refactor: Flatten multiple declarations

Author: MarcellPerger1

parser/astgen/ast_node.py

@@ -100,10 +100,11 @@ class AstDeclNode(AstNode):
     name = 'var_decl'
     scope: VarDeclScope
     type: VarType
-    decls: list[tuple[AstIdent, AstNode | None]]
+    ident: AstIdent
+    value: AstNode | None
 
     def _walk_members(self, fn: WalkerFnT):
-        self.walk_multiple_objects(fn, (self.decls,))
+        self.walk_multiple_objects(fn, (self.ident, self.value))
 
 
 @dataclass

parser/astgen/astgen.py

@@ -134,14 +134,17 @@ def _walk_smt(self, smt: AnyNode) -> list[AstNode]:
                 f"the root level.", smt.region)
 
     def _walk_var_decl(self, smt: DeclNode):
-        decls = [(self._walk_ident(d.ident),
-                  None if d.value is None else self._walk_expr(d.value))
-                 for d in smt.decl_list.decls]
         scope = (VarDeclScope.LET if isinstance(smt.decl_scope, DeclScope_Let)
                  else VarDeclScope.GLOBAL)
         tp = (VarType.LIST if isinstance(smt.decl_type, DeclType_List)
               else VarType.VARIABLE)
-        return [AstDeclNode(smt.region, scope, tp, decls)]
+        return [self._walk_single_decl(d, scope, tp) for d in smt.decl_list.decls]
+
+    def _walk_single_decl(self, d: DeclItemNode, scope: VarDeclScope, tp: VarType):
+        return AstDeclNode(
+            region_union(d.ident, d.value),
+            scope, tp, self._walk_ident(d.ident),
+            None if d.value is None else self._walk_expr(d.value))
 
     def _walk_assign_left(self, lhs: AnyNode) -> AstNode:
         if isinstance(lhs, IdentNode):

parser/common/common.py

@@ -16,6 +16,8 @@ class HasRegion:
 def region_union(*args: RegionUnionArgT):
     regs = []
     for loc in args:
+        if loc is None:
+            continue
         if getattr(loc, 'region', None) is not None:  # Duck-type HasRegion
             loc = loc.region
         if isinstance(loc, StrRegion):