` telescope -r` should always display the input address #1240 (#1779)

* Added input address to telescope reverse output with skipped records

* Added test to telescope reverse that checks input address

* Fixed linters

* Update tests/gdb-tests/tests/test_command_telescope.py

Co-authored-by: Disconnect3d <dominik.b.czarnota@gmail.com>

* Fixed tests

---------

Co-authored-by: Disconnect3d <dominik.b.czarnota@gmail.com>

pwndbg/commands/telescope.py

@@ -81,6 +81,7 @@ def telescope(address=None, count=telescope_lines, to_string=False, reverse=Fals
         telescope.offset = 0
 
     address = int(address if address else pwndbg.gdblib.regs.sp) & pwndbg.gdblib.arch.ptrmask
+    input_address = address
     count = max(int(count), 1) & pwndbg.gdblib.arch.ptrmask
     delimiter = T.delimiter(offset_delimiter)
     separator = T.separator(offset_separator)
@@ -179,7 +180,7 @@ def telescope(address=None, count=telescope_lines, to_string=False, reverse=Fals
         # Buffer repeating values.
         if skip_repeating_values:
             value = pwndbg.gdblib.memory.pvoid(addr)
-            if last == value:
+            if last == value and addr != input_address:
                 collapse_buffer.append(line)
                 continue
             collapse_repeating_values()

tests/gdb-tests/tests/test_command_telescope.py

@@ -82,3 +82,21 @@ def test_telescope_command_with_address_as_count_and_reversed_flag(start_binary)
     rsp = pwndbg.gdblib.regs.rsp
 
     assert out == ["00:0000│     %#x ◂— 0x0" % (rsp - 8), "01:0008│ rsp %#x ◂— 0x1" % rsp]
+
+
+def test_command_telescope_reverse_skipped_records_shows_input_address(start_binary):
+    """
+    Tests reversed telescope with skipped records shows input address
+    """
+    start_binary(TELESCOPE_BINARY)
+
+    gdb.execute("break break_here")
+    gdb.execute("run")
+    gdb.execute("up")
+    pwndbg.gdblib.memory.write(pwndbg.gdblib.regs.rsp - 8 * 3, b"\x00" * 8 * 4)
+
+    expected_value = hex(pwndbg.gdblib.regs.rsp)
+    result_str = gdb.execute("telescope -r $rsp", to_string=True)
+    result_lines = result_str.strip("\n").split("\n")
+
+    assert expected_value in result_lines[-1]