Enum Error 

pub enum Error {
    FileRead(Error),
    JsonParse(Error),
    CreateDir(Error),
    FileWrite(Error),
    ItemNotFound(String),
    InvalidDirectory(String),
    NoJsonFiles(PathBuf),
    DuplicateCrate(String),
    NoCrateName(PathBuf),
    ProgressBarTemplate(TemplateError),
    SourceLocator(String),
    SourceParser(String),
    SourceCollector(String),
}

Errors that can occur during documentation generation.

Each variant includes:

• A human-readable error message
• A diagnostic code (e.g., docs_md::io::read)
• Optional help text for resolution
• The underlying source error (where applicable)

Variants

FileRead(Error)

Failed to read a file from disk.

This typically occurs when:

• The file doesn’t exist
• The process lacks read permissions
• The path is invalid

JsonParse(Error)

Failed to parse the rustdoc JSON file.

This can happen when:

• The file is not valid JSON
• The JSON schema doesn’t match rustdoc-types expectations
• The file is from an incompatible rustdoc version

CreateDir(Error)

Failed to create the output directory.

This typically occurs when:

• The parent directory doesn’t exist
• The process lacks write permissions
• The path is invalid or too long

FileWrite(Error)

Failed to write a markdown file.

This typically occurs when:

• The output directory is not writable
• The disk is full
• The file is locked by another process

ItemNotFound(String)

An item ID was not found in the crate’s index.

The rustdoc JSON index should contain all referenced items. This error indicates data inconsistency, possibly from:

• Corrupted JSON
• Incompatible rustdoc-types version
• Items removed during filtering

The string contains the ID that was not found.

InvalidDirectory(String)

The specified directory path is invalid or inaccessible.

This typically occurs when:

• The path doesn’t exist
• The path is a file, not a directory
• The process lacks read permissions

NoJsonFiles(PathBuf)

No rustdoc JSON files were found in the specified directory.

The directory should contain .json files generated by rustdoc with the --output-format json flag.

DuplicateCrate(String)

Multiple crates with the same name were found.

Each JSON file should represent a unique crate. This error indicates duplicate crate names in the input directory.

NoCrateName(PathBuf)

Could not determine the crate name from a JSON file.

The rustdoc JSON format should include a root item with the crate name. This error indicates a malformed file.

ProgressBarTemplate(TemplateError)

Failed to create a progress bar with the given template.

This indicates an invalid progress bar template string. Since templates are compile-time constants, this error typically indicates a programming error.

SourceLocator(String)

Failed to locate crate source in the Cargo registry.

This occurs when:

• The crate is not downloaded in ~/.cargo/registry/src/
• The specified version doesn’t exist
• The registry path is misconfigured

SourceParser(String)

Failed to parse Rust source code with syn.

This occurs when:

• The source file contains invalid Rust syntax
• The file cannot be read
• Module resolution fails

SourceCollector(String)

Failed to collect dependency sources.

This occurs when:

• Cargo metadata cannot be loaded
• The registry path doesn’t exist
• File copy operations fail
• Too many .source_* directories exist

Trait Implementations

impl Debug for Error

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Diagnostic for Error

fn code(&self) -> Option<Box<dyn Display + '_>>

Unique diagnostic code that can be used to look up more information about this Diagnostic. Ideally also globally unique, and documented in the toplevel crate’s documentation for easy searching. Rust path format (foo::bar::baz) is recommended, but more classic codes like E0123 or enums will work just fine.

fn help(&self) -> Option<Box<dyn Display + '_>>

Additional help text related to this Diagnostic. Do you have any advice for the poor soul who’s just run into this issue?

fn severity(&self) -> Option<Severity>

Diagnostic severity. This may be used by ReportHandlers to change the display format of this diagnostic.

fn url<'a>(&'a self) -> Option<Box<dyn Display + 'a>>

URL to visit for a more detailed explanation/help about this Diagnostic.

fn source_code(&self) -> Option<&dyn SourceCode>

Source code to apply this Diagnostic’s Diagnostic::labels to.

fn labels(&self) -> Option<Box<dyn Iterator<Item = LabeledSpan> + '_>>

Labels to apply to this Diagnostic’s Diagnostic::source_code

fn related<'a>( &'a self, ) -> Option<Box<dyn Iterator<Item = &'a dyn Diagnostic> + 'a>>

Additional related Diagnostics.

fn diagnostic_source(&self) -> Option<&dyn Diagnostic>

The cause of the error.

impl Display for Error

fn fmt(&self, __formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Error for Error

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0: use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0: replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.