feat(printer): lots of small improvements to printer

Cargo.toml

@@ -11,7 +11,6 @@ readme = "README.md"
 edition = "2018"
 
 [dependencies]
-indenter = "0.3.3"
 thiserror = "1.0.26"
 miette-derive = { version = "=0.11.0", path = "miette-derive" }
 once_cell = "1.8.0"

src/printer/default_printer.rs

@@ -1,12 +1,11 @@
 use std::fmt;
 
-use indenter::indented;
 use owo_colors::{OwoColorize, Style};
 
 use crate::chain::Chain;
 use crate::printer::theme::*;
 use crate::protocol::{Diagnostic, DiagnosticReportPrinter, DiagnosticSnippet, Severity};
-use crate::SourceSpan;
+use crate::{SourceSpan, SpanContents};
 
 /**
 Reference implementation of the [DiagnosticReportPrinter] trait. This is generally
@@ -44,13 +43,10 @@ impl DefaultReportPrinter {
     ) -> fmt::Result {
         self.render_header(f, diagnostic)?;
         self.render_causes(f, diagnostic)?;
+
         if let Some(snippets) = diagnostic.snippets() {
-            let mut pre = false;
             for snippet in snippets {
-                if !pre {
+                writeln!(f)?;
-                    writeln!(f)?;
-                    pre = true;
-                }
                 self.render_snippet(f, &snippet)?;
             }
         }
@@ -60,41 +56,46 @@ impl DefaultReportPrinter {
     }
 
     fn render_header(&self, f: &mut impl fmt::Write, diagnostic: &(dyn Diagnostic)) -> fmt::Result {
-        let sev = match diagnostic.severity() {
+        let (severity_style, severity_icon) = match diagnostic.severity() {
-            Some(Severity::Error) | None => "Error".style(self.theme.styles.error),
+            Some(Severity::Error) | None => (self.theme.styles.error, self.theme.characters.x),
-            Some(Severity::Warning) => "Warning".style(self.theme.styles.warning),
+            Some(Severity::Warning) => (self.theme.styles.warning, self.theme.characters.warning),
-            Some(Severity::Advice) => "Advice".style(self.theme.styles.advice),
+            Some(Severity::Advice) => (self.theme.styles.advice, self.theme.characters.point_right),
-        }
+        };
-        .to_string();
         let code = diagnostic.code();
-        let msg = diagnostic.to_string();
         writeln!(
             f,
-            "{} [{}]: {}",
+            "{}[{}]{}",
-            sev,
+            self.theme.characters.hbar.to_string().repeat(4),
             code.style(self.theme.styles.code),
-            msg
+            self.theme.characters.hbar.to_string().repeat(20),
+        )?;
+        writeln!(f)?;
+        writeln!(
+            f,
+            "    {} {}",
+            severity_icon.style(severity_style),
+            diagnostic.style(severity_style)
         )?;
         Ok(())
     }
 
     fn render_causes(&self, f: &mut impl fmt::Write, diagnostic: &(dyn Diagnostic)) -> fmt::Result {
-        use fmt::Write as _;
+        let severity_style = match diagnostic.severity() {
+            Some(Severity::Error) | None => self.theme.styles.error,
+            Some(Severity::Warning) => self.theme.styles.warning,
+            Some(Severity::Advice) => self.theme.styles.advice,
+        };
 
         if let Some(cause) = diagnostic.source() {
-            writeln!(f)?;
+            let mut cause_iter = Chain::new(cause).peekable();
-            write!(f, "Caused by:")?;
+            while let Some(error) = cause_iter.next() {
-
+                let char = if cause_iter.peek().is_some() {
-            let multiple = cause.source().is_some();
+                    self.theme.characters.lcross
-
-            for (n, error) in Chain::new(cause).enumerate() {
-                let msg = format!("{}", error);
-                writeln!(f)?;
-                if multiple {
-                    write!(indented(f).ind(n), "{}", msg)?;
                 } else {
-                    write!(indented(f), "{}", msg)?;
+                    self.theme.characters.lbot
-                }
+                };
+                let msg = format!("    {}{}{} {}", char, self.theme.characters.hbar, self.theme.characters.rarrow, error).style(severity_style).to_string();
+                writeln!(f, "{}", msg)?;
             }
         }
 
