fix ErrorContext::peak always returning Ok(())

nixide/src/errors/context.rs

@@ -28,7 +28,6 @@ use std::ptr::NonNull;
 use super::{NixError, NixideResult};
 use crate::stdext::{AsCPtr as _, CCharPtrExt as _};
 use crate::sys;
-use crate::util::panic_issue_call_failed;
 use crate::util::wrap;
 use crate::util::wrappers::AsInnerPtr;
 
@@ -100,7 +99,7 @@ impl Into<NixideResult<()>> for &ErrorContext {
         };
         let msg = match self.get_msg() {
             Some(msg) => msg,
-            None => return Ok(()),
+            None => String::new(),
         };
 
         let err = match inner {
@@ -109,13 +108,8 @@ impl Into<NixideResult<()>> for &ErrorContext {
             sys::NixErr::Overflow => NixError::Overflow,
             sys::NixErr::Key => NixError::KeyNotFound(None),
             sys::NixErr::NixError => NixError::ExprEval {
-                name: self
-                    .get_nix_err_name()
-                    .unwrap_or_else(|| panic_issue_call_failed!()),
-
-                info_msg: self
-                    .get_nix_err_info_msg()
-                    .unwrap_or_else(|| panic_issue_call_failed!()),
+                name: self.get_nix_err_name().unwrap(),
+                info_msg: self.get_nix_err_info_msg().unwrap_or_else(|| String::new()),
             },
 
             // XXX: WARNING: Recoverable only exists in later version of Nix
@@ -217,7 +211,7 @@ impl ErrorContext {
     ///
     /// This function **never fails**.
     ///
-    fn get_err(&self) -> Option<sys::NixErr> {
+    pub fn get_err(&self) -> Option<sys::NixErr> {
         match unsafe { sys::nix_err_code(self.as_ptr()) } {
             sys::NixErr::Ok => None,
             err => Some(err),
@@ -254,7 +248,7 @@ impl ErrorContext {
     /// Hence we can just test whether the returned pointer is a `NULL` pointer,
     /// and avoid passing in a [NixCContext] struct.
     ///
-    fn get_msg(&self) -> Option<String> {
+    pub fn get_msg(&self) -> Option<String> {
         // NOTE: an Err here only occurs when `self.get_code() == Ok(())`
         let mut n: c_uint = 0;
         let result = wrap::nix_fn!(|ctx: &ErrorContext| unsafe {