[nextest-runner] switch reporter to WriteStr (#2737)

I'd like to try using indicatif's println, which requires a string.
Complete this long-standing migration.

Author: sunshowers

cargo-nextest/src/dispatch/execution.rs

@@ -47,7 +47,6 @@ use owo_colors::OwoColorize;
 use semver::Version;
 use std::{
     env::VarError,
-    io::Write,
     sync::{Arc, OnceLock},
 };
 use tracing::{Level, info, warn};
@@ -805,7 +804,7 @@ impl ArchiveApp {
             output_file,
             |event| {
                 reporter.report_event(event, &mut writer)?;
-                writer.flush()
+                writer.write_str_flush()
             },
             redactor.clone(),
         )

cargo-nextest/src/output.rs

@@ -334,9 +334,9 @@ pub enum OutputWriter {
     #[cfg(test)]
     Test {
         /// stdout capture
-        stdout: Vec<u8>,
+        stdout: String,
         /// stderr capture
-        stderr: Vec<u8>,
+        stderr: String,
     },
 }
 
@@ -378,33 +378,15 @@ pub(crate) enum StdoutWriter<'a> {
         _lifetime: PhantomData<&'a ()>,
     },
     #[cfg(test)]
-    Test { buf: &'a mut Vec<u8> },
-}
-
-impl Write for StdoutWriter<'_> {
-    fn write(&mut self, data: &[u8]) -> std::io::Result<usize> {
-        match self {
-            Self::Normal { buf, .. } => buf.write(data),
-            #[cfg(test)]
-            Self::Test { buf } => buf.write(data),
-        }
-    }
-
-    fn flush(&mut self) -> std::io::Result<()> {
-        match self {
-            Self::Normal { buf, .. } => buf.flush(),
-            #[cfg(test)]
-            Self::Test { .. } => Ok(()),
-        }
-    }
+    Test { buf: &'a mut String },
 }
 
 impl WriteStr for StdoutWriter<'_> {
     fn write_str(&mut self, s: &str) -> io::Result<()> {
         match self {
-            Self::Normal { buf, .. } => buf.write_all(s.as_bytes()),
+            Self::Normal { buf, .. } => buf.write_str(s),
             #[cfg(test)]
-            Self::Test { buf } => buf.write_all(s.as_bytes()),
+            Self::Test { buf } => buf.write_str(s),
         }
     }
 
@@ -423,19 +405,22 @@ pub(crate) enum StderrWriter<'a> {
         _lifetime: PhantomData<&'a ()>,
     },
     #[cfg(test)]
-    Test { buf: &'a mut Vec<u8> },
+    Test { buf: &'a mut String },
 }
 
-impl Write for StderrWriter<'_> {
-    fn write(&mut self, data: &[u8]) -> std::io::Result<usize> {
+impl WriteStr for StderrWriter<'_> {
+    fn write_str(&mut self, s: &str) -> io::Result<()> {
         match self {
-            Self::Normal { buf, .. } => buf.write(data),
+            Self::Normal { buf, .. } => buf.write_str(s),
             #[cfg(test)]
-            Self::Test { buf } => buf.write(data),
+            Self::Test { buf } => {
+                buf.push_str(s);
+                Ok(())
+            }
         }
     }
 
-    fn flush(&mut self) -> std::io::Result<()> {
+    fn write_str_flush(&mut self) -> io::Result<()> {
         match self {
             Self::Normal { buf, .. } => buf.flush(),
             #[cfg(test)]

cargo-nextest/src/reuse_build.rs

@@ -12,8 +12,8 @@ use nextest_runner::{
         ArchiveFormat, ArchiveReporter, ExtractDestination, MetadataKind, MetadataWithRemap,
         PathMapper, ReuseBuildInfo, ReusedBinaryList, ReusedCargoMetadata,
     },
+    write_str::WriteStr,
 };
-use std::io::Write;
 use tracing::warn;
 
