refactor(env): split and join PATH lists with std::env

The shim's PATH_SEPARATOR was hardcoded to ":", so every PATH list was
split and joined on the wrong character off Unix. std::env::split_paths
and join_paths use the platform's separator, which also lets the bin-dir
membership test in EventDispatcher compare list entries instead of
regex-matching the raw PATH string.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

4 files changed, 24 insertions, 22 deletions

diff --git a/crates/shirabe-external-packages/src/symfony/process/executable_finder.rs b/crates/shirabe-external-packages/src/symfony/process/executable_finder.rs
index 309cdf7e..5b1c0994 100644
--- a/crates/shirabe-external-packages/src/symfony/process/executable_finder.rs
+++ b/crates/shirabe-external-packages/src/symfony/process/executable_finder.rs
@@ -33,7 +33,9 @@ impl ExecutableFinder {
             .or_else(|| shirabe_php_shim::getenv("Path"))
             .map(|v| v.to_string_lossy().into_owned())
             .unwrap_or_default();
-        let mut dirs = shirabe_php_shim::explode(shirabe_php_shim::PATH_SEPARATOR, &path);
+        let mut dirs: Vec<String> = std::env::split_paths(&path)
+            .map(|dir| dir.into_os_string().into_string().unwrap())
+            .collect();
         dirs.extend_from_slice(extra_dirs);
 
         let mut suffixes: Vec<String> = vec![];
@@ -42,9 +44,9 @@ impl ExecutableFinder {
                 shirabe_php_shim::getenv("PATHEXT").map(|v| v.to_string_lossy().into_owned());
             suffixes = self.suffixes.clone();
             let exts = match path_ext {
-                Some(ref ext) if !ext.is_empty() => {
-                    shirabe_php_shim::explode(shirabe_php_shim::PATH_SEPARATOR, ext)
-                }
+                Some(ref ext) if !ext.is_empty() => std::env::split_paths(ext)
+                    .map(|e| e.into_os_string().into_string().unwrap())
+                    .collect(),
                 _ => vec![
                     ".exe".to_string(),
                     ".bat".to_string(),
diff --git a/crates/shirabe-php-shim/src/fs.rs b/crates/shirabe-php-shim/src/fs.rs
index 575ce26a..7a8114bb 100644
--- a/crates/shirabe-php-shim/src/fs.rs
+++ b/crates/shirabe-php-shim/src/fs.rs
@@ -19,8 +19,6 @@ pub const PATHINFO_EXTENSION: i64 = 4;
 pub const PATHINFO_DIRNAME: i64 = 1;
 pub const PATHINFO_BASENAME: i64 = 2;
 
-pub const PATH_SEPARATOR: &str = ":";
-
 /// PHP `PHP_MAXPATHLEN`: the platform's `MAXPATHLEN` (`MAX_PATH` on Windows).
 pub const PHP_MAXPATHLEN: i64 = if cfg!(windows) {
     260
diff --git a/crates/shirabe/src/event_dispatcher/event_dispatcher.rs b/crates/shirabe/src/event_dispatcher/event_dispatcher.rs
index 3db924d4..f037f87d 100644
--- a/crates/shirabe/src/event_dispatcher/event_dispatcher.rs
+++ b/crates/shirabe/src/event_dispatcher/event_dispatcher.rs
@@ -31,7 +31,7 @@ use shirabe_php_rpc::{
 };
 use shirabe_php_shim::Catch as _;
 use shirabe_php_shim::{
-    InvalidArgumentException, PATH_SEPARATOR, PhpMixed, RuntimeException, array_pop, array_push,
+    InvalidArgumentException, PhpMixed, RuntimeException, array_pop, array_push,
     array_search_in_vec, array_splice, file_exists, get_class, hash, implode, ini_get, is_array,
     is_callable, is_object, is_string, krsort, php_regex, preg_quote, realpath,
     spl_autoload_functions, spl_autoload_register, spl_autoload_unregister, spl_object_hash,
@@ -1413,19 +1413,16 @@ try {{
         if shirabe_php_shim::is_dir(&bin_dir) {
             let bin_dir = realpath(&bin_dir).unwrap_or(bin_dir);
             let path_value = Platform::get_env(path_env).unwrap_or_default();
-            if !Preg::is_match(
-                format!(
-                    "{{(^|{}){}($|{})}}",
-                    PATH_SEPARATOR,
-                    preg_quote(&bin_dir, None),
-                    PATH_SEPARATOR
-                ),
-                &path_value,
-            ) {
-                Platform::put_env(
-                    path_env,
-                    &format!("{}{}{}", bin_dir, PATH_SEPARATOR, path_value),
-                );
+            if !std::env::split_paths(&path_value).any(|dir| dir == std::path::Path::new(&bin_dir))
+            {
+                let path_value = std::env::join_paths(
+                    std::iter::once(std::path::PathBuf::from(&bin_dir))
+                        .chain(std::env::split_paths(&path_value)),
+                )
+                .expect("bin-dir holds no path separator")
+                .into_string()
+                .unwrap();
+                Platform::put_env(path_env, &path_value);
             }
         }
     }
diff --git a/crates/shirabe/tests/util/ini_helper_test.rs b/crates/shirabe/tests/util/ini_helper_test.rs
index 0b3835a0..90015169 100644
--- a/crates/shirabe/tests/util/ini_helper_test.rs
+++ b/crates/shirabe/tests/util/ini_helper_test.rs
@@ -2,7 +2,7 @@
 
 use shirabe::util::ini_helper::IniHelper;
 use shirabe::util::platform::Platform;
-use shirabe_php_shim::{PATH_SEPARATOR, getenv, putenv};
+use shirabe_php_shim::{getenv, putenv};
 
 #[allow(dead_code)]
 fn set_up() -> TearDown {
@@ -39,7 +39,12 @@ impl Drop for TearDown {
 }
 
 fn set_env(paths: &[&str]) {
-    unsafe { putenv("COMPOSER_ORIGINAL_INIS", paths.join(PATH_SEPARATOR)) };
+    unsafe {
+        putenv(
+            "COMPOSER_ORIGINAL_INIS",
+            std::env::join_paths(paths).unwrap(),
+        )
+    };
 }
 
 #[test]