feat(report): wrap multiline messages to keep formatting

Fixes: https://github.com/zkat/miette/issues/51

Cargo.toml

@@ -18,6 +18,7 @@ once_cell = "1.8.0"
 owo-colors = "2.0.0"
 atty = "0.2.14"
 ci_info = "0.14.2"
+textwrap = "0.14.2"
 
 [dev-dependencies]
 semver = "1.0.4"

src/handlers/graphical.rs

@@ -101,8 +101,13 @@ impl GraphicalReportHandler {
         }
         writeln!(f, "{}", self.theme.characters.hbar.to_string().repeat(20),)?;
         writeln!(f)?;
-        write!(f, "    {} ", severity_icon.style(severity_style))?;
-        writeln!(f, "{}", diagnostic,)?;
+        // TODO: terminal width support
+        let initial_indent = format!("    {} ", severity_icon.style(severity_style));
+        let rest_indent = format!("    {} ", self.theme.characters.vbar.style(severity_style));
+        let opts = textwrap::Options::new(80)
+            .initial_indent(&initial_indent)
+            .subsequent_indent(&rest_indent);
+        writeln!(f, "{}", textwrap::fill(&diagnostic.to_string(), opts))?;
         Ok(())
     }
 
@@ -121,13 +126,19 @@ impl GraphicalReportHandler {
                 } else {
                     self.theme.characters.lbot
                 };
-                let prefix = format!(
-                    "    {}{}{}",
+                let initial_indent = format!(
+                    "    {}{}{} ",
                     char, self.theme.characters.hbar, self.theme.characters.rarrow
                 )
                 .style(severity_style)
                 .to_string();
-                writeln!(f, "{} {}", prefix, error)?;
+                let rest_indent = format!("    {}   ", self.theme.characters.vbar)
+                    .style(severity_style)
+                    .to_string();
+                let opts = textwrap::Options::new(80)
+                    .initial_indent(&initial_indent)
+                    .subsequent_indent(&rest_indent);
+                writeln!(f, "{}", textwrap::fill(&error.to_string(), opts))?;
             }
         }
 

tests/printer.rs

@@ -340,7 +340,7 @@ line5
 #[test]
 fn multiline_highlight_no_label() -> Result<(), MietteError> {
     #[derive(Debug, Diagnostic, Error)]
-    #[error("wtf?!")]
+    #[error("wtf?!\nit broke :(")]
     #[diagnostic(code(oops::my::bad), help("try doing it better next time?"))]
     struct MyBad {
         #[source]
@@ -355,7 +355,7 @@ fn multiline_highlight_no_label() -> Result<(), MietteError> {
     }
 
     #[derive(Debug, Error)]
-    #[error("something went wrong")]
+    #[error("something went wrong\n\nHere's a more detailed explanation of everything that actually went wrong because it's actually important.\n")]
     struct Inner(#[source] InnerInner);
 
     #[derive(Debug, Error)]
@@ -379,11 +379,16 @@ line5
     };
     let out = fmt_report(err.into());
     println!("{}", out);
-    let expected = r#"
+    let expected = "
 ────[oops::my::bad]────────────────────
 
     × wtf?!
+    │ it broke :(
     ├─▶ something went wrong
+    │\u{20}\u{20}\u{20}
+    │   Here's a more detailed explanation of everything that actually went
+    │   wrong because it's actually important.
+    │\u{20}\u{20}\u{20}
     ╰─▶ very much went wrong
 
    ╭───[bad_file.rs:1:1] This is the part that broke:
@@ -396,7 +401,7 @@ line5
    ╰───
 
     ‽ try doing it better next time?
-"#
+"
     .trim_start()
     .to_string();
     assert_eq!(expected, out);