@@ -105,27 +106,13 @@ impl DefaultReportPrinter {
         if let Some(help) = diagnostic.help() {
             let help = help.style(self.theme.styles.help);
             writeln!(f)?;
-            writeln!(f, "{} {}", self.theme.characters.eq, help)?;
+            writeln!(f, "    {} {}", self.theme.characters.fyi, help)?;
         }
         Ok(())
     }
 
     fn render_snippet(&self, f: &mut impl fmt::Write, snippet: &DiagnosticSnippet) -> fmt::Result {
-        // Boring: The Header
+        let (contents, lines) = self.get_lines(snippet)?;
-        if let Some(source_name) = snippet.context.label() {
-            let source_name = source_name.style(self.theme.styles.filename);
-            write!(f, "[{}]", source_name)?;
-        }
-        if let Some(msg) = &snippet.message {
-            write!(f, " {}:", msg)?;
-        }
-        writeln!(f)?;
-        writeln!(f)?;
-
-        // Fun time!
-
-        // Our actual code, line by line! Handy!
-        let lines = self.get_lines(snippet)?;
 
         // Highlights are the bits we're going to underline in our overall
         // snippet, and we need to do some analysis first to come up with
@@ -161,6 +148,25 @@ impl DefaultReportPrinter {
             .to_string()
             .len();
 
+        // Header
+        if let Some(source_name) = snippet.context.label() {
+            let source_name = source_name.style(self.theme.styles.filename);
+            write!(
+                f,
+                "{}{}{}[{}:{}:{}]",
+                " ".repeat(linum_width + 2),
+                self.theme.characters.ltop,
+                self.theme.characters.hbar.to_string().repeat(3),
+                source_name,
+                contents.line() + 1,
+                contents.column() + 1
+            )?;
+            if let Some(msg) = &snippet.message {
+                write!(f, " {}:", msg)?;
+            }
+            writeln!(f)?;
+        }
+
         // Now it's time for the fun part--actually rendering everything!
         for line in &lines {
             // Line number, appropriately padded.
@@ -222,7 +228,7 @@ impl DefaultReportPrinter {
         let mut arrow = false;
         for (i, hl) in applicable.enumerate() {
             if line.span_starts(hl) {
-                gutter.push_str(&chars.ltop.to_string().style(hl.style).to_string());
+                gutter.push_str(&chars.ltop.style(hl.style).to_string());
                 gutter.push_str(
                     &chars
                         .hbar
@@ -231,14 +237,14 @@ impl DefaultReportPrinter {
                         .style(hl.style)
                         .to_string(),
                 );
-                gutter.push_str(&chars.rarrow.to_string().style(hl.style).to_string());
+                gutter.push_str(&chars.rarrow.style(hl.style).to_string());
                 arrow = true;
                 break;
             } else if line.span_ends(hl) {
                 if hl.label().is_some() {
-                    gutter.push_str(&chars.lcross.to_string().style(hl.style).to_string());
+                    gutter.push_str(&chars.lcross.style(hl.style).to_string());
                 } else {
-                    gutter.push_str(&chars.lbot.to_string().style(hl.style).to_string());
+                    gutter.push_str(&chars.lbot.style(hl.style).to_string());
                 }
                 gutter.push_str(
                     &chars
@@ -248,11 +254,11 @@ impl DefaultReportPrinter {
                         .style(hl.style)
                         .to_string(),
                 );
-                gutter.push_str(&chars.rarrow.to_string().style(hl.style).to_string());
+                gutter.push_str(&chars.rarrow.style(hl.style).to_string());
                 arrow = true;
                 break;
             } else if line.span_flyby(hl) {
-                gutter.push_str(&chars.vbar.to_string().style(hl.style).to_string());
+                gutter.push_str(&chars.vbar.style(hl.style).to_string());
             } else {
                 gutter.push(' ');
             }
@@ -283,7 +289,7 @@ impl DefaultReportPrinter {
         let applicable = highlights.iter().filter(|hl| line.span_applies(hl));
         for (i, hl) in applicable.enumerate() {
             if !line.span_line_only(hl) && line.span_ends(hl) {
-                gutter.push_str(&chars.lbot.to_string().style(hl.style).to_string());
+                gutter.push_str(&chars.lbot.style(hl.style).to_string());
                 gutter.push_str(
                     &chars
                         .hbar
@@ -294,7 +300,7 @@ impl DefaultReportPrinter {
                 );
                 break;
             } else {
-                gutter.push_str(&chars.vbar.to_string().style(hl.style).to_string());
+                gutter.push_str(&chars.vbar.style(hl.style).to_string());
             }
         }
         write!(f, "{:width$}", gutter, width = max_gutter + 1)?;
@@ -389,13 +395,16 @@ impl DefaultReportPrinter {
         writeln!(
             f,
             "{} {}",
-            self.theme.characters.hbar.to_string().style(hl.style),
+            self.theme.characters.hbar.style(hl.style),
             hl.label().unwrap_or_else(|| "".into()),
         )?;
         Ok(())
     }
 
