Stop generating accepted-line fingerprints (#38473)

## What changed

- Replace accepted-line fingerprint generation with diff-based added and deleted line counts.
- Keep `line_fingerprints` in the analytics payload as a statically empty field for schema compatibility.
- Remove the fingerprint types and public parsing API that are no longer used.

## Testing

- Update diff parsing tests to cover accepted-line counts without generating fingerprints.

GitOrigin-RevId: 4247c76c7b56b1a323f70f960823937352b84f7b

codex-rs/analytics/src/accepted_lines.rs

@@ -1,17 +1,15 @@
 use crate::events::CodexAcceptedLineFingerprintsEventParams;
 use crate::events::CodexAcceptedLineFingerprintsEventRequest;
 use crate::events::TrackEventRequest;
-use crate::facts::AcceptedLineFingerprint;
 use codex_git_utils::canonicalize_git_remote_url;
 use codex_git_utils::get_git_remote_urls_assume_git_repo;
 use sha1::Digest;
 use std::path::Path;
 
 #[derive(Clone, Debug, PartialEq, Eq)]
-pub struct AcceptedLineFingerprintSummary {
-    pub accepted_added_lines: u64,
-    pub accepted_deleted_lines: u64,
-    pub line_fingerprints: Vec<AcceptedLineFingerprint>,
+pub(crate) struct AcceptedLineCounts {
+    pub(crate) accepted_added_lines: u64,
+    pub(crate) accepted_deleted_lines: u64,
 }
 
 pub(crate) struct AcceptedLineFingerprintEventInput {
@@ -24,21 +22,15 @@ pub(crate) struct AcceptedLineFingerprintEventInput {
     pub(crate) repo_hash: Option<String>,
     pub(crate) accepted_added_lines: u64,
     pub(crate) accepted_deleted_lines: u64,
-    pub(crate) line_fingerprints: Vec<AcceptedLineFingerprint>,
 }
 
-pub fn accepted_line_fingerprints_from_unified_diff(
-    unified_diff: &str,
-) -> AcceptedLineFingerprintSummary {
-    let mut current_path: Option<String> = None;
+pub(crate) fn accepted_line_counts_from_unified_diff(unified_diff: &str) -> AcceptedLineCounts {
     let mut in_hunk = false;
     let mut accepted_added_lines = 0;
     let mut accepted_deleted_lines = 0;
-    let mut line_fingerprints = Vec::new();
 
     for line in unified_diff.lines() {
         if line.starts_with("diff --git ") {
-            current_path = None;
             in_hunk = false;
             continue;
         }
@@ -48,25 +40,12 @@ pub fn accepted_line_fingerprints_from_unified_diff(
             continue;
         }
 
-        if !in_hunk && let Some(path) = line.strip_prefix("+++ ") {
-            current_path = normalize_diff_path(path);
+        if !in_hunk && (line.starts_with("+++ ") || line.starts_with("--- ")) {
             continue;
         }
 
-        if !in_hunk && line.starts_with("--- ") {
-            continue;
-        }
-
-        if let Some(added_line) = line.strip_prefix('+') {
+        if line.starts_with('+') {
             accepted_added_lines += 1;
-            if let Some(path) = current_path.as_deref()
-                && let Some(normalized_line) = normalize_effective_line(added_line)
-            {
-                line_fingerprints.push(AcceptedLineFingerprint {
-                    path_hash: fingerprint_hash("path", path),
-                    line_hash: fingerprint_hash("line", &normalized_line),
-                });
-            }
             continue;
         }
 
@@ -75,10 +54,9 @@ pub fn accepted_line_fingerprints_from_unified_diff(
         }
     }
 
-    AcceptedLineFingerprintSummary {
+    AcceptedLineCounts {
         accepted_added_lines,
         accepted_deleted_lines,
-        line_fingerprints,
     }
 }
 
