chore: raise exception if user is on default branch + tries to create the PR (#455)

# Motivation

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# Content

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# Testing

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# Please check the following before marking your PR as ready for review

- [ ] I have added tests for my changes
- [ ] I have updated the documentation or added new documentation as
needed

Author: christinewangcw

src/codegen/sdk/core/codebase.py

@@ -902,6 +902,9 @@ def create_pr(self, title: str, body: str) -> PullRequest:
         if self._op.git_cli.head.is_detached:
             msg = "Cannot make a PR from a detached HEAD"
             raise ValueError(msg)
+        if self._op.git_cli.active_branch.name == self._op.default_branch:
+            msg = "Cannot make a PR from the default branch"
+            raise ValueError(msg)
         self._op.stage_and_commit_all_changes(message=title)
         self._op.push_changes()
         return self._op.remote_git_repo.create_pull(head_branch_name=self._op.git_cli.active_branch.name, base_branch_name=self._op.default_branch, title=title, body=body)

tests/integration/codegen/git/codebase/test_codebase_create_pr.py

@@ -8,7 +8,8 @@
 def test_codebase_create_pr_active_branch(codebase: Codebase):
     head = f"test-create-pr-{uuid.uuid4()}"
     codebase.checkout(branch=head, create_if_missing=True)
-    codebase.files[0].remove()
+    file = codebase.files[0]
+    file.remove()
     codebase.commit()
     pr = codebase.create_pr(title="test-create-pr title", body="test-create-pr body")
     assert pr.title == "test-create-pr title"
@@ -17,10 +18,21 @@ def test_codebase_create_pr_active_branch(codebase: Codebase):
     assert pr.state == "open"
     assert pr.head.ref == head
     assert pr.base.ref == "main"
+    assert pr.get_files().totalCount == 1
+    assert pr.get_files()[0].filename == file.file_path
 
 
 def test_codebase_create_pr_detached_head(codebase: Codebase):
     codebase.checkout(commit=codebase._op.git_cli.head.commit)  # move to detached head state
     with pytest.raises(ValueError) as exc_info:
         codebase.create_pr(title="test-create-pr title", body="test-create-pr body")
     assert "Cannot make a PR from a detached HEAD" in str(exc_info.value)
+
+
+def test_codebase_create_pr_active_branch_is_default_branch(codebase: Codebase):
+    codebase.checkout(branch=codebase._op.default_branch)
+    codebase.files[0].remove()
+    codebase.commit()
+    with pytest.raises(ValueError) as exc_info:
+        codebase.create_pr(title="test-create-pr title", body="test-create-pr body")
+    assert "Cannot make a PR from the default branch" in str(exc_info.value)