Make syntax not depend on parse 📩

This would make it possible to split them into two separate crates.

4 files changed, 61 insertions, 127 deletions

diff --git a/src/syntax/lines.rs b/src/syntax/lines.rs
deleted file mode 100644
index 6ea223c4..00000000
--- a/src/syntax/lines.rs
+++ /dev/null
@@ -1,108 +0,0 @@
-//! Conversion of byte positions to line/column locations.
-
-use std::fmt::{self, Debug, Display, Formatter};
-
-use super::Pos;
-use crate::parse::{is_newline_char, Scanner};
-
-/// Enables conversion of byte position to locations.
-pub struct LineMap<'s> {
-    src: &'s str,
-    line_starts: Vec<Pos>,
-}
-
-impl<'s> LineMap<'s> {
-    /// Create a new line map for a source string.
-    pub fn new(src: &'s str) -> Self {
-        let mut line_starts = vec![Pos::ZERO];
-        let mut s = Scanner::new(src);
-
-        while let Some(c) = s.eat_merging_crlf() {
-            if is_newline_char(c) {
-                line_starts.push(s.index().into());
-            }
-        }
-
-        Self { src, line_starts }
-    }
-
-    /// Convert a byte position to a location.
-    ///
-    /// # Panics
-    /// This panics if the position is out of bounds.
-    pub fn location(&self, pos: Pos) -> Location {
-        let line_index = match self.line_starts.binary_search(&pos) {
-            Ok(i) => i,
-            Err(i) => i - 1,
-        };
-
-        let line_start = self.line_starts[line_index];
-        let head = &self.src[line_start.to_usize() .. pos.to_usize()];
-        let column_index = head.chars().count();
-
-        Location {
-            line: 1 + line_index as u32,
-            column: 1 + column_index as u32,
-        }
-    }
-}
-
-/// One-indexed line-column position in source code.
-#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
-#[cfg_attr(feature = "serialize", derive(serde::Serialize))]
-pub struct Location {
-    /// The one-indexed line.
-    pub line: u32,
-    /// The one-indexed column.
-    pub column: u32,
-}
-
-impl Location {
-    /// Create a new location from line and column.
-    pub fn new(line: u32, column: u32) -> Self {
-        Self { line, column }
-    }
-}
-
-impl Debug for Location {
-    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
-        Display::fmt(self, f)
-    }
-}
-
-impl Display for Location {
-    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
-        write!(f, "{}:{}", self.line, self.column)
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    const TEST: &str = "äbcde\nf💛g\r\nhi\rjkl";
-
-    #[test]
-    fn test_line_map_new() {
-        let map = LineMap::new(TEST);
-        assert_eq!(map.line_starts, vec![Pos(0), Pos(7), Pos(15), Pos(18)]);
-    }
-
-    #[test]
-    fn test_line_map_location() {
-        let map = LineMap::new(TEST);
-        assert_eq!(map.location(Pos(0)), Location::new(1, 1));
-        assert_eq!(map.location(Pos(2)), Location::new(1, 2));
-        assert_eq!(map.location(Pos(6)), Location::new(1, 6));
-        assert_eq!(map.location(Pos(7)), Location::new(2, 1));
-        assert_eq!(map.location(Pos(8)), Location::new(2, 2));
-        assert_eq!(map.location(Pos(12)), Location::new(2, 3));
-        assert_eq!(map.location(Pos(21)), Location::new(4, 4));
-    }
-
-    #[test]
-    #[should_panic]
-    fn test_line_map_panics_out_of_bounds() {
-        LineMap::new(TEST).location(Pos(22));
-    }
-}
diff --git a/src/syntax/mod.rs b/src/syntax/mod.rs
index f442ba9e..fe887c2f 100644
--- a/src/syntax/mod.rs
+++ b/src/syntax/mod.rs
@@ -1,11 +1,9 @@
 //! Syntax types.
 
-mod lines;
 mod span;
 mod token;
 mod tree;
 
-pub use lines::*;
 pub use span::*;
 pub use token::*;
 pub use tree::*;
diff --git a/src/syntax/span.rs b/src/syntax/span.rs
index d803eeeb..eb029479 100644
--- a/src/syntax/span.rs
+++ b/src/syntax/span.rs
@@ -1,6 +1,6 @@
 //! Mapping of values to the locations they originate from in source code.
 
