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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 12:41:41 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 12:41:41 +0000
commit10ee2acdd26a7f1298c6f6d6b7af9b469fe29b87 (patch)
treebdffd5d80c26cf4a7a518281a204be1ace85b4c1 /vendor/similar/src/udiff.rs
parentReleasing progress-linux version 1.70.0+dfsg1-9~progress7.99u1. (diff)
downloadrustc-10ee2acdd26a7f1298c6f6d6b7af9b469fe29b87.tar.xz
rustc-10ee2acdd26a7f1298c6f6d6b7af9b469fe29b87.zip
Merging upstream version 1.70.0+dfsg2.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'vendor/similar/src/udiff.rs')
-rw-r--r--vendor/similar/src/udiff.rs359
1 files changed, 359 insertions, 0 deletions
diff --git a/vendor/similar/src/udiff.rs b/vendor/similar/src/udiff.rs
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+//! This module provides unified diff functionality.
+//!
+//! It is available for as long as the `text` feature is enabled which
+//! is enabled by default:
+//!
+//! ```rust
+//! use similar::TextDiff;
+//! # let old_text = "";
+//! # let new_text = "";
+//! let text_diff = TextDiff::from_lines(old_text, new_text);
+//! print!("{}", text_diff
+//! .unified_diff()
+//! .context_radius(10)
+//! .header("old_file", "new_file"));
+//! ```
+//!
+//! # Unicode vs Bytes
+//!
+//! The [`UnifiedDiff`] type supports both unicode and byte diffs for all
+//! types compatible with [`DiffableStr`]. You can pick between the two
+//! versions by using the [`Display`](std::fmt::Display) implementation or
+//! [`UnifiedDiff`] or [`UnifiedDiff::to_writer`].
+//!
+//! The former uses [`DiffableStr::to_string_lossy`], the latter uses
+//! [`DiffableStr::as_bytes`] for each line.
+#[cfg(feature = "text")]
+use std::{fmt, io};
+
+use crate::iter::AllChangesIter;
+use crate::text::{DiffableStr, TextDiff};
+use crate::types::{Algorithm, DiffOp};
+
+struct MissingNewlineHint(bool);
+
+impl fmt::Display for MissingNewlineHint {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ if self.0 {
+ write!(f, "\n\\ No newline at end of file")?;
+ }
+ Ok(())
+ }
+}
+
+#[derive(Copy, Clone, Debug)]
+struct UnifiedDiffHunkRange(usize, usize);
+
+impl UnifiedDiffHunkRange {
+ fn start(&self) -> usize {
+ self.0
+ }
+
+ fn end(&self) -> usize {
+ self.1
+ }
+}
+
+impl fmt::Display for UnifiedDiffHunkRange {
+ fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+ let mut beginning = self.start() + 1;
+ let len = self.end() - self.start();
+ if len == 1 {
+ write!(f, "{}", beginning)
+ } else {
+ if len == 0 {
+ // empty ranges begin at line just before the range
+ beginning -= 1;
+ }
+ write!(f, "{},{}", beginning, len)
+ }
+ }
+}
+
+/// Unified diff hunk header formatter.
+pub struct UnifiedHunkHeader {
+ old_range: UnifiedDiffHunkRange,
+ new_range: UnifiedDiffHunkRange,
+}
+
+impl UnifiedHunkHeader {
+ /// Creates a hunk header from a (non empty) slice of diff ops.
+ pub fn new(ops: &[DiffOp]) -> UnifiedHunkHeader {
+ let first = ops[0];
+ let last = ops[ops.len() - 1];
+ let old_start = first.old_range().start;
+ let new_start = first.new_range().start;
+ let old_end = last.old_range().end;
+ let new_end = last.new_range().end;
+ UnifiedHunkHeader {
+ old_range: UnifiedDiffHunkRange(old_start, old_end),
+ new_range: UnifiedDiffHunkRange(new_start, new_end),
+ }
+ }
+}
+
+impl fmt::Display for UnifiedHunkHeader {
+ fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+ write!(f, "@@ -{} +{} @@", &self.old_range, &self.new_range)
+ }
+}
+
+/// Unified diff formatter.
+///
+/// ```rust
+/// use similar::TextDiff;
+/// # let old_text = "";
+/// # let new_text = "";
+/// let text_diff = TextDiff::from_lines(old_text, new_text);
+/// print!("{}", text_diff
+/// .unified_diff()
+/// .context_radius(10)
+/// .header("old_file", "new_file"));
+/// ```
+///
+/// ## Unicode vs Bytes
+///
+/// The [`UnifiedDiff`] type supports both unicode and byte diffs for all
+/// types compatible with [`DiffableStr`]. You can pick between the two
+/// versions by using [`UnifiedDiff.to_string`] or [`UnifiedDiff.to_writer`].
+/// The former uses [`DiffableStr::to_string_lossy`], the latter uses
+/// [`DiffableStr::as_bytes`] for each line.
