Fix T68971: Copy As New Driver from Material node creates a bad reference.

NodeTree structures of materials and some other data blocks are
effectively node group datablock objects that are contained inside
the parent block. Thus, direct references to them are only valid
while blender is running, and are lost on save.

Fix Copy As New Driver to create a reference that goes through
the owner datablock, by adding a new ID flag to mark private
pseudo-datablocks.

Also fix functions that return full paths to structures and
properties, e.g. used in python tooltips. Functions for paths
from ID to struct or property can't be changed because of
Animation Data related code.

Reviewers: mont29

Differential Revision: https://developer.blender.org/D5559

1 files changed, 98 insertions, 15 deletions

diff --git a/source/blender/makesrna/intern/rna_access.c b/source/blender/makesrna/intern/rna_access.c
index 8327456f460..bc015a378cc 100644
--- a/source/blender/makesrna/intern/rna_access.c
+++ b/source/blender/makesrna/intern/rna_access.c
@@ -47,6 +47,7 @@
 #include "BKE_fcurve.h"
 #include "BKE_main.h"
 #include "BKE_report.h"
+#include "BKE_node.h"
 
 #include "DEG_depsgraph.h"
 
@@ -5757,6 +5758,61 @@ static char *rna_path_from_ID_to_idpgroup(PointerRNA *ptr)
   }
 }
 
+/**
+ * Find the actual ID pointer and path from it to the given ID.
+ *
+ * \param id: ID reference to search the global owner for.
+ * \param[out] r_path: Path from the real ID to the initial ID.
+ * \return The ID pointer, or NULL in case of failure.
+ */
+ID *RNA_find_real_ID_and_path(Main *bmain, ID *id, const char **r_path)
+{
+  if (r_path) {
+    *r_path = "";
+  }
+
+  if ((id != NULL) && (id->flag & LIB_PRIVATE_DATA)) {
+    switch (GS(id->name)) {
+      case ID_NT:
+        if (r_path) {
+          *r_path = "node_tree";
+        }
+        return BKE_node_tree_find_owner_ID(bmain, (bNodeTree *)id);
+
+      default:
+        return NULL;
+    }
+  }
+  else {
+    return id;
+  }
+}
+
+static char *rna_prepend_real_ID_path(Main *bmain, ID *id, char *path, ID **r_real)
+{
+  if (path) {
+    const char *prefix;
+    char *new_path = NULL;
+
+    *r_real = RNA_find_real_ID_and_path(bmain, id, &prefix);
+
+    if (*r_real) {
+      if (prefix[0]) {
+        new_path = BLI_sprintfN("%s%s%s", prefix, path[0] == '[' ? "" : ".", path);
+      }
+      else {
+        return path;
+      }
+    }
+
+    MEM_freeN(path);
+    return new_path;
+  }
+  else {
+    return NULL;
+  }
+}
+
 char *RNA_path_from_ID_to_struct(PointerRNA *ptr)
 {
   char *ptrpath = NULL;
@@ -5799,6 +5855,13 @@ char *RNA_path_from_ID_to_struct(PointerRNA *ptr)
   return ptrpath;
 }
 
+char *RNA_path_from_real_ID_to_struct(Main *bmain, PointerRNA *ptr, struct ID **r_real)
+{
+  char *path = RNA_path_from_ID_to_struct(ptr);
+
+  return rna_prepend_real_ID_path(bmain, ptr->owner_id, path, r_real);
+}
+
 static void rna_path_array_multi_from_flat_index(const int dimsize[RNA_MAX_ARRAY_LENGTH],
                                                  const int totdims,
                                                  const int index_dim,
@@ -5905,6 +5968,14 @@ char *RNA_path_from_ID_to_property(PointerRNA *ptr, PropertyRNA *prop)
   return RNA_path_from_ID_to_property_index(ptr, prop, 0, -1);
 }
 
+char *RNA_path_from_real_ID_to_property_index(
+    Main *bmain, PointerRNA *ptr, PropertyRNA *prop, int index_dim, int index, ID **r_real)
+{
+  char *path = RNA_path_from_ID_to_property_index(ptr, prop, index_dim, index);
+
+  return rna_prepend_real_ID_path(bmain, ptr->owner_id, path, r_real);
+}
+
 /**
  * \return the path to given ptr/prop from the closest ancestor of given type,
  * if any (else return NULL).
@@ -5951,20 +6022,34 @@ char *RNA_path_resolve_from_type_to_property(PointerRNA *ptr,
  * Get the ID as a python representation, eg:
  *   bpy.data.foo["bar"]
  */
-char *RNA_path_full_ID_py(ID *id)
+char *RNA_path_full_ID_py(Main *bmain, ID *id)
 {
+  const char *path;
+  ID *id_real = RNA_find_real_ID_and_path(bmain, id, &path);
+
+  if (id_real) {
+    id = id_real;
+  }
+  else {
+    path = "";
+  }
+
   char id_esc[(sizeof(id->name) - 2) * 2];
 
