Add a verbose-diff option

And don't print end of line characters by default in diffs

cc #2536

Author: nrc

src/bin/main.rs

@@ -93,6 +93,7 @@ enum Operation {
 struct CliOptions {
     skip_children: Option<bool>,
     verbose: bool,
+    verbose_diff: bool,
     write_mode: Option<WriteMode>,
     color: Option<Color>,
     file_lines: FileLines, // Default is all lines in all files.
@@ -104,6 +105,8 @@ impl CliOptions {
     fn from_matches(matches: &Matches) -> FmtResult<CliOptions> {
         let mut options = CliOptions::default();
         options.verbose = matches.opt_present("verbose");
+        options.verbose_diff = matches.opt_present("verbose-diff");
+
         let unstable_features = matches.opt_present("unstable-features");
         let rust_nightly = option_env!("CFG_RELEASE_CHANNEL")
             .map(|c| c == "nightly")
@@ -150,6 +153,7 @@ impl CliOptions {
 
     fn apply_to(self, config: &mut Config) {
         config.set().verbose(self.verbose);
+        config.set().verbose_diff(self.verbose_diff);
         config.set().file_lines(self.file_lines);
         config.set().unstable_features(self.unstable_features);
         if let Some(skip_children) = self.skip_children {
@@ -227,6 +231,11 @@ fn make_opts() -> Options {
         "Format specified line ranges. See README for more detail on the JSON format.",
         "JSON",
     );
+    opts.optflag(
+        "",
+        "verbose-diff",
+        "Emit a more verbose diff, indicating the end of lines.",
+    );
     opts.optflag("h", "help", "Show this message");
     opts.optflag("", "skip-children", "Don't reformat child modules");
     opts.optflag(

src/config/config_type.rs

@@ -356,7 +356,8 @@ macro_rules! create_config {
             }
 
             pub fn is_hidden_option(name: &str) -> bool {
-                const HIDE_OPTIONS: [&str; 3] = ["verbose", "file_lines", "width_heuristics"];
+                const HIDE_OPTIONS: [&str; 4] =
+                    ["verbose", "verbose_diff", "file_lines", "width_heuristics"];
                 HIDE_OPTIONS.contains(&name)
             }
 

src/config/mod.rs

@@ -143,6 +143,7 @@ create_config! {
 
     // Not user-facing
     verbose: bool, false, false, "Use verbose output";
+    verbose_diff: bool, false, false, "Emit verbose diffs";
     file_lines: FileLines, FileLines::all(), false,
         "Lines to format; this is not supported in rustfmt.toml, and can only be specified \
          via the --file-lines option";

src/filemap.rs

@@ -159,7 +159,7 @@ where
                 print_diff(
                     mismatch,
                     |line_num| format!("Diff in {} at line {}:", filename.display(), line_num),
-                    config.color(),
+                    config,
                 );
                 return Ok(has_diff);
             }
@@ -186,7 +186,7 @@ where
                 print_diff(
                     mismatch,
                     |line_num| format!("Diff in {} at line {}:", filename.display(), line_num),
-                    config.color(),
+                    config,
                 );
                 return Ok(has_diff);
             }

src/rustfmt_diff.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use config::Color;
+use config::{Color, Config};
 use diff;
 use std::collections::VecDeque;
 use std::io;
@@ -149,10 +149,13 @@ pub fn make_diff(expected: &str, actual: &str, context_size: usize) -> Vec<Misma
     results
 }
 
-pub fn print_diff<F>(diff: Vec<Mismatch>, get_section_title: F, color: Color)
+pub fn print_diff<F>(diff: Vec<Mismatch>, get_section_title: F, config: &Config)
 where
     F: Fn(u32) -> String,
 {
+    let color = config.color();
+    let line_terminator = if config.verbose_diff() { "⏎" } else { "" };
+
     let mut writer = OutputWriter::new(color);
 
     for mismatch in diff {
@@ -161,13 +164,17 @@ where
 
         for line in mismatch.lines {
             match line {
-                DiffLine::Context(ref str) => writer.writeln(&format!(" {}⏎", str), None),
-                DiffLine::Expected(ref str) => {
-                    writer.writeln(&format!("+{}⏎", str), Some(term::color::GREEN))
-                }
-                DiffLine::Resulting(ref str) => {
-                    writer.writeln(&format!("-{}⏎", str), Some(term::color::RED))
+                DiffLine::Context(ref str) => {
+                    writer.writeln(&format!(" {}{}", str, line_terminator), None)
                 }
+                DiffLine::Expected(ref str) => writer.writeln(
+                    &format!("+{}{}", str, line_terminator),
+                    Some(term::color::GREEN),
+                ),
+                DiffLine::Resulting(ref str) => writer.writeln(
+                    &format!("-{}{}", str, line_terminator),
+                    Some(term::color::RED),
+                ),
             }
         }
     }

tests/lib.rs

@@ -337,7 +337,7 @@ fn print_mismatches_default_message(result: HashMap<PathBuf, Vec<Mismatch>>) {
     for (file_name, diff) in result {
         let mismatch_msg_formatter =
             |line_num| format!("\nMismatch at {}:{}:", file_name.display(), line_num);
-        print_diff(diff, &mismatch_msg_formatter, Color::Auto);
+        print_diff(diff, &mismatch_msg_formatter, &Default::default());
     }
 
     if let Some(mut t) = term::stdout() {
@@ -350,7 +350,7 @@ fn print_mismatches<T: Fn(u32) -> String>(
     mismatch_msg_formatter: T,
 ) {
     for (_file_name, diff) in result {
-        print_diff(diff, &mismatch_msg_formatter, Color::Auto);
+        print_diff(diff, &mismatch_msg_formatter, &Default::default());
     }
 
     if let Some(mut t) = term::stdout() {