Isolate dependency installs from inherited Git repository state

crates/prek/src/languages/bun/bun.rs

@@ -7,6 +7,7 @@ use prek_consts::prepend_paths;
 use tracing::debug;
 
 use crate::cli::reporter::HookInstallReporter;
+use crate::git::GitCommandExt;
 use crate::hook::InstalledHook;
 use crate::hook::{Hook, InstallInfo};
 use crate::languages::bun::BunRequest;
@@ -83,6 +84,7 @@ impl LanguageBackend for Bun {
                 .args(deps)
                 .env(EnvVars::PATH, new_path)
                 .env(EnvVars::BUN_INSTALL, &info.env_path)
+                .isolate_from_git_env()
                 .check(true)
                 .output()
                 .await?;

crates/prek/src/languages/dart.rs

@@ -23,6 +23,7 @@ use serde::{Deserialize, Serialize};
 use tracing::debug;
 
 use crate::cli::reporter::HookInstallReporter;
+use crate::git::GitCommandExt;
 use crate::hook::{Hook, InstallInfo, InstalledHook};
 use crate::hook_entry::PreparedHookEntry;
 use crate::languages::{ExecutionEnvironment, LanguageBackend};
@@ -351,6 +352,7 @@ async fn install_package_config(
         .env(EnvVars::PUB_CACHE, env_path)
         .arg("pub")
         .arg("get")
+        .isolate_from_git_env()
         .check(true)
         .output()
         .await?;

crates/prek/src/languages/haskell.rs

@@ -7,6 +7,7 @@ use prek_consts::prepend_paths;
 use tracing::debug;
 
 use crate::cli::reporter::HookInstallReporter;
+use crate::git::GitCommandExt;
 use crate::hook::{Hook, InstallInfo, InstalledHook};
 use crate::languages::{ExecutionEnvironment, LanguageBackend};
 use crate::process::Cmd;
@@ -86,6 +87,7 @@ impl LanguageBackend for Haskell {
             .arg("--installdir")
             .arg(&bin_dir)
             .args(pkgs)
+            .isolate_from_git_env()
             .check(true)
             .output()
             .await

crates/prek/src/languages/julia.rs

@@ -7,6 +7,7 @@ use tracing::debug;
 
 use crate::cli::reporter::HookInstallReporter;
 use crate::cli::run::HookRunReporter;
+use crate::git::GitCommandExt;
 use crate::hook::{Hook, InstallInfo, InstalledHook};
 use crate::languages::LanguageBackend;
 use crate::process::Cmd;
@@ -70,6 +71,7 @@ impl LanguageBackend for Julia {
             .arg(julia_code)
             .arg("--")
             .args(&hook.additional_dependencies)
+            .isolate_from_git_env()
             .check(true)
             .output()
             .await

crates/prek/src/languages/node/node.rs

@@ -11,6 +11,7 @@ use tracing::debug;
 use url::Url;
 
 use crate::cli::reporter::HookInstallReporter;
+use crate::git::GitCommandExt;
 use crate::hook::InstalledHook;
 use crate::hook::{Hook, InstallInfo};
 use crate::languages::node::NodeRequest;
@@ -341,7 +342,8 @@ impl Npm<'_> {
 
     fn command(&self) -> Cmd {
         let mut cmd = Cmd::new(self.executable);
-        cmd.env(EnvVars::PATH, self.path)
+        cmd.isolate_from_git_env()
+            .env(EnvVars::PATH, self.path)
             .env(EnvVars::NODE_PATH, self.node_path);
         for key in NPM_CONFIG_ENVS_TO_REMOVE {
             cmd.env_remove(key);

crates/prek/src/languages/php.rs

@@ -11,6 +11,7 @@ use serde_json::{Map, Value, json};
 use tracing::debug;
 
 use crate::cli::reporter::HookInstallReporter;
+use crate::git::GitCommandExt;
 use crate::hook::{Hook, InstallInfo, InstalledHook};
 use crate::languages::{ExecutionEnvironment, LanguageBackend};
 use crate::process::Cmd;
@@ -193,6 +194,7 @@ impl LanguageBackend for Php {
                 .arg("--no-progress")
                 .arg("--")
                 .args(dependencies)
+                .isolate_from_git_env()
                 .check(true)
                 .output()
                 .await

