| 1 | //! Whether a pull request merges cleanly into the branch it targets, worked |
| 2 | //! out ahead of time, as GitHub does, rather than discovered when a merge |
| 3 | //! or the merge queue trips over it. |
| 4 | //! |
| 5 | //! It is worked out whenever the pull request's head or its target branch |
| 6 | //! moves, once per pair of commits. The first pass needs no sandbox: if the |
| 7 | //! files the pull request changed since it and the branch last agreed share |
| 8 | //! none with the files the branch changed since then, the merge cannot |
| 9 | //! conflict. Otherwise a `pull.mergecheck` event asks the runner for a short |
| 10 | //! probe in a sandbox, which merges the two without an agent and reports the |
| 11 | //! files that conflict. Only so many probes run at once per repository; the |
| 12 | //! rest wait their turn and start as earlier ones report. |
| 13 | |
| 14 | use std::collections::HashSet; |
| 15 | |
| 16 | use g1t_contracts::repos::{BehindArgs, Divergence, GetByIdArgs, Repo, RepoPath}; |
| 17 | use g1t_contracts::time::rfc3339; |
| 18 | use g1t_contracts::work::*; |
| 19 | use g1t_contracts::{FailureCode, Outcome}; |
| 20 | use g1t_kit::now_ms; |
| 21 | use serde::Deserialize; |
| 22 | use worker::Result; |
| 23 | |
| 24 | use crate::Work; |
| 25 | use crate::checks::{hash, new_token}; |
| 26 | use crate::rows::{NumberRow, ValueRow}; |
| 27 | |
| 28 | /// How long a probe is waited for before it is asked for again. |
| 29 | const PROBE_MINUTES: u64 = 10; |
| 30 | /// How many probes one repository may have running at once. |
| 31 | const MAX_PROBES: u32 = 3; |
| 32 | /// How many conflicting files are kept. |
| 33 | const MAX_CONFLICTS: usize = 100; |
| 34 | /// How many open pull requests are looked at when their target moves. |
| 35 | const MAX_TARGETING: u32 = 100; |
| 36 | |
| 37 | #[derive(Deserialize)] |
| 38 | struct MergeRow { |
| 39 | mergeable: Option<String>, |
| 40 | conflicts: Option<String>, |
| 41 | mergeable_key: Option<String>, |
| 42 | mergeable_until: Option<String>, |
| 43 | } |
| 44 | |
| 45 | #[derive(Deserialize)] |
| 46 | struct ProbeRow { |
| 47 | id: String, |
| 48 | repo_id: String, |
| 49 | mergeable_key: Option<String>, |
| 50 | mergeable_token_hash: Option<String>, |
| 51 | } |
| 52 | |
| 53 | /// What a push moved, as far as the pull requests into it go. |
| 54 | pub(crate) enum Moved<'a> { |
| 55 | /// The repository's default branch: every open pull request into it, |
| 56 | /// whose base is stored as none. |
| 57 | DefaultBranch, |
| 58 | /// Another branch: the open pull requests into that one. |
| 59 | Branch(&'a str), |
| 60 | /// A tag, or anything else nothing merges into. |
| 61 | Nothing, |
| 62 | } |
| 63 | |
| 64 | /// The pair of commits an answer is for. |
| 65 | fn key(divergence: &Divergence) -> String { |
| 66 | format!("{}..{}", divergence.head, divergence.base) |
| 67 | } |
| 68 | |
| 69 | /// Whether the cheap first pass leaves the question open, so that a probe |
| 70 | /// has to merge the two. It is settled when the branch has not moved, or |
| 71 | /// when the two sides changed no file in common. |
