comparison rust/hg-core/src/revlog/index.rs @ 49930:e98fd81bb151

rust-clippy: fix most warnings in `hg-core`

All of these are simple changes that for the most part are clear improvements
and the rest are at most equivalent.

The remaining warnings have to be fixed either with a bigger refactor like for
the nested "revlog" module, or in the dependency `bytes-cast`, which we own.

This will be done sometime in the future.

49929:5f1cd6839c69

/// Corresponds to the high bits of `_format_flags` in python
impl IndexHeaderFlags {
    /// Corresponds to FLAG_INLINE_DATA in python
    pub fn is_inline(self) -> bool {
        return self.flags & 1 != 0;
    }
    /// Corresponds to FLAG_GENERALDELTA in python
    pub fn uses_generaldelta(self) -> bool {
        return self.flags & 2 != 0;
    }
}

/// Corresponds to the INDEX_HEADER structure,
/// which is parsed as a `header` variable in `_loadindex` in `revlog.py`
impl IndexHeader {
    fn format_flags(&self) -> IndexHeaderFlags {
        // No "unknown flags" check here, unlike in python. Maybe there should
        // be.
        return IndexHeaderFlags {
            flags: BigEndian::read_u16(&self.header_bytes[0..2]),
        };
    }

    /// The only revlog version currently supported by rhg.
    const REVLOGV1: u16 = 1;

    /// Corresponds to `_format_version` in Python.
    fn format_version(&self) -> u16 {
        return BigEndian::read_u16(&self.header_bytes[2..4]);
    }

    const EMPTY_INDEX_HEADER: IndexHeader = IndexHeader {
        // We treat an empty file as a valid index with no entries.
        // Here we make an arbitrary choice of what we assume the format of the

        // `revlog.py`, `_loadindex`
        header_bytes: [0, 3, 0, 1],
    };

    fn parse(index_bytes: &[u8]) -> Result<IndexHeader, HgError> {
        if index_bytes.len() == 0 {
            return Ok(IndexHeader::EMPTY_INDEX_HEADER);
        }
        if index_bytes.len() < 4 {
            return Err(HgError::corrupted(
                "corrupted revlog: can't read the index format header",
            ));
        }
        return Ok(IndexHeader {
            header_bytes: {
                let bytes: [u8; 4] =
                    index_bytes[0..4].try_into().expect("impossible");
                bytes
            },
        });
    }
}

/// A Revlog index
pub struct Index {

                    bytes,
                    offsets: Some(offsets),
                    uses_generaldelta,
                })
            } else {
                Err(HgError::corrupted("unexpected inline revlog length")
                    .into())
            }
        } else {
            Ok(Self {
                bytes,
                offsets: None,

            .is_first(true)
            .with_general_delta(false)
            .with_inline(false)
            .build();

        assert_eq!(is_inline(&bytes), false);
        assert_eq!(uses_generaldelta(&bytes), false);
    }

    #[test]
    fn flags_when_inline_flag_test() {
        let bytes = IndexEntryBuilder::new()
            .is_first(true)
            .with_general_delta(false)
            .with_inline(true)
            .build();

        assert_eq!(is_inline(&bytes), true);
        assert_eq!(uses_generaldelta(&bytes), false);
    }

    #[test]
    fn flags_when_inline_and_generaldelta_flags_test() {
        let bytes = IndexEntryBuilder::new()
            .is_first(true)
            .with_general_delta(true)
            .with_inline(true)
            .build();

        assert_eq!(is_inline(&bytes), true);
        assert_eq!(uses_generaldelta(&bytes), true);
    }

    #[test]
    fn test_offset() {
        let bytes = IndexEntryBuilder::new().with_offset(1).build();

49930:e98fd81bb151

/// Corresponds to the high bits of `_format_flags` in python
impl IndexHeaderFlags {
    /// Corresponds to FLAG_INLINE_DATA in python
    pub fn is_inline(self) -> bool {
        self.flags & 1 != 0
    }
    /// Corresponds to FLAG_GENERALDELTA in python
    pub fn uses_generaldelta(self) -> bool {
        self.flags & 2 != 0
    }
}

/// Corresponds to the INDEX_HEADER structure,
/// which is parsed as a `header` variable in `_loadindex` in `revlog.py`
impl IndexHeader {
    fn format_flags(&self) -> IndexHeaderFlags {
        // No "unknown flags" check here, unlike in python. Maybe there should
        // be.
        IndexHeaderFlags {
            flags: BigEndian::read_u16(&self.header_bytes[0..2]),
        }
    }

    /// The only revlog version currently supported by rhg.
    const REVLOGV1: u16 = 1;

    /// Corresponds to `_format_version` in Python.
    fn format_version(&self) -> u16 {
        BigEndian::read_u16(&self.header_bytes[2..4])
    }

    const EMPTY_INDEX_HEADER: IndexHeader = IndexHeader {
        // We treat an empty file as a valid index with no entries.
        // Here we make an arbitrary choice of what we assume the format of the

        // `revlog.py`, `_loadindex`
        header_bytes: [0, 3, 0, 1],
    };

    fn parse(index_bytes: &[u8]) -> Result<IndexHeader, HgError> {
        if index_bytes.is_empty() {
            return Ok(IndexHeader::EMPTY_INDEX_HEADER);
        }
        if index_bytes.len() < 4 {
            return Err(HgError::corrupted(
                "corrupted revlog: can't read the index format header",
            ));
        }
        Ok(IndexHeader {
            header_bytes: {
                let bytes: [u8; 4] =
                    index_bytes[0..4].try_into().expect("impossible");
                bytes
            },
        })
    }
}

/// A Revlog index
pub struct Index {

                    bytes,
                    offsets: Some(offsets),
                    uses_generaldelta,
                })
            } else {
                Err(HgError::corrupted("unexpected inline revlog length"))
            }
        } else {
            Ok(Self {
                bytes,
                offsets: None,

            .is_first(true)
            .with_general_delta(false)
            .with_inline(false)
            .build();

        assert!(!is_inline(&bytes));
        assert!(!uses_generaldelta(&bytes));
    }

    #[test]
    fn flags_when_inline_flag_test() {
        let bytes = IndexEntryBuilder::new()
            .is_first(true)
            .with_general_delta(false)
            .with_inline(true)
            .build();

        assert!(is_inline(&bytes));
        assert!(!uses_generaldelta(&bytes));
    }

    #[test]
    fn flags_when_inline_and_generaldelta_flags_test() {
        let bytes = IndexEntryBuilder::new()
            .is_first(true)
            .with_general_delta(true)
            .with_inline(true)
            .build();

        assert!(is_inline(&bytes));
        assert!(uses_generaldelta(&bytes));
    }

    #[test]
    fn test_offset() {
        let bytes = IndexEntryBuilder::new().with_offset(1).build();