fix(core): vcs root resolution (#9514)

Author: ematipico

.changeset/fix-vcs-root-ignore-file.md

@@ -0,0 +1,5 @@
+---
+"@biomejs/biome": patch
+---
+
+Fixed [#6964](https://github.com/biomejs/biome/issues/6964): Biome now correctly resolves the `.gitignore` file relative to `vcs.root` when configured. Previously, the `vcs.root` setting was ignored and Biome always looked for the ignore file in the workspace directory.

crates/biome_cli/tests/cases/vcs_ignored_files.rs

@@ -264,6 +264,52 @@ fn should_fail_when_ignore_file_is_absent() {
     ));
 }
 
+#[test]
+fn should_resolve_gitignore_using_vcs_root() {
+    let mut fs = TemporaryFs::new("should_resolve_gitignore_using_vcs_root");
+    let mut console = BufferConsole::default();
+
+    // .gitignore is at the repo root (one level up from the workspace)
+    fs.create_file(".gitignore", "**/file2.js\n");
+
+    // biome.json is in a subdirectory (workspace), with vcs.root pointing to parent
+    fs.create_file(
+        "workspace/biome.json",
+        r#"{
+            "vcs": {
+                "enabled": true,
+                "clientKind": "git",
+                "useIgnoreFile": true,
+                "root": ".."
+            }
+        }"#,
+    );
+
+    // This file should be formatted (not ignored)
+    fs.create_file("workspace/file1.js", UNFORMATTED);
+    // This file should be ignored by .gitignore at the root
+    fs.create_file("workspace/file2.js", UNFORMATTED);
+
+    // Run CLI from the workspace subdirectory
+    fs.append_to_working_directory("workspace");
+
+    let result = run_cli_with_dyn_fs(
+        Box::new(fs.create_os()),
+        &mut console,
+        Args::from(["format", fs.cli_path()].as_slice()),
+    );
+
+    assert!(result.is_err(), "run_cli returned {result:?}");
+
+    assert_cli_snapshot(SnapshotPayload::new(
+        module_path!(),
+        "should_resolve_gitignore_using_vcs_root",
+        fs.create_mem(),
+        console,
+        result,
+    ));
+}
+
 #[test]
 fn should_ignore_absolute_paths_in_ignore_file_with_glob() {
     let mut fs = TemporaryFs::new("should_ignore_absolute_paths_in_ignore_file_with_glob");

crates/biome_cli/tests/snapshots/main_cases_vcs_ignored_files/ignore_vcs_os_independent_parse.snap

@@ -26,6 +26,7 @@ file3.js
 
 ```js
 blah.call();
+
 ```
 
 ## `file2.js`

crates/biome_cli/tests/snapshots/main_cases_vcs_ignored_files/include_vcs_ignore_cascade.snap

@@ -29,7 +29,8 @@ file4.js
 ## `file1.js`
 
 ```js
-  statement(  )  
+statement();
+
 ```
 
 ## `file2.js`

crates/biome_cli/tests/snapshots/main_cases_vcs_ignored_files/should_resolve_gitignore_using_vcs_root.snap

@@ -0,0 +1,90 @@
+---
+source: crates/biome_cli/tests/snap_test.rs
+expression: redactor(content)
+---
+## `workspace/biome.json`
+
+```json
+{
+  "vcs": {
+    "enabled": true,
+    "clientKind": "git",
+    "useIgnoreFile": true,
+    "root": ".."
+  }
+}
+```
+
+## `.gitignore`
+
+```gitignore
+**/file2.js
+
+```
+
+## `workspace/file1.js`
+
+```js
+  statement(  )  
+```
+
+## `workspace/file2.js`
+
+```js
+  statement(  )  
+```
+
+# Termination Message
+
+```block
+format ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
+
+  × Some errors were emitted while running checks.
+  
+
+
+```
+
+# Emitted Messages
+
+```block
+biome.json format ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
+
+  × Formatter would have printed the following content:
+  
+    1 1 │   {
+    2   │ - ············"vcs":·{
+    3   │ - ················"enabled":·true,
+    4   │ - ················"clientKind":·"git",
+    5   │ - ················"useIgnoreFile":·true,
+    6   │ - ················"root":·".."
+    7   │ - ············}
+    8   │ - ········}
+      2 │ + → "vcs":·{
+      3 │ + → → "enabled":·true,
+      4 │ + → → "clientKind":·"git",
+      5 │ + → → "useIgnoreFile":·true,
+      6 │ + → → "root":·".."
+      7 │ + → }
+      8 │ + }
+      9 │ + 
+  
+
+```
+
+```block
+file1.js format ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
+
+  × Formatter would have printed the following content:
+  
+    1   │ - ··statement(··)··
+      1 │ + statement();
+      2 │ + 
+  
+
+```
+
+```block
+Checked 2 files in <TIME>. No fixes applied.
+Found 2 errors.
+```

crates/biome_cli/tests/snapshots/main_commands_migrate/should_migrate_jsonc_with_config_path.snap

@@ -5,14 +5,14 @@ expression: redactor(content)
 ## `base.biome.jsonc`
 
 ```jsonc
-
-    // this is another comment
-    {
-    // this is a comment
-    "organizeImports": {
-        "enabled": true
-    }
+// this is another comment
+{
+	// this is a comment
+	"root": false,
+	// this is a comment
+	"assist": { "actions": { "source": { "organizeImports": "on" } } }
 }
+
 ```
 
 # Emitted Messages

crates/biome_fs/src/fs/os.rs

@@ -490,7 +490,8 @@ impl TemporaryFs {
     /// will be stripped of the working directory path, making snapshots predictable.
     pub fn create_mem(&self) -> MemoryFileSystem {
         let fs = MemoryFileSystem::default();
-        for (path, content) in self.files.iter() {
+        for (path, _) in self.files.iter() {
+            let content = fs::read_to_string(path.as_std_path()).expect("File to exist");
             fs.insert(
                 path.clone()
                     .strip_prefix(self.project_directory.as_str())

crates/biome_service/src/workspace/server.rs

@@ -46,7 +46,7 @@ use biome_diagnostics::{
     Diagnostic, DiagnosticExt, Severity, serde::Diagnostic as SerdeDiagnostic,
 };
 use biome_formatter::Printed;
-use biome_fs::{BiomePath, ConfigName, PathKind};
+use biome_fs::{BiomePath, ConfigName, PathKind, normalize_path};
 use biome_grit_patterns::{CompilePatternOptions, GritQuery, compile_pattern_with_options};
 use biome_html_syntax::HtmlRoot;
 use biome_js_syntax::{AnyJsRoot, LanguageVariant, ModuleKind};
@@ -1240,7 +1240,11 @@ impl Workspace for WorkspaceServer {
         } else {
             // If the configuration is a root one, we also load the ignore files
             if settings.is_vcs_enabled() && settings.vcs_settings.should_use_ignore_file() {
-                let directory = workspace_directory.unwrap_or_default();
+                let directory = settings
+                    .vcs_settings
+                    .to_base_path(workspace_directory.as_deref())
+                    .map(|p| normalize_path(&p))
+                    .unwrap_or_default();
                 match settings.vcs_settings.client_kind {
                     None => {}
                     Some(VcsClientKind::Git) => {