Fix BTreeSet and BTreeMap gdb pretty-printers

src/etc/debugger_pretty_printers_common.py

@@ -375,32 +375,6 @@ def extract_tail_head_ptr_and_cap_from_std_vecdeque(vec_val):
     assert data_ptr.type.get_dwarf_type_kind() == DWARF_TYPE_CODE_PTR
     return (tail, head, data_ptr, capacity)
 
-
-def extract_length_and_ptr_from_std_btreeset(vec_val):
-    assert vec_val.type.get_type_kind() == TYPE_KIND_STD_BTREESET
-    map = vec_val.get_child_at_index(0)
-    root = map.get_child_at_index(0)
-    length = map.get_child_at_index(1).as_integer()
-    node = root.get_child_at_index(0)
-    ptr = node.get_child_at_index(0)
-    unique_ptr_val = ptr.get_child_at_index(0)
-    data_ptr = unique_ptr_val.get_child_at_index(0)
-    assert data_ptr.type.get_dwarf_type_kind() == DWARF_TYPE_CODE_PTR
-    return (length, data_ptr)
-
-
-def extract_length_and_ptr_from_std_btreemap(vec_val):
-    assert vec_val.type.get_type_kind() == TYPE_KIND_STD_BTREEMAP
-    root = vec_val.get_child_at_index(0)
-    length = vec_val.get_child_at_index(1).as_integer()
-    node = root.get_child_at_index(0)
-    ptr = node.get_child_at_index(0)
-    unique_ptr_val = ptr.get_child_at_index(0)
-    data_ptr = unique_ptr_val.get_child_at_index(0)
-    assert data_ptr.type.get_dwarf_type_kind() == DWARF_TYPE_CODE_PTR
-    return (length, data_ptr)
-
-
 def extract_length_and_ptr_from_slice(slice_val):
     assert (slice_val.type.get_type_kind() == TYPE_KIND_SLICE or
             slice_val.type.get_type_kind() == TYPE_KIND_STR_SLICE)

src/etc/gdb_rust_pretty_printing.py

@@ -304,6 +304,32 @@ def children(self):
             yield (str(index), (gdb_ptr + index).dereference())
 
 
+# Yield each key (and optionally value) from a BoxedNode.
+def children_of_node(boxed_node, height, want_values):
+    ptr = boxed_node['ptr']['pointer']
+    # This is written oddly because we don't want to rely on the field name being `__0`.
+    node_ptr = ptr[ptr.type.fields()[0]]
+    if height > 0:
+        type_name = str(node_ptr.type.target()).replace('LeafNode', 'InternalNode')
+        node_type = gdb.lookup_type(type_name)
+        node_ptr = node_ptr.cast(node_type.pointer())
+        leaf = node_ptr['data']
+    else:
+        leaf = node_ptr.dereference()
+    keys = leaf['keys']['value']['value']
+    if want_values:
+        values = leaf['vals']['value']['value']
+    length = int(leaf['len'])
+    for i in xrange(0, length + 1):
+        if height > 0:
+            for child in children_of_node(node_ptr['edges'][i], height - 1, want_values):
+                yield child
+        if i < length:
+            if want_values:
+                yield (keys[i], values[i])
+            else:
+                yield keys[i]
+
 class RustStdBTreeSetPrinter(object):
     def __init__(self, val):
         self.__val = val
@@ -313,21 +339,16 @@ def display_hint():
         return "array"
 
     def to_string(self):
-        (length, data_ptr) = \
-            rustpp.extract_length_and_ptr_from_std_btreeset(self.__val)
         return (self.__val.type.get_unqualified_type_name() +
-                ("(len: %i)" % length))
+                ("(len: %i)" % self.__val.get_wrapped_value()['map']['length']))
 
