refactor: use std::fmt::Write for printer output

derive/src/to_css.rs

@@ -121,7 +121,10 @@ fn derive_enum(data: &DataEnum, opts: &CssOptions) -> TokenStream2 {
         Fields::Unit => {
           let s = Literal::string(&variant.ident.to_string().to_case(opts.case));
           quote! {
-            Self::#name => dest.write_str(#s)
+            Self::#name => {
+              dest.write_str(#s)?;
+              Ok(())
+            }
           }
         }
         Fields::Named(_) => {

examples/custom_at_rule.rs

@@ -1,4 +1,4 @@
-use std::{collections::HashMap, convert::Infallible};
+use std::{collections::HashMap, convert::Infallible, fmt::Write};
 
 use cssparser::*;
 use rspack_lightningcss::{
@@ -295,7 +295,8 @@ impl ToCss for AtRule {
           TailwindDirective::Utilities => "TAILWIND UTILITIES HERE",
           TailwindDirective::Variants => "TAILWIND VARIANTS HERE",
         };
-        dest.write_str(directive)
+        dest.write_str(directive)?;
+        Ok(())
       }
       AtRule::Apply(_) => Ok(()),
     }

napi/src/at_rule_parser.rs

@@ -1,4 +1,4 @@
-use std::collections::HashMap;
+use std::{collections::HashMap, fmt::Write};
 
 use cssparser::*;
 use rspack_lightningcss::{

src/declaration.rs

@@ -1,6 +1,7 @@
 //! CSS declarations.
 
 use std::borrow::Cow;
+use std::fmt::Write;
 use std::ops::Range;
 
 use crate::context::{DeclarationContext, PropertyHandlerContext};
@@ -170,7 +171,8 @@ impl<'i> DeclarationBlock<'i> {
 
     dest.dedent();
     dest.newline()?;
-    dest.write_char('}')
+    dest.write_char('}')?;
+    Ok(())
   }
 
   pub(crate) fn has_printable_declarations(&self) -> bool {

src/macros.rs

@@ -84,7 +84,8 @@ macro_rules! enum_property {
 
     impl ToCss for $name {
       fn to_css<W>(&self, dest: &mut Printer<W>) -> Result<(), PrinterError> where W: std::fmt::Write {
-        dest.write_str(self.as_str())
+        dest.write_str(self.as_str())?;
+        Ok(())
       }
     }
   };

src/media_query.rs

@@ -24,6 +24,7 @@ use cssparser::*;
 use rspack_lightningcss_static_self::IntoOwned;
 use std::borrow::Cow;
 use std::collections::{HashMap, HashSet};
+use std::fmt::Write;
 
 #[cfg(feature = "serde")]
 use crate::serialization::ValueWrapper;
@@ -1216,7 +1217,9 @@ impl<'i, FeatureId: FeatureToCss> ToCss for QueryFeature<'i, FeatureId> {
       }
     }
 
-    dest.write_char(')')
+    dest.write_char(')')?;
+
+    Ok(())
   }
 }
 
@@ -1508,7 +1511,8 @@ impl FeatureToCss for MediaFeatureId {
       MediaFeatureId::WebKitDevicePixelRatio => {
         dest.write_str("-webkit-")?;
         dest.write_str(prefix)?;
-        dest.write_str("device-pixel-ratio")
+        dest.write_str("device-pixel-ratio")?;
+        Ok(())
       }
       _ => {
         dest.write_str(prefix)?;
@@ -1704,9 +1708,11 @@ impl<'i> ToCss for MediaFeatureValue<'i> {
       MediaFeatureValue::Integer(num) => num.to_css(dest),
       MediaFeatureValue::Boolean(b) => {
         if *b {
-          dest.write_char('1')
+          dest.write_char('1')?;
+          Ok(())
         } else {
-          dest.write_char('0')
+          dest.write_char('0')?;
+          Ok(())
         }
       }
       MediaFeatureValue::Resolution(res) => res.to_css(dest),

src/printer.rs

@@ -10,6 +10,7 @@ use crate::vendor_prefix::VendorPrefix;
 use cssparser::{serialize_identifier, serialize_name};
 #[cfg(feature = "sourcemap")]
 use parcel_sourcemap::{OriginalLocation, SourceMap};
+use std::fmt::Write;
 
 /// Options that control how CSS is serialized to a string.
 #[derive(Default)]
@@ -140,47 +141,6 @@ impl<'a, 'c, W: std::fmt::Write + Sized> Printer<'a, 'c, W> {
     }
   }
 