| 72 | pub(crate) fn needs_probe(divergence: &Divergence) -> bool { |
| 73 | if !divergence.behind { |
| 74 | return false; |
| 75 | } |
| 76 | if divergence.truncated { |
| 77 | return true; |
| 78 | } |
| 79 | let ours: HashSet<&str> = divergence.ours.iter().map(String::as_str).collect(); |
| 80 | divergence.theirs.iter().any(|path| ours.contains(path.as_str())) |
| 81 | } |
| 82 | |
| 83 | /// Paths as a sandbox reported them, tidied: trimmed, without duplicates, |
| 84 | /// and no more than are useful. |
| 85 | pub(crate) fn tidy(paths: Vec<String>) -> Vec<String> { |
| 86 | let mut tidy: Vec<String> = Vec::new(); |
| 87 | for path in paths { |
| 88 | let path = path.trim().to_owned(); |
| 89 | if !path.is_empty() && !tidy.contains(&path) { |
| 90 | tidy.push(path); |
| 91 | } |
| 92 | if tidy.len() == MAX_CONFLICTS { |
| 93 | break; |
| 94 | } |
| 95 | } |
| 96 | tidy |
| 97 | } |
| 98 | |
| 99 | impl Work { |
| 100 | async fn merge_row(&self, pull_id: &str) -> Result<Option<MergeRow>> { |
| 101 | self.db |
| 102 | .prepare( |
| 103 | "SELECT mergeable, conflicts, mergeable_key, mergeable_until |
| 104 | FROM pulls WHERE id = ?", |
| 105 | ) |
| 106 | .bind(&[pull_id.into()])? |
| 107 | .first::<MergeRow>(None) |
| 108 | .await |
| 109 | } |
| 110 | |
| 111 | /// Works out whether a pull request merges cleanly as it and its target |
| 112 | /// are now, unless that pair of commits was already worked out or is |
| 113 | /// being. Settles it at once where it can, and asks for a probe where |
| 114 | /// it cannot. |
| 115 | pub(crate) async fn assess_mergeability(&self, pull: &Pull) -> Result<()> { |
| 116 | if !pull.status.is_active() { |
| 117 | return Ok(()); |
| 118 | } |
| 119 | let divergence: Option<Divergence> = g1t_kit::call( |
| 120 | &self.repos, |
| 121 | "divergence", |
| 122 | &BehindArgs { |
| 123 | source_id: pull.fork_repo_id.clone().unwrap_or_else(|| pull.repo_id.clone()), |
| 124 | branch: pull.branch.clone(), |
| 125 | target_branch: pull.base.clone().filter(|base| !base.is_empty()), |
| 126 | }, |
| 127 | ) |
| 128 | .await?; |
| 129 | // Nothing pushed yet. |
| 130 | let Some(divergence) = divergence else { |
| 131 | return Ok(()); |
| 132 | }; |
| 133 | let key = key(&divergence); |
| 134 | let now = now_ms(); |
| 135 | let behind = u32::from(divergence.behind); |
| 136 | let row = self.merge_row(&pull.id).await?; |
| 137 | if let Some(row) = &row |
| 138 | && row.mergeable_key.as_deref() == Some(key.as_str()) |
| 139 | { |
| 140 | // Whether it is behind goes with the pair of commits; a row from |
| 141 | // before it was kept gets it now. |
| 142 | self.db |
| 143 | .prepare("UPDATE pulls SET behind = ?1 WHERE id = ?2 AND behind IS NOT ?1") |
| 144 | .bind(&[behind.into(), pull.id.as_str().into()])? |
| 145 | .run() |
| 146 | .await?; |
| 147 | let settled = match row.mergeable.as_deref() { |
| 148 | Some("clean" | "conflicting" | "unknown") => true, |
| 149 | // A probe that is still being waited for. |
| 150 | Some("checking") => row |
| 151 | .mergeable_until |
| 152 | .as_deref() |
| 153 | .is_some_and(|until| until > rfc3339(now).as_str()), |
| 154 | _ => false, |
| 155 | }; |
