cmds.projects.lib.templates.tmpl_render(): search_path

Add an additional keyword-argument search_path to templates.tmpl_render(). It allows to specifiy a list of directory paths in which a template of a given name can be found. It defaults to [], in which case only the built-in templates are considered. Otherwise file locations are tried first, then the built-in templates.
Signed-off-by: Jan Lindemann <jan@janware.com>

src/python/jw/pkg/cmds/projects/lib/templates.py

@@ -1,6 +1,8 @@
 import textwrap
 
-def format_lines(template, values, li_quote, li_delimiter):
+def format_lines(
+    template: str, values: dict[str, str], li_quote: bool, li_delimiter: str
+) -> str:
 
     def __format_value(val):
         if not li_quote:
@@ -63,11 +65,31 @@ _templates = {
 }
 
 def tmpl_render(
-    template_name: str, values, li_quote = False, li_delimiter = '\n'
+    template_name: str,
+    values,
+    li_quote = False,
+    li_delimiter = '\n',
+    search_path: list[str] = []
 ) -> str:
+
+    def __format(template: str) -> str:
         return format_lines(
-        textwrap.dedent(_templates[template_name]),
+            template,
             values,
             li_quote = li_quote,
             li_delimiter = li_delimiter,
         )
+
+    for d in search_path:
+        path = d + '/' + template_name
+        try:
+            with open(path, 'r') as f:
+                template = f.read()
+                return __format(template)
+        except FileNotFoundError:
+            pass
+
+    raw = _templates.get(template_name, None)
+    if raw is None:
+        raise Exception(f'Failed to find template "{template_name}"')
+    return __format(textwrap.dedent(raw))