From 250b60b7fe06a339f02d54b3682e5b982726bf0f Mon Sep 17 00:00:00 2001
From: John Chilton <jmchilton@gmail.com>
Date: Thu, 8 Aug 2024 14:56:32 -0400
Subject: [PATCH] Clarify behavior around unspecified hidden parameters.

---
 lib/galaxy/tool_util/parameters/factory.py      | 2 ++
 lib/galaxy/tool_util/parameters/models.py       | 3 ++-
 test/unit/tool_util/parameter_specification.yml | 2 ++
 3 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/lib/galaxy/tool_util/parameters/factory.py b/lib/galaxy/tool_util/parameters/factory.py
index e21eb4794631..ea735e7e7026 100644
--- a/lib/galaxy/tool_util/parameters/factory.py
+++ b/lib/galaxy/tool_util/parameters/factory.py
@@ -108,9 +108,11 @@ def _from_input_source_galaxy(input_source: InputSource) -> ToolParameterT:
             )
         elif param_type == "hidden":
             optional = input_source.parse_optional()
+            value = input_source.get("value")
             return HiddenParameterModel(
                 name=input_source.parse_name(),
                 optional=optional,
+                value=value,
             )
         elif param_type == "color":
             optional = input_source.parse_optional()
diff --git a/lib/galaxy/tool_util/parameters/models.py b/lib/galaxy/tool_util/parameters/models.py
index 2571ff5c59f5..0deffb02ea71 100644
--- a/lib/galaxy/tool_util/parameters/models.py
+++ b/lib/galaxy/tool_util/parameters/models.py
@@ -346,6 +346,7 @@ def request_requires_value(self) -> bool:
 
 class HiddenParameterModel(BaseGalaxyToolParameterModelDefinition):
     parameter_type: Literal["gx_hidden"] = "gx_hidden"
+    value: Optional[str]
 
     @property
     def py_type(self) -> Type:
@@ -356,7 +357,7 @@ def pydantic_template(self, state_representation: StateRepresentationT) -> Dynam
 
     @property
     def request_requires_value(self) -> bool:
-        return not self.optional
+        return not self.optional and self.value is None
 
 
 def ensure_color_valid(value: Optional[Any]):
diff --git a/test/unit/tool_util/parameter_specification.yml b/test/unit/tool_util/parameter_specification.yml
index 699d49ec29c7..79cfeb9d1572 100644
--- a/test/unit/tool_util/parameter_specification.yml
+++ b/test/unit/tool_util/parameter_specification.yml
@@ -202,6 +202,8 @@ gx_hidden:
     - parameter: moocow
     - parameter: 'some spaces'
     - parameter: ''
+    # it will use a default if value is set in definition and no value supplied (see hidden_param.xml)
+    - {}
   request_invalid:
     - parameter: null
     - parameter: 5