Add Increment trait

helix-core/src/increment/date.rs

@@ -0,0 +1,474 @@
+use regex::Regex;
+
+use std::borrow::Cow;
+use std::cmp;
+
+use ropey::RopeSlice;
+
+use crate::{Range, Tendril};
+
+use chrono::{Datelike, Duration, NaiveDate};
+
+use super::Increment;
+
+fn ndays_in_month(year: i32, month: u32) -> u32 {
+    // The first day of the next month...
+    let (y, m) = if month == 12 {
+        (year + 1, 1)
+    } else {
+        (year, month + 1)
+    };
+    let d = NaiveDate::from_ymd(y, m, 1);
+
+    // ...is preceded by the last day of the original month.
+    d.pred().day()
+}
+
+fn add_days(date: NaiveDate, amount: i64) -> Option<NaiveDate> {
+    date.checked_add_signed(Duration::days(amount))
+}
+
+fn add_months(date: NaiveDate, amount: i64) -> Option<NaiveDate> {
+    let month = date.month0() as i64 + amount;
+    let year = date.year() + i32::try_from(month / 12).ok()?;
+    let year = if month.is_negative() { year - 1 } else { year };
+
+    // Normalize month
+    let month = month % 12;
+    let month = if month.is_negative() {
+        month + 13
+    } else {
+        month + 1
+    } as u32;
+
+    let day = cmp::min(date.day(), ndays_in_month(year, month));
+
+    Some(NaiveDate::from_ymd(year, month, day))
+}
+
+fn add_years(date: NaiveDate, amount: i64) -> Option<NaiveDate> {
+    let year = i32::try_from(date.year() as i64 + amount).ok()?;
+    let ndays = ndays_in_month(year, date.month());
+
+    if date.day() > ndays {
+        let d = NaiveDate::from_ymd(year, date.month(), ndays);
+        Some(d.succ())
+    } else {
+        date.with_year(year)
+    }
+}
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+struct Format {
+    regex: &'static str,
+    separator: char,
+}
+
+// Only support formats that aren't region specific.
+static FORMATS: &[Format] = &[
+    Format {
+        regex: r"(\d{4})-(\d{2})-(\d{2})",
+        separator: '-',
+    },
+    Format {
+        regex: r"(\d{4})/(\d{2})/(\d{2})",
+        separator: '/',
+    },
+];
+
+const DATE_LENGTH: usize = 10;
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+enum DateField {
+    Year,
+    Month,
+    Day,
+}
+
+#[derive(Debug, PartialEq, Eq)]
+pub struct DateIncrementor {
+    date: NaiveDate,
+    range: Range,
+    field: DateField,
+    format: Format,
+}
+
+impl DateIncrementor {
+    pub fn from_range(text: RopeSlice, range: Range) -> Option<DateIncrementor> {
+        let range = if range.is_empty() {
+            if range.anchor < text.len_bytes() {
+                // Treat empty range as a cursor range.
+                range.put_cursor(text, range.anchor + 1, true)
+            } else {
+                // The range is empty and at the end of the text.
