bevyengine/bevy · error · ParseAssetPathError

Asset source must not contain a `#` character

Error message

Asset source must not contain a `#` character

What it means

ParseAssetPathError::InvalidSourceSyntax: while parsing an asset path string, the source section (the part before ://) contained the label delimiter '#' (e.g. 'bad#source://file.test'). The source name must be a plain identifier without '#'.

Source

Thrown at crates/bevy_asset/src/path.rs:86

impl<'a> Display for AssetPath<'a> {
    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
        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"`

View on GitHub (pinned to 8d743eb7dc)

Solutions

  1. Remove the '#' from the asset source name in the path string
  2. Move any label to the end of the path after a single '#'
  3. Escape or rename source names that legitimately contain special characters
Defensive patterns

Strategy: validation

When it happens

Trigger: Thrown at crates/bevy_asset/src/path.rs:86 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/599b9eafe2dae7c1. Report an issue: GitHub.