bevyengine/bevy · error · ParseAssetPathError

Asset label must not contain a `://` substring

Error message

Asset label must not contain a `://` substring

What it means

ParseAssetPathError variant for a label containing the source delimiter '://' (e.g. 'file.test#label://x'). Since '://' marks the start of a source prefix, such a label cannot be parsed unambiguously and is rejected.

Source

Thrown at crates/bevy_asset/src/path.rs:89

        if let AssetSourceId::Name(name) = self.source() {
            write!(f, "{name}://")?;
        }
        write!(f, "{}", self.path.display())?;
        if let Some(label) = &self.label {
            write!(f, "#{label}")?;
        }
        Ok(())
    }
}

/// An error that occurs when parsing a string type to create an [`AssetPath`] fails, such as during [`AssetPath::parse`].
#[derive(Error, Debug, PartialEq, Eq)]
pub enum ParseAssetPathError {
    /// Error that occurs when the [`AssetPath::source`] section of a path string contains the [`AssetPath::label`] delimiter `#`. E.g. `bad#source://file.test`.
    #[error("Asset source must not contain a `#` character")]
    InvalidSourceSyntax,
    /// Error that occurs when the [`AssetPath::label`] section of a path string contains the [`AssetPath::source`] delimiter `://`. E.g. `source://file.test#bad://label`.
    #[error("Asset label must not contain a `://` substring")]
    InvalidLabelSyntax,
    /// Error that occurs when a path string has an [`AssetPath::source`] delimiter `://` with no characters preceding it. E.g. `://file.test`.
    #[error("Asset source must be at least one character. Either specify the source before the '://' or remove the `://`")]
    MissingSource,
    /// Error that occurs when a path string has an [`AssetPath::label`] delimiter `#` with no characters succeeding it. E.g. `file.test#`
    #[error("Asset label must be at least one character. Either specify the label after the '#' or remove the '#'")]
    MissingLabel,
}

impl<'a> AssetPath<'a> {
    /// Creates a new [`AssetPath`] from a string in the asset path format:
    /// * An asset at the root: `"scene.gltf"`
    /// * An asset nested in some folders: `"some/path/scene.gltf"`
    /// * An asset with a "label": `"some/path/scene.gltf#Mesh0"`
    /// * An asset with a custom "source": `"custom://some/path/scene.gltf#Mesh0"`
    ///
    /// Prefer [`From<'static str>`] for static strings, as this will prevent allocations
    /// and reference counting for [`AssetPath::into_owned`].

View on GitHub (pinned to 8d743eb7dc)

Solutions

1. Remove the '://' sequence from the subasset label
2. Check for a malformed path where the label and source sections are swapped
3. Rename the subasset label to a delimiter-free string

When it happens

Trigger: Thrown at crates/bevy_asset/src/path.rs:89 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of bevyengine/bevy@8d743eb7dc (2026-08-20). Data as JSON: /api/errors/fe916a2343e2c018. Report an issue: GitHub.