1 files changed, 251 insertions, 0 deletions
diff --git a/vendor/time-macros/src/format_description/ast.rs b/vendor/time-macros/src/format_description/ast.rs
new file mode 100644
index 000000000..497c8965d
--- /dev/null
+++ b/vendor/time-macros/src/format_description/ast.rs
@@ -0,0 +1,251 @@
+use std::boxed::Box;
+use std::iter;
+
+use super::{lexer, unused, Error, Location, Spanned, SpannedValue, Unused};
+
+pub(super) enum Item<'a> {
+    Literal(Spanned<&'a [u8]>),
+    EscapedBracket {
+        _first: Unused<Location>,
+        _second: Unused<Location>,
+    },
+    Component {
+        _opening_bracket: Unused<Location>,
+        _leading_whitespace: Unused<Option<Spanned<&'a [u8]>>>,
+        name: Spanned<&'a [u8]>,
+        modifiers: Box<[Modifier<'a>]>,
+        _trailing_whitespace: Unused<Option<Spanned<&'a [u8]>>>,
+        _closing_bracket: Unused<Location>,
+    },
+    Optional {
+        opening_bracket: Location,
+        _leading_whitespace: Unused<Option<Spanned<&'a [u8]>>>,
+        _optional_kw: Unused<Spanned<&'a [u8]>>,
+        _whitespace: Unused<Spanned<&'a [u8]>>,
+        nested_format_description: NestedFormatDescription<'a>,
+        closing_bracket: Location,
+    },
+    First {
+        opening_bracket: Location,
+        _leading_whitespace: Unused<Option<Spanned<&'a [u8]>>>,
+        _first_kw: Unused<Spanned<&'a [u8]>>,
+        _whitespace: Unused<Spanned<&'a [u8]>>,
+        nested_format_descriptions: Box<[NestedFormatDescription<'a>]>,
+        closing_bracket: Location,
+    },
+}
+
+pub(super) struct NestedFormatDescription<'a> {
+    pub(super) _opening_bracket: Unused<Location>,
+    pub(super) items: Box<[Item<'a>]>,
+    pub(super) _closing_bracket: Unused<Location>,
+    pub(super) _trailing_whitespace: Unused<Option<Spanned<&'a [u8]>>>,
+}
+
+pub(super) struct Modifier<'a> {
+    pub(super) _leading_whitespace: Unused<Spanned<&'a [u8]>>,
+    pub(super) key: Spanned<&'a [u8]>,
+    pub(super) _colon: Unused<Location>,
+    pub(super) value: Spanned<&'a [u8]>,
+}
+
+pub(super) fn parse<
+    'item: 'iter,
+    'iter,
+    I: Iterator<Item = Result<lexer::Token<'item>, Error>>,
+    const VERSION: u8,
+>(
+    tokens: &'iter mut lexer::Lexed<I>,
+) -> impl Iterator<Item = Result<Item<'item>, Error>> + 'iter {
+    assert!(version!(1..=2));
+    parse_inner::<_, false, VERSION>(tokens)
+}
+
+fn parse_inner<
+    'item,
+    I: Iterator<Item = Result<lexer::Token<'item>, Error>>,
+    const NESTED: bool,
+    const VERSION: u8,
+>(
+    tokens: &mut lexer::Lexed<I>,
+) -> impl Iterator<Item = Result<Item<'item>, Error>> + '_ {
+    iter::from_fn(move || {
+        if NESTED && tokens.peek_closing_bracket().is_some() {
+            return None;
+        }
+
+        let next = match tokens.next()? {
+            Ok(token) => token,
+            Err(err) => return Some(Err(err)),
+        };
+
+        Some(match next {
+            lexer::Token::Literal(Spanned { value: _, span: _ }) if NESTED => {
+                bug!("literal should not be present in nested description")
+            }
+            lexer::Token::Literal(value) => Ok(Item::Literal(value)),
+            lexer::Token::Bracket {
+                kind: lexer::BracketKind::Opening,
+                location,
+            } => {
+                if version!(..=1) {
+                    if let Some(second_location) = tokens.next_if_opening_bracket() {
+                        Ok(Item::EscapedBracket {
+                            _first: unused(location),
+                            _second: unused(second_location),
+                        })
+                    } else {
+                        parse_component::<_, VERSION>(location, tokens)
+                    }
+                } else {
+                    parse_component::<_, VERSION>(location, tokens)
+                }
+            }
+            lexer::Token::Bracket {
+                kind: lexer::BracketKind::Closing,
+                location: _,
+            } if NESTED => {
+                bug!("closing bracket should be caught by the `if` statement")
+            }
+            lexer::Token::Bracket {
+                kind: lexer::BracketKind::Closing,
+                location: _,
+            } => {
+                bug!("closing bracket should have been consumed by `parse_component`")
+            }
+            lexer::Token::ComponentPart { kind: _, value } if NESTED => Ok(Item::Literal(value)),
+            lexer::Token::ComponentPart { kind: _, value: _ } => {
+                bug!("component part should have been consumed by `parse_component`")
+            }
+        })
+    })
+}
+
+fn parse_component<'a, I: Iterator<Item = Result<lexer::Token<'a>, Error>>, const VERSION: u8>(
+    opening_bracket: Location,
+    tokens: &mut lexer::Lexed<I>,