 #[derive(Debug, Default, Args)]
@@ -168,7 +168,7 @@ impl ReuseBuildOpts {
                 dest,
                 |event| {
                     reporter.report_event(event, &mut writer)?;
-                    writer.flush()
+                    writer.write_str_flush()
                 },
                 workspace_remap.as_deref(),
             )

nextest-runner/src/indenter.rs

@@ -100,6 +100,15 @@ impl<'a, D: ?Sized> Indented<'a, D> {
         self
     }
 
+    /// Skip indenting the initial line.
+    ///
+    /// This is useful when you've already written some content on the current line
+    /// and want to start indenting only from the next line onwards.
+    pub fn skip_initial(mut self) -> Self {
+        self.needs_indent = false;
+        self
+    }
+
     /// Returns the inner writer.
     pub fn into_inner(self) -> &'a mut D {
         self.inner

nextest-runner/src/reporter/displayer/formatters.rs

@@ -11,13 +11,10 @@ use crate::{
         events::{CancelReason, FinalRunStats, RunStatsFailureKind},
         helpers::Styles,
     },
+    write_str::WriteStr,
 };
 use owo_colors::OwoColorize;
-use std::{
-    fmt,
-    io::{self, Write},
-    time::Duration,
-};
+use std::{fmt, io, time::Duration};
 
 pub(super) struct DisplayBracketedHhMmSs(pub(super) Duration);
 
@@ -102,7 +99,7 @@ pub(super) fn write_skip_counts(
     skip_counts: &SkipCounts,
     default_filter: &CompiledDefaultFilter,
     styles: &Styles,
-    writer: &mut dyn Write,
+    writer: &mut dyn WriteStr,
 ) -> io::Result<()> {
     if skip_counts.skipped_tests > 0 || skip_counts.skipped_binaries > 0 {
         write!(writer, " (")?;
@@ -154,7 +151,7 @@ fn write_skip_counts_impl(
     skipped_tests: usize,
     skipped_binaries: usize,
     styles: &Styles,
-    writer: &mut dyn Write,
+    writer: &mut dyn WriteStr,
 ) -> io::Result<()> {
     // X tests and Y binaries skipped, or X tests skipped, or Y binaries skipped.
     if skipped_tests > 0 && skipped_binaries > 0 {
@@ -188,7 +185,7 @@ fn write_skip_counts_impl(
 pub(super) fn write_final_warnings(
     final_stats: FinalRunStats,
     styles: &Styles,
-    writer: &mut dyn Write,
+    writer: &mut dyn WriteStr,
 ) -> io::Result<()> {
     match final_stats {
         FinalRunStats::Failed(RunStatsFailureKind::Test {
@@ -224,7 +221,7 @@ fn write_final_warnings_for_failure(
     not_run: usize,
     reason: Option<CancelReason>,
     styles: &Styles,
-    writer: &mut dyn Write,
+    writer: &mut dyn WriteStr,
 ) -> io::Result<()> {
     match reason {
         Some(reason @ CancelReason::TestFailure | reason @ CancelReason::TestFailureImmediate) => {
@@ -379,7 +376,7 @@ mod tests {
     }
 
     fn skip_counts_str(skip_counts: &SkipCounts, override_section: bool) -> String {
-        let mut buf = Vec::new();
+        let mut buf = String::new();
         write_skip_counts(
             skip_counts,
             &CompiledDefaultFilter {
@@ -395,7 +392,7 @@ mod tests {
             &mut buf,
         )
         .unwrap();
-        String::from_utf8(buf).unwrap()
+        buf
     }
 
     #[test]
@@ -449,9 +446,9 @@ mod tests {
     }
 
     fn final_warnings_for(stats: FinalRunStats) -> String {
-        let mut buf: Vec<u8> = Vec::new();
+        let mut buf = String::new();
         let styles = Styles::default();
         write_final_warnings(stats, &styles, &mut buf).unwrap();
-        String::from_utf8(buf).unwrap()
+        buf
     }
 }