| 1 | //! Paste-burst handling — turn rapid keystrokes (terminals without bracketed |
| 2 | //! paste) into a single committed buffer instead of N individual chars. |
| 3 | //! |
| 4 | //! Extracted from `tui/ui.rs` (P1.2). The owning state machine lives on |
| 5 | //! `App.paste_burst` (`tui::paste_burst`); these helpers wire it to the key |
| 6 | //! event loop and the composer's text buffer. |
| 7 | |
| 8 | use std::time::Instant; |
| 9 | |
| 10 | use crossterm::event::{KeyCode, KeyEvent, KeyModifiers}; |
| 11 | |
| 12 | use super::app::{App, looks_like_slash_command_input}; |
| 13 | use super::paste_burst::CharDecision; |
| 14 | |
| 15 | /// Process a key in the context of paste-burst detection. Returns `true` |
| 16 | /// when the key was fully handled by the paste machinery (caller skips |
| 17 | /// further input handling); `false` when the key still needs the normal |
| 18 | /// composer path. |
| 19 | pub fn handle_paste_burst_key(app: &mut App, key: &KeyEvent, now: Instant) -> bool { |
| 20 | if !app.use_paste_burst_detection { |
| 21 | return false; |
| 22 | } |
| 23 | // Once we've observed a real `Event::Paste` in this session, bracketed |
| 24 | // paste is verified working and the rapid-keystroke heuristic is |
| 25 | // unnecessary. Skipping it eliminates false positives on fast typing / |
| 26 | // IME commits / autocomplete on terminals with reliable bracketed |
| 27 | // paste (the dominant case on iTerm2 / Ghostty / WezTerm / Windows |
| 28 | // Terminal). |
| 29 | if app.bracketed_paste_seen { |
| 30 | return false; |
| 31 | } |
| 32 | |
| 33 | let has_ctrl_alt_or_super = key.modifiers.contains(KeyModifiers::CONTROL) |
| 34 | || key.modifiers.contains(KeyModifiers::ALT) |
| 35 | || key.modifiers.contains(KeyModifiers::SUPER); |
| 36 | |
| 37 | match key.code { |
| 38 | KeyCode::Enter => { |
| 39 | if !in_command_context(app) && app.paste_burst.append_newline_if_active(now) { |
| 40 | return true; |
| 41 | } |
| 42 | if !in_command_context(app) |
| 43 | && app.paste_burst.newline_should_insert_instead_of_submit(now) |
| 44 | { |
| 45 | app.insert_char('\n'); |
| 46 | // Deliberately no `extend_window` here. This Enter arrived |
| 47 | // with no burst being assembled, so it is only *maybe* a |
| 48 | // pasted newline. Re-arming on that guess let each absorbed |
| 49 | // Enter buy another 120ms, so a user pressing Enter to send |
| 50 | // never submitted — every press just added a newline. The |
| 51 | // window now always expires 120ms after the last real |
| 52 | // keystroke; newlines genuinely inside a paste are absorbed |
| 53 | // by `append_newline_if_active` above, which does re-arm. |
| 54 | return true; |
| 55 | } |
| 56 | } |
| 57 | KeyCode::Char(c) if !has_ctrl_alt_or_super => { |
| 58 | if !c.is_ascii() { |
| 59 | // IME-committed characters (Chinese, Japanese, Korean) |
| 60 | // arrive as individual KeyCode::Char events, typically with |
| 61 | // tens-of-milliseconds gaps between each committed character. |
| 62 | // Paste-burst buffering would lose characters when the IME |
| 63 | // commits slower than the burst heuristic's timing window. |
| 64 | // |
| 65 | // We still call note_plain_char + arm the suppression window |