+) -> Result<Item<'a>, Error> {
+    let leading_whitespace = tokens.next_if_whitespace();
+
+    guard!(let Some(name) = tokens.next_if_not_whitespace() else {
+        let span = match leading_whitespace {
+            Some(Spanned { value: _, span }) => span,
+            None => opening_bracket.to(opening_bracket),
+        };
+        return Err(span.error("expected component name"));
+    });
+
+    if *name == b"optional" {
+        guard!(let Some(whitespace) = tokens.next_if_whitespace() else {
+            return Err(name.span.error("expected whitespace after `optional`"));
+        });
+
+        let nested = parse_nested::<_, VERSION>(whitespace.span.end, tokens)?;
+
+        guard!(let Some(closing_bracket) = tokens.next_if_closing_bracket() else {
+            return Err(opening_bracket.error("unclosed bracket"));
+        });
+
+        return Ok(Item::Optional {
+            opening_bracket,
+            _leading_whitespace: unused(leading_whitespace),
+            _optional_kw: unused(name),
+            _whitespace: unused(whitespace),
+            nested_format_description: nested,
+            closing_bracket,
+        });
+    }
+
+    if *name == b"first" {
+        guard!(let Some(whitespace) = tokens.next_if_whitespace() else {
+            return Err(name.span.error("expected whitespace after `first`"));
+        });
+
+        let mut nested_format_descriptions = Vec::new();
+        while let Ok(description) = parse_nested::<_, VERSION>(whitespace.span.end, tokens) {
+            nested_format_descriptions.push(description);
+        }
+
+        guard!(let Some(closing_bracket) = tokens.next_if_closing_bracket() else {
+            return Err(opening_bracket.error("unclosed bracket"));
+        });
+
+        return Ok(Item::First {
+            opening_bracket,
+            _leading_whitespace: unused(leading_whitespace),
+            _first_kw: unused(name),
+            _whitespace: unused(whitespace),
+            nested_format_descriptions: nested_format_descriptions.into_boxed_slice(),
+            closing_bracket,
+        });
+    }
+
+    let mut modifiers = Vec::new();
+    let trailing_whitespace = loop {
+        guard!(let Some(whitespace) = tokens.next_if_whitespace() else { break None });
+
+        if let Some(location) = tokens.next_if_opening_bracket() {
+            return Err(location
+                .to(location)
+                .error("modifier must be of the form `key:value`"));
+        }
+
+        guard!(let Some(Spanned { value, span }) = tokens.next_if_not_whitespace() else {
+            break Some(whitespace);
+        });
+
+        guard!(let Some(colon_index) = value.iter().position(|&b| b == b':') else {
+            return Err(span.error("modifier must be of the form `key:value`"));
+        });
+        let key = &value[..colon_index];
+        let value = &value[colon_index + 1..];
+
+        if key.is_empty() {
+            return Err(span.shrink_to_start().error("expected modifier key"));
+        }
+        if value.is_empty() {
+            return Err(span.shrink_to_end().error("expected modifier value"));
+        }
+
+        modifiers.push(Modifier {
+            _leading_whitespace: unused(whitespace),
+            key: key.spanned(span.shrink_to_before(colon_index as _)),
+            _colon: unused(span.start.offset(colon_index as _)),
+            value: value.spanned(span.shrink_to_after(colon_index as _)),
+        });
+    };
+
+    guard!(let Some(closing_bracket) = tokens.next_if_closing_bracket() else {
+        return Err(opening_bracket.error("unclosed bracket"));
+    });
+
+    Ok(Item::Component {
+        _opening_bracket: unused(opening_bracket),
+        _leading_whitespace: unused(leading_whitespace),
+        name,
+        modifiers: modifiers.into_boxed_slice(),
+        _trailing_whitespace: unused(trailing_whitespace),
+        _closing_bracket: unused(closing_bracket),
+    })
+}
+
+fn parse_nested<'a, I: Iterator<Item = Result<lexer::Token<'a>, Error>>, const VERSION: u8>(
+    last_location: Location,
+    tokens: &mut lexer::Lexed<I>,
+) -> Result<NestedFormatDescription<'a>, Error> {
+    guard!(let Some(opening_bracket) = tokens.next_if_opening_bracket() else {
+        return Err(last_location.error("expected opening bracket"));
+    });
+    let items = parse_inner::<_, true, VERSION>(tokens).collect::<Result<_, _>>()?;
+    guard!(let Some(closing_bracket) = tokens.next_if_closing_bracket() else {
+        return Err(opening_bracket.error("unclosed bracket"));
+    });
+    let trailing_whitespace = tokens.next_if_whitespace();
+
+    Ok(NestedFormatDescription {
+        _opening_bracket: unused(opening_bracket),
+        items,
+        _closing_bracket: unused(closing_bracket),
+        _trailing_whitespace: unused(trailing_whitespace),
+    })
+}