+                return None;
+            }
+        } else {
+            range
+        };
+
+        let from = range.from().saturating_sub(DATE_LENGTH);
+        let to = (range.from() + DATE_LENGTH).min(text.len_chars());
+
+        let (from_in_text, to_in_text) = (range.from() - from, range.to() - from);
+        let text: Cow<str> = text.slice(from..to).into();
+
+        FORMATS.iter().find_map(|&format| {
+            let re = Regex::new(format.regex).ok()?;
+            let captures = re.captures(&text)?;
+
+            let date = captures.get(0)?;
+            let offset = range.from() - from_in_text;
+            let range = Range::new(date.start() + offset, date.end() + offset);
+
+            let (year, month, day) = (captures.get(1)?, captures.get(2)?, captures.get(3)?);
+            let (year_range, month_range, day_range) = (year.range(), month.range(), day.range());
+
+            let field = if year_range.contains(&from_in_text)
+                && year_range.contains(&(to_in_text - 1))
+            {
+                DateField::Year
+            } else if month_range.contains(&from_in_text) && month_range.contains(&(to_in_text - 1))
+            {
+                DateField::Month
+            } else if day_range.contains(&from_in_text) && day_range.contains(&(to_in_text - 1)) {
+                DateField::Day
+            } else {
+                return None;
+            };
+
+            let date = NaiveDate::from_ymd_opt(
+                year.as_str().parse::<i32>().ok()?,
+                month.as_str().parse::<u32>().ok()?,
+                day.as_str().parse::<u32>().ok()?,
+            )?;
+
+            Some(DateIncrementor {
+                date,
+                field,
+                range,
+                format,
+            })
+        })
+    }
+}
+
+impl Increment for DateIncrementor {
+    fn increment(&self, amount: i64) -> (Range, Tendril) {
+        let date = match self.field {
+            DateField::Year => add_years(self.date, amount),
+            DateField::Month => add_months(self.date, amount),
+            DateField::Day => add_days(self.date, amount),
+        }
+        .unwrap_or(self.date);
+
+        (
+            self.range,
+            format!(
+                "{:04}{}{:02}{}{:02}",
+                date.year(),
+                self.format.separator,
+                date.month(),
+                self.format.separator,
+                date.day()
+            )
+            .into(),
+        )
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    use crate::Rope;
+
+    #[test]
+    fn test_create_incrementor_for_year_with_dashes() {
+        let rope = Rope::from_str("2021-11-15");
+
+        for cursor in 0..=3 {
+            let range = Range::new(cursor, cursor + 1);
+            assert_eq!(
+                DateIncrementor::from_range(rope.slice(..), range),
+                Some(DateIncrementor {
+                    date: NaiveDate::from_ymd(2021, 11, 15),
+                    range: Range::new(0, 10),
+                    field: DateField::Year,
+                    format: FORMATS[0],
+                })
+            );
+        }
+    }
+
+    #[test]
+    fn test_create_incrementor_for_month_with_dashes() {
+        let rope = Rope::from_str("2021-11-15");
+
+        for cursor in 5..=6 {
+            let range = Range::new(cursor, cursor + 1);
+            assert_eq!(
+                DateIncrementor::from_range(rope.slice(..), range),
+                Some(DateIncrementor {
+                    date: NaiveDate::from_ymd(2021, 11, 15),
+                    range: Range::new(0, 10),
+                    field: DateField::Month,
+                    format: FORMATS[0],
+                })
+            );
+        }
+    }
+
+    #[test]
+    fn test_create_incrementor_for_day_with_dashes() {
+        let rope = Rope::from_str("2021-11-15");
+
+        for cursor in 8..=9 {
+            let range = Range::new(cursor, cursor + 1);
+            assert_eq!(
+                DateIncrementor::from_range(rope.slice(..), range),
+                Some(DateIncrementor {
+                    date: NaiveDate::from_ymd(2021, 11, 15),
+                    range: Range::new(0, 10),
+                    field: DateField::Day,
