fix(dependency-resolver): query real PHP for ext-* version/loaded checks

Two shim gaps made the extension-related branches of solver-problem
messages wrong:

- phpversion($ext) with a non-empty extension can't be known statically
  (it's shirabe-php-shim's todo!()); Problem::get_missing_package_reason
  now calls shirabe_php_rpc::phpversion, the same RPC bridge
  platform::runtime::Runtime::get_extension_version already uses.
- extension_loaded's hardcoded allowlist was missing "pcre", a mandatory
  always-compiled-in PHP extension, so ext-pcre was misreported as
  "missing from your system" instead of "disabled by your platform
  config" whenever a platform override disabled it.

Also fix XdebugHandler::getAllIniFiles() always returning `[""]`
(a php-runtime stub): create_extension_hint()'s early-return guard
(`paths[0] empty && len==1`) fired unconditionally, silently dropping
the entire "To enable extensions..." hint from every solver-problem
message that mentions missing extensions. shirabe-external-packages
can't depend on shirabe-php-rpc (shirabe-php-rpc already depends on
shirabe-external-packages), so IniHelper::get_all() queries a new
get_all_ini_files RPC command directly instead of going through the
stub.

This exposed that XdebugHandler is never constructed with a name
because bin/composer's restart-without-Xdebug bootstrap was never
ported to main.rs, making COMPOSER_ORIGINAL_INIS-driven behavior
unreachable; documented with a TODO(phase-c) and updated
ini_helper_test.rs's ignore reasons (and ignored test_with_no_ini,
which only passed before by coincidence with the old stub's constant
output) to match.

9 files changed, 66 insertions, 22 deletions

diff --git a/crates/shirabe-external-packages/src/composer/xdebug_handler/xdebug_handler.rs b/crates/shirabe-external-packages/src/composer/xdebug_handler/xdebug_handler.rs
index 01f8eb78..3bbe9014 100644
--- a/crates/shirabe-external-packages/src/composer/xdebug_handler/xdebug_handler.rs
+++ b/crates/shirabe-external-packages/src/composer/xdebug_handler/xdebug_handler.rs
@@ -19,10 +19,16 @@ impl XdebugHandler {
 
     pub fn get_all_ini_files() -> Vec<String> {
         // TODO(php-runtime)
-        // No XdebugHandler is ever constructed (`self::$name` stays null) so the
-        // COMPOSER_ORIG_INIS env lookup is skipped, and without a PHP runtime
-        // `php_ini_loaded_file()` is `false` and `php_ini_scanned_files()` is `false`,
-        // so PHP would return `[(string) false]` = `[""]`.
+        // No XdebugHandler is ever constructed (`self::$name` stays null), because the
+        // `new XdebugHandler('Composer'); $xdebug->check();` bootstrap in `bin/composer` is not
+        // ported (see the TODO(phase-c) at the top of shirabe's main.rs), so the
+        // COMPOSER_ORIGINAL_INIS env-var branch is unreachable here.
+        //
+        // shirabe-external-packages cannot depend on shirabe-php-rpc (the reverse dependency
+        // would cycle, since shirabe-php-rpc already depends on shirabe-external-packages), so
+        // callers that need the real PHP runtime's ini files (php_ini_loaded_file() /
+        // php_ini_scanned_files()) query shirabe_php_rpc directly instead of going through this
+        // stub; see crate::util::ini_helper::IniHelper::get_all.
         vec![String::new()]
     }
 }
diff --git a/crates/shirabe-php-rpc/php/worker.php b/crates/shirabe-php-rpc/php/worker.php
index d7d8f251..060373d5 100644
--- a/crates/shirabe-php-rpc/php/worker.php
+++ b/crates/shirabe-php-rpc/php/worker.php
@@ -13,6 +13,14 @@ $dispatch = [
     'curl_version' => static fn($arg) => function_exists('curl_version') ? (curl_version()['version'] ?? null) : null,
     'phpversion' => static fn($name) => phpversion($name),
     'get_loaded_extensions' => static fn($arg) => implode(',', get_loaded_extensions()),
+    'get_all_ini_files' => static function ($arg) {
+        $paths = [(string) php_ini_loaded_file()];
+        $scanned = php_ini_scanned_files();
+        if ($scanned !== false) {
+            $paths = array_merge($paths, array_map('trim', explode(',', $scanned)));
+        }
+        return implode(',', $paths);
+    },
     'extension_info' => static function ($name) {
         if (!extension_loaded($name)) {
             return '';
diff --git a/crates/shirabe-php-rpc/src/lib.rs b/crates/shirabe-php-rpc/src/lib.rs
index d939829a..dde91d3c 100644
--- a/crates/shirabe-php-rpc/src/lib.rs
+++ b/crates/shirabe-php-rpc/src/lib.rs
@@ -88,6 +88,18 @@ pub fn get_loaded_extensions() -> Vec<String> {
     }
 }
 