| 66 | // so that: |
| 67 | // 1. The burst timing counter advances for non-IME fast |
| 68 | // typing on terminals without bracketed paste support. |
| 69 | // 2. The Enter-suppression window stays open during a rapid |
| 70 | // non-ASCII sequence, preventing premature submission. |
| 71 | // But the character is inserted directly into the composer |
| 72 | // rather than placed into the paste-burst buffer. |
| 73 | // |
| 74 | // The window is sized by how fast the characters are |
| 75 | // arriving: a lone IME candidate commit is ordinary typing |
| 76 | // and must not swallow the Enter that follows it, while a |
| 77 | // run of characters at paste speed keeps the full window. |
| 78 | // See `PasteBurst::arm_window_for_direct_char`. |
| 79 | if let Some(pending) = app.paste_burst.flush_before_modified_input() { |
| 80 | app.insert_str(&pending); |
| 81 | } |
| 82 | let rapid_chars = app.paste_burst.note_plain_char(now); |
| 83 | app.paste_burst.arm_window_for_direct_char(now, rapid_chars); |
| 84 | app.insert_char(c); |
| 85 | return true; |
| 86 | } |
| 87 | |
| 88 | let decision = app.paste_burst.on_plain_char(c, now); |
| 89 | return handle_paste_burst_decision(app, decision, c, now); |
| 90 | } |
| 91 | _ => {} |
| 92 | } |
| 93 | |
| 94 | false |
| 95 | } |
| 96 | |
| 97 | /// Apply a paste-burst decision to the composer buffer. Some decisions |
| 98 | /// retroactively grab the last few chars from the input back into the |
| 99 | /// pending paste buffer (when the heuristic decides the recent typing was |
| 100 | /// actually a paste). |
| 101 | pub fn handle_paste_burst_decision( |
| 102 | app: &mut App, |
| 103 | decision: CharDecision, |
| 104 | c: char, |
| 105 | now: Instant, |
| 106 | ) -> bool { |
| 107 | match decision { |
| 108 | CharDecision::RetainFirstChar => true, |
| 109 | CharDecision::BeginBufferFromPending | CharDecision::BufferAppend => { |
| 110 | app.paste_burst.append_char_to_buffer(c, now); |
| 111 | true |
| 112 | } |
| 113 | CharDecision::BeginBuffer { retro_chars } => { |
| 114 | if apply_paste_burst_retro_capture(app, retro_chars as usize, c, now) { |
| 115 | return true; |
| 116 | } |
| 117 | app.insert_char(c); |
| 118 | true |
| 119 | } |
| 120 | } |
| 121 | } |
| 122 | |
| 123 | fn apply_paste_burst_retro_capture( |
| 124 | app: &mut App, |
| 125 | retro_chars: usize, |
| 126 | c: char, |
| 127 | now: Instant, |
| 128 | ) -> bool { |
| 129 | let cursor_byte = app.cursor_byte_index(); |
| 130 | let before = &app.composer.input[..cursor_byte]; |
| 131 | let Some(grab) = app |
| 132 | .composer |
| 133 | .paste_burst |
| 134 | .decide_begin_buffer(now, before, retro_chars) |
| 135 | else { |
| 136 | return false; |
| 137 | }; |
| 138 | if !grab.grabbed.is_empty() { |
| 139 | app.input.replace_range(grab.start_byte..cursor_byte, ""); |
| 140 | let removed = grab.grabbed.chars().count(); |
| 141 | app.cursor_position = app.cursor_position.saturating_sub(removed); |
| 142 | } |
| 143 | app.paste_burst.append_char_to_buffer(c, now); |
| 144 | true |
| 145 | } |
| 146 | |
| 147 | fn in_command_context(app: &App) -> bool { |
| 148 | looks_like_slash_command_input(&app.input) |
