Diff a string for presentation to a user in the terminal.
use termdiff::{SignsTheme, DrawDiff};
let old = "The quick brown fox and\njumps over the sleepy dog";
let new = "The quick red fox and\njumps over the lazy dog";
let theme = SignsTheme::default();
let actual = format!("{}", DrawDiff::new(old, new, &theme));
assert_eq!(
actual,
"--- remove | insert +++
-The quick brown fox and
-jumps over the sleepy dog
+The quick red fox and
+jumps over the lazy dog
"
);
Alternatively you can use this interface
use termdiff::{ArrowsTheme, diff};
let old = "The quick brown fox and\njumps over the sleepy dog";
let new = "The quick red fox and\njumps over the lazy dog";
let theme = ArrowsTheme::default();
let mut buffer: Vec<u8> = Vec::new();
diff(&mut buffer, old, new, &theme).unwrap();
let actual: String = String::from_utf8(buffer).expect("Not valid UTF-8");
assert_eq!(
actual,
"< left / > right
<The quick brown fox and
<jumps over the sleepy dog
>The quick red fox and
>jumps over the lazy dog
"
);
Read more at Docs.rs
We have a limited number of built in themes
use termdiff::DrawDiff;
use termdiff::Theme;
use crossterm::style::Stylize;
use std::borrow::Cow;
#[derive(Debug)]
struct MyTheme {}
impl Theme for MyTheme {
fn highlight_insert<'this>(&self, input: &'this str) -> Cow<'this, str> {
input.into()
}
fn highlight_delete<'this>(&self, input: &'this str) -> Cow<'this, str> {
input.into()
}
fn equal_content<'this>(&self, input: &'this str) -> Cow<'this, str> {
input.into()
}
fn delete_content<'this>(&self, input: &'this str) -> Cow<'this, str> {
input.into()
}
fn equal_prefix<'this>(&self) -> Cow<'this, str> {
"=".into()
}
fn delete_prefix<'this>(&self) -> Cow<'this, str> {
"!".into()
}
fn insert_line<'this>(&self, input: &'this str) -> Cow<'this, str> {
input.into()
}
fn insert_prefix<'this>(&self) -> Cow<'this, str> {
"|".into()
}
fn line_end<'this>(&self) -> Cow<'this, str> {
"\n".into()
}
fn header<'this>(&self) -> Cow<'this, str> {
format!("{}\n", "Header").into()
}
}
let my_theme = MyTheme {};
let old = "The quick brown fox and\njumps over the sleepy dog";
let new = "The quick red fox and\njumps over the lazy dog";
let actual = format!("{}", DrawDiff::new(old, new, &my_theme));
assert_eq!(
actual,
"Header
!The quick brown fox and
!jumps over the sleepy dog
|The quick red fox and
|jumps over the lazy dog
"
);