| 156 | if settled { |
| 157 | return Ok(()); |
| 158 | } |
| 159 | } |
| 160 | if !needs_probe(&divergence) { |
| 161 | self.db |
| 162 | .prepare( |
| 163 | "UPDATE pulls |
| 164 | SET mergeable = 'clean', conflicts = '[]', mergeable_key = ?, behind = ?, |
| 165 | mergeable_token_hash = NULL, mergeable_until = NULL |
| 166 | WHERE id = ?", |
| 167 | ) |
| 168 | .bind(&[key.as_str().into(), behind.into(), pull.id.as_str().into()])? |
| 169 | .run() |
| 170 | .await?; |
| 171 | // It may have been conflicting before this push. |
| 172 | if row.is_some_and(|row| row.mergeable.as_deref() == Some("conflicting")) { |
| 173 | self.announce_mergeability(pull).await?; |
| 174 | } |
| 175 | return Ok(()); |
| 176 | } |
| 177 | self.db |
| 178 | .prepare( |
| 179 | "UPDATE pulls |
| 180 | SET mergeable = 'checking', conflicts = '[]', mergeable_key = ?, behind = ?, |
| 181 | mergeable_token_hash = NULL, mergeable_until = ? |
| 182 | WHERE id = ?", |
| 183 | ) |
| 184 | .bind(&[ |
| 185 | key.as_str().into(), |
| 186 | behind.into(), |
| 187 | rfc3339(now + PROBE_MINUTES * 60 * 1000).into(), |
| 188 | pull.id.as_str().into(), |
| 189 | ])? |
| 190 | .run() |
| 191 | .await?; |
| 192 | self.ask_for_probe(pull, &divergence.head).await |
| 193 | } |
| 194 | |
| 195 | async fn ask_for_probe(&self, pull: &Pull, head: &str) -> Result<()> { |
| 196 | self.publish_as( |
| 197 | "pull.mergecheck", |
| 198 | &pull.repo_id, |
| 199 | None, |
| 200 | g1t_contracts::events::PullEvent { |
| 201 | commit: Some(head.to_owned()), |
| 202 | ..Self::pull_event(pull) |
| 203 | }, |
| 204 | ) |
| 205 | .await |
| 206 | } |
| 207 | |
| 208 | /// Says that a pull request's mergeability settled, so that the runner |
| 209 | /// looks again at one g1t is seeing through: a conflict is the agent's |
| 210 | /// to resolve. |
| 211 | async fn announce_mergeability(&self, pull: &Pull) -> Result<()> { |
| 212 | self.publish_as("pull.mergeability", &pull.repo_id, None, Self::pull_event(pull)) |
| 213 | .await |
| 214 | } |
| 215 | |
| 216 | /// Works out mergeability again after a push: for the pull requests |
| 217 | /// whose heads it moved, and, when it moved a branch pull requests |
| 218 | /// merge into, for every open pull request into it. A failure is logged |
| 219 | /// and not passed on, so that it never holds up the rest of the push. |
| 220 | pub(crate) async fn after_push(&self, repo_id: &str, into: Moved<'_>, moved: &[String]) { |
| 221 | let mut ids: Vec<String> = moved.to_vec(); |
| 222 | let base = match into { |
| 223 | Moved::DefaultBranch => Some(None), |
| 224 | Moved::Branch(branch) => Some(Some(branch)), |
| 225 | Moved::Nothing => None, |
| 226 | }; |
| 227 | if let Some(base) = base { |
| 228 | match self.targeting(repo_id, base).await { |
| 229 | Ok(targeting) => { |
| 230 | for id in targeting { |
| 231 | if !ids.contains(&id) { |
| 232 | ids.push(id); |
| 233 | } |
| 234 | } |
| 235 | } |
| 236 | Err(error) => worker::console_warn!("mergeability: {error}"), |
| 237 | } |
| 238 | } |
| 239 | for id in ids { |
| 240 | let assessed = async { |
| 241 | if let Some(pull) = self.pull_by_id(&id).await? { |