| 149 | } |
| 150 | |
| 151 | #[cfg(test)] |
| 152 | mod tests { |
| 153 | use super::*; |
| 154 | use crate::config::Config; |
| 155 | use crate::tui::app::TuiOptions; |
| 156 | use crossterm::event::{KeyCode, KeyEvent, KeyModifiers}; |
| 157 | use std::path::PathBuf; |
| 158 | use std::time::{Duration, Instant}; |
| 159 | |
| 160 | fn test_app() -> App { |
| 161 | let options = TuiOptions { |
| 162 | ..crate::test_support::test_tui_options(PathBuf::from(".")) |
| 163 | }; |
| 164 | let mut app = App::new(options, &Config::default()); |
| 165 | app.use_paste_burst_detection = true; |
| 166 | app |
| 167 | } |
| 168 | |
| 169 | fn plain(ch: char) -> KeyEvent { |
| 170 | KeyEvent::new(KeyCode::Char(ch), KeyModifiers::NONE) |
| 171 | } |
| 172 | |
| 173 | #[test] |
| 174 | fn raw_short_cjk_multiline_paste_buffers_enter_instead_of_submitting() { |
| 175 | // #1302: pasting short CJK content like "请联网搜索：\nSTM32 …" used |
| 176 | // to silently submit the first line because the heuristic decided |
| 177 | // it wasn't paste-like (no whitespace + under 16 chars). The |
| 178 | // non-ASCII bypass now classifies it as a paste so the Enter is |
| 179 | // absorbed into the burst buffer. |
| 180 | let mut app = test_app(); |
| 181 | let t0 = Instant::now(); |
| 182 | |
| 183 | let pasted = "请联网搜索：\nSTM32 商业应用案例"; |
| 184 | for (i, ch) in pasted.chars().enumerate() { |
| 185 | let key = if ch == '\n' { |
| 186 | KeyEvent::new(KeyCode::Enter, KeyModifiers::NONE) |
| 187 | } else { |
| 188 | plain(ch) |
| 189 | }; |
| 190 | let handled = |
| 191 | handle_paste_burst_key(&mut app, &key, t0 + Duration::from_millis(i as u64)); |
| 192 | assert!( |
| 193 | handled, |
| 194 | "raw paste character {ch:?} must be handled by paste-burst detection" |
| 195 | ); |
| 196 | } |
| 197 | |
| 198 | // Non-ASCII characters are now inserted directly into the composer |
| 199 | // rather than buffered by paste burst. The Enter suppression window |
| 200 | // kept the newline from submitting prematurely. |
| 201 | assert_eq!(app.input, pasted); |
| 202 | } |
| 203 | |
| 204 | #[test] |
| 205 | fn raw_multiline_paste_buffers_enter_instead_of_submitting() { |
| 206 | let mut app = test_app(); |
| 207 | let t0 = Instant::now(); |
| 208 | |
| 209 | assert!(handle_paste_burst_key(&mut app, &plain('a'), t0)); |
| 210 | assert!(handle_paste_burst_key( |
| 211 | &mut app, |
| 212 | &plain('b'), |
| 213 | t0 + Duration::from_millis(1) |
| 214 | )); |
| 215 | assert!(handle_paste_burst_key( |
| 216 | &mut app, |
| 217 | &plain('c'), |
| 218 | t0 + Duration::from_millis(2) |
| 219 | )); |
| 220 | assert!(handle_paste_burst_key( |
| 221 | &mut app, |
| 222 | &KeyEvent::new(KeyCode::Enter, KeyModifiers::NONE), |
| 223 | t0 + Duration::from_millis(3) |
| 224 | )); |
| 225 | |
| 226 | assert!(app.input.is_empty(), "paste remains buffered until idle"); |
| 227 | assert!(app.flush_paste_burst_if_due( |
| 228 | t0 + Duration::from_millis(3) |
| 229 | + crate::tui::paste_burst::PasteBurst::recommended_active_flush_delay() |
| 230 | )); |
| 231 | assert_eq!(app.input, "abc\n"); |
| 232 | } |
| 233 | |
| 234 | /// A raw CJK paste can open with a one-character line |
