Skip to content

[lldb-dap] Add readOnly attribute for variables #151884

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Oct 15, 2025
Merged

[lldb-dap] Add readOnly attribute for variables #151884

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
35 changes: 26 additions & 9 deletions lldb/test/API/tools/lldb-dap/variables/TestDAP_variables.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -65,6 +65,11 @@ def verify_values(self, verify_dict, actual, varref_dict=None, expression=None):
self.assertNotIn(
key, actual, 'key "%s" is not expected in %s' % (key, actual)
)
isReadOnly = verify_dict.get("readOnly", False)
attributes = actual.get("presentationHint", {}).get("attributes", [])
self.assertEqual(
isReadOnly, "readOnly" in attributes, "%s %s" % (verify_dict, actual)
)
hasVariablesReference = "variablesReference" in actual
varRef = None
if hasVariablesReference:
Expand Down Expand Up @@ -179,8 +184,9 @@ def do_test_scopes_variables_setVariable_evaluate(
"children": {
"x": {"equals": {"type": "int", "value": "11"}},
"y": {"equals": {"type": "int", "value": "22"}},
"buffer": {"children": buffer_children},
"buffer": {"children": buffer_children, "readOnly": True},
},
"readOnly": True,
},
"x": {"equals": {"type": "int"}},
}
Expand Down Expand Up @@ -456,8 +462,10 @@ def do_test_scopes_and_evaluate_expansion(self, enableAutoVariableSummaries: boo
"buffer": {
"children": buffer_children,
"equals": {"indexedVariables": 16},
"readOnly": True,
},
},
"readOnly": True,
},
"x": {
"equals": {"type": "int"},
Expand Down Expand Up @@ -540,7 +548,7 @@ def do_test_scopes_and_evaluate_expansion(self, enableAutoVariableSummaries: boo
"children": {
"x": {"equals": {"type": "int", "value": "11"}},
"y": {"equals": {"type": "int", "value": "22"}},
"buffer": {"children": buffer_children},
"buffer": {"children": buffer_children, "readOnly": True},
},
}

Expand Down Expand Up @@ -634,11 +642,17 @@ def do_test_indexedVariables(self, enableSyntheticChildDebugging: bool):
# "[raw]" child.
raw_child_count = 1 if enableSyntheticChildDebugging else 0
verify_locals = {
"small_array": {"equals": {"indexedVariables": 5}},
"large_array": {"equals": {"indexedVariables": 200}},
"small_vector": {"equals": {"indexedVariables": 5 + raw_child_count}},
"large_vector": {"equals": {"indexedVariables": 200 + raw_child_count}},
"pt": {"missing": ["indexedVariables"]},
"small_array": {"equals": {"indexedVariables": 5}, "readOnly": True},
"large_array": {"equals": {"indexedVariables": 200}, "readOnly": True},
"small_vector": {
"equals": {"indexedVariables": 5 + raw_child_count},
"readOnly": True,
},
"large_vector": {
"equals": {"indexedVariables": 200 + raw_child_count},
"readOnly": True,
},
"pt": {"missing": ["indexedVariables"], "readOnly": True},
}
self.verify_variables(verify_locals, locals)

Expand All @@ -652,7 +666,10 @@ def do_test_indexedVariables(self, enableSyntheticChildDebugging: bool):
"[4]": {"equals": {"type": "int", "value": "0"}},
}
if enableSyntheticChildDebugging:
verify_children["[raw]"] = ({"contains": {"type": ["vector"]}},)
verify_children["[raw]"] = {
"contains": {"type": ["vector"]},
"readOnly": True,
}

children = self.dap_server.request_variables(locals[2]["variablesReference"])[
"body"
Expand All @@ -672,7 +689,7 @@ def test_return_variables(self):
return_name: {"equals": {"type": "int", "value": "300"}},
"argc": {},
"argv": {},
"pt": {},
"pt": {"readOnly": True},
"x": {},
"return_result": {"equals": {"type": "int"}},
}
Expand Down
8 changes: 8 additions & 0 deletions lldb/tools/lldb-dap/ProtocolUtils.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -301,6 +301,14 @@ Variable CreateVariable(lldb::SBValue v, int64_t var_ref, bool format_hex,
if (lldb::addr_t addr = v.GetLoadAddress(); addr != LLDB_INVALID_ADDRESS)
var.memoryReference = addr;

bool is_readonly = v.GetType().IsAggregateType() ||
Copy link
Member

@walter-erquinigo walter-erquinigo Aug 5, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

This is not the right place for this check. Instead, add a method in the SBType class that does it. A possible name is IsWritable, and invoke it from here.

Copy link
Collaborator

@labath labath Aug 6, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

If we're going to be implementing this in the SB API, then I don't think SBType is the right place for it. It should probably be a property of SBValue, as one can easily imagine situations where a value is not modifiable, even though another value of the same type is.

Copy link
Contributor Author

@DrSergei DrSergei Aug 6, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I agree with you, for example, a const global integer variable and a const local integer variable. I don't want to add anything to the SB API because there are a lot of corner cases (and also it looks like SetData has less preconditions than SetValueFromCString, so we need two different versions of IsWritable for both functions). I added simple heuristics at the lldb-dap level to avoid confusing users in most cases. CodeLLDB uses different heuristics for that. I think the better solution is to place the check here.

Copy link
Member

@walter-erquinigo walter-erquinigo Aug 6, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

yeah, i'm fine with this

v.GetValueType() == lldb::eValueTypeRegisterSet;
if (is_readonly) {
if (!var.presentationHint)
var.presentationHint = {VariablePresentationHint()};
var.presentationHint->attributes.push_back("readOnly");
}

return var;
}

Expand Down
Loading