+                    format: FORMATS[0],
+                })
+            );
+        }
+    }
+
+    #[test]
+    fn test_try_create_incrementor_on_dashes() {
+        let rope = Rope::from_str("2021-11-15");
+
+        for &cursor in &[4, 7] {
+            let range = Range::new(cursor, cursor + 1);
+            assert_eq!(DateIncrementor::from_range(rope.slice(..), range), None,);
+        }
+    }
+
+    #[test]
+    fn test_create_incrementor_for_year_with_slashes() {
+        let rope = Rope::from_str("2021/11/15");
+
+        for cursor in 0..=3 {
+            let range = Range::new(cursor, cursor + 1);
+            assert_eq!(
+                DateIncrementor::from_range(rope.slice(..), range),
+                Some(DateIncrementor {
+                    date: NaiveDate::from_ymd(2021, 11, 15),
+                    range: Range::new(0, 10),
+                    field: DateField::Year,
+                    format: FORMATS[1],
+                })
+            );
+        }
+    }
+
+    #[test]
+    fn test_create_incrementor_for_month_with_slashes() {
+        let rope = Rope::from_str("2021/11/15");
+
+        for cursor in 5..=6 {
+            let range = Range::new(cursor, cursor + 1);
+            assert_eq!(
+                DateIncrementor::from_range(rope.slice(..), range),
+                Some(DateIncrementor {
+                    date: NaiveDate::from_ymd(2021, 11, 15),
+                    range: Range::new(0, 10),
+                    field: DateField::Month,
+                    format: FORMATS[1],
+                })
+            );
+        }
+    }
+
+    #[test]
+    fn test_create_incrementor_for_day_with_slashes() {
+        let rope = Rope::from_str("2021/11/15");
+
+        for cursor in 8..=9 {
+            let range = Range::new(cursor, cursor + 1);
+            assert_eq!(
+                DateIncrementor::from_range(rope.slice(..), range),
+                Some(DateIncrementor {
+                    date: NaiveDate::from_ymd(2021, 11, 15),
+                    range: Range::new(0, 10),
+                    field: DateField::Day,
+                    format: FORMATS[1],
+                })
+            );
+        }
+    }
+
+    #[test]
+    fn test_try_create_incrementor_on_slashes() {
+        let rope = Rope::from_str("2021/11/15");
+
+        for &cursor in &[4, 7] {
+            let range = Range::new(cursor, cursor + 1);
+            assert_eq!(DateIncrementor::from_range(rope.slice(..), range), None,);
+        }
+    }
+
+    #[test]
+    fn test_date_surrounded_by_spaces() {
+        let rope = Rope::from_str("   2021-11-15  ");
+        let range = Range::new(3, 4);
+        assert_eq!(
+            DateIncrementor::from_range(rope.slice(..), range),
+            Some(DateIncrementor {
+                date: NaiveDate::from_ymd(2021, 11, 15),
+                range: Range::new(3, 13),
+                field: DateField::Year,
+                format: FORMATS[0],
+            })
+        );
+    }
+
+    #[test]
+    fn test_date_in_single_quotes() {
+        let rope = Rope::from_str("date = '2021-11-15'");
+        let range = Range::new(10, 11);
+        assert_eq!(
+            DateIncrementor::from_range(rope.slice(..), range),
+            Some(DateIncrementor {
+                date: NaiveDate::from_ymd(2021, 11, 15),
+                range: Range::new(8, 18),
+                field: DateField::Year,
+                format: FORMATS[0],
+            })
+        );
+    }
+
+    #[test]
+    fn test_date_in_double_quotes() {
+        let rope = Rope::from_str("let date = \"2021-11-15\";");
+        let range = Range::new(12, 13);
+        assert_eq!(
+            DateIncrementor::from_range(rope.slice(..), range),
+            Some(DateIncrementor {
+                date: NaiveDate::from_ymd(2021, 11, 15),
+                range: Range::new(12, 22),
+                field: DateField::Year,
+                format: FORMATS[0],
+            })
+        );
+    }
+
+    #[test]
+    fn test_date_cursor_one_right_of_date() {
+        let rope = Rope::from_str("2021-11-15 ");
+        let range = Range::new(10, 11);
+        assert_eq!(DateIncrementor::from_range(rope.slice(..), range), None);
+    }
+
+    #[test]