| 235 | /// ("好\n…"). That single character never forms a paste-speed *run*, so |
| 236 | /// the short window is all that protects the embedded newline — the |
| 237 | /// newline arrives within the burst interval, so it must still be |
| 238 | /// absorbed rather than submitting "好" on its own (#1302). |
| 239 | #[test] |
| 240 | fn raw_paste_with_single_char_first_line_still_absorbs_its_newline() { |
| 241 | let mut app = test_app(); |
| 242 | let t0 = Instant::now(); |
| 243 | |
| 244 | assert!(handle_paste_burst_key(&mut app, &plain('好'), t0)); |
| 245 | assert!( |
| 246 | handle_paste_burst_key( |
| 247 | &mut app, |
| 248 | &KeyEvent::new(KeyCode::Enter, KeyModifiers::NONE), |
| 249 | t0 + Duration::from_millis(1), |
| 250 | ), |
| 251 | "the newline of a raw paste lands within the burst interval and \ |
| 252 | must be absorbed, not submitted" |
| 253 | ); |
| 254 | assert_eq!(app.input, "好\n"); |
| 255 | } |
| 256 | |
| 257 | /// The IME half of the same ambiguity: one committed character followed |
| 258 | /// by a human-speed Enter is a send gesture. `handle_paste_burst_key` |
| 259 | /// must decline the Enter so it reaches the normal submit path. |
| 260 | #[test] |
| 261 | fn ime_commit_then_human_enter_falls_through_to_submit() { |
| 262 | let mut app = test_app(); |
| 263 | let t0 = Instant::now(); |
| 264 | |
| 265 | assert!(handle_paste_burst_key(&mut app, &plain('好'), t0)); |
| 266 | assert_eq!(app.input, "好"); |
| 267 | |
| 268 | assert!( |
| 269 | !handle_paste_burst_key( |
| 270 | &mut app, |
| 271 | &KeyEvent::new(KeyCode::Enter, KeyModifiers::NONE), |
| 272 | t0 + Duration::from_millis(30), |
| 273 | ), |
| 274 | "Enter 30ms after an IME candidate commit is a send, not a \ |
| 275 | pasted newline" |
| 276 | ); |
| 277 | assert_eq!(app.input, "好", "no stray newline may be inserted"); |
| 278 | } |
| 279 | |
| 280 | /// A whole IME-typed CJK sentence, one commit at a time at human speed, |
| 281 | /// followed by Enter: every character lands verbatim and the Enter still |
| 282 | /// reaches the submit path. |
| 283 | #[test] |
| 284 | fn ime_typed_sentence_then_enter_falls_through_to_submit() { |
| 285 | let mut app = test_app(); |
| 286 | let t0 = Instant::now(); |
| 287 | |
| 288 | for (i, ch) in "你好世界".chars().enumerate() { |
| 289 | let now = t0 + Duration::from_millis(50 * i as u64); |
| 290 | assert!(handle_paste_burst_key(&mut app, &plain(ch), now)); |
| 291 | } |
| 292 | assert_eq!(app.input, "你好世界"); |
| 293 | |
| 294 | assert!( |
| 295 | !handle_paste_burst_key( |
| 296 | &mut app, |
| 297 | &KeyEvent::new(KeyCode::Enter, KeyModifiers::NONE), |
| 298 | t0 + Duration::from_millis(180), |
| 299 | ), |
| 300 | "Enter after an IME-typed CJK message must submit" |
| 301 | ); |
| 302 | assert_eq!(app.input, "你好世界"); |
| 303 | } |
| 304 | |
| 305 | /// Absorbing an Enter outside an active burst must not re-arm the |
| 306 | /// suppression window. It used to, so each swallowed Enter bought |
| 307 | /// another 120ms and a user pressing Enter to send only ever added |
| 308 | /// newlines. The first Enter is still absorbed (#1073 trailing-newline |
| 309 | /// protection); the next one submits. |
| 310 | #[test] |
