From d0791e0f981a64b0c382c022ff79b0376cc09962 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bla=C5=BE=20Hrastnik?= Date: Thu, 18 Feb 2021 18:35:39 +0900 Subject: [PATCH] core: Implement comment toggling module. --- helix-core/src/comment.rs | 105 ++++++++++++++++++++++++++++++++++++++ helix-core/src/lib.rs | 1 + 2 files changed, 106 insertions(+) create mode 100644 helix-core/src/comment.rs diff --git a/helix-core/src/comment.rs b/helix-core/src/comment.rs new file mode 100644 index 00000000..87becfa3 --- /dev/null +++ b/helix-core/src/comment.rs @@ -0,0 +1,105 @@ +use crate::{find_first_non_whitespace_char2, Change, RopeSlice, State, Transaction}; +use core::ops::Range; +use std::borrow::Cow; + +fn find_line_comment( + token: &str, + text: RopeSlice, + lines: Range, +) -> (bool, Vec, usize) { + // selection ranges map char_to_line from() .. to() + let mut commented = true; + let mut skipped = Vec::new(); + let mut min = usize::MAX; // minimum col for find_first_non_whitespace_char + for line in lines { + let line_slice = text.line(line); + if let Some(pos) = find_first_non_whitespace_char2(line_slice) { + let len = line_slice.len_chars(); + + if pos < min { + min = pos; + } + + // line can be shorter than pos + token len + let fragment = Cow::from(line_slice.slice(pos..std::cmp::min(pos + token.len(), len))); + + if fragment != token { + // as soon as one of the non-blank lines doesn't have a comment, the whole block is + // considered uncommented. + commented = false; + } + } else { + // blank line + skipped.push(line); + } + } + (commented, skipped, min) +} + +fn toggle_line_comments(state: &State) -> Transaction { + let text = state.doc.slice(..); + let mut changes: Vec = Vec::new(); + + let token = "//"; + + for selection in state.selection.ranges() { + let start = text.char_to_line(selection.from()); + let end = text.char_to_line(selection.to()); + let lines = start..end + 1; + let (commented, skipped, min) = find_line_comment(token, text, lines.clone()); + + changes.reserve(end - start - skipped.len()); + + for line in lines { + if skipped.contains(&line) { + continue; + } + + let pos = text.line_to_char(line) + min; + + if !commented { + // comment line + changes.push((pos, pos, Some(format!("{} ", token).into()))) + } else { + // uncomment line + let margin = 1; // TODO: margin is hardcoded 1 but could easily be 0 + changes.push((pos, pos + token.len() + margin, None)) + } + } + } + Transaction::change(state, changes.into_iter()) +} + +#[cfg(test)] +mod test { + use super::*; + + #[test] + fn test_find_line_comment() { + use crate::{Rope, Selection}; + + // four lines, two space indented, except for line 1 which is blank. + let doc = Rope::from(" 1\n\n 2\n 3"); + + let mut state = State::new(doc); + // select whole document + state.selection = Selection::single(0, state.doc.len_chars() - 1); + + let text = state.doc.slice(..); + + let res = find_line_comment("//", text, 0..3); + // (commented = true, skipped = [line 1], min = col 2) + assert_eq!(res, (false, vec![1], 2)); + + // comment + let transaction = toggle_line_comments(&state); + transaction.apply(&mut state); + + assert_eq!(state.doc, " // 1\n\n // 2\n // 3"); + + // uncomment + let transaction = toggle_line_comments(&state); + transaction.apply(&mut state); + assert_eq!(state.doc, " 1\n\n 2\n 3"); + } +} diff --git a/helix-core/src/lib.rs b/helix-core/src/lib.rs index f9fe4bd4..977129ef 100644 --- a/helix-core/src/lib.rs +++ b/helix-core/src/lib.rs @@ -1,4 +1,5 @@ #![allow(unused)] +pub mod comment; mod diagnostic; pub mod graphemes; mod history;