| 242 | self.assess_mergeability(&pull).await?; |
| 243 | } |
| 244 | Ok::<_, worker::Error>(()) |
| 245 | }; |
| 246 | if let Err(error) = assessed.await { |
| 247 | worker::console_warn!("mergeability of {id}: {error}"); |
| 248 | } |
| 249 | } |
| 250 | } |
| 251 | |
| 252 | /// The open pull requests into a branch of a repository (`None`: its |
| 253 | /// default branch), most recently active first. |
| 254 | async fn targeting(&self, repo_id: &str, base: Option<&str>) -> Result<Vec<String>> { |
| 255 | Ok(self |
| 256 | .db |
| 257 | .prepare( |
| 258 | "SELECT id AS value FROM pulls |
| 259 | WHERE repo_id = ? AND status IN ('draft', 'open') AND base_branch IS ? |
| 260 | ORDER BY updated_at DESC LIMIT ?", |
| 261 | ) |
| 262 | .bind(&[repo_id.into(), base.map_or(worker::wasm_bindgen::JsValue::NULL, Into::into), MAX_TARGETING.into()])? |
| 263 | .all() |
| 264 | .await? |
| 265 | .results::<ValueRow>()? |
| 266 | .into_iter() |
| 267 | .map(|row| row.value) |
| 268 | .collect()) |
| 269 | } |
| 270 | |
| 271 | /// Where a pull request's mergeability stands, for showing it. One that |
| 272 | /// was never worked out, or whose probe was given up on, is worked out |
| 273 | /// now. A conflict found for an older head is not shown as one. |
| 274 | pub(crate) async fn mergeability(&self, pull: &Pull) -> Result<(Mergeable, Vec<String>)> { |
| 275 | if !pull.status.is_active() || pull.head_commit.is_none() { |
| 276 | return Ok((Mergeable::Unknown, Vec::new())); |
| 277 | } |
| 278 | // As read for this request, if it was; read again after working it out. |
| 279 | let row = match self.prefetched_pull(&pull.id) { |
| 280 | Some(found) => found.first::<MergeRow>(crate::prefetch::Slot::Pull)?, |
| 281 | None => self.merge_row(&pull.id).await?, |
| 282 | }; |
| 283 | let now = rfc3339(now_ms()); |
| 284 | let stale = row.as_ref().is_none_or(|row| { |
| 285 | row.mergeable_key.is_none() |
| 286 | || (row.mergeable.as_deref() == Some("checking") |
| 287 | && row.mergeable_until.as_deref().is_none_or(|until| until < now.as_str())) |
| 288 | }); |
| 289 | let row = if stale { |
| 290 | if let Err(error) = self.assess_mergeability(pull).await { |
| 291 | worker::console_warn!("mergeability of {}: {error}", pull.id); |
| 292 | } |
| 293 | // What was read for this request is out of date now. |
| 294 | self.keep_prefetched(None); |
| 295 | self.merge_row(&pull.id).await? |
| 296 | } else { |
| 297 | row |
| 298 | }; |
| 299 | let Some(row) = row else { |
| 300 | return Ok((Mergeable::Unknown, Vec::new())); |
| 301 | }; |
| 302 | let current = row |
| 303 | .mergeable_key |
| 304 | .as_deref() |
| 305 | .and_then(|key| key.split_once("..")) |
| 306 | .is_some_and(|(head, _)| Some(head) == pull.head_commit.as_deref()); |
| 307 | let state = Mergeable::parse(row.mergeable.as_deref()); |
| 308 | if state == Mergeable::Conflicting && !current { |
| 309 | return Ok((Mergeable::Checking, Vec::new())); |
| 310 | } |
| 311 | let conflicts = if state == Mergeable::Conflicting { |
| 312 | row.conflicts |
| 313 | .as_deref() |
| 314 | .and_then(|conflicts| serde_json::from_str(conflicts).ok()) |
| 315 | .unwrap_or_default() |
| 316 | } else { |
