Merge branch 'topic/1034' into 'master'

Fixed lower bounds for array types and subtypes (gnatX)

Closes #1034

See merge request eng/libadalang/libadalang!1456

ada/ast.py

@@ -9180,11 +9180,15 @@ def index_type(dim=Int):
     @langkit_property()
     def xref_equation():
         return Entity.types.logic_all(
-            lambda typ: typ.subtype_indication.sub_equation
+            lambda typ:
+            typ.subtype_name.xref_no_overloading
+            & If(typ.lower_bound.is_null,
+                 LogicTrue(),
+                 typ.lower_bound.sub_equation)
         )
 
     is_static = Property(Entity.types.all(
-        lambda t: t.subtype_indication.is_static_subtype
+        lambda t: t.subtype_name.is_static_subtype
     ))
 
 
@@ -23219,11 +23223,12 @@ class UnconstrainedArrayIndex(AdaNode):
     List of unconstrained array indexes.
     """
 
-    subtype_indication = Field(type=SubtypeIndication)
+    subtype_name = Field(type=Name)
+    lower_bound = Field(type=Expr)
 
     @langkit_property(dynamic_vars=[origin])
     def designated_type():
-        return Entity.subtype_indication.designated_type
+        return Entity.subtype_name.name_designated_type
 
 
 class AbstractStateDecl(BasicDecl):

ada/grammar.py

@@ -175,7 +175,7 @@ def end_named_block():
     ),
 
     unconstrained_index=UnconstrainedArrayIndex(
-        A.subtype_indication, "range", "<>"
+        A.subtype_name, "range", Opt(A.simple_expr, ".."), "<>"
     ),
 
     array_type_def=ArrayTypeDef(
@@ -1426,7 +1426,11 @@ def end_named_block():
     ),
 
     discrete_range=Or(
-        BinOp(A.simple_expr, Op.alt_double_dot(".."), A.simple_expr),
+        BinOp(
+            A.simple_expr,
+            Op.alt_double_dot(".."),
+            Or(A.simple_expr, A.box_expr)
+        ),
         Predicate(A.name, T.Name.is_range_attribute)
     ),
 

testsuite/tests/name_resolution/fixed_lower_bound/test.adb

@@ -0,0 +1,40 @@
+--  Check that the following experimental GNAT feature:
+--    Fixed lower bounds for array types and subtypes
+--  is correctly supported.
+
+--  https://github.com/AdaCore/ada-spark-rfcs/blob/master/prototyped/rfc-fixed-lower-bound.rst
+pragma Extensions_Allowed (On);
+
+procedure Test is
+   type A is array (Integer range 1 .. <>) of Integer;
+   pragma Test_Block;
+
+   type String_1 is array (Positive range 1 .. <>) of Character;
+   pragma Test_Block;
+
+   subtype Fixed_String is String (1 .. <>);
+   pragma Test_Statement;
+
+   subtype Fixed_String_2 is String (Integer range 1 .. <>);
+   pragma Test_Statement;
+
+   type Int_Matrix_1 is array (Positive range 1 .. <>,
+                               Positive range <>) of Integer;
+   pragma Test_Block;
+   type Int_Matrix_2 is array (Positive range <>,
+                               Positive range 1 .. <>) of Integer;
+   pragma Test_Block;
+   type Int_Matrix_3 is array (Positive range 1 .. <>,
+                               Positive range 1 .. <>) of Integer;
+   pragma Test_Block;
+
+   type Matrix is array (Positive range <>, Positive range <>) of Integer;
+   pragma Test_Block;
+
+   subtype SMatrix is Matrix (2 .. <>, 2 .. <>);
+   pragma Test_Statement;
+   subtype SMatrix2 is Matrix (Integer range 2 .. <>, Integer range 2 .. <>);
+   pragma Test_Statement;
+begin
+   null;
+end Test;