   BLI_strescape(id_esc, id->name + 2, sizeof(id_esc));
 
-  return BLI_sprintfN("bpy.data.%s[\"%s\"]", BKE_idcode_to_name_plural(GS(id->name)), id_esc);
+  return BLI_sprintfN("bpy.data.%s[\"%s\"]%s%s",
+                      BKE_idcode_to_name_plural(GS(id->name)),
+                      id_esc,
+                      path[0] ? "." : "",
+                      path);
 }
 
 /**
  * Get the ID.struct as a python representation, eg:
  *   bpy.data.foo["bar"].some_struct
  */
-char *RNA_path_full_struct_py(struct PointerRNA *ptr)
+char *RNA_path_full_struct_py(Main *bmain, struct PointerRNA *ptr)
 {
   char *id_path;
   char *data_path;
@@ -5976,7 +6061,7 @@ char *RNA_path_full_struct_py(struct PointerRNA *ptr)
   }
 
   /* never fails */
-  id_path = RNA_path_full_ID_py(ptr->owner_id);
+  id_path = RNA_path_full_ID_py(bmain, ptr->owner_id);
 
   data_path = RNA_path_from_ID_to_struct(ptr);
 
@@ -5996,10 +6081,8 @@ char *RNA_path_full_struct_py(struct PointerRNA *ptr)
  * Get the ID.struct.property as a python representation, eg:
  *   bpy.data.foo["bar"].some_struct.some_prop[10]
  */
-char *RNA_path_full_property_py_ex(PointerRNA *ptr,
-                                   PropertyRNA *prop,
-                                   int index,
-                                   bool use_fallback)
+char *RNA_path_full_property_py_ex(
+    Main *bmain, PointerRNA *ptr, PropertyRNA *prop, int index, bool use_fallback)
 {
   char *id_path;
   const char *data_delim;
@@ -6013,7 +6096,7 @@ char *RNA_path_full_property_py_ex(PointerRNA *ptr,
   }
 
   /* never fails */
-  id_path = RNA_path_full_ID_py(ptr->owner_id);
+  id_path = RNA_path_full_ID_py(bmain, ptr->owner_id);
 
   data_path = RNA_path_from_ID_to_property(ptr, prop);
   if (data_path) {
@@ -6046,9 +6129,9 @@ char *RNA_path_full_property_py_ex(PointerRNA *ptr,
   return ret;
 }
 
-char *RNA_path_full_property_py(PointerRNA *ptr, PropertyRNA *prop, int index)
+char *RNA_path_full_property_py(Main *bmain, PointerRNA *ptr, PropertyRNA *prop, int index)
 {
-  return RNA_path_full_property_py_ex(ptr, prop, index, false);
+  return RNA_path_full_property_py_ex(bmain, ptr, prop, index, false);
 }
 
 /**
@@ -6646,16 +6729,16 @@ char *RNA_pointer_as_string_id(bContext *C, PointerRNA *ptr)
   return cstring;
 }
 
-static char *rna_pointer_as_string__bldata(PointerRNA *ptr)
+static char *rna_pointer_as_string__bldata(Main *bmain, PointerRNA *ptr)
 {
   if (ptr->type == NULL || ptr->owner_id == NULL) {
     return BLI_strdup("None");
   }
   else if (RNA_struct_is_ID(ptr->type)) {
-    return RNA_path_full_ID_py(ptr->owner_id);
+    return RNA_path_full_ID_py(bmain, ptr->owner_id);
   }
   else {
-    return RNA_path_full_struct_py(ptr);
+    return RNA_path_full_struct_py(bmain, ptr);
   }
 }
 
@@ -6672,7 +6755,7 @@ char *RNA_pointer_as_string(bContext *C,
     return RNA_pointer_as_string_id(C, ptr_prop);
   }
   else {
-    return rna_pointer_as_string__bldata(ptr_prop);
+    return rna_pointer_as_string__bldata(CTX_data_main(C), ptr_prop);
   }
 }