@@ -104,7 +82,6 @@ pub(crate) fn accepted_line_fingerprint_event_requests(
         repo_hash,
         accepted_added_lines,
         accepted_deleted_lines,
-        line_fingerprints: _line_fingerprints,
     } = input;
 
     vec![TrackEventRequest::AcceptedLineFingerprints(Box::new(
@@ -120,9 +97,7 @@ pub(crate) fn accepted_line_fingerprint_event_requests(
                 repo_hash,
                 accepted_added_lines,
                 accepted_deleted_lines,
-                // Keep computing local fingerprints for parsing tests and future attribution,
-                // but do not upload path/line hashes in the analytics event payload.
-                line_fingerprints: Vec::new(),
+                line_fingerprints: [],
             },
         },
     ))]
@@ -140,40 +115,12 @@ pub async fn accepted_line_repo_hash_for_cwd(cwd: &Path) -> Option<String> {
         })
 }
 
-fn normalize_diff_path(path: &str) -> Option<String> {
-    let path = path.trim();
-    if path == "/dev/null" {
-        return None;
-    }
-
-    Some(
-        path.strip_prefix("b/")
-            .or_else(|| path.strip_prefix("a/"))
-            .unwrap_or(path)
-            .to_string(),
-    )
-}
-
-fn normalize_effective_line(line: &str) -> Option<String> {
-    let normalized = line.split_whitespace().collect::<Vec<_>>().join(" ");
-    if normalized.len() <= 3 {
-        return None;
-    }
-    if !normalized
-        .chars()
-        .any(|ch| ch.is_alphanumeric() || ch == '_')
-    {
-        return None;
-    }
-    Some(normalized)
-}
-
 #[cfg(test)]
 mod tests {
     use super::*;
 
     #[test]
-    fn parses_counts_and_effective_added_fingerprints() {
+    fn parses_accepted_line_counts() {
         let diff = "\
 diff --git a/src/lib.rs b/src/lib.rs
 index 1111111..2222222
@@ -187,24 +134,12 @@ index 1111111..2222222
  context
 ";
 
-        let summary = accepted_line_fingerprints_from_unified_diff(diff);
-
         assert_eq!(
-            summary,
-            AcceptedLineFingerprintSummary {
+            accepted_line_counts_from_unified_diff(diff),
+            AcceptedLineCounts {
                 accepted_added_lines: 3,
                 accepted_deleted_lines: 1,
-                line_fingerprints: vec![
-                    AcceptedLineFingerprint {
-                        path_hash: fingerprint_hash("path", "src/lib.rs"),
-                        line_hash: fingerprint_hash("line", "fn useful() {"),
-                    },
-                    AcceptedLineFingerprint {
-                        path_hash: fingerprint_hash("path", "src/lib.rs"),
-                        line_hash: fingerprint_hash("line", "return user.id;"),
-                    },
-                ],
-            }
+            },
         );
     }
 
@@ -220,11 +155,13 @@ index 0000000..1111111
 +print('hello')
 ";
 
-        let summary = accepted_line_fingerprints_from_unified_diff(diff);
-
-        assert_eq!(summary.accepted_added_lines, 1);
-        assert_eq!(summary.accepted_deleted_lines, 0);
-        assert_eq!(summary.line_fingerprints.len(), 1);
+        assert_eq!(
+            accepted_line_counts_from_unified_diff(diff),
+            AcceptedLineCounts {
+                accepted_added_lines: 1,
+                accepted_deleted_lines: 0,
+            },
+        );
     }
 
     #[test]
@@ -239,18 +176,12 @@ index 1111111..2222222
 +++ new value
 ";
 
-        let summary = accepted_line_fingerprints_from_unified_diff(diff);
-
         assert_eq!(
-            summary,
-            AcceptedLineFingerprintSummary {
+            accepted_line_counts_from_unified_diff(diff),
+            AcceptedLineCounts {
                 accepted_added_lines: 1,
                 accepted_deleted_lines: 1,
-                line_fingerprints: vec![AcceptedLineFingerprint {
-                    path_hash: fingerprint_hash("path", "src/lib.rs"),
-                    line_hash: fingerprint_hash("line", "++ new value"),
-                }],
-            }
+            },
         );
     }
 }