Make conflict reporting optional

Author: Kobzol

rust-bors.example.toml

@@ -7,6 +7,10 @@ timeout = 3600
 # (Optional, defaults to false)
 merge_queue_enabled = true
 
+# Whether merge conflicts should be reported on PRs.
+# (Optional, defaults to false)
+report_merge_conflicts = true
+
 # Labels that will block approval when present on a PR
 # (Optional)
 labels_blocking_approval = ["final-comment-period", "proposed-final-comment-period"]

src/bors/handlers/pr_events.rs

@@ -366,7 +366,7 @@ mod tests {
 
     use crate::bors::PullRequestStatus;
     use crate::bors::merge_queue::AUTO_BUILD_CHECK_RUN_NAME;
-    use crate::tests::{BorsTester, WorkflowRunData};
+    use crate::tests::{BorsBuilder, BorsTester, GitHubState, WorkflowRunData};
     use crate::{
         database::{MergeableState, OctocrabMergeableState},
         tests::{User, default_branch_name, default_repo_name, run_test},
@@ -674,7 +674,7 @@ mod tests {
     }
 
     #[sqlx::test]
-    async fn conflict_message_unknown_sha(pool: sqlx::PgPool) {
+    async fn conflict_message_disabled_in_config(pool: sqlx::PgPool) {
         run_test(pool, async |tester: &mut BorsTester| {
             let pr = tester
                 .open_pr(default_repo_name(), |pr| {
@@ -687,6 +687,32 @@ mod tests {
                 })
                 .await;
             tester.push_to_branch(default_branch_name(), "sha").await?;
+
+            Ok(())
+        })
+        .await;
+    }
+
+    #[sqlx::test]
+    async fn conflict_message_unknown_sha(pool: sqlx::PgPool) {
+        BorsBuilder::new(pool)
+            .github(GitHubState::default().with_default_config(
+                r#"
+merge_queue_enabled = true
+report_merge_conflicts = true
+"#,
+            )).run_test(async |tester: &mut BorsTester| {
+            let pr = tester
+                .open_pr(default_repo_name(), |pr| {
+                    pr.mergeable_state = OctocrabMergeableState::Clean;
+                })
+                .await?;
+            tester
+                .modify_pr_state(pr.id(), |pr| {
+                    pr.mergeable_state = OctocrabMergeableState::Dirty;
+                })
+                .await;
+            tester.push_to_branch(default_branch_name(), "sha").await?;
             assert_snapshot!(tester.get_next_comment_text(pr).await?, @":umbrella: The latest upstream changes made this pull request unmergeable. Please [resolve the merge conflicts](https://rustc-dev-guide.rust-lang.org/git.html#rebasing-and-conflicts).");
 
             Ok(())
@@ -696,7 +722,13 @@ mod tests {
 
     #[sqlx::test]
     async fn conflict_message_unknown_sha_approved(pool: sqlx::PgPool) {
-        run_test(pool, async |tester: &mut BorsTester| {
+        BorsBuilder::new(pool)
+            .github(GitHubState::default().with_default_config(
+                r#"
+merge_queue_enabled = true
+report_merge_conflicts = true
+"#,
+            )).run_test(async |tester: &mut BorsTester| {
             let pr = tester
                 .open_pr(default_repo_name(), |pr| {
                     pr.mergeable_state = OctocrabMergeableState::Clean;
@@ -723,7 +755,13 @@ mod tests {
 
     #[sqlx::test]
     async fn conflict_message_known_sha(pool: sqlx::PgPool) {
-        run_test(pool, async |tester: &mut BorsTester| {
+        BorsBuilder::new(pool)
+            .github(GitHubState::default().with_default_config(
+                r#"
+merge_queue_enabled = true
+report_merge_conflicts = true
+"#,
+            )).run_test(async |tester: &mut BorsTester| {
             let pr2 = tester
                 .open_pr(default_repo_name(), |pr| {
                     pr.mergeable_state = OctocrabMergeableState::Clean;

src/bors/mergeability_queue.rs

@@ -442,6 +442,11 @@ async fn handle_pr_conflict(
 ) -> anyhow::Result<()> {
     tracing::info!("Pull request {pr:?} was likely unmergeable (source: {conflict_source:?})");
 
+    if !repo_state.config.load().report_merge_conflicts {
+        tracing::info!("Reporting merge conflicts is disabled, not doing anything further");
+        return Ok(());
+    }
+
     let Some(pr) = db.get_pull_request(&pr.repo, pr.pr_number).await? else {
         return Err(anyhow::anyhow!("Pull request {pr:?} was not found"));
     };

src/config.rs

@@ -36,6 +36,10 @@ pub struct RepositoryConfig {
     /// Defaults to false.
     #[serde(default)]
     pub merge_queue_enabled: bool,
+    /// Whether merge conflicts should be reported on PRs.
+    /// Defaults to false.
+    #[serde(default)]
+    pub report_merge_conflicts: bool,
 }
 
 /// Load a repository config from TOML.