Fix workspace-relative added file paths (#1852)

Fix workspace relative path for `check-case-conflict` and
`check-added-large-files`

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: j178

crates/prek/src/git.rs

@@ -104,6 +104,10 @@ pub(crate) async fn get_added_files(root: &Path) -> Result<Vec<PathBuf>, Error>
         .current_dir(root)
         .arg("diff")
         .arg("--staged")
+        // `git diff --name-only` reports paths relative to the repository root by default,
+        // even when it runs inside a subdirectory. `--relative` keeps the output aligned
+        // with hooks, which receive filenames relative to their project root.
+        .arg("--relative")
         .arg("--name-only")
         .arg("--diff-filter=A")
         .arg("-z") // Use NUL as line terminator
@@ -634,12 +638,16 @@ pub(crate) async fn get_shared_repository_file_mode(mode: u32) -> Result<u32> {
     }
 }
 
-pub(crate) async fn get_lfs_files(paths: &[&Path]) -> Result<FxHashSet<PathBuf>, Error> {
+pub(crate) async fn get_lfs_files(
+    current_dir: &Path,
+    paths: &[&Path],
+) -> Result<FxHashSet<PathBuf>, Error> {
     if paths.is_empty() {
         return Ok(FxHashSet::default());
     }
 
     let mut child = git_cmd("git check-attr")?
+        .current_dir(current_dir)
         .arg("check-attr")
         .arg("filter")
         .arg("-z")

crates/prek/src/hooks/pre_commit_hooks/check_added_large_files.rs

@@ -49,7 +49,9 @@ pub(crate) async fn check_added_large_files(
         FileFilter::Files(add_files)
     };
 
-    let lfs_files = get_lfs_files(filenames).await?;
+    // Builtin hooks receive project-relative filenames, so git attribute lookups need to run
+    // from the project root for nested `.gitattributes` files to apply.
+    let lfs_files = get_lfs_files(hook.work_dir(), filenames).await?;
 
     let filenames = filenames
         .iter()

crates/prek/tests/builtin_hooks.rs

@@ -687,6 +687,85 @@ fn check_added_large_files_hook() -> Result<()> {
     Ok(())
 }
 
+#[test]
+fn check_added_large_files_workspace_mode_respects_project_relative_lfs_paths() -> Result<()> {
+    let context = TestContext::new();
+    context.init_project();
+
+    context.write_pre_commit_config("repos: []\n");
+
+    // Regression: builtin hooks receive project-relative filenames even in workspace mode.
+    // `check-added-large-files` must therefore resolve git-lfs attributes relative to the
+    // nested project root, not the workspace root.
+    let app = context.work_dir().child("app");
+    app.create_dir_all()?;
+    // Use `--enforce-all` so this regression isolates git-lfs attribute lookup in workspace
+    // mode instead of depending on the separate staged-file path filtering behavior.
+    app.child(PRE_COMMIT_CONFIG_YAML)
+        .write_str(indoc::indoc! {r"
+        repos:
+          - repo: builtin
+            hooks:
+              - id: check-added-large-files
+                args: ['--maxkb', '1', '--enforce-all']
+    "})?;
+    app.child(".gitattributes")
+        .write_str("*.dat filter=lfs diff=lfs merge=lfs -text")?;
+    app.child("large.dat").write_binary(&[0; 2048])?;
+
+    context.git_add(".");
+
+    cmd_snapshot!(context.filters(), context.run(), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    Running hooks for `app`:
+    check for added large files..............................................Passed
+
+    ----- stderr -----
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn check_added_large_files_workspace_mode_respects_project_relative_added_files() -> Result<()> {
+    let context = TestContext::new();
+    context.init_project();
+
+    context.write_pre_commit_config("repos: []\n");
+
+    let app = context.work_dir().child("app");
+    app.create_dir_all()?;
+    app.child(PRE_COMMIT_CONFIG_YAML)
+        .write_str(indoc::indoc! {r"
+        repos:
+          - repo: builtin
+            hooks:
+              - id: check-added-large-files
+                args: ['--maxkb', '1']
+    "})?;
+    app.child("large.bin").write_binary(&[0; 2048])?;
+
+    context.git_add(".");
+
+    cmd_snapshot!(context.filters(), context.run(), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    Running hooks for `app`:
+    check for added large files..............................................Failed
+    - hook id: check-added-large-files
+    - exit code: 1
+
+      large.bin (2 KB) exceeds 1 KB
+
+    ----- stderr -----
+    ");
+
+    Ok(())
+}
+
 #[test]
 fn tracked_file_exceeds_large_file_limit() -> Result<()> {
     let context = TestContext::new();
@@ -845,7 +924,11 @@ fn builtin_hooks_workspace_mode() -> Result<()> {
     - files were modified by this hook
 
