Implement DAP setVariable request

This patch implements the DAP setVariable request.

setVariable is a bit odd in that it specifies the variable to modify
by passing in the variable's container and the name of the variable.
This approach can't handle variable shadowing (there are a couple of
open DAP bugs on this topic), so this patch renames duplicates to
avoid the problem.

1 files changed, 54 insertions, 0 deletions

diff --git a/gdb/testsuite/gdb.dap/assign.py b/gdb/testsuite/gdb.dap/assign.py
new file mode 100644
index 0000000..d7b4868
--- /dev/null
+++ b/gdb/testsuite/gdb.dap/assign.py
@@ -0,0 +1,54 @@
+# Copyright (C) 2022-2023 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+import gdb
+
+
+class EmptyPrinter(gdb.ValuePrinter):
+    """Pretty print a structure"""
+
+    def __init__(self, val):
+        self._val = val
+
+    def to_string(self):
+        return "empty"
+
+
+class FullPrinter(gdb.ValuePrinter):
+    """Pretty print a structure"""
+
+    def __init__(self, val):
+        self._val = val
+
+    def to_string(self):
+        return "full"
+
+    def children(self):
+        # This is used to test the renaming code.
+        yield "datum", self._val["datum"]
+        yield "datum", self._val["datum"]
+
+
+def lookup_function(val):
+    if val.type.tag == "special_type":
+        if val["disc"] == 0:
+            return EmptyPrinter(val)
+        else:
+            return FullPrinter(val)
+    return None
+
+
+gdb.pretty_printers.append(lookup_function)