+    fn test_date_cursor_one_left_of_number() {
+        let rope = Rope::from_str(" 2021-11-15");
+        let range = Range::new(0, 1);
+        assert_eq!(DateIncrementor::from_range(rope.slice(..), range), None);
+    }
+
+    #[test]
+    fn test_date_empty_range_at_beginning() {
+        let rope = Rope::from_str("2021-11-15");
+        let range = Range::point(0);
+        assert_eq!(
+            DateIncrementor::from_range(rope.slice(..), range),
+            Some(DateIncrementor {
+                date: NaiveDate::from_ymd(2021, 11, 15),
+                range: Range::new(0, 10),
+                field: DateField::Year,
+                format: FORMATS[0],
+            })
+        );
+    }
+
+    #[test]
+    fn test_date_empty_range_at_in_middle() {
+        let rope = Rope::from_str("2021-11-15");
+        let range = Range::point(5);
+        assert_eq!(
+            DateIncrementor::from_range(rope.slice(..), range),
+            Some(DateIncrementor {
+                date: NaiveDate::from_ymd(2021, 11, 15),
+                range: Range::new(0, 10),
+                field: DateField::Month,
+                format: FORMATS[0],
+            })
+        );
+    }
+
+    #[test]
+    fn test_date_empty_range_at_end() {
+        let rope = Rope::from_str("2021-11-15");
+        let range = Range::point(10);
+        assert_eq!(DateIncrementor::from_range(rope.slice(..), range), None);
+    }
+
+    #[test]
+    fn test_invalid_dates() {
+        let tests = [
+            "0000-00-00",
+            "1980-2-21",
+            "1980-12-1",
+            "12345",
+            "2020-02-30",
+            "1999-12-32",
+            "19-12-32",
+            "1-2-3",
+            "0000/00/00",
+            "1980/2/21",
+            "1980/12/1",
+            "12345",
+            "2020/02/30",
+            "1999/12/32",
+            "19/12/32",
+            "1/2/3",
+        ];
+
+        for invalid in tests {
+            let rope = Rope::from_str(invalid);
+            let range = Range::new(0, 1);
+
+            assert_eq!(DateIncrementor::from_range(rope.slice(..), range), None);
+        }
+    }
+
+    #[test]
+    fn test_increment_dates() {
+        let tests = [
+            // (original, cursor, amount, expected)
+            ("2020-02-28", 0, 1, "2021-02-28"),
+            ("2020-02-29", 0, 1, "2021-03-01"),
+            ("2020-01-31", 5, 1, "2020-02-29"),
+            ("2020-01-20", 5, 1, "2020-02-20"),
+            ("2021-01-01", 5, -1, "2020-12-01"),
+            ("2021-01-31", 5, -2, "2020-11-30"),
+            ("2020-02-28", 8, 1, "2020-02-29"),
+            ("2021-02-28", 8, 1, "2021-03-01"),
+            ("2021-02-28", 0, -1, "2020-02-28"),
+            ("2021-03-01", 0, -1, "2020-03-01"),
+            ("2020-02-29", 5, -1, "2020-01-29"),
+            ("2020-02-20", 5, -1, "2020-01-20"),
+            ("2020-02-29", 8, -1, "2020-02-28"),
+            ("2021-03-01", 8, -1, "2021-02-28"),
+            ("1980/12/21", 8, 100, "1981/03/31"),
+            ("1980/12/21", 8, -100, "1980/09/12"),
+            ("1980/12/21", 8, 1000, "1983/09/17"),
+            ("1980/12/21", 8, -1000, "1978/03/27"),
+        ];
+
+        for (original, cursor, amount, expected) in tests {
+            let rope = Rope::from_str(original);
+            let range = Range::new(cursor, cursor + 1);
+            assert_eq!(
+                DateIncrementor::from_range(rope.slice(..), range)
+                    .unwrap()
+                    .increment(amount)
+                    .1,
+                expected.into()
+            );
+        }
+    }
+}

helix-core/src/increment/mod.rs

@@ -0,0 +1,8 @@
+pub mod date;
+pub mod number;
+
+use crate::{Range, Tendril};
+
+pub trait Increment {
+    fn increment(&self, amount: i64) -> (Range, Tendril);
+}

helix-core/src/increment/number.rs

@@ -0,0 +1,507 @@
+use std::borrow::Cow;
+
+use ropey::RopeSlice;
+
+use super::Increment;
+
+use crate::{
+    textobject::{textobject_word, TextObject},
+    Range, Tendril,
+};
+
+#[derive(Debug, PartialEq, Eq)]
+pub struct NumberIncrementor<'a> {
+    value: i64,
+    radix: u32,
+    range: Range,
+
+    text: RopeSlice<'a>,
+}
+
+impl<'a> NumberIncrementor<'a> {
+    /// Return information about number under rang if there is one.
