[ruby/yarp] Introduce a BlockLocalVariableNode

This is a tradeoff that I think is worth it. Right now we have a
location list that tracks the location of each of the block locals.
Instead, I'd like to make that a node list that has a proper node
in each spot in the list. In doing so, we eliminate the need to have
a location list at all, making it simpler on all of the various
consumers as we have one fewer field type. There should be minimal
memory implications here since this syntax is exceedingly rare.

ruby/prism@04d329ddf0

test/yarp/location_test.rb

@@ -67,6 +67,12 @@ def test_BlockArgumentNode
       assert_location(BlockArgumentNode, "foo(&bar)", 4...8) { |node| node.arguments.arguments.last }
     end
 
+    def test_BlockLocalVariableNode
+      assert_location(BlockLocalVariableNode, "foo { |;bar| }", 8...11) do |node|
+        node.block.parameters.locals.first
+      end
+    end
+
     def test_BlockNode
       assert_location(BlockNode, "foo {}", 4...6, &:block)
       assert_location(BlockNode, "foo do end", 4...10, &:block)

test/yarp/snapshots/procs.txt

@@ -16,7 +16,9 @@ ProgramNode(0...266)(
            nil,
            nil
          ),
-         [(7...8), (10...11), (13...14)],
+         [BlockLocalVariableNode(7...8)(:b),
+          BlockLocalVariableNode(10...11)(:c),
+          BlockLocalVariableNode(13...14)(:d)],
          (3...4),
          (14...15)
        ),

test/yarp/snapshots/seattlerb/block_arg_scope.txt

@@ -20,7 +20,7 @@ ProgramNode(0...12)(
              nil,
              nil
            ),
-           [(8...9)],
+           [BlockLocalVariableNode(8...9)(:c)],
            (4...5),
            (9...10)
          ),

test/yarp/snapshots/seattlerb/block_arg_scope2.txt

@@ -20,7 +20,8 @@ ProgramNode(0...14)(
              nil,
              nil
            ),
-           [(7...8), (10...11)],
+           [BlockLocalVariableNode(7...8)(:c),
+            BlockLocalVariableNode(10...11)(:d)],
            (3...4),
            (11...12)
          ),

test/yarp/snapshots/seattlerb/block_scope.txt

@@ -10,7 +10,12 @@ ProgramNode(0...10)(
        nil,
        BlockNode(2...10)(
          [:b],
-         BlockParametersNode(4...8)(nil, [(6...7)], (4...5), (7...8)),
+         BlockParametersNode(4...8)(
+           nil,
+           [BlockLocalVariableNode(6...7)(:b)],
+           (4...5),
+           (7...8)
+         ),
          nil,
          (2...3),
          (9...10)

test/yarp/snapshots/seattlerb/pipe_semicolon.txt

@@ -10,7 +10,12 @@ ProgramNode(0...18)(
        nil,
        BlockNode(4...18)(
          [:c],
-         BlockParametersNode(7...14)(nil, [(11...12)], (7...8), (13...14)),
+         BlockParametersNode(7...14)(
+           nil,
+           [BlockLocalVariableNode(11...12)(:c)],
+           (7...8),
+           (13...14)
+         ),
          nil,
          (4...6),
          (15...18)

test/yarp/snapshots/seattlerb/stabby_proc_scope.txt

@@ -16,7 +16,7 @@ ProgramNode(0...11)(
            nil,
            nil
          ),
-         [(6...7)],
+         [BlockLocalVariableNode(6...7)(:b)],
          (2...3),
          (7...8)
        ),

test/yarp/snapshots/unparser/corpus/literal/block.txt

@@ -91,7 +91,7 @@ ProgramNode(0...737)(
              nil,
              nil
            ),
-           [(44...45)],
+           [BlockLocalVariableNode(44...45)(:x)],
            (39...40),
            (45...46)
          ),
@@ -326,7 +326,7 @@ ProgramNode(0...737)(
              nil,
              nil
            ),
-           [(181...182)],
+           [BlockLocalVariableNode(181...182)(:b)],
            (176...177),
            (182...183)
          ),
@@ -366,7 +366,7 @@ ProgramNode(0...737)(
              nil,
              nil
            ),
-           [(200...201)],
+           [BlockLocalVariableNode(200...201)(:b)],
            (196...197),
            (201...202)
          ),
@@ -398,7 +398,8 @@ ProgramNode(0...737)(
          [:a, :b],
          BlockParametersNode(215...223)(
            nil,
-           [(218...219), (221...222)],
+           [BlockLocalVariableNode(218...219)(:a),
+            BlockLocalVariableNode(221...222)(:b)],
            (215...216),
            (222...223)
          ),

