AI spam

CHANGES.rst

@@ -20,6 +20,8 @@ Unreleased
     tabs in option help text are now escaped, keeping the original completion
     format while still supporting multi-line help. :issue:`3502`
     :issue:`3043` :pr:`3504` :pr:`3508`
+-   Shell completion no longer evaluates parameter defaults or callbacks while
+    parsing completed arguments. :issue:`2614`
 -   Deprecated commands and options with empty or missing help text no longer
     render a stray leading space before the ``(DEPRECATED)`` label. :pr:`3509`
 -   A :class:`Group` with ``invoke_without_command=True`` marks its subcommand as

src/click/core.py

@@ -2386,7 +2386,7 @@ def consume_value(
                 value = envvar_value
                 source = ParameterSource.ENVIRONMENT
 
-        if value is UNSET:
+        if value is UNSET and not ctx.resilient_parsing:
             default_map_value = ctx.lookup_default(self.name)
             if default_map_value is not None or ctx._default_map_has(self.name):
                 value = default_map_value
@@ -2397,7 +2397,7 @@ def consume_value(
                 if isinstance(value, str) and self.nargs != 1:
                     value = self.type.split_envvar_value(value)
 
-        if value is UNSET:
+        if value is UNSET and not ctx.resilient_parsing:
             default_value = self.get_default(ctx)
             if default_value is not UNSET:
                 value = default_value
@@ -2506,7 +2506,7 @@ def process_value(self, ctx: Context, value: t.Any) -> t.Any:
         if self.required and self.value_is_missing(value):
             raise MissingParameter(ctx=ctx, param=self)
 
-        if self.callback is not None:
+        if self.callback is not None and not ctx.resilient_parsing:
             # Legacy case: UNSET is not exposed directly to the callback, but converted
             # to None.
             if value is UNSET:
@@ -3449,7 +3449,7 @@ def process_value(self, ctx: Context, value: t.Any) -> t.Any:
         if self.is_flag and not self.required and self.is_bool_flag and value is UNSET:
             value = False
 
-            if self.callback is not None:
+            if self.callback is not None and not ctx.resilient_parsing:
                 value = self.callback(ctx, self, value)
 
             return value

tests/test_shell_completion.py

@@ -142,6 +142,51 @@ def test_argument_default():
     assert _get_words(cli, ["x"], "b") == ["b"]
 
 
+def test_completion_skips_defaults_and_callbacks():
+    calls = []
+
+    def default():
+        calls.append("default")
+        return "value"
+
+    def callback(ctx, param, value):
+        calls.append(f"callback:{value}")
+        return value
+
+    cli = Command(
+        "cli",
+        params=[
+            Option(["--name"], default=default, callback=callback),
+            Argument(["arg"], type=Choice(["a"])),
+        ],
+    )
+
+    assert _get_words(cli, [], "") == ["a"]
+    assert calls == []
+
+    assert _get_words(cli, ["--name", "value"], "") == ["a"]
+    assert calls == []
+
+
+def test_completion_skips_flag_callback_for_missing_value():
+    calls = []
+
+    def callback(ctx, param, value):
+        calls.append(value)
+        return value
+
+    cli = Command(
+        "cli",
+        params=[
+            Option(["--flag"], is_flag=True, callback=callback),
+            Argument(["arg"], type=Choice(["a"])),
+        ],
+    )
+
+    assert _get_words(cli, [], "") == ["a"]
+    assert calls == []
+
+
 def test_type_choice():
     cli = Command("cli", params=[Option(["-c"], type=Choice(["a1", "a2", "b"]))])
     assert _get_words(cli, ["-c"], "") == ["a1", "a2", "b"]