1 files changed, 80 insertions, 0 deletions
diff --git a/debian/lib/python/debian_linux/utils.py b/debian/lib/python/debian_linux/utils.py
new file mode 100644
index 000000000..8f0463413
--- /dev/null
+++ b/debian/lib/python/debian_linux/utils.py
@@ -0,0 +1,80 @@
+import io
+import os
+import re
+import textwrap
+import typing
+
+import jinja2
+
+from .debian import SourcePackage, BinaryPackage, TestsControl
+
+
+class Templates(object):
+    dirs: list[str]
+    _cache: dict[str, str]
+    _jinja2: jinja2.Environment
+
+    def __init__(self, dirs: list[str] = ["debian/templates"]) -> None:
+        self.dirs = dirs
+
+        self._cache = {}
+        self._jinja2 = jinja2.Environment(
+            # autoescape uses HTML safe escaping, which does not help us
+            autoescape=False,
+            keep_trailing_newline=True,
+            trim_blocks=True,
+            undefined=jinja2.StrictUndefined,
+        )
+
+    def _read(self, name: str) -> typing.Any:
+        pkgid, name = name.rsplit('.', 1)
+
+        for suffix in ['.j2', '.in', '']:
+            for dir in self.dirs:
+                filename = "%s/%s.%s%s" % (dir, pkgid, name, suffix)
+                if os.path.exists(filename):
+                    with open(filename, 'r', encoding='utf-8') as f:
+                        mode = os.stat(f.fileno()).st_mode
+                        return (f.read(), mode, suffix)
+
+        raise KeyError(name)
+
+    def _get(self, key: str) -> typing.Any:
+        try:
+            return self._cache[key]
+        except KeyError:
+            self._cache[key] = value = self._read(key)
+            return value
+
+    def get(self, key: str, context: dict[str, str] = {}) -> str:
+        value = self._get(key)
+        suffix = value[2]
+
+        if context:
+            if suffix == '.in':
+                def subst(match):
+                    return context[match.group(1)]
+                return re.sub(r'@([-_a-z0-9]+)@', subst, str(value[0]))
+
+            elif suffix == '.j2':
+                return self._jinja2.from_string(value[0]).render(context)
+
+        return value[0]
+
+    def get_mode(self, key: str) -> str:
+        return self._get(key)[1]
+
+    def get_control(self, key: str, context: dict[str, str] = {}) -> BinaryPackage:
+        return BinaryPackage.read_rfc822(io.StringIO(self.get(key, context)))
+
+    def get_source_control(self, key: str, context: dict[str, str] = {}) -> SourcePackage:
+        return SourcePackage.read_rfc822(io.StringIO(self.get(key, context)))
+
+    def get_tests_control(self, key: str, context: dict[str, str] = {}) -> TestsControl:
+        return TestsControl.read_rfc822(io.StringIO(self.get(key, context)))
+
+
+class TextWrapper(textwrap.TextWrapper):
+    wordsep_re = re.compile(
+        r'(\s+|'                                  # any whitespace
+        r'(?<=[\w\!\"\'\&\.\,\?])-{2,}(?=\w))')   # em-dash