+pub struct UnifiedDiff<'diff, 'old, 'new, 'bufs, T: DiffableStr + ?Sized> {
+ diff: &'diff TextDiff<'old, 'new, 'bufs, T>,
+ context_radius: usize,
+ missing_newline_hint: bool,
+ header: Option<(String, String)>,
+}
+
+impl<'diff, 'old, 'new, 'bufs, T: DiffableStr + ?Sized> UnifiedDiff<'diff, 'old, 'new, 'bufs, T> {
+ /// Creates a formatter from a text diff object.
+ pub fn from_text_diff(diff: &'diff TextDiff<'old, 'new, 'bufs, T>) -> Self {
+ UnifiedDiff {
+ diff,
+ context_radius: 3,
+ missing_newline_hint: true,
+ header: None,
+ }
+ }
+
+ /// Changes the context radius.
+ ///
+ /// The context radius is the number of lines between changes that should
+ /// be emitted. This defaults to `3`.
+ pub fn context_radius(&mut self, n: usize) -> &mut Self {
+ self.context_radius = n;
+ self
+ }
+
+ /// Sets a header to the diff.
+ ///
+ /// `a` and `b` are the file names that are added to the top of the unified
+ /// file format. The names are accepted verbatim which lets you encode
+ /// a timestamp into it when separated by a tab (`\t`). For more information
+ /// see [the unified diff format specification](https://pubs.opengroup.org/onlinepubs/9699919799/utilities/diff.html#tag_20_34_10_07)
+ pub fn header(&mut self, a: &str, b: &str) -> &mut Self {
+ self.header = Some((a.to_string(), b.to_string()));
+ self
+ }
+
+ /// Controls the missing newline hint.
+ ///
+ /// By default a special `\ No newline at end of file` marker is added to
+ /// the output when a file is not terminated with a final newline. This can
+ /// be disabled with this flag.
+ pub fn missing_newline_hint(&mut self, yes: bool) -> &mut Self {
+ self.missing_newline_hint = yes;
+ self
+ }
+
+ /// Iterates over all hunks as configured.
+ pub fn iter_hunks(&self) -> impl Iterator<Item = UnifiedDiffHunk<'diff, 'old, 'new, 'bufs, T>> {
+ let diff = self.diff;
+ let missing_newline_hint = self.missing_newline_hint;
+ self.diff
+ .grouped_ops(self.context_radius)
+ .into_iter()
+ .filter(|ops| !ops.is_empty())
+ .map(move |ops| UnifiedDiffHunk::new(ops, diff, missing_newline_hint))
+ }
+
+ /// Write the unified diff as bytes to the output stream.
+ pub fn to_writer<W: io::Write>(&self, mut w: W) -> Result<(), io::Error>
+ where
+ 'diff: 'old + 'new + 'bufs,
+ {
+ let mut header = self.header.as_ref();
+ for hunk in self.iter_hunks() {
+ if let Some((old_file, new_file)) = header.take() {
+ writeln!(w, "--- {}", old_file)?;
+ writeln!(w, "+++ {}", new_file)?;
+ }
+ write!(w, "{}", hunk)?;
+ }
+ Ok(())
+ }
+
+ fn header_opt(&mut self, header: Option<(&str, &str)>) -> &mut Self {
+ if let Some((a, b)) = header {
+ self.header(a, b);
+ }
+ self
+ }
+}
+
+/// Unified diff hunk formatter.
+///
+/// The `Display` this renders out a single unified diff's hunk.
+pub struct UnifiedDiffHunk<'diff, 'old, 'new, 'bufs, T: DiffableStr + ?Sized> {
+ diff: &'diff TextDiff<'old, 'new, 'bufs, T>,
+ ops: Vec<DiffOp>,
+ missing_newline_hint: bool,
+}
+
+impl<'diff, 'old, 'new, 'bufs, T: DiffableStr + ?Sized>
+ UnifiedDiffHunk<'diff, 'old, 'new, 'bufs, T>
+{
+ /// Creates a new hunk for some operations.
+ pub fn new(
+ ops: Vec<DiffOp>,
+ diff: &'diff TextDiff<'old, 'new, 'bufs, T>,
+ missing_newline_hint: bool,
+ ) -> UnifiedDiffHunk<'diff, 'old, 'new, 'bufs, T> {
+ UnifiedDiffHunk {
+ diff,
+ ops,
+ missing_newline_hint,
+ }
+ }
+
+ /// Returns the header for the hunk.
+ pub fn header(&self) -> UnifiedHunkHeader {
+ UnifiedHunkHeader::new(&self.ops)
+ }
+
+ /// Returns all operations in the hunk.
+ pub fn ops(&self) -> &[DiffOp] {
+ &self.ops
+ }
+
+ /// Returns the value of the `missing_newline_hint` flag.
+ pub fn missing_newline_hint(&self) -> bool {
+ self.missing_newline_hint
+ }
+
+ /// Iterates over all changes in a hunk.