| 317 | Vec::new() |
| 318 | }; |
| 319 | Ok((state, conflicts)) |
| 320 | } |
| 321 | |
| 322 | /// The files that conflict, if the pull request as it is now is known |
| 323 | /// to conflict with its target as it is now. |
| 324 | pub(crate) async fn conflicting_files(&self, pull: &Pull) -> Result<Option<Vec<String>>> { |
| 325 | let row = match self.prefetched_pull(&pull.id) { |
| 326 | Some(found) => found.first::<MergeRow>(crate::prefetch::Slot::Pull)?, |
| 327 | None => self.merge_row(&pull.id).await?, |
| 328 | }; |
| 329 | let Some(row) = row else { |
| 330 | return Ok(None); |
| 331 | }; |
| 332 | if row.mergeable.as_deref() != Some("conflicting") { |
| 333 | return Ok(None); |
| 334 | } |
| 335 | let current = row |
| 336 | .mergeable_key |
| 337 | .as_deref() |
| 338 | .and_then(|key| key.split_once("..")) |
| 339 | .is_some_and(|(head, _)| Some(head) == pull.head_commit.as_deref()); |
| 340 | if !current { |
| 341 | return Ok(None); |
| 342 | } |
| 343 | Ok(Some( |
| 344 | row.conflicts |
| 345 | .as_deref() |
| 346 | .and_then(|conflicts| serde_json::from_str(conflicts).ok()) |
| 347 | .unwrap_or_default(), |
| 348 | )) |
| 349 | } |
| 350 | |
| 351 | /// Claims the probe a `pull.mergecheck` event asked for, and returns |
| 352 | /// what a sandbox needs to carry it out. |
| 353 | pub(crate) async fn start_mergecheck(&self, a: StartMergecheckArgs) -> Result<Outcome<MergecheckJob>> { |
| 354 | let Some(pull) = self.pull_by_id(&a.pull_id).await? else { |
| 355 | return Ok(Outcome::fail(FailureCode::NotFound, "Pull request not found.")); |
| 356 | }; |
| 357 | if !pull.status.is_active() { |
| 358 | return Ok(Outcome::fail( |
| 359 | FailureCode::Conflict, |
| 360 | format!("This pull request is already {}.", pull.status.as_str()), |
| 361 | )); |
| 362 | } |
| 363 | let Some(row) = self.merge_row(&pull.id).await? else { |
| 364 | return Ok(Outcome::fail(FailureCode::NotFound, "Pull request not found.")); |
| 365 | }; |
| 366 | let Some((head, base)) = row |
| 367 | .mergeable_key |
| 368 | .as_deref() |
| 369 | .filter(|_| row.mergeable.as_deref() == Some("checking")) |
| 370 | .and_then(|key| key.split_once("..")) |
| 371 | .map(|(head, base)| (head.to_owned(), base.to_owned())) |
| 372 | else { |
| 373 | return Ok(Outcome::fail( |
| 374 | FailureCode::Conflict, |
| 375 | "Nothing is waiting to be checked for this pull request.", |
| 376 | )); |
| 377 | }; |
| 378 | let now = now_ms(); |
| 379 | let timestamp = rfc3339(now); |
| 380 | let running = self |
| 381 | .db |
| 382 | .prepare( |
| 383 | "SELECT count(*) AS n FROM pulls |
| 384 | WHERE repo_id = ? AND id != ? AND mergeable = 'checking' |
| 385 | AND mergeable_token_hash IS NOT NULL AND mergeable_until > ?", |
| 386 | ) |
| 387 | .bind(&[pull.repo_id.as_str().into(), pull.id.as_str().into(), timestamp.as_str().into()])? |
| 388 | .first::<NumberRow>(None) |
| 389 | .await? |
| 390 | .map_or(0, |row| row.n); |
| 391 | if running >= MAX_PROBES { |
| 392 | // It waits, and starts when one of those reports. |
| 393 | return Ok(Outcome::fail( |
| 394 | FailureCode::Conflict, |
| 395 | "This repository has as many merge checks running as it may.", |
