App.distro_info(): Add method

Add a method distro_info() to App, essentially providing CmdInfo's macro-expansion of platform information to other interested code.
Signed-off-by: Jan Lindemann <jan@janware.com>

src/python/jw/pkg/App.py

@@ -418,6 +418,23 @@ class App(Base):
             self.__distro = ret
         return self.__distro
 
+    def distro_info(self, fmt: str) -> str:
+        ret = fmt
+        for macro in re.findall("%{([A-Za-z_-]+)}", fmt):
+            try:
+                name = 'distro_' + macro.replace('-', '_')
+                if name == 'distro_info':
+                    continue
+                val = getattr(self, name)
+                patt = r'%{' + macro + r'}'
+                if ret.find(patt) == -1:
+                    continue
+                ret = ret.replace(patt, val)
+            except Exception as e:
+                log(ERR, f'Failed to expand macro "{macro}" inside "{fmt}": {str(e)}')
+                raise
+        return ret
+
     def find_dir(self, name: str, search_subdirs: list[str]=[], search_absdirs: list[str]=[], pretty: bool=True):
         return self.__find_dir(name, search_subdirs, search_absdirs, pretty)