-    fn get_lines(&self, snippet: &DiagnosticSnippet) -> Result<Vec<Line>, fmt::Error> {
+    fn get_lines<'a>(
+        &'a self,
+        snippet: &'a DiagnosticSnippet,
+    ) -> Result<(Box<dyn SpanContents + 'a>, Vec<Line>), fmt::Error> {
         let context_data = snippet
             .source
             .read_span(&snippet.context)
@@ -445,7 +454,7 @@ impl DefaultReportPrinter {
                 line_offset = offset;
             }
         }
-        Ok(lines)
+        Ok((context_data, lines))
     }
 }
 

src/printer/mod.rs

@@ -9,10 +9,10 @@ use once_cell::sync::OnceCell;
 use crate::protocol::{Diagnostic, DiagnosticReportPrinter, Severity};
 use crate::MietteError;
 
-pub use default_reporter::*;
+pub use default_printer::*;
 pub use theme::*;
 
-mod default_reporter;
+mod default_printer;
 mod theme;
 
 static REPORTER: OnceCell<Box<dyn DiagnosticReportPrinter + Send + Sync + 'static>> =

src/printer/theme.rs

@@ -65,8 +65,8 @@ impl MietteStyles {
             advice: style().cyan(),
             code: style().yellow(),
             help: style().cyan(),
-            filename: style().green(),
+            filename: style().cyan().underline().bold(),
-            highlights: vec![style().red(), style().magenta(), style().cyan()],
+            highlights: vec![style().red().bold(), style().yellow().bold(), style().cyan().bold()],
         }
     }
 
@@ -111,7 +111,10 @@ pub struct MietteCharacters {
     pub underbar: char,
     pub underline: char,
 
-    pub eq: char,
+    pub fyi: char,
+    pub x: char,
+    pub warning: char,
+    pub point_right: char,
 }
 
 impl MietteCharacters {
@@ -135,7 +138,10 @@ impl MietteCharacters {
             rcross: '┤',
             underbar: '┬',
             underline: '─',
-            eq: '﹦',
+            fyi: '‽',
+            x: '×',
+            warning: '⚠',
+            point_right: '☞',
         }
     }
 
@@ -159,7 +165,10 @@ impl MietteCharacters {
             rcross: '|',
             underbar: '|',
             underline: '^',
-            eq: '=',
+            fyi: 'i',
+            x: 'x',
+            warning: '!',
+            point_right: '>',
         }
     }
 }

tests/printer.rs

@@ -40,7 +40,21 @@ fn single_line_highlight() -> Result<(), MietteError> {
     };
     let out = fmt_report(err.into());
     println!("{}", out);
-    assert_eq!("Error [oops::my::bad]: oops!\n\n[bad_file.rs] This is the part that broke:\n\n 1 │ source\n 2 │   text\n   ·   ──┬─\n   ·     ╰── this bit here\n 3 │     here\n\n﹦ try doing it better next time?\n".to_string(), out);
+    let expected = r#"
+────[oops::my::bad]────────────────────
+
+    × oops!
+
+   ╭───[bad_file.rs:1:1] This is the part that broke:
+ 1 │ source
+ 2 │   text
+   ·   ──┬─
+   ·     ╰── this bit here
+ 3 │     here
+
+    ‽ try doing it better next time?
+"#.trim_start().to_string();
+    assert_eq!(expected, out);
     Ok(())
 }
 
@@ -66,7 +80,20 @@ fn single_line_highlight_no_label() -> Result<(), MietteError> {
     };
     let out = fmt_report(err.into());
     println!("{}", out);
-    assert_eq!("Error [oops::my::bad]: oops!\n\n[bad_file.rs] This is the part that broke:\n\n 1 │ source\n 2 │   text\n   ·   ────\n 3 │     here\n\n﹦ try doing it better next time?\n".to_string(), out);
+    let expected = r#"
+────[oops::my::bad]────────────────────
+
+    × oops!
+
+   ╭───[bad_file.rs:1:1] This is the part that broke:
+ 1 │ source
+ 2 │   text
+   ·   ────
+ 3 │     here
+
+    ‽ try doing it better next time?
+"#.trim_start().to_string();
+    assert_eq!(expected, out);
     Ok(())
 }
 
@@ -95,7 +122,22 @@ fn multiple_same_line_highlights() -> Result<(), MietteError> {
     };
     let out = fmt_report(err.into());
     println!("{}", out);
-    assert_eq!("Error [oops::my::bad]: oops!\n\n[bad_file.rs] This is the part that broke:\n\n 1 │ source\n 2 │   text text text text text\n   ·   ──┬─ ──┬─\n   ·     ╰── this bit here\n   ·          ╰── also this bit\n 3 │     here\n\n﹦ try doing it better next time?\n".to_string(), out);
+    let expected = r#"
+────[oops::my::bad]────────────────────
+
+    × oops!
+
+   ╭───[bad_file.rs:1:1] This is the part that broke:
+ 1 │ source
+ 2 │   text text text text text
+   ·   ──┬─ ──┬─
+   ·     ╰── this bit here
+   ·          ╰── also this bit
+ 3 │     here
+
+    ‽ try doing it better next time?
+"#.trim_start().to_string();
+    assert_eq!(expected, out);
     Ok(())
 }
 