+    pub fn from_range(text: RopeSlice, range: Range) -> Option<NumberIncrementor> {
+        // If the cursor is on the minus sign of a number we want to get the word textobject to the
+        // right of it.
+        let range = if range.to() < text.len_chars()
+            && range.to() - range.from() <= 1
+            && text.char(range.from()) == '-'
+        {
+            Range::new(range.from() + 1, range.to() + 1)
+        } else {
+            range
+        };
+
+        let range = textobject_word(text, range, TextObject::Inside, 1, false);
+
+        // If there is a minus sign to the left of the word object, we want to include it in the range.
+        let range = if range.from() > 0 && text.char(range.from() - 1) == '-' {
+            range.extend(range.from() - 1, range.from())
+        } else {
+            range
+        };
+
+        let word: String = text
+            .slice(range.from()..range.to())
+            .chars()
+            .filter(|&c| c != '_')
+            .collect();
+        let (radix, prefixed) = if word.starts_with("0x") {
+            (16, true)
+        } else if word.starts_with("0o") {
+            (8, true)
+        } else if word.starts_with("0b") {
+            (2, true)
+        } else {
+            (10, false)
+        };
+
+        let number = if prefixed { &word[2..] } else { &word };
+
+        let value = i128::from_str_radix(number, radix).ok()?;
+        if (value.is_positive() && value.leading_zeros() < 64)
+            || (value.is_negative() && value.leading_ones() < 64)
+        {
+            return None;
+        }
+
+        let value = value as i64;
+        Some(NumberIncrementor {
+            range,
+            value,
+            radix,
+            text,
+        })
+    }
+}
+
+impl<'a> Increment for NumberIncrementor<'a> {
+    fn increment(&self, amount: i64) -> (Range, Tendril) {
+        let old_text: Cow<str> = self.text.slice(self.range.from()..self.range.to()).into();
+        let old_length = old_text.len();
+        let new_value = self.value.wrapping_add(amount);
+
+        // Get separator indexes from right to left.
+        let separator_rtl_indexes: Vec<usize> = old_text
+            .chars()
+            .rev()
+            .enumerate()
+            .filter_map(|(i, c)| if c == '_' { Some(i) } else { None })
+            .collect();
+
+        let format_length = if self.radix == 10 {
+            match (self.value.is_negative(), new_value.is_negative()) {
+                (true, false) => old_length - 1,
+                (false, true) => old_length + 1,
+                _ => old_text.len(),
+            }
+        } else {
+            old_text.len() - 2
+        } - separator_rtl_indexes.len();
+
+        let mut new_text = match self.radix {
+            2 => format!("0b{:01$b}", new_value, format_length),
+            8 => format!("0o{:01$o}", new_value, format_length),
+            10 if old_text.starts_with('0') || old_text.starts_with("-0") => {
+                format!("{:01$}", new_value, format_length)
+            }
+            10 => format!("{}", new_value),
+            16 => {
+                let (lower_count, upper_count): (usize, usize) =
+                    old_text.chars().skip(2).fold((0, 0), |(lower, upper), c| {
+                        (
+                            lower + c.is_ascii_lowercase().then(|| 1).unwrap_or(0),
+                            upper + c.is_ascii_uppercase().then(|| 1).unwrap_or(0),
+                        )
+                    });
+                if upper_count > lower_count {
+                    format!("0x{:01$X}", new_value, format_length)
+                } else {
+                    format!("0x{:01$x}", new_value, format_length)
+                }
+            }
+            _ => unimplemented!("radix not supported: {}", self.radix),
+        };
+
+        // Add separators from original number.
+        for &rtl_index in &separator_rtl_indexes {
+            if rtl_index < new_text.len() {
+                let new_index = new_text.len() - rtl_index;
+                new_text.insert(new_index, '_');
+            }
+        }
+
+        // Add in additional separators if necessary.
