46fe8c4da5
Add calculate_pages function that splits text into page boundaries by character offset. Includes tests for empty, single-page, multi-page, and zero-chars-per-page edge cases.
65 lines
1.4 KiB
Rust
65 lines
1.4 KiB
Rust
pub fn calculate_pages(text: &str, chars_per_page: usize) -> Vec<usize> {
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let mut pages = Vec::new();
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pages.push(0);
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if text.is_empty() || chars_per_page == 0 {
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return pages;
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}
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let total_chars = text.chars().count();
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if total_chars <= chars_per_page {
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pages.push(total_chars);
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return pages;
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}
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let mut pos = 0;
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while pos < total_chars {
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pos = (pos + chars_per_page).min(total_chars);
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pages.push(pos);
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}
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pages
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}
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#[cfg(test)]
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mod tests {
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use super::*;
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#[test]
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fn test_pagination_empty() {
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let pages = calculate_pages("", 100);
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assert_eq!(pages, vec![0]);
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}
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#[test]
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fn test_pagination_shorter_than_page() {
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let pages = calculate_pages("Hello World", 100);
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assert_eq!(pages, vec![0, 11]);
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}
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#[test]
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fn test_pagination_exact_fit() {
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let pages = calculate_pages("ABCD", 4);
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assert_eq!(pages, vec![0, 4]);
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}
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#[test]
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fn test_pagination_multiple_pages() {
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let text = "A".repeat(100);
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let pages = calculate_pages(&text, 30);
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assert_eq!(pages, vec![0, 30, 60, 90, 100]);
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}
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#[test]
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fn test_pagination_single_char() {
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let pages = calculate_pages("A", 1);
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assert_eq!(pages, vec![0, 1]);
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}
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#[test]
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fn test_pagination_zero_chars_per_page() {
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let pages = calculate_pages("test", 0);
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assert_eq!(pages, vec![0]);
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}
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}
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