glib: GStringBuilder by construction always returns an UTF-8 string and never a NULL pointer

Author: sdroege

glib/src/gstring.rs

@@ -440,6 +440,21 @@ impl GString {
     pub unsafe fn from_ptr_lossy<'a>(ptr: *const c_char) -> Cow<'a, GStr> {
         GStr::from_ptr_lossy(ptr)
     }
+
+    // rustdoc-stripper-ignore-next
+    /// Wraps a raw C string with a safe GLib string wrapper. The provided C string **must** be
+    /// nul-terminated. All constraints from [`std::ffi::CStr::from_ptr`] also apply here.
+    ///
+    /// `len` is the length without the nul-terminator, i.e. if `len == 0` is passed then `*ptr`
+    /// must be the nul-terminator.
+    pub unsafe fn from_ptr_and_len_unchecked(ptr: *const c_char, len: usize) -> Self {
+        assert!(!ptr.is_null());
+
+        GString(Inner::Foreign {
+            ptr: ptr::NonNull::new_unchecked(ptr as *mut _),
+            len,
+        })
+    }
 }
 
 impl IntoGlibPtr<*mut c_char> for GString {

glib/src/gstring_builder.rs

@@ -116,10 +116,6 @@ impl GStringBuilder {
 
     // rustdoc-stripper-ignore-next
     /// Returns `&str` slice.
-    ///
-    /// # Panics
-    ///
-    /// If the string builder contains invalid UTF-8 this function panics.
     pub fn as_str(&self) -> &str {
         unsafe {
             let ptr: *const u8 = self.inner.str as _;
@@ -128,21 +124,17 @@ impl GStringBuilder {
                 return "";
             }
             let slice = slice::from_raw_parts(ptr, len);
-            std::str::from_utf8(slice).unwrap()
+            std::str::from_utf8_unchecked(slice)
         }
     }
 
     // rustdoc-stripper-ignore-next
     /// Returns `&str` slice.
-    ///
-    /// # Panics
-    ///
-    /// If the string builder contains invalid UTF-8 this function panics.
     #[must_use = "String returned from the builder should probably be used"]
     pub fn into_string(self) -> crate::GString {
         unsafe {
             let s = mem::ManuallyDrop::new(self);
-            crate::GString::from_glib_full_num(s.inner.str, s.inner.len)
+            crate::GString::from_ptr_and_len_unchecked(s.inner.str, s.inner.len)
         }
     }
 }