crates/prek/src/languages/swift.rs

@@ -8,6 +8,7 @@ use semver::Version;
 use tracing::debug;
 
 use crate::cli::reporter::HookInstallReporter;
+use crate::git::GitCommandExt;
 use crate::hook::{Hook, InstallInfo, InstalledHook};
 use crate::languages::{ExecutionEnvironment, LanguageBackend};
 use crate::process::Cmd;
@@ -113,6 +114,7 @@ impl LanguageBackend for Swift {
                     .arg(repo_path)
                     .arg("--build-path")
                     .arg(&build_path)
+                    .isolate_from_git_env()
                     .check(true)
                     .output()
                     .await
@@ -128,6 +130,7 @@ impl LanguageBackend for Swift {
                     .arg("--build-path")
                     .arg(&build_path)
                     .arg("--show-bin-path")
+                    .isolate_from_git_env()
                     .check(true)
                     .output()
                     .await

crates/prek/tests/languages/node.rs

@@ -1,9 +1,10 @@
+use assert_cmd::assert::OutputAssertExt;
 use assert_fs::assert::PathAssert;
 use assert_fs::fixture::{FileWriteStr, PathChild, PathCreateDir};
 use prek_consts::PRE_COMMIT_HOOKS_YAML;
 use prek_consts::env_vars::{EnvVars, EnvVarsRead};
 
-use crate::common::{TestContext, cmd_snapshot, make_executable, remove_bin_from_path};
+use crate::common::{TestContext, cmd_snapshot, git_cmd, make_executable, remove_bin_from_path};
 
 #[test]
 fn exec_uses_installed_node_environment() -> anyhow::Result<()> {
@@ -584,3 +585,82 @@ fn npm_version() {
     ----- stderr -----
     ");
 }
+
+#[test]
+fn node_install_does_not_modify_inherited_git_index() -> anyhow::Result<()> {
+    let hook_repo = TestContext::new();
+    hook_repo.init_project();
+
+    hook_repo
+        .work_dir()
+        .child("package.json")
+        .write_str(indoc::indoc! {r#"
+        {
+          "name": "sentinel-node-tool",
+          "version": "1.0.0",
+          "bin": {
+            "sentinel-node-tool": "cli.js"
+          }
+        }
+    "#})?;
+    let cli = hook_repo.work_dir().child("cli.js");
+    cli.write_str(indoc::indoc! {r#"
+        #!/usr/bin/env node
+        console.log("sentinel node ok");
+    "#})?;
+    make_executable(cli.path())?;
+    hook_repo
+        .work_dir()
+        .child(PRE_COMMIT_HOOKS_YAML)
+        .write_str(indoc::indoc! {r"
+        - id: sentinel-node
+          name: sentinel-node
+          entry: sentinel-node-tool
+          language: node
+          always_run: true
+          pass_filenames: false
+    "})?;
+
+    hook_repo.git_add(".");
+    hook_repo.git_commit("Add sentinel Node hook");
+    hook_repo.git_tag("v1.0.0");
+
+    let context = TestContext::new();
+    context.init_project();
+    context.write_pre_commit_config(&indoc::formatdoc! {r"
+        repos:
+          - repo: {repo}
+            rev: v1.0.0
+            hooks:
+              - id: sentinel-node
+    ", repo = hook_repo.work_dir().display()});
+    context.git_add(".");
+
+    let staged_before = git_cmd(context.work_dir())
+        .args(["ls-files", "--stage"])
+        .assert()
+        .success()
+        .get_output()
+        .stdout
+        .clone();
+
+    let git_dir = context.work_dir().child(".git");
+    context
+        .run()
+        .arg("--all-files")
+        .env(EnvVars::GIT_DIR, git_dir.path())
+        .env("GIT_INDEX_FILE", git_dir.child("index").path())
+        .assert()
+        .success();
+
+    let staged_after = git_cmd(context.work_dir())
+        .args(["ls-files", "--stage"])
+        .assert()
+        .success()
+        .get_output()
+        .stdout
+        .clone();
+    assert_eq!(staged_after, staged_before);
+
+    Ok(())
+}