-  /// Writes a raw string to the underlying destination.
-  ///
-  /// NOTE: Is is assumed that the string does not contain any newline characters.
-  /// If such a string is written, it will break source maps.
-  pub fn write_str(&mut self, s: &str) -> Result<(), PrinterError> {
-    self.col += s.len() as u32;
-    self.dest.write_str(s)?;
-    Ok(())
-  }
-
-  /// Writes a raw string which may contain newlines to the underlying destination.
-  pub fn write_str_with_newlines(&mut self, s: &str) -> Result<(), PrinterError> {
-    let mut last_line_start: usize = 0;
-
-    for (idx, n) in s.char_indices() {
-      if n == '\n' {
-        self.line += 1;
-        self.col = 0;
-
-        // Keep track of where the *next* line starts
-        last_line_start = idx + 1;
-      }
-    }
-
-    self.col += (s.len() - last_line_start) as u32;
-    self.dest.write_str(s)?;
-    Ok(())
-  }
-
-  /// Write a single character to the underlying destination.
-  pub fn write_char(&mut self, c: char) -> Result<(), PrinterError> {
-    if c == '\n' {
-      self.line += 1;
-      self.col = 0;
-    } else {
-      self.col += 1;
-    }
-    self.dest.write_char(c)?;
-    Ok(())
-  }
-
   /// Writes a single whitespace character, unless the `minify` option is enabled.
   ///
   /// Use `write_char` instead if you wish to force a space character to be written,
@@ -190,7 +150,8 @@ impl<'a, 'c, W: std::fmt::Write + Sized> Printer<'a, 'c, W> {
       return Ok(());
     }
 
-    self.write_char(' ')
+    self.write_char(' ')?;
+    Ok(())
   }
 
   /// Writes a delimiter character, followed by whitespace (depending on the `minify` option).
@@ -422,9 +383,52 @@ impl<'a, 'c, W: std::fmt::Write + Sized> Printer<'a, 'c, W> {
   }
 }
 
-impl<'a, 'b, 'c, W: std::fmt::Write + Sized> std::fmt::Write for Printer<'a, 'c, W> {
+impl<'a, 'c, W: std::fmt::Write + Sized> Write for Printer<'a, 'c, W> {
   fn write_str(&mut self, s: &str) -> std::fmt::Result {
-    self.col += s.len() as u32;
+    let mut last_line_start = 0;
+    for (idx, c) in s.char_indices() {
+      if c == '\n' {
+        self.line += 1;
+        last_line_start = idx + 1;
+      }
+    }
+
+    self.col = if last_line_start == 0 {
+      self.col + s.len() as u32
+    } else {
+      (s.len() - last_line_start) as u32
+    };
     self.dest.write_str(s)
   }
+
+  fn write_char(&mut self, c: char) -> std::fmt::Result {
+    if c == '\n' {
+      self.line += 1;
+      self.col = 0;
+    } else {
+      self.col += 1;
+    }
+
+    self.dest.write_char(c)
+  }
+}
+
+#[cfg(test)]
+mod tests {
+  use super::{Printer, PrinterOptions};
+  use std::fmt::Write;
+
+  #[test]
+  fn write_tracks_multiline_positions() {
+    let mut output = String::new();
+    let mut printer = Printer::new(&mut output, PrinterOptions::default());
+
+    printer.write_str("a\nbc").unwrap();
+    printer.write_char('\n').unwrap();
+    printer.write_str("d").unwrap();
+
+    assert_eq!((printer.line, printer.col), (2, 1));
+    drop(printer);
+    assert_eq!(output, "a\nbc\nd");
+  }
 }

src/properties/align.rs

@@ -16,6 +16,7 @@ use crate::vendor_prefix::VendorPrefix;
 #[cfg(feature = "visitor")]
 use crate::visitor::Visit;
 use cssparser::*;
+use std::fmt::Write;
 
 #[cfg(feature = "serde")]
 use crate::serialization::ValueWrapper;
@@ -64,9 +65,10 @@ impl ToCss for BaselinePosition {
     W: std::fmt::Write,
   {
     match self {
-      BaselinePosition::First => dest.write_str("baseline"),
-      BaselinePosition::Last => dest.write_str("last baseline"),
-    }
+      BaselinePosition::First => dest.write_str("baseline")?,
+      BaselinePosition::Last => dest.write_str("last baseline")?,
+    };
+    Ok(())
   }
 }
 