| 311 | fn absorbed_enter_does_not_extend_the_suppression_window() { |
| 312 | let mut app = test_app(); |
| 313 | let t0 = Instant::now(); |
| 314 | |
| 315 | // Unbracketed paste of "abc" with no trailing newline. |
| 316 | for (i, ch) in "abc".chars().enumerate() { |
| 317 | let now = t0 + Duration::from_millis(i as u64); |
| 318 | assert!(handle_paste_burst_key(&mut app, &plain(ch), now)); |
| 319 | } |
| 320 | let last_char = t0 + Duration::from_millis(2); |
| 321 | assert!(app.flush_paste_burst_if_due( |
| 322 | last_char + crate::tui::paste_burst::PasteBurst::recommended_active_flush_delay() |
| 323 | )); |
| 324 | assert_eq!(app.input, "abc"); |
| 325 | |
| 326 | // Still inside the window: this could be the paste's trailing |
| 327 | // newline, so it is absorbed. |
| 328 | assert!(handle_paste_burst_key( |
| 329 | &mut app, |
| 330 | &KeyEvent::new(KeyCode::Enter, KeyModifiers::NONE), |
| 331 | last_char + Duration::from_millis(60), |
| 332 | )); |
| 333 | assert_eq!(app.input, "abc\n"); |
| 334 | |
| 335 | // Past the window measured from the last *keystroke* — the absorbed |
| 336 | // Enter bought no extra time, so this one submits. |
| 337 | assert!( |
| 338 | !handle_paste_burst_key( |
| 339 | &mut app, |
| 340 | &KeyEvent::new(KeyCode::Enter, KeyModifiers::NONE), |
| 341 | last_char + Duration::from_millis(121), |
| 342 | ), |
| 343 | "the second Enter must reach the submit path" |
| 344 | ); |
| 345 | assert_eq!(app.input, "abc\n", "no second newline may be inserted"); |
| 346 | } |
| 347 | |
| 348 | #[test] |
| 349 | fn paste_buffered_question_mark_does_not_fall_through_to_help_shortcut() { |
| 350 | let mut app = test_app(); |
| 351 | let t0 = Instant::now(); |
| 352 | |
| 353 | assert!(handle_paste_burst_key(&mut app, &plain('?'), t0)); |
| 354 | |
| 355 | assert!(app.input.is_empty(), "shortcut char stays buffered first"); |
| 356 | assert!(app.view_stack.is_empty(), "help modal must not open"); |
| 357 | assert!(app.flush_paste_burst_if_due( |
| 358 | t0 + crate::tui::paste_burst::PasteBurst::recommended_flush_delay() |
| 359 | )); |
| 360 | assert_eq!(app.input, "?"); |
| 361 | } |
| 362 | |
| 363 | /// Pin the IME-input contract: macOS/Windows input methods commit |
| 364 | /// each Chinese character as a single `KeyCode::Char(c)` event |
| 365 | /// after the candidate popup closes. Each codepoint fits in a |
| 366 | /// `char` (no surrogate pair concerns for BMP chars), so a |
| 367 | /// straightforward sequence of plain-char events must land in |
| 368 | /// `app.input` verbatim — no ASCII filter, no byte-vs-char index |
| 369 | /// drift, no paste-burst false-positive that buffers the chars |
| 370 | /// indefinitely. |
| 371 | #[test] |
| 372 | fn ime_chinese_chars_route_through_to_composer() { |
| 373 | let mut app = test_app(); |
| 374 | let t0 = Instant::now(); |
| 375 | |
| 376 | // Type the four Chinese codepoints "你好世界" one event at a |
| 377 | // time, with realistic ~50ms gaps so the paste-burst heuristic |
| 378 | // doesn't classify them as a paste burst. |
| 379 | for (i, ch) in "你好世界".chars().enumerate() { |
| 380 | let now = t0 + Duration::from_millis(50 * i as u64); |
| 381 | let _ = handle_paste_burst_key(&mut app, &plain(ch), now); |