test/yarp/snapshots/unparser/corpus/literal/lambda.txt

@@ -110,7 +110,7 @@ ProgramNode(0...80)(
            nil,
            nil
          ),
-         [(74...75)],
+         [BlockLocalVariableNode(74...75)(:c)],
          (67...68),
          (75...76)
        ),

test/yarp/snapshots/whitequark/arg_scope.txt

@@ -10,7 +10,12 @@ ProgramNode(0...13)(
        nil,
        BlockNode(6...13)(
          [:a],
-         BlockParametersNode(7...11)(nil, [(9...10)], (7...8), (10...11)),
+         BlockParametersNode(7...11)(
+           nil,
+           [BlockLocalVariableNode(9...10)(:a)],
+           (7...8),
+           (10...11)
+         ),
          StatementsNode(11...12)([LocalVariableReadNode(11...12)(:a, 0)]),
          (6...7),
          (12...13)

test/yarp/snapshots/whitequark/blockargs.txt

@@ -250,7 +250,7 @@ ProgramNode(0...550)(
          [:a],
          BlockParametersNode(117...123)(
            nil,
-           [(120...121)],
+           [BlockLocalVariableNode(120...121)(:a)],
            (117...118),
            (122...123)
          ),
@@ -272,7 +272,7 @@ ProgramNode(0...550)(
          [:a],
          BlockParametersNode(130...134)(
            nil,
-           [(132...133)],
+           [BlockLocalVariableNode(132...133)(:a)],
            (130...131),
            (133...134)
          ),

test/yarp/snapshots/whitequark/send_lambda_args_shadow.txt

@@ -16,7 +16,8 @@ ProgramNode(0...19)(
            nil,
            nil
          ),
-         [(6...9), (11...14)],
+         [BlockLocalVariableNode(6...9)(:foo),
+          BlockLocalVariableNode(11...14)(:bar)],
          (2...3),
          (14...15)
        ),

yarp/config.yml

@@ -520,6 +520,15 @@ nodes:
 
           bar(&args)
           ^^^^^^^^^^
+  - name: BlockLocalVariableNode
+    fields:
+      - name: name
+        type: constant
+    comment: |
+      Represents a block local variable.
+
+          a { |; b| }
+                 ^
   - name: BlockNode
     fields:
       - name: locals
@@ -556,7 +565,7 @@ nodes:
         type: node?
         kind: ParametersNode
       - name: locals
-        type: location[]
+        type: node[]
       - name: opening_loc
         type: location?
       - name: closing_loc

yarp/node.h

@@ -4,9 +4,6 @@
 #include "yarp/defines.h"
 #include "yarp/parser.h"
 
-// Append a token to the given list.
-void yp_location_list_append(yp_location_list_t *list, const yp_token_t *token);
-
 // Append a new node onto the end of the node list.
 void yp_node_list_append(yp_node_list_t *list, yp_node_t *node);
 
@@ -31,7 +28,6 @@ YP_EXPORTED_FUNCTION void yp_node_memsize(yp_node_t *node, yp_memsize_t *memsize
 YP_EXPORTED_FUNCTION const char * yp_node_type_to_str(yp_node_type_t node_type);
 
 #define YP_EMPTY_NODE_LIST ((yp_node_list_t) { .nodes = NULL, .size = 0, .capacity = 0 })
-#define YP_EMPTY_LOCATION_LIST ((yp_location_list_t) { .locations = NULL, .size = 0, .capacity = 0 })
 
