--new-pr can't be empty

easybuild/tools/github.py

@@ -618,6 +618,8 @@ def _easyconfigs_pr_common(paths, start_branch=None, pr_branch=None, target_acco
         print_msg(git_repo.git.diff(cached=True) + '\n', log=_log, prefix=False)
 
     diff_stat = git_repo.git.diff(cached=True, stat=True)
+    if not diff_stat:
+        raise EasyBuildError("No changed files found. Refused to make empty pull request.")
 
     # commit
     if commit_msg:

test/framework/options.py

@@ -47,8 +47,8 @@
 from easybuild.tools.config import DEFAULT_MODULECLASSES
 from easybuild.tools.config import find_last_log, get_build_log_path, get_module_syntax, module_classes
 from easybuild.tools.environment import modify_env
-from easybuild.tools.filetools import mkdir, read_file, write_file
-from easybuild.tools.github import fetch_github_token
+from easybuild.tools.filetools import download_file, mkdir, read_file, write_file
+from easybuild.tools.github import GITHUB_RAW, GITHUB_EB_MAIN, GITHUB_EASYCONFIGS_REPO, URL_SEPARATOR, fetch_github_token
 from easybuild.tools.options import EasyBuildOptions, parse_external_modules_metadata, set_tmpdir
 from easybuild.tools.toolchain.utilities import TC_CONST_PREFIX
 from easybuild.tools.run import run_cmd
@@ -2350,6 +2350,34 @@ def test_new_update_pr(self):
             regex = re.compile(regex, re.M)
             self.assertTrue(regex.search(txt), "Pattern '%s' found in: %s" % (regex.pattern, txt))
 
+    def test_empty_pr(self):
+        """Test use of --new-pr (dry run only) with no changes"""
+        if self.github_token is None:
+            print "Skipping test_new_pr, no GitHub token available?"
+            return
+
+        # get file from develop branch
+        test_ecs_dir = os.path.join(os.path.dirname(os.path.abspath(__file__)), 'easyconfigs')
+        full_url = URL_SEPARATOR.join([GITHUB_RAW, GITHUB_EB_MAIN, GITHUB_EASYCONFIGS_REPO, 'develop/easybuild/easyconfigs/z/zlib/zlib-1.2.8.eb'])
+        ec = download_file('zlib-1.2.8.eb', full_url, path=os.path.join(test_ecs_dir, 'zlib-1.2.8.eb'), forced=True)
+
+        # try to open new pr with unchanged file
+        os.environ['EASYBUILD_GITHUB_USER'] = GITHUB_TEST_ACCOUNT
+        args = [
+            '--new-pr',
+            '--experimental',
+            ec,
+            '-D',
+        ]
+
+        self.mock_stdout(True)
+        error_msg = 'No changed files found. Refused to make empty pull request.'
+        self.assertErrorRegex(EasyBuildError, error_msg, self.eb_main, args, do_build=True, raise_error=True)
+        self.mock_stdout(False)
+
+        os.remove(os.path.join(test_ecs_dir, 'zlib-1.2.8.eb'))
+
+
     def test_show_config(self):
         """"Test --show-config and --show-full-config."""