Support empy4 together with empy3 (#753)

Signed-off-by: Jose Luis Rivero <jrivero@honurobotics.com>

Author: j-rivero

.github/workflows/ci.yaml

@@ -12,6 +12,22 @@ jobs:
     uses: ros-infrastructure/ci/.github/workflows/pytest.yaml@main
     with:
       matrix-filter: del(.matrix.os[] | select(contains("windows")))
+
+  # Dedicated job for testing with empy < 4
+  pytest-empy-legacy:
+    runs-on: ubuntu-latest
+    name: Test empy < 4 compatibility
+    steps:
+      - uses: actions/checkout@v4
+      - name: Set up Python
+        uses: actions/setup-python@v4
+      - name: Install dependencies with empy < 4
+        run: |
+          python -m pip install --upgrade pip
+          pip install -e .[test] 'empy<4'
+      - name: Run tests
+        run: |
+          python -m pytest test/ -v
   yamllint:
     runs-on: ubuntu-latest
     steps:

bloom/generators/debian/generator.py

@@ -78,6 +78,8 @@
 from bloom.logging import is_debug
 from bloom.logging import warning
 
+from bloom.util import expand_template_em
+
 from bloom.commands.git.patch.common import get_patch_config
 from bloom.commands.git.patch.common import set_patch_config
 
@@ -534,7 +536,7 @@ def __process_template_folder(path, subs):
         info("Expanding '{0}' -> '{1}'".format(
             os.path.relpath(item),
             os.path.relpath(template_path)))
-        result = em.expand(template, **subs)
+        result = expand_template_em(template, subs)
         # Don't write an empty file
         if len(result) == 0 and \
            os.path.basename(template_path) in ['copyright']:

bloom/generators/rpm/generator.py

@@ -81,6 +81,7 @@
 
 from bloom.util import code
 from bloom.util import execute_command
+from bloom.util import expand_template_em
 from bloom.util import maybe_continue
 
 try:
@@ -89,12 +90,6 @@
     debug(traceback.format_exc())
     error("rosdistro was not detected, please install it.", exit=True)
 
-try:
-    import em
-except ImportError:
-    debug(traceback.format_exc())
-    error("empy was not detected, please install it.", exit=True)
-
 # Drop the first log prefix for this command
 enable_drop_first_log_prefix(True)
 
@@ -379,7 +374,7 @@ def __process_template_folder(path, subs):
         info("Expanding '{0}' -> '{1}'".format(
             os.path.relpath(item),
             os.path.relpath(template_path)))
-        result = em.expand(template, **subs)
+        result = expand_template_em(template, subs)
         # Write the result
         with io.open(template_path, 'w', encoding='utf-8') as f:
             if sys.version_info.major == 2:

bloom/util.py

@@ -84,6 +84,23 @@
     to_unicode = str
 
 
+def expand_template_em(template, subs):
+    """
+    Compatibility function for EmPy 3 and 4.
+    EmPy 3: em.expand(template, **kwargs)
+    EmPy 4: em.expand(template, locals=dict)
+    """
+    try:
+        import em
+    except ImportError:
+        error("empy was not detected, please install it.", exit=True)
+
+    if em.__version__.startswith('3'):
+        return em.expand(template, **subs)
+    else:
+        return em.expand(template, locals=subs)
+
+
 def flush_stdin():
     try:
         from termios import tcflush, TCIFLUSH

setup.py

@@ -1,6 +1,5 @@
 #!/usr/bin/env python
 
-import sys
 from setuptools import find_packages, setup
 
 
@@ -20,7 +19,7 @@
     install_requires=[
         'catkin_pkg >= 0.4.3',
         'setuptools < 82',
-        'empy < 4',
+        'empy',
         'packaging',
         'python-dateutil',
         'PyYAML',

test/unit_tests/test_generators/test_debian/test_generator.py

@@ -2,9 +2,9 @@
 
 from ....utils.common import redirected_stdio
 
-from bloom.generators.debian.generator import em
 from bloom.generators.debian.generator import get_changelogs
 from bloom.generators.debian.generator import format_description
+from bloom.util import expand_template_em
 
 from catkin_pkg.packages import find_packages
 
@@ -24,7 +24,7 @@ def test_unicode_templating():
         assert 'bad_changelog_pkg' in packages
         chlogs = get_changelogs(packages['bad_changelog_pkg'])
         template = "@(changelog)"
-        em.expand(template, {'changelog': chlogs[0][2]})
+        expand_template_em(template, {'changelog': chlogs[0][2]})
 
 
 def test_format_description():