-use std::fmt::{self, Debug, Formatter};
+use std::fmt::{self, Debug, Display, Formatter};
 
 #[cfg(test)]
 use std::cell::Cell;
@@ -168,7 +168,7 @@ impl Debug for Span {
     }
 }
 
-/// A byte position.
+/// A byte position in source code.
 #[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
 #[cfg_attr(feature = "serialize", derive(serde::Serialize))]
 pub struct Pos(pub u32);
@@ -203,6 +203,35 @@ impl Offset for Pos {
 
 impl Debug for Pos {
     fn fmt(&self, f: &mut Formatter) -> fmt::Result {
-        self.0.fmt(f)
+        Debug::fmt(&self.0, f)
+    }
+}
+
+/// A one-indexed line-column position in source code.
+#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
+#[cfg_attr(feature = "serialize", derive(serde::Serialize))]
+pub struct Location {
+    /// The one-indexed line.
+    pub line: u32,
+    /// The one-indexed column.
+    pub column: u32,
+}
+
+impl Location {
+    /// Create a new location from line and column.
+    pub fn new(line: u32, column: u32) -> Self {
+        Self { line, column }
+    }
+}
+
+impl Debug for Location {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        Display::fmt(self, f)
+    }
+}
+
+impl Display for Location {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        write!(f, "{}:{}", self.line, self.column)
     }
 }
diff --git a/src/syntax/tree.rs b/src/syntax/tree.rs
index bfbb3706..ee53d476 100644
--- a/src/syntax/tree.rs
+++ b/src/syntax/tree.rs
@@ -1,6 +1,7 @@
 //! The syntax tree.
 
 use std::fmt::{self, Debug, Formatter};
+use std::ops::Deref;
 
 use unicode_xid::UnicodeXID;
 
@@ -234,7 +235,7 @@ pub struct Ident(pub String);
 impl Ident {
     /// Create a new identifier from a string checking that it is a valid.
     pub fn new(ident: impl AsRef<str> + Into<String>) -> Option<Self> {
-        if Self::is_ident(ident.as_ref()) {
+        if is_ident(ident.as_ref()) {
             Some(Self(ident.into()))
         } else {
             None
@@ -243,21 +244,21 @@ impl Ident {
 
     /// Return a reference to the underlying string.
     pub fn as_str(&self) -> &str {
-        self.0.as_str()
+        self
     }
+}
 
-    /// Whether the string is a valid identifier.
-    pub fn is_ident(string: &str) -> bool {
-        fn is_ok(c: char) -> bool {
-            c == '-' || c == '_'
-        }
+impl AsRef<str> for Ident {
+    fn as_ref(&self) -> &str {
+        self
+    }
+}
 
-        let mut chars = string.chars();
-        if matches!(chars.next(), Some(c) if c.is_xid_start() || is_ok(c)) {
-            chars.all(|c| c.is_xid_continue() || is_ok(c))
-        } else {
-            false
-        }
+impl Deref for Ident {
+    type Target = str;
+
+    fn deref(&self) -> &Self::Target {
+        self.0.as_str()
     }
 }
 
@@ -267,6 +268,20 @@ impl Debug for Ident {
     }
 }
 
+/// Whether the string is a valid identifier.
+pub fn is_ident(string: &str) -> bool {
+    fn is_ok(c: char) -> bool {
+        c == '-' || c == '_'
+    }
+
+    let mut chars = string.chars();
+    if matches!(chars.next(), Some(c) if c.is_xid_start() || is_ok(c)) {
+        chars.all(|c| c.is_xid_continue() || is_ok(c))
+    } else {
+        false
+    }
+}
+
 /// A table of expressions.
 ///
 /// # Example
@@ -307,7 +322,7 @@ pub struct CallExpr {
 impl CallExpr {
     /// Evaluate the call expression to a value.
     pub async fn eval(&self, ctx: &LayoutContext<'_>, f: &mut Feedback) -> Value {
-        let name = self.name.v.as_str();
+        let name = &self.name.v;
         let span = self.name.span;
         let args = self.args.eval(ctx, f).await;