refactor(env): introduce VarName enum to unify nameref resolution API

brush-builtins/src/declare.rs

@@ -4,7 +4,7 @@ use std::{io::Write, sync::LazyLock};
 
 use brush_core::{
     ErrorKind, ExecutionResult, builtins,
-    env::{self, EnvironmentLookup, EnvironmentScope},
+    env::{self, EnvironmentLookup, EnvironmentScope, VarNameExt},
     error,
     parser::ast,
     variables::{
@@ -214,10 +214,9 @@ impl DeclareCommand {
         } else if let Some((_, variable)) = context
             .shell
             .env()
-            .lookup(name.as_str())
-            .bypassing_nameref()
+            .lookup(name.as_str().direct())
             .in_scope(lookup)
-            .get()
+            .get_direct()
         {
             let mut cs = variable.attribute_flags(context.shell);
             if cs.is_empty() {
@@ -344,7 +343,7 @@ impl DeclareCommand {
             .env_mut()
             .lookup_mut(&resolved_name)
             .in_scope(lookup)
-            .get()
+            .get_direct()
         {
             if self.make_associative_array.is_some() {
                 var.convert_to_associative_array()?;
@@ -605,18 +604,14 @@ impl DeclareCommand {
             && context
                 .shell
                 .env()
-                .lookup(name.as_str())
-                .bypassing_nameref()
+                .lookup(name.as_str().direct())
                 .in_scope(lookup)
-                .get()
+                .get_direct()
                 .is_none();
 
         let should_resolve = !explicitly_modifying_nameref_attr && !creating_new_local;
         if should_resolve {
-            let resolved = context
-                .shell
-                .env()
-                .resolve_nameref(name.as_str())?;
+            let resolved = context.shell.env().resolve_nameref(name.as_str())?;
             if resolved.name() != name.as_str() {
                 // For subscripted targets (e.g., ref→arr[2]), resolve to the
                 // base variable name. `declare -x ref` applies the export to

brush-builtins/src/export.rs

@@ -94,16 +94,9 @@ impl ExportCommand {
                     // Check for circular namerefs upfront so we can emit a warning
                     // (env_mut().get_mut() silently swallows the resolution error).
                     if let Err(err) = context.shell.env().resolve_nameref(s)
-                        && matches!(
-                            err.kind(),
-                            error::ErrorKind::CircularNameReference(_)
-                        )
+                        && matches!(err.kind(), error::ErrorKind::CircularNameReference(_))
                     {
-                        writeln!(
-                            context.stderr(),
-                            "{}: warning: {err}",
-                            context.command_name
-                        )?;
+                        writeln!(context.stderr(), "{}: warning: {err}", context.command_name)?;
                     } else if let Some(mut resolved) = context.shell.env_mut().get_mut(s) {
                         if resolved.has_subscript() {
                             // Resolve the nameref to get the full target string for the error.

brush-builtins/src/unset.rs

@@ -2,7 +2,9 @@ use std::borrow::Cow;
 
 use clap::Parser;
 
-use brush_core::{ExecutionResult, Shell, ShellValue, builtins, variables::ShellValueUnsetType};
+use brush_core::{
+    ExecutionResult, Shell, ShellValue, builtins, env::VarNameExt, variables::ShellValueUnsetType,
+};
 
 /// Unset a variable.
 #[derive(Parser)]
@@ -54,15 +56,11 @@ impl builtins::Command for UnsetCommand {
                 let is_nameref = context
                     .shell
                     .env()
-                    .lookup(name.as_str())
-                    .bypassing_nameref()
-                    .get()
+                    .lookup(name.direct())
+                    .get_direct()
                     .is_some_and(|(_, v)| v.is_treated_as_nameref());
                 if is_nameref {
-                    context
-                        .shell
-                        .env_mut()
-                        .unset_bypassing_nameref(name.as_str())?;
+                    context.shell.env_mut().unset(name.direct())?;
                 }
                 // `unset -n` never touches functions or array elements — it
                 // operates only on nameref variables. Skip the rest of the loop.
@@ -120,7 +118,7 @@ fn unset_array_index(
 
     // Check if the resolved target is an associative array (use lookup with the
     // already-resolved name to avoid redundant nameref resolution).
-    let is_assoc_array = if let Some((_, var)) = shell.env().lookup(&resolved).get() {
+    let is_assoc_array = if let Some((_, var)) = shell.env().lookup(&resolved).get_direct() {
         matches!(
             var.value(),
             ShellValue::AssociativeArray(_)
@@ -142,7 +140,7 @@ fn unset_array_index(
     };
 
     // Use lookup_mut with the already-resolved name to avoid redundant nameref resolution.
-    if let Some((_, var)) = shell.env_mut().lookup_mut(&resolved).get() {
+    if let Some((_, var)) = shell.env_mut().lookup_mut(&resolved).get_direct() {
         var.unset_index(index_to_use.as_ref())
     } else {
         Ok(false)