 #endif // YARP_NODE_H
 

yarp/templates/ext/yarp/api_node.c.erb

@@ -152,12 +152,6 @@ yp_ast_new(yp_parser_t *parser, yp_node_t *node, rb_encoding *encoding) {
                     }
                     <%- when YARP::StringField -%>
                     argv[<%= index %>] = yp_string_new(&cast-><%= field.name %>, encoding);
-                    <%- when YARP::LocationListField -%>
-                    argv[<%= index %>] = rb_ary_new_capa(cast-><%= field.name %>.size);
-                    for (size_t index = 0; index < cast-><%= field.name %>.size; index++) {
-                        yp_location_t location = cast-><%= field.name %>.locations[index];
-                        rb_ary_push(argv[<%= index %>], yp_location_new(parser, location.start, location.end, source));
-                    }
                     <%- when YARP::ConstantField -%>
                     argv[<%= index %>] = rb_id2sym(constants[cast-><%= field.name %> - 1]);
                     <%- when YARP::ConstantListField -%>

yarp/templates/include/yarp/ast.h.erb

@@ -32,12 +32,6 @@ typedef struct {
     const uint8_t *end;
 } yp_location_t;
 
-typedef struct {
-    yp_location_t *locations;
-    size_t size;
-    size_t capacity;
-} yp_location_list_t;
-
 struct yp_node;
 
 typedef struct yp_node_list {
@@ -95,7 +89,6 @@ typedef struct yp_<%= node.human %> {
     <%= case field
     when YARP::NodeField, YARP::OptionalNodeField then "struct #{field.c_type} *#{field.name}"
     when YARP::NodeListField then "struct yp_node_list #{field.name}"
-    when YARP::LocationListField then "yp_location_list_t #{field.name}"
     when YARP::ConstantField then "yp_constant_id_t #{field.name}"
     when YARP::ConstantListField then "yp_constant_id_list_t #{field.name}"
     when YARP::StringField then "yp_string_t #{field.name}"

yarp/templates/lib/yarp/node.rb.erb

@@ -100,7 +100,7 @@ module YARP
       <%- case field -%>
       <%- when YARP::NodeListField -%>
       inspector << "<%= pointer %><%= field.name %>: #{inspector.list("#{inspector.prefix}<%= preadd %>", <%= field.name %>)}"
-      <%- when YARP::LocationListField, YARP::ConstantListField -%>
+      <%- when YARP::ConstantListField -%>
       inspector << "<%= pointer %><%= field.name %>: #{<%= field.name %>.inspect}\n"
       <%- when YARP::NodeField -%>
       inspector << "<%= pointer %><%= field.name %>:\n"

yarp/templates/lib/yarp/serialize.rb.erb

@@ -185,7 +185,6 @@ module YARP
             when YARP::OptionalNodeField then "load_optional_node"
             when YARP::StringField then "load_string"
             when YARP::NodeListField then "Array.new(load_varint) { load_node }"
-            when YARP::LocationListField then "Array.new(load_varint) { load_location }"
             when YARP::ConstantField then "load_constant"
             when YARP::ConstantListField then "Array.new(load_varint) { load_constant }"
             when YARP::LocationField then "load_location"

yarp/templates/src/node.c.erb

@@ -8,30 +8,6 @@ void yp_node_clear(yp_node_t *node) {
     node->location = location;
 }
 
-// Calculate the size of the token list in bytes.
-static size_t
-yp_location_list_memsize(yp_location_list_t *list) {
-    return sizeof(yp_location_list_t) + (list->capacity * sizeof(yp_location_t));
-}
-
-// Append a token to the given list.
-void
-yp_location_list_append(yp_location_list_t *list, const yp_token_t *token) {
-    if (list->size == list->capacity) {
-        list->capacity = list->capacity == 0 ? 2 : list->capacity * 2;
-        list->locations = (yp_location_t *) realloc(list->locations, sizeof(yp_location_t) * list->capacity);
-    }
-    list->locations[list->size++] = (yp_location_t) { .start = token->start, .end = token->end };
-}
-
-// Free the memory associated with the token list.
-static void
-yp_location_list_free(yp_location_list_t *list) {
-    if (list->locations != NULL) {
-        free(list->locations);
-    }
-}
-
 static void
 yp_node_memsize_node(yp_node_t *node, yp_memsize_t *memsize);
 
