fix: determine if the branch exists first

src/services/db/GitFileSystemService.ts

@@ -203,6 +203,34 @@ export default class GitFileSystemService {
       })
   }
 
+  // Determine if the given branch is present in the local repo copy
+  isLocalBranchPresent(
+    repoName: string,
+    branchName: string
+  ): ResultAsync<boolean, GitFileSystemError> {
+    const efsVolPath = this.getEfsVolPathFromBranch(branchName)
+    return ResultAsync.fromPromise(
+      this.git
+        .cwd({ path: `${efsVolPath}/${repoName}`, root: false })
+        .branchLocal(),
+      (error) => {
+        logger.error(
+          `Unable to get the list of local branches in ${efsVolPath}/${repoName}: ${JSON.stringify(
+            error
+          )}`
+        )
+
+        if (error instanceof GitError) {
+          return new GitFileSystemError(
+            "Unable to get the list of local branches"
+          )
+        }
+
+        return new GitFileSystemError("An unknown error occurred")
+      }
+    ).map((result) => result.all.includes(branchName))
+  }
+
   // Ensure that the repository is in the specified branch
   ensureCorrectBranch(
     repoName: string,
@@ -318,7 +346,7 @@ export default class GitFileSystemService {
         .log([branchName]),
       (error) => {
         logger.error(
-          `Error when getting latest commit of "${branchName}" branch: ${error}, when trying to access ${efsVolPath}/${repoName} for ${branchName}`
+          `Error when getting Git log of "${branchName}" branch: ${error}, when trying to access ${efsVolPath}/${repoName} for ${branchName}`
         )
 
         if (error instanceof GitError) {
@@ -1610,8 +1638,14 @@ export default class GitFileSystemService {
     repoName: string,
     branchName: string
   ): ResultAsync<GitHubCommitData, GitFileSystemError> {
-    return this.getGitLog(repoName, branchName)
-      .orElse(() => this.getGitLog(repoName, `origin/${branchName}`))
+    return this.isLocalBranchPresent(repoName, branchName)
+      .andThen((isBranchLocallyPresent) => {
+        if (isBranchLocallyPresent) {
+          return this.getGitLog(repoName, branchName)
+        }
+
+        return this.getGitLog(repoName, `origin/${branchName}`)
+      })
       .andThen((logSummary) => {
         const possibleCommit = logSummary.latest
         if (this.isDefaultLogFields(possibleCommit)) {