| 396 | )); |
| 397 | } |
| 398 | let token = new_token(); |
| 399 | let claimed = self |
| 400 | .db |
| 401 | .prepare( |
| 402 | "UPDATE pulls SET mergeable_token_hash = ?, mergeable_until = ? |
| 403 | WHERE id = ? AND mergeable = 'checking' AND mergeable_key = ? |
| 404 | AND (mergeable_token_hash IS NULL OR mergeable_until < ?) |
| 405 | RETURNING id AS value", |
| 406 | ) |
| 407 | .bind(&[ |
| 408 | hash(&token).into(), |
| 409 | rfc3339(now + PROBE_MINUTES * 60 * 1000).into(), |
| 410 | pull.id.as_str().into(), |
| 411 | format!("{head}..{base}").into(), |
| 412 | timestamp.as_str().into(), |
| 413 | ])? |
| 414 | .first::<ValueRow>(None) |
| 415 | .await?; |
| 416 | if claimed.is_none() { |
| 417 | return Ok(Outcome::fail( |
| 418 | FailureCode::Conflict, |
| 419 | "This pull request is already being checked.", |
| 420 | )); |
| 421 | } |
| 422 | // Its owner (whoever asked g1t for it, or its author) can read both |
| 423 | // the repository and the change. |
| 424 | let repo: Outcome<Repo> = g1t_kit::call( |
| 425 | &self.repos, |
| 426 | "get_by_id", |
| 427 | &GetByIdArgs { |
| 428 | id: pull.repo_id.clone(), |
| 429 | viewer: self.owner_viewer(&pull).await?, |
| 430 | }, |
| 431 | ) |
| 432 | .await?; |
| 433 | let Outcome::Ok(repo) = crate::retired::unless_archived(repo) else { |
| 434 | return Ok(Outcome::fail(FailureCode::NotFound, "Pull request not found.")); |
| 435 | }; |
| 436 | let path = RepoPath { |
| 437 | namespace: repo.namespace.clone(), |
| 438 | name: repo.name.clone(), |
| 439 | }; |
| 440 | Ok(Outcome::Ok(MergecheckJob { |
| 441 | pull_id: pull.id.clone(), |
| 442 | token, |
| 443 | source: pull.fork.clone().unwrap_or_else(|| path.clone()), |
| 444 | branch: pull.branch.clone().unwrap_or_else(|| repo.default_branch.clone()), |
| 445 | repo: path, |
| 446 | number: pull.number, |
| 447 | // The branch it merges into. |
| 448 | default_branch: pull.base_branch(&repo.default_branch).to_owned(), |
| 449 | base, |
| 450 | head, |
| 451 | author: pull.requested_by.unwrap_or(pull.author), |
| 452 | })) |
| 453 | } |
| 454 | |
| 455 | /// Records what a probe found. Its token is the only credential, and a |
| 456 | /// probe for a pair of commits that has since moved on is refused. |
| 457 | pub(crate) async fn report_mergecheck(&self, a: ReportMergecheckArgs) -> Result<Outcome<Mergeable>> { |
| 458 | let row = self |
| 459 | .db |
| 460 | .prepare("SELECT id, repo_id, mergeable_key, mergeable_token_hash FROM pulls WHERE id = ?") |
| 461 | .bind(&[a.pull_id.as_str().into()])? |
| 462 | .first::<ProbeRow>(None) |
| 463 | .await?; |
| 464 | let Some(row) = row.filter(|row| row.mergeable_token_hash.as_deref() == Some(hash(&a.token).as_str())) else { |
| 465 | return Ok(Outcome::fail(FailureCode::NotFound, "Merge check not found.")); |
| 466 | }; |
| 467 | let conflicts = tidy(a.conflicts); |
| 468 | let state = if a.error.is_some() { |
| 469 | Mergeable::Unknown |
| 470 | } else if conflicts.is_empty() { |
| 471 | Mergeable::Clean |
| 472 | } else { |
| 473 | Mergeable::Conflicting |
| 474 | }; |
| 475 | if let Some(error) = &a.error { |