testsuite/tests/name_resolution/fixed_lower_bound/test.out

@@ -0,0 +1,245 @@
+Analyzing test.adb
+##################
+
+Resolving xrefs for node <ArrayTypeDef test.adb:9:14-9:54>
+**********************************************************
+
+Expr: <Id "Integer" test.adb:9:21-9:28>
+  references:    <DefiningName "Integer" __standard:4:8-4:15>
+  type:          None
+  expected type: None
+Expr: <Int test.adb:9:35-9:36>
+  references:    None
+  type:          <ConcreteTypeDecl ["Universal_Int_Type_"] __standard:116:3-116:45>
+  expected type: None
+Expr: <Id "Integer" test.adb:9:47-9:54>
+  references:    <DefiningName "Integer" __standard:4:8-4:15>
+  type:          None
+  expected type: None
+
+Resolving xrefs for node <ArrayTypeDef test.adb:12:21-12:64>
+************************************************************
+
+Expr: <Id "Positive" test.adb:12:28-12:36>
+  references:    <DefiningName "Positive" __standard:6:11-6:19>
+  type:          None
+  expected type: None
+Expr: <Int test.adb:12:43-12:44>
+  references:    None
+  type:          <ConcreteTypeDecl ["Universal_Int_Type_"] __standard:116:3-116:45>
+  expected type: None
+Expr: <Id "Character" test.adb:12:55-12:64>
+  references:    <DefiningName "Character" __standard:21:8-21:17>
+  type:          None
+  expected type: None
+
+Resolving xrefs for node <SubtypeDecl ["Fixed_String"] test.adb:15:4-15:45>
+***************************************************************************
+
+Expr: <Id "String" test.adb:15:28-15:34>
+  references:    <DefiningName "String" __standard:105:8-105:14>
+  type:          None
+  expected type: None
+Expr: <BinOp test.adb:15:36-15:43>
+  type:          <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+  expected type: <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+Expr: <Int test.adb:15:36-15:37>
+  references:    None
+  type:          <ConcreteTypeDecl ["Universal_Int_Type_"] __standard:116:3-116:45>
+  expected type: <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+Expr: <OpDoubleDot ".." test.adb:15:38-15:40>
+  references:    None
+  type:          None
+  expected type: None
+Expr: <BoxExpr test.adb:15:41-15:43>
+  type:          <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+  expected type: <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+
+Resolving xrefs for node <SubtypeDecl ["Fixed_String_2"] test.adb:18:4-18:61>
+*****************************************************************************
+
+Expr: <Id "String" test.adb:18:30-18:36>
+  references:    <DefiningName "String" __standard:105:8-105:14>
+  type:          None
+  expected type: None
+Expr: <Id "Integer" test.adb:18:38-18:45>
+  references:    <DefiningName "Integer" __standard:4:8-4:15>
+  type:          None
+  expected type: None
+Expr: <BinOp test.adb:18:52-18:59>
+  type:          <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+  expected type: <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+Expr: <Int test.adb:18:52-18:53>
+  references:    None
+  type:          <ConcreteTypeDecl ["Universal_Int_Type_"] __standard:116:3-116:45>
+  expected type: <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+Expr: <OpDoubleDot ".." test.adb:18:54-18:56>
+  references:    None
+  type:          None
+  expected type: None
+Expr: <BoxExpr test.adb:18:57-18:59>
+  type:          <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+  expected type: <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+
+Resolving xrefs for node <ArrayTypeDef test.adb:21:25-22:61>
+************************************************************
+
+Expr: <Id "Positive" test.adb:21:32-21:40>
+  references:    <DefiningName "Positive" __standard:6:11-6:19>
+  type:          None
+  expected type: None
+Expr: <Int test.adb:21:47-21:48>
+  references:    None
+  type:          <ConcreteTypeDecl ["Universal_Int_Type_"] __standard:116:3-116:45>
+  expected type: None
+Expr: <Id "Positive" test.adb:22:32-22:40>
+  references:    <DefiningName "Positive" __standard:6:11-6:19>
+  type:          None
+  expected type: None
+Expr: <Id "Integer" test.adb:22:54-22:61>
+  references:    <DefiningName "Integer" __standard:4:8-4:15>
+  type:          None
+  expected type: None
+
+Resolving xrefs for node <ArrayTypeDef test.adb:24:25-25:66>
+************************************************************
+
+Expr: <Id "Positive" test.adb:24:32-24:40>
+  references:    <DefiningName "Positive" __standard:6:11-6:19>
+  type:          None
+  expected type: None
+Expr: <Id "Positive" test.adb:25:32-25:40>
+  references:    <DefiningName "Positive" __standard:6:11-6:19>
+  type:          None
+  expected type: None
+Expr: <Int test.adb:25:47-25:48>
+  references:    None
+  type:          <ConcreteTypeDecl ["Universal_Int_Type_"] __standard:116:3-116:45>
+  expected type: None
+Expr: <Id "Integer" test.adb:25:59-25:66>
+  references:    <DefiningName "Integer" __standard:4:8-4:15>
+  type:          None
+  expected type: None
+
+Resolving xrefs for node <ArrayTypeDef test.adb:27:25-28:66>
+************************************************************
+
+Expr: <Id "Positive" test.adb:27:32-27:40>
+  references:    <DefiningName "Positive" __standard:6:11-6:19>
+  type:          None
+  expected type: None
+Expr: <Int test.adb:27:47-27:48>
+  references:    None
+  type:          <ConcreteTypeDecl ["Universal_Int_Type_"] __standard:116:3-116:45>
+  expected type: None
+Expr: <Id "Positive" test.adb:28:32-28:40>
+  references:    <DefiningName "Positive" __standard:6:11-6:19>
+  type:          None
+  expected type: None
+Expr: <Int test.adb:28:47-28:48>
+  references:    None
+  type:          <ConcreteTypeDecl ["Universal_Int_Type_"] __standard:116:3-116:45>
+  expected type: None
+Expr: <Id "Integer" test.adb:28:59-28:66>
+  references:    <DefiningName "Integer" __standard:4:8-4:15>
+  type:          None
+  expected type: None
+
+Resolving xrefs for node <ArrayTypeDef test.adb:31:19-31:74>
+************************************************************
+
+Expr: <Id "Positive" test.adb:31:26-31:34>
+  references:    <DefiningName "Positive" __standard:6:11-6:19>
+  type:          None
+  expected type: None
+Expr: <Id "Positive" test.adb:31:45-31:53>
+  references:    <DefiningName "Positive" __standard:6:11-6:19>
+  type:          None
+  expected type: None
+Expr: <Id "Integer" test.adb:31:67-31:74>
+  references:    <DefiningName "Integer" __standard:4:8-4:15>
+  type:          None
+  expected type: None
+
+Resolving xrefs for node <SubtypeDecl ["SMatrix"] test.adb:34:4-34:49>
+**********************************************************************
+
+Expr: <Id "Matrix" test.adb:34:23-34:29>
+  references:    <DefiningName "Matrix" test.adb:31:9-31:15>
+  type:          None
+  expected type: None
+Expr: <BinOp test.adb:34:31-34:38>
+  type:          <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+  expected type: <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+Expr: <Int test.adb:34:31-34:32>
+  references:    None
+  type:          <ConcreteTypeDecl ["Universal_Int_Type_"] __standard:116:3-116:45>
+  expected type: <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+Expr: <OpDoubleDot ".." test.adb:34:33-34:35>
+  references:    None
+  type:          None
+  expected type: None
+Expr: <BoxExpr test.adb:34:36-34:38>
+  type:          <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+  expected type: <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+Expr: <BinOp test.adb:34:40-34:47>
+  type:          <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+  expected type: <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+Expr: <Int test.adb:34:40-34:41>
+  references:    None
+  type:          <ConcreteTypeDecl ["Universal_Int_Type_"] __standard:116:3-116:45>
+  expected type: <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+Expr: <OpDoubleDot ".." test.adb:34:42-34:44>
+  references:    None
+  type:          None
+  expected type: None
+Expr: <BoxExpr test.adb:34:45-34:47>
+  type:          <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+  expected type: <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+
+Resolving xrefs for node <SubtypeDecl ["SMatrix2"] test.adb:36:4-36:78>
+***********************************************************************
+
+Expr: <Id "Matrix" test.adb:36:24-36:30>
+  references:    <DefiningName "Matrix" test.adb:31:9-31:15>
+  type:          None
+  expected type: None
+Expr: <Id "Integer" test.adb:36:32-36:39>
+  references:    <DefiningName "Integer" __standard:4:8-4:15>
+  type:          None
+  expected type: None
+Expr: <BinOp test.adb:36:46-36:53>
+  type:          <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+  expected type: <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+Expr: <Int test.adb:36:46-36:47>
+  references:    None
+  type:          <ConcreteTypeDecl ["Universal_Int_Type_"] __standard:116:3-116:45>
+  expected type: <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+Expr: <OpDoubleDot ".." test.adb:36:48-36:50>
+  references:    None
+  type:          None
+  expected type: None
+Expr: <BoxExpr test.adb:36:51-36:53>
+  type:          <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+  expected type: <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+Expr: <Id "Integer" test.adb:36:55-36:62>
+  references:    <DefiningName "Integer" __standard:4:8-4:15>
+  type:          None
+  expected type: None
+Expr: <BinOp test.adb:36:69-36:76>
+  type:          <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+  expected type: <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+Expr: <Int test.adb:36:69-36:70>
+  references:    None
+  type:          <ConcreteTypeDecl ["Universal_Int_Type_"] __standard:116:3-116:45>
+  expected type: <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+Expr: <OpDoubleDot ".." test.adb:36:71-36:73>
+  references:    None
+  type:          None
+  expected type: None
+Expr: <BoxExpr test.adb:36:74-36:76>
+  type:          <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+  expected type: <ConcreteTypeDecl ["Integer"] __standard:4:3-4:54>
+
+
+Done.

