Rename code to call

Co-authored-by: Davis Vaughan <davis@posit.co>

Author: lionel-

crates/harp/src/error.rs

@@ -23,7 +23,7 @@ pub enum Error {
         message: String,
     },
     TryCatchError {
-        code: Option<String>,
+        call: Option<String>,
         message: String,
         class: Option<Vec<String>>,
         r_trace: String,
@@ -98,14 +98,14 @@ impl fmt::Display for Error {
             },
 
             Error::TryCatchError {
-                code,
+                call,
                 message,
                 r_trace,
                 rust_trace,
                 ..
             } => {
-                if let Some(code) = code {
-                    let code = truncate_lines(code.to_owned(), 50);
+                if let Some(call) = call {
+                    let code = truncate_lines(call.to_owned(), 50);
                     write!(f, "Error evaluating '{code}': {message}")?;
                 } else {
                     write!(f, "{message}")?;

crates/harp/src/exec.rs

@@ -95,8 +95,8 @@ impl RFunction {
 pub fn try_eval(expr: SEXP, env: SEXP) -> crate::Result<RObject> {
     let mut res = try_catch(|| unsafe { Rf_eval(expr, env) }).map(RObject::from);
 
-    if let Err(Error::TryCatchError { ref mut code, .. }) = res {
-        *code = Some(unsafe { r_stringify(expr, "\n")? });
+    if let Err(Error::TryCatchError { ref mut call, .. }) = res {
+        *call = Some(unsafe { r_stringify(expr, "\n")? });
     }
 
     res
@@ -237,7 +237,7 @@ where
             let rust_trace = std::backtrace::Backtrace::force_capture();
 
             *(data.res) = Some(Err(Error::TryCatchError {
-                code: call,
+                call,
                 message,
                 class,
                 r_trace,