| 476 | worker::console_warn!("merge check of {} could not run: {error}", row.id); |
| 477 | } |
| 478 | self.db |
| 479 | .prepare( |
| 480 | "UPDATE pulls |
| 481 | SET mergeable = ?, conflicts = ?, mergeable_token_hash = NULL, mergeable_until = NULL |
| 482 | WHERE id = ? AND mergeable_key IS ? AND mergeable_token_hash = ?", |
| 483 | ) |
| 484 | .bind(&[ |
| 485 | state.as_str().into(), |
| 486 | serde_json::to_string(&conflicts)?.into(), |
| 487 | row.id.as_str().into(), |
| 488 | crate::optional(&row.mergeable_key), |
| 489 | hash(&a.token).into(), |
| 490 | ])? |
| 491 | .run() |
| 492 | .await?; |
| 493 | if let Some(pull) = self.pull_by_id(&row.id).await? { |
| 494 | self.announce_mergeability(&pull).await?; |
| 495 | } |
| 496 | // The next one waiting its turn in this repository. |
| 497 | let waiting = self |
| 498 | .db |
| 499 | .prepare( |
| 500 | "SELECT id AS value FROM pulls |
| 501 | WHERE repo_id = ? AND mergeable = 'checking' AND mergeable_token_hash IS NULL |
| 502 | AND status IN ('draft', 'open') |
| 503 | ORDER BY updated_at DESC LIMIT 1", |
| 504 | ) |
| 505 | .bind(&[row.repo_id.as_str().into()])? |
| 506 | .first::<ValueRow>(None) |
| 507 | .await?; |
| 508 | if let Some(waiting) = waiting |
| 509 | && let Some(pull) = self.pull_by_id(&waiting.value).await? |
| 510 | { |
| 511 | let head = pull.head_commit.clone().unwrap_or_default(); |
| 512 | self.ask_for_probe(&pull, &head).await?; |
| 513 | } |
| 514 | Ok(Outcome::Ok(state)) |
| 515 | } |
| 516 | } |
| 517 | |
| 518 | #[cfg(test)] |
| 519 | mod tests { |
| 520 | use super::*; |
| 521 | |
| 522 | fn divergence(behind: bool, ours: &[&str], theirs: &[&str]) -> Divergence { |
| 523 | Divergence { |
| 524 | head: "h".into(), |
| 525 | base: "b".into(), |
| 526 | merge_base: Some("m".into()), |
| 527 | behind, |
| 528 | ours: ours.iter().map(|path| (*path).to_owned()).collect(), |
| 529 | theirs: theirs.iter().map(|path| (*path).to_owned()).collect(), |
| 530 | truncated: false, |
| 531 | } |
| 532 | } |
| 533 | |
| 534 | #[test] |
| 535 | fn a_branch_that_has_not_moved_cannot_conflict() { |
| 536 | assert!(!needs_probe(&divergence(false, &["a.rs"], &[]))); |
| 537 | } |
| 538 | |
| 539 | #[test] |
| 540 | fn changes_to_different_files_cannot_conflict() { |
| 541 | assert!(!needs_probe(&divergence(true, &["a.rs", "b.rs"], &["c.rs"]))); |
| 542 | } |
| 543 | |
| 544 | #[test] |
| 545 | fn changes_to_the_same_file_are_probed() { |
| 546 | assert!(needs_probe(&divergence(true, &["a.rs", "b.rs"], &["b.rs"]))); |
| 547 | } |
| 548 | |
| 549 | #[test] |
| 550 | fn a_comparison_cut_short_is_probed() { |
| 551 | let cut = Divergence { |
| 552 | truncated: true, |
| 553 | ..divergence(true, &["a.rs"], &["c.rs"]) |
| 554 | }; |
| 555 | assert!(needs_probe(&cut)); |
| 556 | } |
| 557 | |
| 558 | #[test] |
| 559 | fn reported_paths_are_tidied() { |
| 560 | let paths = vec![" src/a.rs ".to_owned(), "src/a.rs".to_owned(), String::new(), "b.rs".to_owned()]; |
| 561 | assert_eq!(tidy(paths), ["src/a.rs", "b.rs"]); |
| 562 | let many: Vec<String> = (0..150).map(|n| format!("f{n}")).collect(); |
| 563 | assert_eq!(tidy(many).len(), MAX_CONFLICTS); |
| 564 | } |
| 565 | } |