+        if new_text.len() > old_length && !separator_rtl_indexes.is_empty() {
+            let spacing = match separator_rtl_indexes.as_slice() {
+                [.., b, a] => a - b - 1,
+                _ => separator_rtl_indexes[0],
+            };
+
+            let prefix_length = if self.radix == 10 { 0 } else { 2 };
+            if let Some(mut index) = new_text.find('_') {
+                while index - prefix_length > spacing {
+                    index -= spacing;
+                    new_text.insert(index, '_');
+                }
+            }
+        }
+
+        (self.range, new_text.into())
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    use crate::Rope;
+
+    #[test]
+    fn test_decimal_at_point() {
+        let rope = Rope::from_str("Test text 12345 more text.");
+        let range = Range::point(12);
+        assert_eq!(
+            NumberIncrementor::from_range(rope.slice(..), range),
+            Some(NumberIncrementor {
+                range: Range::new(10, 15),
+                value: 12345,
+                radix: 10,
+                text: rope.slice(..),
+            })
+        );
+    }
+
+    #[test]
+    fn test_uppercase_hexadecimal_at_point() {
+        let rope = Rope::from_str("Test text 0x123ABCDEF more text.");
+        let range = Range::point(12);
+        assert_eq!(
+            NumberIncrementor::from_range(rope.slice(..), range),
+            Some(NumberIncrementor {
+                range: Range::new(10, 21),
+                value: 0x123ABCDEF,
+                radix: 16,
+                text: rope.slice(..),
+            })
+        );
+    }
+
+    #[test]
+    fn test_lowercase_hexadecimal_at_point() {
+        let rope = Rope::from_str("Test text 0xfa3b4e more text.");
+        let range = Range::point(12);
+        assert_eq!(
+            NumberIncrementor::from_range(rope.slice(..), range),
+            Some(NumberIncrementor {
+                range: Range::new(10, 18),
+                value: 0xfa3b4e,
+                radix: 16,
+                text: rope.slice(..),
+            })
+        );
+    }
+
+    #[test]
+    fn test_octal_at_point() {
+        let rope = Rope::from_str("Test text 0o1074312 more text.");
+        let range = Range::point(12);
+        assert_eq!(
+            NumberIncrementor::from_range(rope.slice(..), range),
+            Some(NumberIncrementor {
+                range: Range::new(10, 19),
+                value: 0o1074312,
+                radix: 8,
+                text: rope.slice(..),
+            })
+        );
+    }
+
+    #[test]
+    fn test_binary_at_point() {
+        let rope = Rope::from_str("Test text 0b10111010010101 more text.");
+        let range = Range::point(12);
+        assert_eq!(
+            NumberIncrementor::from_range(rope.slice(..), range),
+            Some(NumberIncrementor {
+                range: Range::new(10, 26),
+                value: 0b10111010010101,
+                radix: 2,
+                text: rope.slice(..),
+            })
+        );
+    }
+
+    #[test]
+    fn test_negative_decimal_at_point() {
+        let rope = Rope::from_str("Test text -54321 more text.");
+        let range = Range::point(12);
+        assert_eq!(
+            NumberIncrementor::from_range(rope.slice(..), range),
+            Some(NumberIncrementor {
+                range: Range::new(10, 16),
+                value: -54321,
+                radix: 10,
+                text: rope.slice(..),
+            })
+        );
+    }
+
+    #[test]
+    fn test_decimal_with_leading_zeroes_at_point() {
+        let rope = Rope::from_str("Test text 000045326 more text.");
+        let range = Range::point(12);
+        assert_eq!(
+            NumberIncrementor::from_range(rope.slice(..), range),
+            Some(NumberIncrementor {
+                range: Range::new(10, 19),
+                value: 45326,
+                radix: 10,
+                text: rope.slice(..),
+            })
+        );
+    }
+
+    #[test]
+    fn test_negative_decimal_cursor_on_minus_sign() {
+        let rope = Rope::from_str("Test text -54321 more text.");
