refactor(fmt): Reduce duplication in DefaultFormatWriter

Author: epage

src/fmt/mod.rs

@@ -231,22 +231,9 @@ impl Builder {
         } else {
             Box::new(move |buf, record| {
                 let fmt = DefaultFormatWriter {
-                    timestamp: built.default_format.timestamp,
-                    module_path: built.default_format.module_path,
-                    target: built.default_format.target,
-                    level: built.default_format.level,
-                    written_header_value: false,
-                    indent: built.default_format.indent,
-                    suffix: built.default_format.suffix,
-                    source_file: built.default_format.source_file,
-                    source_line_number: built.default_format.source_line_number,
-                    #[cfg(feature = "kv")]
-                    kv_format: built
-                        .default_format
-                        .kv_format
-                        .as_deref()
-                        .unwrap_or(&default_kv_format),
+                    format: &built.default_format,
                     buf,
+                    written_header_value: false,
                 };
 
                 fmt.write(record)
@@ -321,18 +308,9 @@ impl Default for DefaultFormat {
 ///
 /// This format needs to work with any combination of crate features.
 struct DefaultFormatWriter<'a> {
-    timestamp: Option<TimestampPrecision>,
-    module_path: bool,
-    target: bool,
-    level: bool,
-    source_file: bool,
-    source_line_number: bool,
-    written_header_value: bool,
-    indent: Option<usize>,
+    format: &'a DefaultFormat,
     buf: &'a mut Formatter,
-    suffix: &'a str,
-    #[cfg(feature = "kv")]
-    kv_format: &'a KvFormatFn,
+    written_header_value: bool,
 }
 
 impl DefaultFormatWriter<'_> {
@@ -347,7 +325,7 @@ impl DefaultFormatWriter<'_> {
         self.write_args(record)?;
         #[cfg(feature = "kv")]
         self.write_kv(record)?;
-        write!(self.buf, "{}", self.suffix)
+        write!(self.buf, "{}", self.format.suffix)
     }
 
     fn subtle_style(&self, text: &'static str) -> SubtleStyle {
@@ -383,7 +361,7 @@ impl DefaultFormatWriter<'_> {
     }
 
     fn write_level(&mut self, record: &Record<'_>) -> io::Result<()> {
-        if !self.level {
+        if !self.format.level {
             return Ok(());
         }
 
@@ -409,7 +387,7 @@ impl DefaultFormatWriter<'_> {
         #[cfg(feature = "humantime")]
         {
             use self::TimestampPrecision::{Micros, Millis, Nanos, Seconds};
-            let ts = match self.timestamp {
+            let ts = match self.format.timestamp {
                 None => return Ok(()),
                 Some(Seconds) => self.buf.timestamp_seconds(),
                 Some(Millis) => self.buf.timestamp_millis(),
@@ -429,7 +407,7 @@ impl DefaultFormatWriter<'_> {
     }
 
     fn write_module_path(&mut self, record: &Record<'_>) -> io::Result<()> {
-        if !self.module_path {
+        if !self.format.module_path {
             return Ok(());
         }
 
@@ -441,12 +419,16 @@ impl DefaultFormatWriter<'_> {
     }
 
     fn write_source_location(&mut self, record: &Record<'_>) -> io::Result<()> {
-        if !self.source_file {
+        if !self.format.source_file {
             return Ok(());
         }
 
         if let Some(file_path) = record.file() {
-            let line = self.source_line_number.then(|| record.line()).flatten();
+            let line = self
+                .format
+                .source_line_number
+                .then(|| record.line())
+                .flatten();
             match line {
                 Some(line) => self.write_header_value(format_args!("{file_path}:{line}")),
                 None => self.write_header_value(file_path),
@@ -457,7 +439,7 @@ impl DefaultFormatWriter<'_> {
     }
 
     fn write_target(&mut self, record: &Record<'_>) -> io::Result<()> {
-        if !self.target {
+        if !self.format.target {
             return Ok(());
         }
 
@@ -477,7 +459,7 @@ impl DefaultFormatWriter<'_> {
     }
 
     fn write_args(&mut self, record: &Record<'_>) -> io::Result<()> {
-        match self.indent {
+        match self.format.indent {
             // Fast path for no indentation
             None => write!(self.buf, "{}", record.args()),
 
@@ -497,7 +479,7 @@ impl DefaultFormatWriter<'_> {
                                 write!(
                                     self.fmt.buf,
                                     "{}{:width$}",
-                                    self.fmt.suffix,
+                                    self.fmt.format.suffix,
                                     "",
                                     width = self.indent_count
                                 )?;
@@ -530,7 +512,11 @@ impl DefaultFormatWriter<'_> {
 
     #[cfg(feature = "kv")]
     fn write_kv(&mut self, record: &Record<'_>) -> io::Result<()> {
-        let format = self.kv_format;
+        let format = self
+            .format
+            .kv_format
+            .as_deref()
+            .unwrap_or(&default_kv_format);
         format(self.buf, record.key_values())
     }
 }