testsuite/tests/name_resolution/fixed_lower_bound/test.yaml

@@ -0,0 +1,2 @@
+driver: name-resolution
+input_sources: [test.adb]

testsuite/tests/parser/full_type_decl_16/test.out

@@ -11,13 +11,9 @@ ConcreteTypeDecl[1:1-1:49]
 |  |  |f_types:
 |  |  |  UnconstrainedArrayIndexList[1:20-1:36]
 |  |  |  |  UnconstrainedArrayIndex[1:20-1:36]
-|  |  |  |  |f_subtype_indication:
-|  |  |  |  |  SubtypeIndication[1:20-1:27]
-|  |  |  |  |  |f_has_not_null:
-|  |  |  |  |  |  NotNullAbsent[1:20-1:20]
-|  |  |  |  |  |f_name:
-|  |  |  |  |  |  Id[1:20-1:27]: Integer
-|  |  |  |  |  |f_constraint: <null>
+|  |  |  |  |f_subtype_name:
+|  |  |  |  |  Id[1:20-1:27]: Integer
+|  |  |  |  |f_lower_bound: <null>
 |  |f_component_type:
 |  |  ComponentDef[1:41-1:48]
 |  |  |f_has_aliased:

user_manual/changes/libadalang/1034.yaml

@@ -0,0 +1,6 @@
+type: new-feature
+title: Fixed lower bounds for array types and subtypes
+description: |
+  This change adds support for the GNAT experimental feature allowing fixed
+  lower bounds for array types and subtypes.
+date: 2023-11-07