+        let range = Range::point(10);
+        assert_eq!(
+            NumberIncrementor::from_range(rope.slice(..), range),
+            Some(NumberIncrementor {
+                range: Range::new(10, 16),
+                value: -54321,
+                radix: 10,
+                text: rope.slice(..),
+            })
+        );
+    }
+
+    #[test]
+    fn test_number_under_range_start_of_rope() {
+        let rope = Rope::from_str("100");
+        let range = Range::point(0);
+        assert_eq!(
+            NumberIncrementor::from_range(rope.slice(..), range),
+            Some(NumberIncrementor {
+                range: Range::new(0, 3),
+                value: 100,
+                radix: 10,
+                text: rope.slice(..),
+            })
+        );
+    }
+
+    #[test]
+    fn test_number_under_range_end_of_rope() {
+        let rope = Rope::from_str("100");
+        let range = Range::point(2);
+        assert_eq!(
+            NumberIncrementor::from_range(rope.slice(..), range),
+            Some(NumberIncrementor {
+                range: Range::new(0, 3),
+                value: 100,
+                radix: 10,
+                text: rope.slice(..),
+            })
+        );
+    }
+
+    #[test]
+    fn test_number_surrounded_by_punctuation() {
+        let rope = Rope::from_str(",100;");
+        let range = Range::point(1);
+        assert_eq!(
+            NumberIncrementor::from_range(rope.slice(..), range),
+            Some(NumberIncrementor {
+                range: Range::new(1, 4),
+                value: 100,
+                radix: 10,
+                text: rope.slice(..),
+            })
+        );
+    }
+
+    #[test]
+    fn test_not_a_number_point() {
+        let rope = Rope::from_str("Test text 45326 more text.");
+        let range = Range::point(6);
+        assert_eq!(NumberIncrementor::from_range(rope.slice(..), range), None);
+    }
+
+    #[test]
+    fn test_number_too_large_at_point() {
+        let rope = Rope::from_str("Test text 0xFFFFFFFFFFFFFFFFF more text.");
+        let range = Range::point(12);
+        assert_eq!(NumberIncrementor::from_range(rope.slice(..), range), None);
+    }
+
+    #[test]
+    fn test_number_cursor_one_right_of_number() {
+        let rope = Rope::from_str("100 ");
+        let range = Range::point(3);
+        assert_eq!(NumberIncrementor::from_range(rope.slice(..), range), None);
+    }
+
+    #[test]
+    fn test_number_cursor_one_left_of_number() {
+        let rope = Rope::from_str(" 100");
+        let range = Range::point(0);
+        assert_eq!(NumberIncrementor::from_range(rope.slice(..), range), None);
+    }
+
+    #[test]
+    fn test_increment_basic_decimal_numbers() {
+        let tests = [
+            ("100", 1, "101"),
+            ("100", -1, "99"),
+            ("99", 1, "100"),
+            ("100", 1000, "1100"),
+            ("100", -1000, "-900"),
+            ("-1", 1, "0"),
+            ("-1", 2, "1"),
+            ("1", -1, "0"),
+            ("1", -2, "-1"),
+        ];
+
+        for (original, amount, expected) in tests {
+            let rope = Rope::from_str(original);
+            let range = Range::point(0);
+            assert_eq!(
+                NumberIncrementor::from_range(rope.slice(..), range)
+                    .unwrap()
+                    .increment(amount)
+                    .1,
+                expected.into()
+            );
+        }
+    }
+
+    #[test]
+    fn test_increment_basic_hexadedimal_numbers() {
+        let tests = [
+            ("0x0100", 1, "0x0101"),
+            ("0x0100", -1, "0x00ff"),
+            ("0x0001", -1, "0x0000"),
+            ("0x0000", -1, "0xffffffffffffffff"),
+            ("0xffffffffffffffff", 1, "0x0000000000000000"),
+            ("0xffffffffffffffff", 2, "0x0000000000000001"),
+            ("0xffffffffffffffff", -1, "0xfffffffffffffffe"),
+            ("0xABCDEF1234567890", 1, "0xABCDEF1234567891"),
+            ("0xabcdef1234567890", 1, "0xabcdef1234567891"),
+        ];
+
+        for (original, amount, expected) in tests {
+            let rope = Rope::from_str(original);