@@ -211,33 +213,34 @@ impl ToCss for JustifyContent {
     W: std::fmt::Write,
   {
     match self {
-      JustifyContent::Normal => dest.write_str("normal"),
-      JustifyContent::ContentDistribution(value) => value.to_css(dest),
+      JustifyContent::Normal => dest.write_str("normal")?,
+      JustifyContent::ContentDistribution(value) => value.to_css(dest)?,
       JustifyContent::ContentPosition { overflow, value } => {
         if let Some(overflow) = overflow {
           overflow.to_css(dest)?;
           dest.write_str(" ")?;
         }
 
-        value.to_css(dest)
+        value.to_css(dest)?;
       }
       JustifyContent::Left { overflow } => {
         if let Some(overflow) = overflow {
           overflow.to_css(dest)?;
           dest.write_str(" ")?;
         }
 
-        dest.write_str("left")
+        dest.write_str("left")?;
       }
       JustifyContent::Right { overflow } => {
         if let Some(overflow) = overflow {
           overflow.to_css(dest)?;
           dest.write_str(" ")?;
         }
 
-        dest.write_str("right")
+        dest.write_str("right")?;
       }
-    }
+    };
+    Ok(())
   }
 }
 
@@ -434,35 +437,36 @@ impl ToCss for JustifySelf {
     W: std::fmt::Write,
   {
     match self {
-      JustifySelf::Auto => dest.write_str("auto"),
-      JustifySelf::Normal => dest.write_str("normal"),
-      JustifySelf::Stretch => dest.write_str("stretch"),
-      JustifySelf::BaselinePosition(val) => val.to_css(dest),
+      JustifySelf::Auto => dest.write_str("auto")?,
+      JustifySelf::Normal => dest.write_str("normal")?,
+      JustifySelf::Stretch => dest.write_str("stretch")?,
+      JustifySelf::BaselinePosition(val) => val.to_css(dest)?,
       JustifySelf::SelfPosition { overflow, value } => {
         if let Some(overflow) = overflow {
           overflow.to_css(dest)?;
           dest.write_str(" ")?;
         }
 
-        value.to_css(dest)
+        value.to_css(dest)?;
       }
       JustifySelf::Left { overflow } => {
         if let Some(overflow) = overflow {
           overflow.to_css(dest)?;
           dest.write_str(" ")?;
         }
 
-        dest.write_str("left")
+        dest.write_str("left")?;
       }
       JustifySelf::Right { overflow } => {
         if let Some(overflow) = overflow {
           overflow.to_css(dest)?;
           dest.write_str(" ")?;
         }
 
-        dest.write_str("right")
+        dest.write_str("right")?;
       }
-    }
+    };
+    Ok(())
   }
 }
 
@@ -616,10 +620,11 @@ impl ToCss for LegacyJustify {
   {
     dest.write_str("legacy ")?;
     match self {
-      LegacyJustify::Left => dest.write_str("left"),
-      LegacyJustify::Right => dest.write_str("right"),
-      LegacyJustify::Center => dest.write_str("center"),
-    }
+      LegacyJustify::Left => dest.write_str("left")?,
+      LegacyJustify::Right => dest.write_str("right")?,
+      LegacyJustify::Center => dest.write_str("center")?,
+    };
+    Ok(())
   }
 }
 
@@ -704,35 +709,36 @@ impl ToCss for JustifyItems {
     W: std::fmt::Write,
   {
     match self {
-      JustifyItems::Normal => dest.write_str("normal"),
-      JustifyItems::Stretch => dest.write_str("stretch"),
-      JustifyItems::BaselinePosition(val) => val.to_css(dest),
-      JustifyItems::Legacy(val) => val.to_css(dest),
+      JustifyItems::Normal => dest.write_str("normal")?,
+      JustifyItems::Stretch => dest.write_str("stretch")?,
+      JustifyItems::BaselinePosition(val) => val.to_css(dest)?,
+      JustifyItems::Legacy(val) => val.to_css(dest)?,
       JustifyItems::SelfPosition { overflow, value } => {
         if let Some(overflow) = overflow {
           overflow.to_css(dest)?;
           dest.write_str(" ")?;
         }
 
-        value.to_css(dest)
+        value.to_css(dest)?;
       }
       JustifyItems::Left { overflow } => {
         if let Some(overflow) = overflow {
           overflow.to_css(dest)?;
           dest.write_str(" ")?;
         }
 
-        dest.write_str("left")
+        dest.write_str("left")?;
       }
       JustifyItems::Right { overflow } => {
         if let Some(overflow) = overflow {
           overflow.to_css(dest)?;
           dest.write_str(" ")?;
         }
 
-        dest.write_str("right")
+        dest.write_str("right")?;
       }
-    }
+    };
+    Ok(())
   }
 }