.line === line &&
+      comment.side === side
+  )
+}
+
 /**
  * The main function for the action.
  * @returns {Promise<void>} Resolves when the action is complete.
@@ -30,7 +55,7 @@ export async function run(): Promise<void> {
     const octokit = github.getOctokit(token)
     const { context } = github
 
-    core.debug('Fetching pull request ...')
+    core.info('Fetching pull request ...')
     if (context.payload.pull_request == null) {
       core.setFailed('No pull request found.')
       return
@@ -41,7 +66,7 @@ export async function run(): Promise<void> {
     const repo = context.repo.repo
 
     // Fetch PR diff
-    core.debug('Fetching pull request diff ...')
+    core.info('Fetching pull request diff ...')
     const { data: diffData } = await octokit.rest.pulls.get({
       owner,
       repo,
@@ -52,24 +77,37 @@ export async function run(): Promise<void> {
     })
 
     // Fetch existing comments on the PR
-    core.debug('Fetching existing comments ...')
-    const existingComments = await octokit.rest.issues.listComments({
+    core.info('Fetching existing comments ...')
+    const existingComments = await octokit.rest.pulls.listReviewComments({
       owner,
       repo,
-      issue_number: pullRequestNumber
+      pull_number: pullRequestNumber
     })
+    core.debug(JSON.stringify(existingComments, null, 2))
 
     // Parse diff and search for regex matches
-    core.debug('Parsing diff and searching for matches ...')
+    core.info('Parsing diff and searching for matches ...')
     const lines = (diffData as unknown as string).split('\n')
+    core.debug(JSON.stringify(lines, null, 2))
+
+    const regex = new RegExp(regexPattern)
+    const newComments = []
     let foundMatches = false
     let currentFile = ''
     let oldLineNumber = 0
     let newLineNumber = 0
 
     for (const line of lines) {
-      if (line.startsWith('+++ b/')) {
-        currentFile = line.substring('+++ b/'.length)
+      if (line.startsWith('diff --git a/')) {
+        currentFile = line.substring(
+          'diff --git a/'.length,
+          line.indexOf(' b/')
+        )
+        continue
+      }
+
+      if (line.startsWith('--- a/') || line.startsWith('+++ b/')) {
+        // Ignore the file path lines
         continue
       }
 
@@ -98,36 +136,47 @@ export async function run(): Promise<void> {
         ((diffScope === DiffScope.BOTH || diffScope === DiffScope.REMOVED) &&
           line.startsWith('-'))
       ) {
-        const regex = new RegExp(regexPattern)
         if (regex.test(line)) {
-          // Before posting a new comment, check if it already exists
-          const isDuplicate = existingComments.data.some(
-            comment => comment.body === matchFoundMessage
+          const side = line.startsWith('+') ? 'RIGHT' : 'LEFT'
+          const isDuplicate = isDuplicateComment(
+            existingComments.data as GithubComment[],
+            currentFile,
+            side === 'RIGHT' ? newLineNumber : oldLineNumber,
+            side
+          )
+          foundMatches = true
+
+          core.debug(`Regex matched ...`)
+          core.debug(
+            JSON.stringify(
+              {
+                currentFile,
+                lineContent: line,
+                lineNumber: side === 'RIGHT' ? newLineNumber : oldLineNumber,
+                isDuplicate
+              },
+              null,
+              2
+            )
           )
 
           if (!isDuplicate) {
-            core.debug(`Match found`)
-            foundMatches = true
-            const side = line.startsWith('+') ? 'RIGHT' : 'LEFT'
-
-            await octokit.rest.pulls.createReviewComment({
-              owner,
-              repo,
-              pull_number: pullRequestNumber,
-              body: matchFoundMessage,
-              commit_id: context.payload.pull_request.head.sha,
+            core.info(`Match found`)
+            newComments.push({
               path: currentFile,
-              side,
-              line: side === 'LEFT' ? oldLineNumber : newLineNumber
+              body: `${hiddenCommentMarkup}\n${matchFoundMessage}`,
+              line: side === 'RIGHT' ? newLineNumber : oldLineNumber,
+              side
             })
           } else {
-            core.debug(`Match found but already commented`)
+            core.info(`Match found but already commented`)
           }
         }
       }
     }
 
     if (!foundMatches) {
+      core.info('Adding comment about no matches found ...')
       await octokit.rest.issues.createComment({
         owner,
         repo,
@@ -136,16 +185,19 @@ export async function run(): Promise<void> {
       })
     }
 
-    // Optional: Mark PR as changes requested
-    if (markChangesRequested && foundMatches) {
+    if (newComments.length > 0) {
+      core.info('Adding comments to the pull request ...')
       await octokit.rest.pulls.createReview({
         owner,
         repo,
         pull_number: pullRequestNumber,
-        event: 'REQUEST_CHANGES',
-        body: changesRequestedMessage
+        event: markChangesRequested ? 'REQUEST_CHANGES' : undefined,
+        body: changesRequestedMessage,
+        comments: newComments
       })
     }
+
+    // If there are no matches and no new comments, then we don't need to update the PR
   } catch (error) {
     // Fail the workflow run if an error occurs
     if (error instanceof Error) core.setFailed(error.message)