       Fixing trailing_ws.txt
-    check for added large files..............................................Passed
+    check for added large files..............................................Failed
+    - hook id: check-added-large-files
+    - exit code: 1
+
+      large.bin (2 KB) exceeds 1 KB
 
     Running hooks for `.`:
     identity.................................................................Passed
@@ -870,18 +953,20 @@ fn builtin_hooks_workspace_mode() -> Result<()> {
     ----- stderr -----
     ");
 
-    // Fix YAML and JSON issues, then stage.
-    app.child("invalid.yaml").write_str("a:\n  b: c")?;
-    app.child("duplicate.yaml").write_str("a: 1\nb: 2")?;
-    app.child("invalid.json").write_str(r#"{"a": 1}"#)?;
+    // Manually fix the files that can't be auto-fixed.
+    app.child("invalid.yaml").write_str("a:\n  b: c\n")?;
+    app.child("duplicate.yaml").write_str("a: 1\nb: 2\n")?;
+    app.child("invalid.json")
+        .write_str(concat!(r#"{"a": 1}"#, "\n"))?;
     app.child("duplicate.json")
-        .write_str(r#"{"a": 1, "b": 2}"#)?;
+        .write_str(concat!(r#"{"a": 1, "b": 2}"#, "\n"))?;
+    app.child("large.bin").write_binary(&[0u8; 100])?;
     context.git_add(".");
 
-    // Second run: all hooks should pass.
-    cmd_snapshot!(context.filters(), context.run(), @r"
-    success: false
-    exit_code: 1
+    // Second run: all hooks should now pass.
+    cmd_snapshot!(context.filters(), context.run(), @"
+    success: true
+    exit_code: 0
     ----- stdout -----
     Running hooks for `app`:
     identity.................................................................Passed
@@ -901,15 +986,7 @@ fn builtin_hooks_workspace_mode() -> Result<()> {
       invalid.json
       .pre-commit-config.yaml
       eof_no_newline.txt
-    fix end of files.........................................................Failed
-    - hook id: end-of-file-fixer
-    - exit code: 1
-    - files were modified by this hook
-
-      Fixing invalid.yaml
-      Fixing duplicate.json
-      Fixing duplicate.yaml
-      Fixing invalid.json
+    fix end of files.........................................................Passed
     check yaml...............................................................Passed
     check json...............................................................Passed
     mixed line ending........................................................Passed
@@ -2450,6 +2527,64 @@ fn check_case_conflict_among_new_files() -> Result<()> {
     Ok(())
 }
 
+#[test]
+fn check_case_conflict_workspace_mode_includes_added_files() -> Result<()> {
+    let context = TestContext::new();
+    context.init_project();
+
+    if !is_case_sensitive_filesystem(&context)? {
+        return Ok(());
+    }
+
+    context.write_pre_commit_config("repos: []\n");
+
+    let app = context.work_dir().child("app");
+    app.create_dir_all()?;
+    app.child("foo.txt").write_str("existing file")?;
+    app.child("trigger.txt").write_str("tracked trigger")?;
+    context.git_add(".");
+    context.git_commit("Initial commit");
+
+    app.child(PRE_COMMIT_CONFIG_YAML)
+        .write_str(indoc::indoc! {r"
+        repos:
+          - repo: builtin
+            hooks:
+              - id: check-case-conflict
+    "})?;
+
+    app.child("FOO.txt").write_str("conflicting case")?;
+    context.git_add("app/FOO.txt");
+
+    // Regression: in workspace mode, `get_added_files()` must return paths relative to the
+    // nested project root so added files still participate in conflict detection even when
+    // `--files` only names some other file in that project.
+    cmd_snapshot!(
+        context.filters(),
+        context
+            .run()
+            .arg("check-case-conflict")
+            .arg("--files")
+            .arg("app/trigger.txt"),
+        @r#"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    Running hooks for `app`:
+    check for case conflicts.................................................Failed
+    - hook id: check-case-conflict
+    - exit code: 1
+
+      Case-insensitivity conflict found: FOO.txt
+      Case-insensitivity conflict found: foo.txt
+
+    ----- stderr -----
+    "#
+    );
+
+    Ok(())
+}
+
 #[test]
 fn check_json5() -> Result<()> {
     let context = TestContext::new();