| 382 | } |
| 383 | |
| 384 | // Past the active-flush delay so any buffered burst commits. |
| 385 | let after = t0 |
| 386 | + Duration::from_millis(50 * 4) |
| 387 | + crate::tui::paste_burst::PasteBurst::recommended_active_flush_delay(); |
| 388 | let _ = app.flush_paste_burst_if_due(after); |
| 389 | |
| 390 | assert_eq!( |
| 391 | app.input, "你好世界", |
| 392 | "IME-typed Chinese characters must land in composer verbatim" |
| 393 | ); |
| 394 | assert_eq!( |
| 395 | app.cursor_position, 4, |
| 396 | "cursor advances by one per codepoint, not per UTF-8 byte" |
| 397 | ); |
| 398 | } |
| 399 | |
| 400 | /// Pin the bracketed-paste contract for CJK content: pasted |
| 401 | /// Chinese text (e.g. when a user copies a question from a |
| 402 | /// Chinese website and pastes into the composer) must preserve |
| 403 | /// every codepoint and not double-count multi-byte chars in the |
| 404 | /// cursor position. |
| 405 | #[test] |
| 406 | fn bracketed_paste_preserves_chinese_and_mixed_text() { |
| 407 | let mut app = test_app(); |
| 408 | app.insert_paste_text("你好世界 hello 世界 café"); |
| 409 | assert_eq!(app.input, "你好世界 hello 世界 café"); |
| 410 | // 4 + 1 + 5 + 1 + 2 + 1 + 4 = 18 codepoints (counting é as one). |
| 411 | assert_eq!(app.cursor_position, 18); |
| 412 | } |
| 413 | |
| 414 | #[test] |
| 415 | fn paste_burst_detection_can_be_disabled_without_disabling_bracketed_paste() { |
| 416 | let mut app = test_app(); |
| 417 | app.use_paste_burst_detection = false; |
| 418 | |
| 419 | assert!(!handle_paste_burst_key( |
| 420 | &mut app, |
| 421 | &plain('a'), |
| 422 | Instant::now() |
| 423 | )); |
| 424 | assert!(app.input.is_empty()); |
| 425 | |
| 426 | app.insert_paste_text("line 1\r\nline 2"); |
| 427 | assert_eq!(app.input, "line 1\nline 2"); |
| 428 | assert!(app.use_bracketed_paste); |
| 429 | } |
| 430 | |
| 431 | /// Once the session has observed a real `Event::Paste`, the |
| 432 | /// rapid-keystroke heuristic must short-circuit. This pins the new |
| 433 | /// "auto-disable paste-burst on verified bracketed paste" behavior so |
| 434 | /// fast typing / IME commits / autocomplete on capable terminals can't |
| 435 | /// be mis-classified as a paste burst. |
| 436 | #[test] |
| 437 | fn paste_burst_short_circuits_after_bracketed_paste_observed() { |
| 438 | let mut app = test_app(); |
| 439 | app.use_paste_burst_detection = true; |
| 440 | app.bracketed_paste_seen = true; |
| 441 | |
| 442 | let t0 = Instant::now(); |
| 443 | for (i, ch) in "abcdefgh".chars().enumerate() { |
| 444 | // Type fast enough that paste-burst would normally fire. |
| 445 | let now = t0 + Duration::from_millis(i as u64); |
| 446 | assert!( |
| 447 | !handle_paste_burst_key(&mut app, &plain(ch), now), |
| 448 | "paste-burst must NOT consume keys once bracketed paste verified" |
| 449 | ); |
| 450 | } |
| 451 | // No buffering — every char fell through to the normal composer |
| 452 | // path (the test harness doesn't insert chars when the burst |
| 453 | // handler returns false; we only assert the short-circuit |
| 454 | // contract here). |
| 455 | assert!(app.input.is_empty()); |
| 456 | } |
| 457 | } |
| 458 |