+ pub fn iter_changes<'x, 'slf>(&'slf self) -> AllChangesIter<'slf, 'x, T>
+ where
+ 'x: 'slf + 'old + 'new,
+ 'old: 'x,
+ 'new: 'x,
+ {
+ AllChangesIter::new(self.diff.old_slices(), self.diff.new_slices(), self.ops())
+ }
+
+ /// Write the hunk as bytes to the output stream.
+ pub fn to_writer<W: io::Write>(&self, mut w: W) -> Result<(), io::Error>
+ where
+ 'diff: 'old + 'new + 'bufs,
+ {
+ for (idx, change) in self.iter_changes().enumerate() {
+ if idx == 0 {
+ writeln!(w, "{}", self.header())?;
+ }
+ write!(w, "{}", change.tag())?;
+ w.write_all(change.value().as_bytes())?;
+ if !self.diff.newline_terminated() {
+ writeln!(w)?;
+ }
+ if self.diff.newline_terminated() && change.missing_newline() {
+ writeln!(w, "{}", MissingNewlineHint(self.missing_newline_hint))?;
+ }
+ }
+ Ok(())
+ }
+}
+
+impl<'diff, 'old, 'new, 'bufs, T: DiffableStr + ?Sized> fmt::Display
+ for UnifiedDiffHunk<'diff, 'old, 'new, 'bufs, T>
+where
+ 'diff: 'old + 'new + 'bufs,
+{
+ fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+ for (idx, change) in self.iter_changes().enumerate() {
+ if idx == 0 {
+ writeln!(f, "{}", self.header())?;
+ }
+ write!(f, "{}{}", change.tag(), change.to_string_lossy())?;
+ if !self.diff.newline_terminated() {
+ writeln!(f)?;
+ }
+ if self.diff.newline_terminated() && change.missing_newline() {
+ writeln!(f, "{}", MissingNewlineHint(self.missing_newline_hint))?;
+ }
+ }
+ Ok(())
+ }
+}
+
+impl<'diff, 'old, 'new, 'bufs, T: DiffableStr + ?Sized> fmt::Display
+ for UnifiedDiff<'diff, 'old, 'new, 'bufs, T>
+where
+ 'diff: 'old + 'new + 'bufs,
+{
+ fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+ let mut header = self.header.as_ref();
+ for hunk in self.iter_hunks() {
+ if let Some((old_file, new_file)) = header.take() {
+ writeln!(f, "--- {}", old_file)?;
+ writeln!(f, "+++ {}", new_file)?;
+ }
+ write!(f, "{}", hunk)?;
+ }
+ Ok(())
+ }
+}
+
+/// Quick way to get a unified diff as string.
+///
+/// `n` configures [`UnifiedDiff::context_radius`] and
+/// `header` configures [`UnifiedDiff::header`] when not `None`.
+pub fn unified_diff<'old, 'new>(
+ alg: Algorithm,
+ old: &'old str,
+ new: &'new str,
+ n: usize,
+ header: Option<(&str, &str)>,
+) -> String {
+ TextDiff::configure()
+ .algorithm(alg)
+ .diff_lines(old, new)
+ .unified_diff()
+ .context_radius(n)
+ .header_opt(header)
+ .to_string()
+}
+
+#[test]
+fn test_unified_diff() {
+ let diff = TextDiff::from_lines(
+ "a\nb\nc\nd\ne\nf\ng\nh\ni\nj\nk\nl\nm\nn\no\np\nq\nr\ns\nt\nu\nv\nw\nx\ny\nz\nA\nB\nC\nD\nE\nF\nG\nH\nI\nJ\nK\nL\nM\nN\nO\nP\nQ\nR\nS\nT\nU\nV\nW\nX\nY\nZ",
+ "a\nb\nc\nd\ne\nf\ng\nh\ni\nj\nk\nl\nm\nn\no\np\nq\nr\nS\nt\nu\nv\nw\nx\ny\nz\nA\nB\nC\nD\nE\nF\nG\nH\nI\nJ\nK\nL\nM\nN\no\nP\nQ\nR\nS\nT\nU\nV\nW\nX\nY\nZ",
+ );
+ insta::assert_snapshot!(&diff.unified_diff().header("a.txt", "b.txt").to_string());
+}
+#[test]
+fn test_empty_unified_diff() {
+ let diff = TextDiff::from_lines("abc", "abc");
+ assert_eq!(diff.unified_diff().header("a.txt", "b.txt").to_string(), "");
+}
+
+#[test]
+fn test_unified_diff_newline_hint() {
+ let diff = TextDiff::from_lines("a\n", "b");
+ insta::assert_snapshot!(&diff.unified_diff().header("a.txt", "b.txt").to_string());
+ insta::assert_snapshot!(&diff
+ .unified_diff()
+ .missing_newline_hint(false)
+ .header("a.txt", "b.txt")
+ .to_string());
+}