Handle single-line comment prefixes in :reflow.

helix-core/src/doc_formatter.rs

@@ -23,6 +23,7 @@ use crate::graphemes::{Grapheme, GraphemeStr};
 use crate::syntax::Highlight;
 use crate::text_annotations::TextAnnotations;
 use crate::{movement, Change, LineEnding, Position, Rope, RopeGraphemes, RopeSlice, Tendril};
+use helix_stdx::rope::RopeSliceExt;
 
 /// TODO make Highlight a u32 to reduce the size of this enum to a single word.
 #[derive(Debug, Clone, Copy)]
@@ -150,6 +151,7 @@ pub struct TextFormat {
     pub wrap_indicator_highlight: Option<Highlight>,
     pub viewport_width: u16,
     pub soft_wrap_at_text_width: bool,
+    pub continue_comments: Vec<String>,
 }
 
 // test implementation is basically only used for testing or when softwrap is always disabled
@@ -164,6 +166,7 @@ impl Default for TextFormat {
             viewport_width: 17,
             wrap_indicator_highlight: None,
             soft_wrap_at_text_width: false,
+            continue_comments: Vec::new(),
         }
     }
 }
@@ -434,8 +437,18 @@ impl<'t> DocumentFormatter<'t> {
 
     fn find_indent<'a>(&self, line: usize, doc: RopeSlice<'a>) -> RopeSlice<'a> {
         let line_start = doc.line_to_char(line);
-        let indent_end = movement::skip_while(doc, line_start, |ch| matches!(ch, ' ' | '\t'))
+        let mut indent_end = movement::skip_while(doc, line_start, |ch| matches!(ch, ' ' | '\t'))
             .unwrap_or(line_start);
+        let slice = doc.slice(indent_end..);
+        if let Some(token) = self
+            .text_fmt
+            .continue_comments
+            .iter()
+            .filter(|token| slice.starts_with(token))
+            .max_by_key(|x| x.len())
+        {
+            indent_end += token.chars().count();
+        }
         let indent_end = movement::skip_while(doc, indent_end, |ch| matches!(ch, ' ' | '\t'))
             .unwrap_or(indent_end);
         return doc.slice(line_start..indent_end);

helix-core/src/doc_formatter/test.rs

@@ -13,6 +13,7 @@ impl TextFormat {
             // use a prime number to allow lining up too often with repeat
             viewport_width: 17,
             soft_wrap_at_text_width: false,
+            continue_comments: Vec::new(),
         }
     }
 }

helix-term/src/commands/typed.rs

@@ -2142,6 +2142,11 @@ fn reflow(
         wrap_indicator_highlight: None,
         viewport_width: u16::try_from(text_width).unwrap_or(u16::MAX),
         soft_wrap_at_text_width: true,
+        continue_comments: Vec::from(
+            doc.language_config()
+                .and_then(|config| config.comment_tokens.as_deref())
+                .unwrap_or(&[]),
+        ),
     };
     let annotations = TextAnnotations::default();
 

helix-term/tests/test/commands.rs

@@ -781,6 +781,61 @@ bla]#",
     ))
     .await?;
 
+    test((
+        "// #[|This is a really long comment that we want to break onto multiple lines.]#",
+        ":lang rust<ret>:reflow 13<ret>",
+        "// #[|This is a
+// really long
+// comment that
+// we want to
+// break onto
+// multiple
+// lines.]#",
+    ))
+    .await?;
+
+    test((
+        "#[\t// Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod
+\t// tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim
+\t// veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea
+\t// commodo consequat. Duis aute irure dolor in reprehenderit in voluptate
+\t// velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint
+\t// occaecat cupidatat non proident, sunt in culpa qui officia deserunt
+\t// mollit anim id est laborum.
+|]#",
+        ":lang go<ret>:reflow 50<ret>",
+        "#[\t// Lorem ipsum dolor sit amet,
+\t// consectetur adipiscing elit, sed do
+\t// eiusmod
+\t// tempor incididunt ut labore et dolore
+\t// magna aliqua. Ut enim ad minim
+\t// veniam, quis nostrud exercitation
+\t// ullamco laboris nisi ut aliquip ex ea
+\t// commodo consequat. Duis aute irure
+\t// dolor in reprehenderit in voluptate
+\t// velit esse cillum dolore eu fugiat
+\t// nulla pariatur. Excepteur sint
+\t// occaecat cupidatat non proident, sunt
+\t// in culpa qui officia deserunt
+\t// mollit anim id est laborum.
+|]#",
+    ))
+    .await?;
+
+    test((
+        "    // #[|This document has multiple lines that each need wrapping
+
+    /// currently we wrap each line completely separately in order to preserve existing newlines.]#",
+        ":lang rust<ret>:reflow 40<ret>",
+        "    // #[|This document has multiple lines
+    // that each need wrapping
+
+    /// currently we wrap each line
+    /// completely separately in order to
+    /// preserve existing newlines.]#"
+    ))
+    .await?;
+
     test((
         "#[|Very_long_words_should_not_be_broken_by_hard_wrap]#",
         ":reflow 2<ret>",

helix-view/src/annotations/diagnostics.rs

@@ -102,6 +102,7 @@ impl InlineDiagnosticsConfig {
             wrap_indicator_highlight: None,
             viewport_width: width,
             soft_wrap_at_text_width: true,
+            continue_comments: Vec::new(),
         }
     }
 }

helix-view/src/document.rs

@@ -2145,6 +2145,7 @@ impl Document {
                 .and_then(|theme| theme.find_scope_index("ui.virtual.wrap"))
                 .map(Highlight),
             soft_wrap_at_text_width,
+            continue_comments: Vec::new(),
         }
     }