     def children(self):
-        (length, data_ptr) = \
-            rustpp.extract_length_and_ptr_from_std_btreeset(self.__val)
-        leaf_node = GdbValue(data_ptr.get_wrapped_value().dereference())
-        maybe_uninit_keys = leaf_node.get_child_at_index(3)
-        manually_drop_keys = maybe_uninit_keys.get_child_at_index(1)
-        keys = manually_drop_keys.get_child_at_index(0)
-        gdb_ptr = keys.get_wrapped_value()
-        for index in xrange(length):
-            yield (str(index), gdb_ptr[index])
+        root = self.__val.get_wrapped_value()['map']['root']
+        node_ptr = root['node']
+        i = 0
+        for child in children_of_node(node_ptr, root['height'], False):
+            yield (str(i), child)
+            i = i + 1
 
 
 class RustStdBTreeMapPrinter(object):
@@ -339,26 +360,17 @@ def display_hint():
         return "map"
 
     def to_string(self):
-        (length, data_ptr) = \
-            rustpp.extract_length_and_ptr_from_std_btreemap(self.__val)
         return (self.__val.type.get_unqualified_type_name() +
-                ("(len: %i)" % length))
+                ("(len: %i)" % self.__val.get_wrapped_value()['length']))
 
     def children(self):
-        (length, data_ptr) = \
-            rustpp.extract_length_and_ptr_from_std_btreemap(self.__val)
-        leaf_node = GdbValue(data_ptr.get_wrapped_value().dereference())
-        maybe_uninit_keys = leaf_node.get_child_at_index(3)
-        manually_drop_keys = maybe_uninit_keys.get_child_at_index(1)
-        keys = manually_drop_keys.get_child_at_index(0)
-        keys_ptr = keys.get_wrapped_value()
-        maybe_uninit_vals = leaf_node.get_child_at_index(4)
-        manually_drop_vals = maybe_uninit_vals.get_child_at_index(1)
-        vals = manually_drop_vals.get_child_at_index(0)
-        vals_ptr = vals.get_wrapped_value()
-        for index in xrange(length):
-            yield (str(index), keys_ptr[index])
-            yield (str(index), vals_ptr[index])
+        root = self.__val.get_wrapped_value()['root']
+        node_ptr = root['node']
+        i = 0
+        for child in children_of_node(node_ptr, root['height'], True):
+            yield (str(i), child[0])
+            yield (str(i), child[1])
+            i = i + 1
 
 
 class RustStdStringPrinter(object):

src/test/debuginfo/pretty-std-collections.rs

@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+// ignore-tidy-linelength
 // ignore-windows failing on win32 bot
 // ignore-freebsd: gdb package too new
 // ignore-android: FIXME(#10381)
@@ -20,10 +21,10 @@
 // gdb-command: run
 
 // gdb-command: print btree_set
-// gdb-check:$1 = BTreeSet<i32>(len: 3) = {3, 5, 7}
+// gdb-check:$1 = BTreeSet<i32>(len: 15) = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14}
 
 // gdb-command: print btree_map
-// gdb-check:$2 = BTreeMap<i32, i32>(len: 3) = {[3] = 3, [5] = 7, [7] = 4}
+// gdb-check:$2 = BTreeMap<i32, i32>(len: 15) = {[0] = 0, [1] = 1, [2] = 2, [3] = 3, [4] = 4, [5] = 5, [6] = 6, [7] = 7, [8] = 8, [9] = 9, [10] = 10, [11] = 11, [12] = 12, [13] = 13, [14] = 14}
 
 // gdb-command: print vec_deque
 // gdb-check:$3 = VecDeque<i32>(len: 3, cap: 8) = {5, 3, 7}
@@ -38,15 +39,15 @@ fn main() {
 
     // BTreeSet
     let mut btree_set = BTreeSet::new();
-    btree_set.insert(5);
-    btree_set.insert(3);
-    btree_set.insert(7);
+    for i in 0..15 {
+        btree_set.insert(i);
+    }
 
     // BTreeMap
     let mut btree_map = BTreeMap::new();
-    btree_map.insert(5, 7);
-    btree_map.insert(3, 3);
-    btree_map.insert(7, 4);
+    for i in 0..15 {
+        btree_map.insert(i, i);
+    }
 
     // VecDeque
     let mut vec_deque = VecDeque::new();