Fix and changelog closes #793

invoke/completion/complete.py

@@ -12,16 +12,13 @@
 from ..util import debug, task_name_sort_key
 
 
-def complete(names, core, initial_context, collection):
+def complete(names, core, initial_context, collection, parser):
     # Strip out program name (scripts give us full command line)
     # TODO: this may not handle path/to/script though?
     invocation = re.sub(r"^({}) ".format("|".join(names)), "", core.remainder)
     debug("Completing for invocation: {!r}".format(invocation))
     # Tokenize (shlex will have to do)
     tokens = shlex.split(invocation)
-    # Make ourselves a parser (can't just reuse original one as it's mutated /
-    # been overwritten)
-    parser = Parser(initial=initial_context, contexts=collection.to_contexts())
     # Handle flags (partial or otherwise)
     if tokens and tokens[-1].startswith("-"):
         tail = tokens[-1]

invoke/program.py

@@ -523,6 +523,9 @@ def parse_cleanup(self):
                 core=self.core,
                 initial_context=self.initial_context,
                 collection=self.collection,
+                # NOTE: can't reuse self.parser as it has likely been mutated
+                # between when it was set and now.
+                parser=self._make_parser(),
             )
 
         # Fallback behavior if no tasks were given & no default specified
@@ -717,6 +720,16 @@ def _update_core_context(self, context, new_args):
             if arg.got_value:
                 context.args[key]._value = arg._value
 
+
+    def _make_parser(self):
+        return Parser(
+            initial=self.initial_context,
+            contexts=self.collection.to_contexts(
+                ignore_unknown_help=self.config.tasks.ignore_unknown_help
+            ),
+        )
+
+
     def parse_tasks(self):
         """
         Parse leftover args, which are typically tasks & per-task args.
@@ -731,12 +744,7 @@ def parse_tasks(self):
 
         .. versionadded:: 1.0
         """
-        self.parser = Parser(
-            initial=self.initial_context,
-            contexts=self.collection.to_contexts(
-                ignore_unknown_help=self.config.tasks.ignore_unknown_help
-            ),
-        )
+        self.parser = self._make_parser()
         debug("Parsing tasks against {!r}".format(self.collection))
         result = self.parser.parse_argv(self.core.unparsed)
         self.core_via_tasks = result.pop(0)

sites/www/changelog.rst

@@ -2,6 +2,9 @@
 Changelog
 =========
 
+- :bug:`793` Refactor CLI parser instantiation such that the
+  ``tasks.ignore_unknown_help`` feature (added in 1.7) works when Invoke is run
+  in ``--complete`` mode, i.e. in tab-completion scripts.
 - :bug:`-` Fix errors thrown when comparing `~invoke.tasks.Task` objects to
   non-Task objects; such comparisons are now always false.
 - :release:`1.7.1 <2022-05-11>`