Softwrapping improvements (#5893)

* use max_line_width + 1 during softwrap to account for newline char

Helix softwrap implementation always wraps lines so that the newline
character doesn't get cut off so he line wraps one chars earlier then
in other editors. This is necessary, because newline chars are always
selecatble in helix and must never be hidden.

However That means that `max_line_width` currently wraps one char
earlier than expected. The typical definition of line width does not
include the newline character and other helix commands like `:reflow`
also don't count the newline character here.

This commit makes softwrap use `max_line_width + 1` instead of
`max_line_width` to correct the impedance missmatch.

* fix typos

Co-authored-by: Jonathan Lebon <jonathan@jlebon.com>

* Add text-width to config.toml

* text-width: update setting documentation

* rename leftover config item

* remove leftover max-line-length occurrences

* Make `text-width` optional in editor config

When it was only used for `:reflow` it made sense to have a default
value set to `80`, but now that soft-wrapping uses this setting, keeping
a default set to `80` would make soft-wrapping behave more aggressively.

* Allow softwrapping to ignore `text-width`

Softwrapping wraps by default to the viewport width or a configured
`text-width` (whichever's smaller). In some cases we only want to set
`text-width` to use for hard-wrapping and let longer lines flow if they
have enough space. This setting allows that.

* Revert "Make `text-width` optional in editor config"

This reverts commit b247d526d69adf41434b6fd9c4983369c785aa22.

* soft-wrap: allow per-language overrides

* Update book/src/configuration.md

Co-authored-by: Pascal Kuthe <pascal.kuthe@semimod.de>

* Update book/src/languages.md

Co-authored-by: Pascal Kuthe <pascal.kuthe@semimod.de>

* Update book/src/configuration.md

Co-authored-by: Pascal Kuthe <pascal.kuthe@semimod.de>

---------

Co-authored-by: Pascal Kuthe <pascal.kuthe@semimod.de>
Co-authored-by: Jonathan Lebon <jonathan@jlebon.com>
Co-authored-by: Alex Boehm <alexb@ozrunways.com>
Co-authored-by: Blaž Hrastnik <blaz@mxxn.io>

1 files changed, 8 insertions, 12 deletions

diff --git a/helix-term/src/commands/typed.rs b/helix-term/src/commands/typed.rs
index 7588b708..5ea61108 100644
--- a/helix-term/src/commands/typed.rs
+++ b/helix-term/src/commands/typed.rs
@@ -1840,30 +1840,26 @@ fn reflow(
     }
 
     let scrolloff = cx.editor.config().scrolloff;
+    let cfg_text_width: usize = cx.editor.config().text_width;
     let (view, doc) = current!(cx.editor);
 
-    const DEFAULT_MAX_LEN: usize = 79;
-
-    // Find the max line length by checking the following sources in order:
+    // Find the text_width by checking the following sources in order:
     //   - The passed argument in `args`
-    //   - The configured max_line_len for this language in languages.toml
-    //   - The const default we set above
-    let max_line_len: usize = args
+    //   - The configured text-width for this language in languages.toml
+    //   - The configured text-width in the config.toml
+    let text_width: usize = args
         .get(0)
         .map(|num| num.parse::<usize>())
         .transpose()?
-        .or_else(|| {
-            doc.language_config()
-                .and_then(|config| config.max_line_length)
-        })
-        .unwrap_or(DEFAULT_MAX_LEN);
+        .or_else(|| doc.language_config().and_then(|config| config.text_width))
+        .unwrap_or(cfg_text_width);
 
     let rope = doc.text();
 
     let selection = doc.selection(view.id);
     let transaction = Transaction::change_by_selection(rope, selection, |range| {
         let fragment = range.fragment(rope.slice(..));
-        let reflowed_text = helix_core::wrap::reflow_hard_wrap(&fragment, max_line_len);
+        let reflowed_text = helix_core::wrap::reflow_hard_wrap(&fragment, text_width);
 
         (range.from(), range.to(), Some(reflowed_text))
     });