1 files changed, 110 insertions, 0 deletions
diff --git a/vendor/gix-config/src/value/normalize.rs b/vendor/gix-config/src/value/normalize.rs
new file mode 100644
index 000000000..1f16b05d8
--- /dev/null
+++ b/vendor/gix-config/src/value/normalize.rs
@@ -0,0 +1,110 @@
+use std::borrow::Cow;
+
+use bstr::{BStr, BString, ByteSlice};
+
+/// Removes quotes, if any, from the provided inputs, and transforms
+/// the 3 escape sequences `\n`, `\t` and `\b` into newline and tab
+/// respectively, while `\b` will remove the previous character.
+///
+/// It assumes the input contains a even number of unescaped quotes,
+/// and will unescape escaped quotes and everything else (even though the latter
+/// would have been rejected in the parsing stage).
+///
+/// The return values should be safe for value interpretation.
+///
+/// This has optimizations for fully-quoted values, where the returned value
+/// will be a borrowed reference if the only mutation necessary is to unquote
+/// the value.
+///
+/// This is the function used to normalize raw values from higher level
+/// abstractions. Generally speaking these
+/// high level abstractions will handle normalization for you, and you do not
+/// need to call this yourself. However, if you're directly handling events
+/// from the parser, you may want to use this to help with value interpretation.
+///
+/// Generally speaking, you'll want to use one of the variants of this function,
+/// such as [`normalize_bstr`] or [`normalize_bstring`].
+///
+/// # Examples
+///
+/// Values don't need modification are returned borrowed, without allocation.
+///
+/// ```
+/// # use std::borrow::Cow;
+/// # use bstr::ByteSlice;
+/// # use gix_config::value::normalize_bstr;
+/// assert!(matches!(normalize_bstr("hello world"), Cow::Borrowed(_)));
+/// ```
+///
+/// Internally quoted values are turned into owned variant with quotes removed.
+///
+/// ```
+/// # use std::borrow::Cow;
+/// # use bstr::{BStr, BString};
+/// # use gix_config::value::{normalize_bstr};
+/// assert_eq!(normalize_bstr("hello \"world\""), Cow::<BStr>::Owned(BString::from("hello world")));
+/// ```
+///
+/// Escaped quotes are unescaped.
+///
+/// ```
+/// # use std::borrow::Cow;
+/// # use bstr::{BStr, BString};
+/// # use gix_config::value::normalize_bstr;
+/// assert_eq!(normalize_bstr(r#"hello "world\"""#), Cow::<BStr>::Owned(BString::from(r#"hello world""#)));
+/// ```
+#[must_use]
+pub fn normalize(input: Cow<'_, BStr>) -> Cow<'_, BStr> {
+    if input.as_ref() == "\"\"" {
+        return Cow::Borrowed("".into());
+    }
+
+    let size = input.len();
+    if size >= 3 && input[0] == b'"' && input[size - 1] == b'"' && input[size - 2] != b'\\' {
+        match input {
+            Cow::Borrowed(input) => return normalize_bstr(&input[1..size - 1]),
+            Cow::Owned(mut input) => {
+                input.pop();
+                input.remove(0);
+                return normalize_bstring(input);
+            }
+        }
+    }
+
+    if input.find_byteset(b"\\\"").is_none() {
+        return input;
+    }
+
+    let mut out: BString = Vec::with_capacity(input.len()).into();
+    let mut bytes = input.iter().copied();
+    while let Some(c) = bytes.next() {
+        match c {
+            b'\\' => match bytes.next() {
+                Some(b'n') => out.push(b'\n'),
+                Some(b't') => out.push(b'\t'),
+                Some(b'b') => {
+                    out.pop();
+                }
+                Some(c) => {
+                    out.push(c);
+                }
+                None => break,
+            },
+            b'"' => {}
+            _ => out.push(c),
+        }
+    }
+    Cow::Owned(out)
+}
+
+/// `&[u8]` variant of [`normalize`].
+#[must_use]
+pub fn normalize_bstr<'a>(input: impl Into<&'a BStr>) -> Cow<'a, BStr> {
+    normalize(Cow::Borrowed(input.into()))
+}
+
+/// `Vec[u8]` variant of [`normalize`].
+#[must_use]
+pub fn normalize_bstring(input: impl Into<BString>) -> Cow<'static, BStr> {
+    normalize(Cow::Owned(input.into()))
+}