test: update test cases for lexical scoping and closure behavior

Modify test cases in r1, r2, and r3 directories to clarify lexical scoping and closure scenarios, including:
- Updating variable assignment and function naming
- Refining comments to better explain test expectations
- Ensuring consistent test case structure

Author: ryan-gang

test_programs/r1/1.lox

@@ -8,5 +8,5 @@ fun foo() {
 }
 
 foo(); // expect: outer
-var a = "inner";
+a = "inner";
 foo(); // expect: inner

test_programs/r1/4.lox

@@ -16,5 +16,5 @@ var counter1 = makeCounter();
 counter1(); // Should print 1
 counter1(); // Should print 2
 
-var count = 0;
-counter1(); // Should print 1
+count = 0; // Global count is reset
+counter1(); // Should again print 1

test_programs/r2/3.lox

@@ -16,7 +16,7 @@ var add10 = makeAdder(10);
 print add5(3); // expect: 8
 print add10(3); // expect: 13
 
-// Redefine the outer function but keep the closures
+// Redefine the outer function
 fun makeAdder(x) {
   counter = counter + 1;
   fun add(y) {

test_programs/r3/1.lox

@@ -3,11 +3,11 @@ expected_error_type: none
 ---
 var variable = "global";
 {
-  fun printer() {
+  fun f() {
     print variable;
   }
 
-  printer(); // expect: global
+  f(); // expect: global
   var variable = "local";
-  printer(); // expect: global
+  f(); // expect: global
 }

test_programs/r3/2.lox

@@ -6,13 +6,13 @@ fun global() {
 }
 
 {
-  fun printer() {
+  fun f() {
     global();
   }
 
-  printer();
+  f();
   fun global() {
     print "local";
   }
-  printer();
+  f();
 }

test_programs/r3/3.lox

@@ -17,6 +17,6 @@ var count = 0;
   counter1(); // Should print 1
   counter1(); // Should print 2
 
-  var count = 0;
+  var count = 0; // This local variable shouldn't affect our counter
   counter1(); // Should print 3
 }