feat(closure): allow capture in nested scopes

Author: SuperFola

CHANGELOG.md

@@ -103,6 +103,7 @@
 - re-enabled the AST optimizer, only used for the main `arkscript` executable (not enabled when embedding arkscript, so that one can grab variables from the VM)
 - loops have their own scope: variables created inside a loop won't leak outside it
 - upgraded fmtlib to 11.1.3-13
+- allow capture in nested scope (before it was targeting only the current scope)
 
 ### Removed
 - removed unused `NodeType::Closure`

include/Ark/VM/VM.hpp

@@ -186,8 +186,8 @@ namespace Ark
         //               instruction helpers
         // ================================================
 
-        inline Value* loadSymbol(uint16_t id, internal::ExecutionContext& context);
-        inline Value* loadConstAsPtr(uint16_t id) const;
+        [[nodiscard]] inline Value* loadSymbol(uint16_t id, internal::ExecutionContext& context);
+        [[nodiscard]] inline Value* loadConstAsPtr(uint16_t id) const;
         inline void store(uint16_t id, const Value* val, internal::ExecutionContext& context);
         inline void setVal(uint16_t id, const Value* val, internal::ExecutionContext& context);
 

src/arkreactor/VM/VM.cpp

@@ -556,7 +556,7 @@ namespace Ark
                         if (!context.saved_scope)
                             context.saved_scope = Scope();
 
-                        Value* ptr = (context.locals.back())[arg];
+                        Value* ptr = findNearestVariable(arg, context);
                         if (!ptr)
                             throwVMError(ErrorKind::Scope, fmt::format("Couldn't capture `{}' as it is currently unbound", m_state.m_symbols[arg]));
                         else

tests/unittests/resources/LangSuite/builtins-tests.ark

@@ -5,31 +5,43 @@
 (let closure (fun (&foo) ()))
 
 (test:suite builtin {
-    (test:eq (type []) "List")
-    (test:eq (type true) "Bool")
-    (test:eq (type false) "Bool")
-    (test:eq (type nil) "Nil")
-    (test:eq (type 1) "Number")
-    (test:eq (type "hello") "String")
-    (test:eq (type print) "CProc")
-    (test:eq (type foo) "Function")
-    (test:eq (type closure) "Closure")
-
-    (test:expect (not (io:fileExists? "test.txt")))
-    (io:writeFile "test.txt" "hello, world!")
-    (test:expect (io:fileExists? "test.txt"))
-    (test:eq (io:readFile "test.txt") "hello, world!")
-    (io:appendToFile "test.txt" "bis")
-    (test:eq (io:readFile "test.txt") "hello, world!bis")
-    (test:expect (> (len (io:listFiles "./")) 0))
-    (test:expect (not (io:dir? "test.txt")))
-    (test:expect (not (io:fileExists? "temp")))
-    (io:makeDir "temp")
-    (test:expect (io:fileExists? "temp"))
-    (test:expect (io:dir? "temp"))
-    (let old (time))
-    (sys:sleep 1)
-    (test:expect (< old (time)))
+    (test:case "types" {
+        (test:eq (type []) "List")
+        (test:eq (type true) "Bool")
+        (test:eq (type false) "Bool")
+        (test:eq (type nil) "Nil")
+        (test:eq (type 1) "Number")
+        (test:eq (type "hello") "String")
+        (test:eq (type print) "CProc")
+        (test:eq (type foo) "Function")
+        (test:eq (type closure) "Closure") })
+
+    (test:case "closures" {
+        (mut keep true)
+        (mut foo nil)
+        (while keep {
+            (set foo (fun (&keep) keep))
+            (set keep false) })
+        (test:expect foo.keep "capture inside a deeper scope works") })
+
+    (test:case "files" {
+        (test:expect (not (io:fileExists? "test.txt")))
+        (io:writeFile "test.txt" "hello, world!")
+        (test:expect (io:fileExists? "test.txt"))
+        (test:eq (io:readFile "test.txt") "hello, world!")
+        (io:appendToFile "test.txt" "bis")
+        (test:eq (io:readFile "test.txt") "hello, world!bis")
+        (test:expect (> (len (io:listFiles "./")) 0))
+        (test:expect (not (io:dir? "test.txt")))
+        (test:expect (not (io:fileExists? "temp")))
+        (io:makeDir "temp")
+        (test:expect (io:fileExists? "temp"))
+        (test:expect (io:dir? "temp")) })
+
+    (test:case "time" {
+        (let old (time))
+        (sys:sleep 1)
+        (test:expect (< old (time))) })
 
     (mut rands [])
     (mut i 0)