Merge branch 'topic/1260' into 'master'

gnat_xref: add support for deferred constants

Closes #1260

See merge request eng/libadalang/libadalang!1527

ada/ast.py

@@ -1650,6 +1650,12 @@ def gnat_xref():
                 lambda p: p.is_a(T.GenericDecl)
             ).cast(T.GenericDecl).decl.defining_name,
 
+            # Deferred constants case
+            bd._.is_a(T.ObjectDecl)
+            & Not(bd.cast(T.ObjectDecl).has_constant.is_null)
+            & bd.is_in_private_part,
+            Entity.cast(T.Name).enclosing_defining_name.previous_part,
+
             bd.then(lambda bd: bd.is_a(T.DiscriminantSpec)),
             bd.semantic_parent.cast(T.BasicDecl).defining_name,
 

testsuite/tests/name_resolution/gnat_xref_deferred_constants/prj.gpr

@@ -0,0 +1,4 @@
+project Prj is
+  for Source_Dirs use (".");
+  for Main use ("test.adb");
+end Prj;

testsuite/tests/name_resolution/gnat_xref_deferred_constants/test.adb

@@ -0,0 +1,9 @@
+procedure Test is
+   package P is
+      U, V : constant Integer;
+   private
+      U, V : constant Integer := 1;
+   end P;
+begin
+   null;
+end Test;

testsuite/tests/name_resolution/gnat_xref_deferred_constants/test.out

@@ -0,0 +1,15 @@
+== test.adb ==
+test.adb:1:11 => test.adb:1:11 (LAL: ok)
+test.adb:5:7 => test.adb:3:7 (LAL: ok)
+test.adb:5:10 => test.adb:3:10 (LAL: ok)
+test.adb:6:8 => test.adb:2:12 (LAL: ok)
+test.adb:9:5 => test.adb:1:11 (LAL: ok)
+
+Stats:
+GNAT xrefs have 5 entries
+LAL xrefs have:
+  * 5 OK entries (100.00%)
+  * 0 DIFFERENT entries (0.00%)
+  * 0 ERROR entries (0.00%)
+  * 0 MISSING entries (0.00%)
+  * 0 ADDITIONAL entries (0.00%)

testsuite/tests/name_resolution/gnat_xref_deferred_constants/test.yaml

@@ -0,0 +1,2 @@
+driver: gnat-compare
+project_file: prj.gpr