[JENKINS-38406] GIT_BRANCH wrongly set.

I have a jenkins job that runs when code is pushed to `master` and `develop` branch. This job also picks up PRs. This job also has `sha1` as a build parameter to trigger builds manually.

The job picks up PRs and builds them. Same with pushes to `master` or `develop`. The issue is when The job is triggered manually. It seems to pickup a random branch. sometimes a PR, sometimes `origin/develop`. The GIT_BRANCH environment variable is overwritten with some other branch and not sha1.

*Job config*

````

build parameters: sha1 (default value: origin/) so technically, the job should fail as there is no branch called `origin/`

Branches to build -1 : origin/master

Branches to build - 2: origin/develop

Branches to build - 3: ${sha1}

Refspec: +refs/heads/*:refs/remotes/origin/* +refs/pull/*:refs/remotes/origin/pr/*

• [√ ] Build when a change is pushed to GitHub


• [√ ] GitHub Pull Request Builder
  
  ````

*Jenkins and plugin versions*

````

jenkins version: 2.7.1

Git client plugin: 2.0.0

Git plugin: 3.0.0

GitHub API Plugin: 1.77

GitHub plugin: 1.21.1

GitHub Pull Request Builder: 1.33.1

````

---
Originally reported by puneeth_n, imported from: GIT_BRANCH wrongly set.

• status: Open
  
• priority: Major
  
• component(s): git-plugin
  
• label(s): scm-api-tidy-scrub
  
• resolution: Unresolved
  
• votes: 6
  
• watchers: 8
  
• imported: 2025-12-02
  

Raw content of original issue

I have a jenkins job that runs when code is pushed to `master` and `develop` branch. This job also picks up PRs. This job also has `sha1` as a build parameter to trigger builds manually.


The job picks up PRs and builds them. Same with pushes to `master` or `develop`. The issue is when The job is triggered manually. It seems to pickup a random branch. sometimes a PR, sometimes `origin/develop`. The GIT_BRANCH environment variable is overwritten with some other branch and not sha1.


*Job config*

````

build parameters: sha1 (default value: origin/<branchName>) so technically, the job should fail as there is no branch called `origin/<branchName>`

Branches to build -1 : origin/master

Branches to build - 2: origin/develop

Branches to build - 3: ${sha1}

Refspec: +refs/heads/*:refs/remotes/origin/* +refs/pull/*:refs/remotes/origin/pr/*




	
[√ ]  Build when a change is pushed to GitHub

	
[√ ]  GitHub Pull Request Builder

````



*Jenkins and plugin versions*

````

jenkins version: 2.7.1


Git client plugin: 2.0.0	

Git plugin: 3.0.0

GitHub API Plugin: 1.77	

GitHub plugin: 1.21.1

GitHub Pull Request Builder: 1.33.1

````