Add Context::set_var

src/context/mod.rs

@@ -5,8 +5,8 @@ pub use builder::*;
 pub use command_group_config::CommandGroupConfig;
 use nu_protocol::{
     ast::{Block, Call},
-    engine::{EngineState, Stack},
-    PipelineData, Span,
+    engine::{EngineState, Stack, StateWorkingSet},
+    PipelineData, Span, Type,
 };
 
 use crate::{
@@ -70,6 +70,21 @@ impl Context {
         self.stack.get_var(*var_id, Span::new(0, 0)).ok()
     }
 
+    /// Define a variable on the stack
+    pub fn set_var<S: AsRef<str>>(
+        &mut self,
+        name: S,
+        value: nu_protocol::Value,
+    ) -> CrateResult<()> {
+        let name = name.as_ref();
+        let dollar_name = format!("${name}").as_bytes().to_vec();
+        let mut state = StateWorkingSet::new(&self.engine_state);
+        let var_id = state.add_variable(dollar_name, Span::new(0, 0), Type::Any, true);
+        self.engine_state.merge_delta(state.delta)?;
+        self.stack.add_var(var_id, value);
+        Ok(())
+    }
+
     /// Returns if the given function exists in the context
     pub fn has_fn<S: AsRef<str>>(&mut self, name: S) -> bool {
         self.engine_state

tests/test_eval.rs

@@ -24,6 +24,16 @@ fn it_returns_variables() {
     assert_eq!(val.as_string().unwrap(), String::from("world"))
 }
 
+#[test]
+fn it_sets_variables() {
+    let mut ctx = get_context();
+    ctx.set_var("world", "world".into_value()).unwrap();
+    ctx.eval_raw(r#"let hello = $world"#, PipelineData::empty())
+        .unwrap();
+    let val = ctx.get_var("hello").expect("No variable returned");
+    assert_eq!(val.as_string().unwrap(), String::from("world"))
+}
+
 #[derive(RustyValue)]
 struct TestArg {
     foo: String,
@@ -35,12 +45,12 @@ fn it_executes_functions() {
     let mut ctx = get_context();
     ctx.eval_raw(
         r#"
-    
+
         def hello [] {
             echo "Hello World from this script";
             echo # dummy echo so I don't have to print the output
-        }        
-        
+        }
+
     "#,
         PipelineData::empty(),
     )