From a49fec420b46caf8f4ca6d4ec9d5d2f09ffc42cc Mon Sep 17 00:00:00 2001
From: Postil Maintainer <morgaesis+git@morgaes.is>
Date: Sun, 9 Aug 2026 19:12:49 +0000
Subject: [PATCH] Exclude ignored paths before review planning

---
 docs/configuration.md |  2 ++
 src/diff.rs           | 12 ++++++++++++
 src/review.rs         |  2 +-
 tests/e2e.rs          | 38 ++++++++++++++++++++++++++++++++++++++
 4 files changed, 53 insertions(+), 1 deletion(-)

diff --git a/docs/configuration.md b/docs/configuration.md
index f031101..aff9a5b 100644
--- a/docs/configuration.md
+++ b/docs/configuration.md
@@ -40,6 +40,8 @@ model:
 
 Place organization-specific merge rules in `.postil/guardrails.md`. Place additions to the built-in prose policy in `.postil/content-policy.md`. Repository policy extends the built-in content policy unless `contentPolicy.enabled` is false.
 
+Ignored paths are excluded before review planning, so generated artifacts do not consume model context or bounded-review coverage.
+
 ## Environment
 
 | Variable | Purpose |
diff --git a/src/diff.rs b/src/diff.rs
index 3c0106a..7a3d356 100644
--- a/src/diff.rs
+++ b/src/diff.rs
@@ -2429,7 +2429,15 @@ fn read_length_prefixed(file: &mut File, context: &str) -> Result<Option<String>
 }
 
 pub fn prepare_review(snapshot: &DiffSnapshot) -> Result<PreparedReview> {
+    prepare_review_with_ignore(snapshot, &[])
+}
+
+pub fn prepare_review_with_ignore(
+    snapshot: &DiffSnapshot,
+    ignore_patterns: &[String],
+) -> Result<PreparedReview> {
     let text = snapshot.as_str();
+    let ignore = crate::filter::build_ignore_set(ignore_patterns)?;
     let mut windows = tempfile::tempfile().context("creating review-window spool")?;
     let mut window_lease = WorkspaceLease::new(snapshot.workspace_budget());
     let mut index = DiffIndex::default();
@@ -2462,6 +2470,10 @@ pub fn prepare_review(snapshot: &DiffSnapshot) -> Result<PreparedReview> {
         let end = next_diff_start(text, cursor + "diff --git ".len()).unwrap_or(text.len());
         let section = &text[cursor..end];
         let path = section_path(section).context("review section has an invalid path header")?;
+        if ignore.is_match(&path) {
+            cursor = end;
+            continue;
+        }
         if is_known_lockfile(&path)
             && let Some(evidence) = lockfile_evidence(&path, section)
         {
diff --git a/src/review.rs b/src/review.rs
index dcfbded..bdaa664 100644
--- a/src/review.rs
+++ b/src/review.rs
@@ -1125,7 +1125,7 @@ async fn review_diff(cfg: &Config, args: &ReviewArgs, input: ReviewInput<'_>) ->
         repository_source,
     } = input;
     let review_started = std::time::Instant::now();
-    let mut prepared = diff::prepare_review(diff_snapshot)?;
+    let mut prepared = diff::prepare_review_with_ignore(diff_snapshot, &cfg.ignore)?;
     let input_incomplete = prepared.reserved_anchor;
     let mut index = std::mem::take(&mut prepared.index);
     let incremental = matches!(scope, filter::ReconcileScope::Incremental { .. });
diff --git a/tests/e2e.rs b/tests/e2e.rs
index 059c83b..afdc315 100644
--- a/tests/e2e.rs
+++ b/tests/e2e.rs
@@ -2210,6 +2210,44 @@ async fn generated_named_source_is_not_omitted_from_review() {
     assert!(body.contains("eval(userInput)"));
 }
 
+#[tokio::test]
+async fn ignored_paths_are_removed_before_review_planning() {
+    let server = MockServer::start().await;
+    mock_review(&server, json!([])).await;
+
+    let dir = tempfile::tempdir().unwrap();
+    let diff = dir.path().join("ignored-source.diff");
+    std::fs::write(
+        &diff,
+        "diff --git a/generated/snapshot.json b/generated/snapshot.json\n--- a/generated/snapshot.json\n+++ b/generated/snapshot.json\n@@ -0,0 +1 @@\n+generated_snapshot_payload\ndiff --git a/src/live.rs b/src/live.rs\n--- a/src/live.rs\n+++ b/src/live.rs\n@@ -0,0 +1 @@\n+validate_live_path();\n",
+    )
+    .unwrap();
+    let config = dir.path().join("postil.yml");
+    std::fs::write(&config, "ignore:\n  - \"generated/**\"\n").unwrap();
+
+    let out = postil()
+        .current_dir(dir.path())
+        .env("POSTIL_API_BASE", server.uri())
+        .env("POSTIL_DISABLE_SCORER", "1")
+        .args(["review", "--diff-file"])
+        .arg(&diff)
+        .arg("--config")
+        .arg(&config)
+        .args(["--output", "json"])
+        .assert()
+        .success();
+
+    let envelope: Value = serde_json::from_slice(&out.get_output().stdout).unwrap();
+    assert!(envelope["findings"].as_array().unwrap().is_empty());
+    let requests = server.received_requests().await.unwrap();
+    assert_eq!(requests.len(), 1);
+    let body = String::from_utf8_lossy(&requests[0].body);
+    assert!(body.contains("src/live.rs"));
+    assert!(body.contains("validate_live_path"));
+    assert!(!body.contains("generated/snapshot.json"));
+    assert!(!body.contains("generated_snapshot_payload"));
+}
+
 #[tokio::test]
 async fn oversized_security_hunk_fails_before_provider_contact() {
     use std::fmt::Write as _;