@@ -121,7 +163,20 @@ fn multiline_highlight_adjacent() -> Result<(), MietteError> {
     };
     let out = fmt_report(err.into());
     println!("{}", out);
-    assert_eq!("Error [oops::my::bad]: oops!\n\n[bad_file.rs] This is the part that broke:\n\n 1 │     source\n 2 │ ╭─▶   text\n 3 │ ├─▶     here\n   · ╰──── these two lines\n\n﹦ try doing it better next time?\n".to_string(), out);
+    let expected = r#"
+────[oops::my::bad]────────────────────
+
+    × oops!
+
+   ╭───[bad_file.rs:1:1] This is the part that broke:
+ 1 │     source
+ 2 │ ╭─▶   text
+ 3 │ ├─▶     here
+   · ╰──── these two lines
+
+    ‽ try doing it better next time?
+"#.trim_start().to_string();
+    assert_eq!(expected, out);
     Ok(())
 }
 
@@ -156,7 +211,23 @@ line5
     };
     let out = fmt_report(err.into());
     println!("{}", out);
-    assert_eq!("Error [oops::my::bad]: oops!\n\n[bad_file.rs] This is the part that broke:\n\n 1 │ ╭──▶ line1\n 2 │ │╭─▶ line2\n 3 │ ││   line3\n 4 │ │├─▶ line4\n   · │╰──── block 2\n 6 │ ├──▶ line5\n   · ╰───── block 1\n\n﹦ try doing it better next time?\n".to_string(), out);
+    let expected =r#"
+────[oops::my::bad]────────────────────
+
+    × oops!
+
+   ╭───[bad_file.rs:1:1] This is the part that broke:
+ 1 │ ╭──▶ line1
+ 2 │ │╭─▶ line2
+ 3 │ ││   line3
+ 4 │ │├─▶ line4
+   · │╰──── block 2
+ 6 │ ├──▶ line5
+   · ╰───── block 1
+
+    ‽ try doing it better next time?
+"#.trim_start().to_string();
+    assert_eq!(expected, out);
     Ok(())
 }
 
@@ -191,7 +262,22 @@ line5
     };
     let out = fmt_report(err.into());
     println!("{}", out);
-    assert_eq!("Error [oops::my::bad]: oops!\n\n[bad_file.rs] This is the part that broke:\n\n 1 │ ╭──▶ line1\n 2 │ │╭─▶ line2\n 3 │ ││   line3\n 4 │ │╰─▶ line4\n 6 │ ├──▶ line5\n   · ╰───── block 1\n\n﹦ try doing it better next time?\n".to_string(), out);
+    let expected = r#"
+────[oops::my::bad]────────────────────
+
+    × oops!
+
+   ╭───[bad_file.rs:1:1] This is the part that broke:
+ 1 │ ╭──▶ line1
+ 2 │ │╭─▶ line2
+ 3 │ ││   line3
+ 4 │ │╰─▶ line4
+ 6 │ ├──▶ line5
+   · ╰───── block 1
+
+    ‽ try doing it better next time?
+"#.trim_start().to_string();
+    assert_eq!(expected, out);
     Ok(())
 }
 
@@ -220,7 +306,22 @@ fn multiple_multiline_highlights_adjacent() -> Result<(), MietteError> {
     };
     let out = fmt_report(err.into());
     println!("{}", out);
-    assert_eq!("Error [oops::my::bad]: oops!\n\n[bad_file.rs] This is the part that broke:\n\n 1 │ ╭─▶ source\n 2 │ ├─▶   text\n   · ╰──── this bit here\n 3 │ ╭─▶     here\n 4 │ ├─▶ more here\n   · ╰──── also this bit\n\n﹦ try doing it better next time?\n".to_string(), out);
+    let expected =r#"
+────[oops::my::bad]────────────────────
+
+    × oops!
+
+   ╭───[bad_file.rs:1:1] This is the part that broke:
+ 1 │ ╭─▶ source
+ 2 │ ├─▶   text
+   · ╰──── this bit here
+ 3 │ ╭─▶     here
+ 4 │ ├─▶ more here
+   · ╰──── also this bit
+
+    ‽ try doing it better next time?
+"#.trim_start().to_string();
+    assert_eq!(expected, out);
     Ok(())
 }