bug-fix: comment link and path mismatch

src/github/github-context.ts

@@ -1,5 +1,6 @@
 import {PullRequest} from '../_namespaces/github'
 import {context} from '@actions/github'
+import {info} from "@actions/core";
 
 const prEvents = ['pull_request', 'pull_request_review', 'pull_request_review_comment']
 
@@ -32,10 +33,10 @@ export function getPullRequestNumber(): number | undefined {
 }
 
 export function relativizePath(path: string): string {
-  let length = process.env.GITHUB_WORKSPACE?.length
-  if (!length) {
-    length = 'undefined'.length
-  }
-
-  return path.substring(length + 1)
+  // owner/repo-name
+  let repo = process.env.GITHUB_REPOSITORY ?? "undefined"
+  let repo_owner = process.env.GITHUB_REPOSITORY_OWNER ?? "undefined"
+  let repo_name = repo.substring(repo_owner.length + 1)
+  // path is in the format of ../workspace/{repo-name}/{RELATIVE_PATH}
+  return path.substring(path.lastIndexOf(repo_name) + repo_name.length + 1)
 }

src/main.ts

@@ -128,7 +128,7 @@ async function run(): Promise<void> {
 }
 
 function isInDiff(issue: IssueOccurrence, diffMap: DiffMap): boolean {
-  const diffHunks = diffMap.get(issue.mainEventFilePathname)
+  const diffHunks = diffMap.get(relativizePath(issue.mainEventFilePathname))
 
   if (!diffHunks) {
     return false

src/reporting.ts

@@ -1,5 +1,6 @@
 import {relativizePath} from './github/github-context'
 import {IssueOccurrence} from './json-v7-schema'
+import {info} from "@actions/core";
 
 export const PRESENT = 'PRESENT'
 export const NOT_PRESENT = 'NOT_PRESENT'
@@ -54,26 +55,38 @@ export function createIssueCommentMessage(issue: IssueOccurrence): string {
   const message = createReviewCommentMessage(issue)
   const relativePath = relativizePath(issue.mainEventFilePathname)
 
+
   return `${message}
 ## Issue location
 This issue was discovered outside the diff for this Pull Request. You can find it at:
 [${relativePath}:${issue.mainEventLineNumber}](${process.env.GITHUB_SERVER_URL}/${process.env.GITHUB_REPOSITORY}/blob/${process.env.GITHUB_SHA}/${relativePath}#L${issue.mainEventLineNumber})
 `
 }
 
+// naive Z-Table, can be optimized to terminate early
+function zTable(input: string) {
+    let table = new Array<number>(input.length).fill(0)
+    for (let i = 1; i < input.length; i++) {
+        for (let j = 0; j < input.length - i; j ++) {
+            if (input.charAt(j) != input.charAt(i + j)) continue
+            table[i]++
+        }
+    }
+    return table
+}
+
 export function getDiffMap(rawDiff: string): DiffMap {
   console.info('Gathering diffs...')
   const diffMap = new Map()
 
   let path = UNKNOWN_FILE
   for (const line of rawDiff.split('\n')) {
     if (line.startsWith('diff --git')) {
-      // TODO: Handle spaces in path
-      path = `${process.env.GITHUB_WORKSPACE}/${line.split(' ')[2].substring(2)}`
-      if (path === undefined) {
-        path = UNKNOWN_FILE
-      }
-
+      // this should give `diff --git a/path b/path`
+      // to get the file itself, we can use longest string match on `path b/path`
+      // since we definitely know paths are equal, path must be the longest string
+      path = line.substring("diff --git a/".length)
+      path = path.substring(0, Math.max(...zTable(path)))
       diffMap.set(path, [])
     }