feature: add support for disabling the primary label line/col information

src/handlers/graphical.rs

@@ -33,6 +33,7 @@ pub struct GraphicalReportHandler {
     pub(crate) with_cause_chain: bool,
     pub(crate) wrap_lines: bool,
     pub(crate) break_words: bool,
+    pub(crate) with_primary_span_start: bool,
     pub(crate) word_separator: Option<textwrap::WordSeparator>,
     pub(crate) word_splitter: Option<textwrap::WordSplitter>,
     pub(crate) highlighter: MietteHighlighter,
@@ -61,6 +62,7 @@ impl GraphicalReportHandler {
             with_cause_chain: true,
             wrap_lines: true,
             break_words: true,
+            with_primary_span_start: true,
             word_separator: None,
             word_splitter: None,
             highlighter: MietteHighlighter::default(),
@@ -80,6 +82,7 @@ impl GraphicalReportHandler {
             tab_width: 4,
             wrap_lines: true,
             with_cause_chain: true,
+            with_primary_span_start: true,
             break_words: true,
             word_separator: None,
             word_splitter: None,
@@ -119,6 +122,20 @@ impl GraphicalReportHandler {
         self
     }
 
+    /// Include the line and column for the the start of the primary span when the
+    /// snippet extends multiple lines
+    pub fn with_primary_span_start(mut self) -> Self {
+        self.with_primary_span_start = true;
+        self
+    }
+
+    /// Do not include the line and column for the the start of the primary span
+    /// when the snippet extends multiple lines
+    pub fn without_primary_span_start(mut self) -> Self {
+        self.with_primary_span_start = false;
+        self
+    }
+
     /// Whether to include [`Diagnostic::url()`] in the output.
     ///
     /// Disabling this is not recommended, but can be useful for more easily
@@ -654,6 +671,7 @@ impl GraphicalReportHandler {
         };
 
         if let Some(source_name) = primary_contents.name() {
+            if self.with_primary_span_start {
                 writeln!(
                     f,
                     "[{}]",
@@ -665,15 +683,22 @@ impl GraphicalReportHandler {
                     )
                     .style(self.theme.styles.link)
                 )?;
-        } else if lines.len() <= 1 {
-            writeln!(f, "{}", self.theme.characters.hbar.to_string().repeat(3))?;
             } else {
+                writeln!(
+                    f,
+                    "[{}]",
+                    format_args!("{}", source_name,).style(self.theme.styles.link)
+                )?;
+            }
+        } else if self.with_primary_span_start && lines.len() > 1 {
             writeln!(
                 f,
                 "[{}:{}]",
                 primary_contents.line() + 1,
                 primary_contents.column() + 1
             )?;
+        } else {
+            writeln!(f, "{}", self.theme.characters.hbar.to_string().repeat(3))?;
         }
 
         // Now it's time for the fun part--actually rendering everything!

tests/graphical.rs

@@ -2510,3 +2510,63 @@ fn after_invalid_unicode() -> Result<(), MietteError> {
 
     Ok(())
 }
+
+#[test]
+fn option_include_primary_span_start() {
+    #[derive(Debug, Clone, Diagnostic, Error)]
+    #[error("decoding error")]
+    #[diagnostic(code(decode_err))]
+    struct E {
+        #[label("valid data here")]
+        src: SourceSpan,
+    }
+
+    let invalid_source: &[u8] = b"malformed\nh\xf0\x93\x8aXYZ";
+
+    let (x_index, _) = invalid_source
+        .iter()
+        .enumerate()
+        .find(|&(_, &x)| x == b'X')
+        .unwrap();
+
+    // make err pointing at the X
+    let err = E {
+        src: SourceSpan::from((x_index, 1)),
+    };
+
+    let result = fmt_report_with_settings(
+        Report::new(err.clone()).with_source_code(invalid_source),
+        |handler| handler,
+    );
+
+    let expected = "decode_err
+
+  × decoding error
+   ╭─[2:5]
+ 1 │ malformed
+ 2 │ h<EFBFBD>XYZ
+   ·   ┬
+   ·   ╰── valid data here
+   ╰────
+";
+
+    assert_eq!(expected, result);
+
+    let result = fmt_report_with_settings(
+        Report::new(err).with_source_code(invalid_source),
+        |handler| handler.without_primary_span_start(),
+    );
+
+    let expected = "decode_err
+
+  × decoding error
+   ╭────
+ 1 │ malformed
+ 2 │ h<EFBFBD>XYZ
+   ·   ┬
+   ·   ╰── valid data here
+   ╰────
+";
+
+    assert_eq!(expected, result);
+}