@@ -95,8 +71,6 @@ yp_node_destroy(yp_parser_t *parser, yp_node_t *node) {
             yp_string_free(&cast-><%= field.name %>);
             <%- when YARP::NodeListField -%>
             yp_node_list_free(parser, &cast-><%= field.name %>);
-            <%- when YARP::LocationListField -%>
-            yp_location_list_free(&cast-><%= field.name %>);
             <%- when YARP::ConstantListField -%>
             yp_constant_id_list_free(&cast-><%= field.name %>);
             <%- else -%>
@@ -141,8 +115,6 @@ yp_node_memsize_node(yp_node_t *node, yp_memsize_t *memsize) {
             memsize->memsize += yp_string_memsize(&cast-><%= field.name %>);
             <%- when YARP::NodeListField -%>
             yp_node_list_memsize(&cast-><%= field.name %>, memsize);
-            <%- when YARP::LocationListField -%>
-            memsize->memsize += yp_location_list_memsize(&cast-><%= field.name %>);
             <%- when YARP::ConstantListField -%>
             memsize->memsize += yp_constant_id_list_memsize(&cast-><%= field.name %>);
             <%- else -%>

yarp/templates/src/prettyprint.c.erb

@@ -45,13 +45,6 @@ prettyprint_node(yp_buffer_t *buffer, yp_parser_t *parser, yp_node_t *node) {
                 prettyprint_node(buffer, parser, (yp_node_t *) ((yp_<%= node.human %>_t *) node)-><%= field.name %>.nodes[index]);
             }
             yp_buffer_append_str(buffer, "]", 1);
-            <%- when YARP::LocationListField -%>
-            yp_buffer_append_str(buffer, "[", 1);
-            for (uint32_t index = 0; index < ((yp_<%= node.human %>_t *)node)-><%= field.name %>.size; index++) {
-                if (index != 0) yp_buffer_append_str(buffer, ", ", 2);
-                prettyprint_location(buffer, parser, &((yp_<%= node.human %>_t *)node)-><%= field.name %>.locations[index]);
-            }
-            yp_buffer_append_str(buffer, "]", 1);
             <%- when YARP::ConstantField -%>
             char <%= field.name %>_buffer[12];
             snprintf(<%= field.name %>_buffer, sizeof(<%= field.name %>_buffer), "%u", ((yp_<%= node.human %>_t *)node)-><%= field.name %>);

yarp/templates/src/serialize.c.erb

@@ -86,12 +86,6 @@ yp_serialize_node(yp_parser_t *parser, yp_node_t *node, yp_buffer_t *buffer) {
             for (uint32_t index = 0; index < <%= field.name %>_size; index++) {
                 yp_serialize_node(parser, (yp_node_t *) ((yp_<%= node.human %>_t *)node)-><%= field.name %>.nodes[index], buffer);
             }
-            <%- when YARP::LocationListField -%>
-            uint32_t <%= field.name %>_size = yp_sizet_to_u32(((yp_<%= node.human %>_t *)node)-><%= field.name %>.size);
-            yp_buffer_append_u32(buffer, <%= field.name %>_size);
-            for (uint32_t index = 0; index < <%= field.name %>_size; index++) {
-                yp_serialize_location(parser, &((yp_<%= node.human %>_t *)node)-><%= field.name %>.locations[index], buffer);
-            }
             <%- when YARP::ConstantField -%>
             yp_buffer_append_u32(buffer, yp_sizet_to_u32(((yp_<%= node.human %>_t *)node)-><%= field.name %>));
             <%- when YARP::ConstantListField -%>

yarp/templates/template.rb

@@ -73,17 +73,6 @@ def java_type
     end
   end
 
-  # This represents a field on a node that is a list of locations.
-  class LocationListField < Field
-    def rbs_class
-      "Array[Location]"
-    end
-
-    def java_type
-      "Location[]"
-    end
-  end
-
   # This represents a field on a node that is the ID of a string interned
   # through the parser's constant pool.
   class ConstantField < Field
@@ -205,7 +194,6 @@ def field_type_for(name)
       when "node?"      then OptionalNodeField
       when "node[]"     then NodeListField
       when "string"     then StringField
-      when "location[]" then LocationListField
       when "constant"   then ConstantField
       when "constant[]" then ConstantListField
       when "location"   then LocationField