+            let range = Range::point(0);
+            assert_eq!(
+                NumberIncrementor::from_range(rope.slice(..), range)
+                    .unwrap()
+                    .increment(amount)
+                    .1,
+                expected.into()
+            );
+        }
+    }
+
+    #[test]
+    fn test_increment_basic_octal_numbers() {
+        let tests = [
+            ("0o0107", 1, "0o0110"),
+            ("0o0110", -1, "0o0107"),
+            ("0o0001", -1, "0o0000"),
+            ("0o7777", 1, "0o10000"),
+            ("0o1000", -1, "0o0777"),
+            ("0o0107", 10, "0o0121"),
+            ("0o0000", -1, "0o1777777777777777777777"),
+            ("0o1777777777777777777777", 1, "0o0000000000000000000000"),
+            ("0o1777777777777777777777", 2, "0o0000000000000000000001"),
+            ("0o1777777777777777777777", -1, "0o1777777777777777777776"),
+        ];
+
+        for (original, amount, expected) in tests {
+            let rope = Rope::from_str(original);
+            let range = Range::point(0);
+            assert_eq!(
+                NumberIncrementor::from_range(rope.slice(..), range)
+                    .unwrap()
+                    .increment(amount)
+                    .1,
+                expected.into()
+            );
+        }
+    }
+
+    #[test]
+    fn test_increment_basic_binary_numbers() {
+        let tests = [
+            ("0b00000100", 1, "0b00000101"),
+            ("0b00000100", -1, "0b00000011"),
+            ("0b00000100", 2, "0b00000110"),
+            ("0b00000100", -2, "0b00000010"),
+            ("0b00000001", -1, "0b00000000"),
+            ("0b00111111", 10, "0b01001001"),
+            ("0b11111111", 1, "0b100000000"),
+            ("0b10000000", -1, "0b01111111"),
+            (
+                "0b0000",
+                -1,
+                "0b1111111111111111111111111111111111111111111111111111111111111111",
+            ),
+            (
+                "0b1111111111111111111111111111111111111111111111111111111111111111",
+                1,
+                "0b0000000000000000000000000000000000000000000000000000000000000000",
+            ),
+            (
+                "0b1111111111111111111111111111111111111111111111111111111111111111",
+                2,
+                "0b0000000000000000000000000000000000000000000000000000000000000001",
+            ),
+            (
+                "0b1111111111111111111111111111111111111111111111111111111111111111",
+                -1,
+                "0b1111111111111111111111111111111111111111111111111111111111111110",
+            ),
+        ];
+
+        for (original, amount, expected) in tests {
+            let rope = Rope::from_str(original);
+            let range = Range::point(0);
+            assert_eq!(
+                NumberIncrementor::from_range(rope.slice(..), range)
+                    .unwrap()
+                    .increment(amount)
+                    .1,
+                expected.into()
+            );
+        }
+    }
+
+    #[test]
+    fn test_increment_with_separators() {
+        let tests = [
+            ("999_999", 1, "1_000_000"),
+            ("1_000_000", -1, "999_999"),
+            ("-999_999", -1, "-1_000_000"),
+            ("0x0000_0000_0001", 0x1_ffff_0000, "0x0001_ffff_0001"),
+            ("0x0000_0000_0001", 0x1_ffff_0000, "0x0001_ffff_0001"),
+            ("0x0000_0000_0001", 0x1_ffff_0000, "0x0001_ffff_0001"),
+            ("0x0000_0000", -1, "0xffff_ffff_ffff_ffff"),
+            ("0x0000_0000_0000", -1, "0xffff_ffff_ffff_ffff"),
+            ("0b01111111_11111111", 1, "0b10000000_00000000"),
+            ("0b11111111_11111111", 1, "0b1_00000000_00000000"),
+        ];
+
+        for (original, amount, expected) in tests {
+            let rope = Rope::from_str(original);
+            let range = Range::point(0);
+            assert_eq!(
+                NumberIncrementor::from_range(rope.slice(..), range)
+                    .unwrap()
+                    .increment(amount)
+                    .1,
+                expected.into()
+            );
+        }
+    }
+}