fix empty blocks

adana-script/src/parser.rs

@@ -889,7 +889,13 @@ where
     F: Fn(&str) -> Res<Vec<Value>>,
 {
     move |s| {
-        preceded(tag_no_space("{"), terminated(&parser, tag_no_space("}")))(s)
+        map(
+            preceded(
+                tag_no_space("{"),
+                terminated(opt(&parser), tag_no_space("}")),
+            ),
+            |exprs| if let Some(exprs) = exprs { exprs } else { vec![] },
+        )(s)
     }
 }
 

adana-script/src/tests/empty_block.rs

@@ -0,0 +1,46 @@
+use std::collections::BTreeMap;
+
+use crate::compute;
+
+use adana_script_core::primitive::Primitive;
+#[test]
+fn empty_while() {
+    let expr = r#"
+         x =1024
+         y = 3
+         while (x!=1024) {}
+         x
+       "#;
+    let mut ctx = BTreeMap::new();
+    let res = compute(expr, &mut ctx, "N/A").unwrap();
+    assert_eq!(Primitive::Int(1024), ctx["x"].read().unwrap().clone());
+    assert_eq!(Primitive::Int(1024), res);
+}
+#[test]
+fn empty_if() {
+    let expr = r#"
+         x =1024
+         y = 3
+         if (x==1024) {}
+         if (x==1024) {}else {}
+         x
+       "#;
+    let mut ctx = BTreeMap::new();
+    let res = compute(expr, &mut ctx, "N/A").unwrap();
+    assert_eq!(Primitive::Int(1024), ctx["x"].read().unwrap().clone());
+    assert_eq!(Primitive::Int(1024), res);
+}
+
+#[test]
+fn empty_for() {
+    let expr = r#"
+         x =1024
+         y = 3
+         for i in 0..x {}
+         x
+    "#;
+    let mut ctx = BTreeMap::new();
+    let res = compute(expr, &mut ctx, "N/A").unwrap();
+    assert_eq!(Primitive::Int(1024), ctx["x"].read().unwrap().clone());
+    assert_eq!(Primitive::Int(1024), res);
+}

adana-script/src/tests/mod.rs

@@ -4,6 +4,7 @@ mod builtin;
 mod chaining;
 mod drop;
 mod dynload;
+mod empty_block;
 mod examples;
 mod file;
 mod foreach;