+/// `Composer\XdebugHandler\XdebugHandler::getAllIniFiles()` (minus the `self::$name` branch,
+/// which is unreachable since this port never constructs an XdebugHandler): `[(string)
+/// php_ini_loaded_file()]` merged with the trimmed, comma-split `php_ini_scanned_files()` list
+/// when scanning is active. Paths are joined with `,` on the PHP side and split back here; real
+/// ini paths never contain a comma (same assumption `get_loaded_extensions` makes).
+pub fn get_all_ini_files() -> Vec<String> {
+    match call("get_all_ini_files", "") {
+        PhpMixed::String(s) => s.split(',').map(|s| s.to_string()).collect(),
+        other => panic!("PHP RPC: `get_all_ini_files` did not return a string: {other:?}"),
+    }
+}
+
 const GLUE_SCRIPT: &str = include_str!("../php/worker.php");
 
 struct Worker {
diff --git a/crates/shirabe-php-shim/src/runtime.rs b/crates/shirabe-php-shim/src/runtime.rs
index fa7a728c..c4bd62c9 100644
--- a/crates/shirabe-php-shim/src/runtime.rs
+++ b/crates/shirabe-php-shim/src/runtime.rs
@@ -162,6 +162,7 @@ pub fn extension_loaded(name: &str) -> bool {
             | "intl"
             | "mbstring"
             | "openssl"
+            | "pcre"
             | "zip"
             | "zlib"
     )
diff --git a/crates/shirabe/src/dependency_resolver/problem.rs b/crates/shirabe/src/dependency_resolver/problem.rs
index 855638cf..5ff949a9 100644
--- a/crates/shirabe/src/dependency_resolver/problem.rs
+++ b/crates/shirabe/src/dependency_resolver/problem.rs
@@ -459,7 +459,9 @@ impl Problem {
                     Self::constraint_to_text(constraint)
                 );
 
-                let runtime_version = phpversion(&ext);
+                // Per-extension version info can't be known statically; query the real PHP
+                // runtime via the RPC bridge, same as platform::runtime::Runtime::get_extension_version.
+                let runtime_version = shirabe_php_rpc::phpversion(&ext);
                 let effective_version = match runtime_version {
                     None => "0".to_string(),
                     Some(ref v) => v.clone(),
diff --git a/crates/shirabe/src/main.rs b/crates/shirabe/src/main.rs
index 2ae6d903..6eb8e4cb 100644
--- a/crates/shirabe/src/main.rs
+++ b/crates/shirabe/src/main.rs
@@ -3,6 +3,13 @@
 use shirabe_php_shim::{PHP_ENV, PHP_SERVER};
 
 fn main() {
+    // TODO(phase-c): PHP: `$xdebug = new XdebugHandler('Composer'); $xdebug->check(); unset($xdebug);`
+    // (restart the process without Xdebug loaded, for performance) is not ported. Since no
+    // XdebugHandler is ever constructed, `self::$name` never gets set, so the
+    // COMPOSER_ORIGINAL_INIS-env-var branch of XdebugHandler::getAllIniFiles() (see
+    // shirabe-external-packages' xdebug_handler.rs and shirabe/src/util/ini_helper.rs) is
+    // unreachable in this port, not merely unexercised by current tests.
+
     // Take the $_ENV / $_SERVER snapshots before any putenv() mutates the real environment.
     // See `docs/dev/env-vars-porting.md` for details.
     std::sync::LazyLock::force(&PHP_ENV);
diff --git a/crates/shirabe/src/util/ini_helper.rs b/crates/shirabe/src/util/ini_helper.rs
index 57894113..c36b9189 100644
--- a/crates/shirabe/src/util/ini_helper.rs
+++ b/crates/shirabe/src/util/ini_helper.rs
@@ -1,13 +1,15 @@
 //! ref: composer/src/Composer/Util/IniHelper.php
 
-use shirabe_external_packages::composer::xdebug_handler::XdebugHandler;
-
 pub struct IniHelper;
 
 impl IniHelper {
     /// Returns an array of php.ini locations with at least one entry.
     pub fn get_all() -> Vec<String> {
-        XdebugHandler::get_all_ini_files()
+        // PHP: XdebugHandler::getAllIniFiles(). shirabe_external_packages::XdebugHandler's port
+        // of that method can't reach the PHP RPC bridge (shirabe-php-rpc already depends on
+        // shirabe-external-packages, so the reverse dependency would cycle), so query the real
+        // PHP runtime's loaded/scanned ini files here instead.
+        shirabe_php_rpc::get_all_ini_files()
     }
 
     /// Describes the location of the loaded php.ini file(s).
diff --git a/crates/shirabe/tests/installer_test.rs b/crates/shirabe/tests/installer_test.rs
index 1e25646b..311fbb12 100644
--- a/crates/shirabe/tests/installer_test.rs
+++ b/crates/shirabe/tests/installer_test.rs
@@ -1396,7 +1396,7 @@ pool_optimizer_test! {
     pool_optimizer_install_without_lock => "install-without-lock.test";
     pool_optimizer_load_replaced_package_if_replacer_dropped => "load-replaced-package-if-replacer-dropped.test";
     pool_optimizer_outdated_lock_file_fails_install => "outdated-lock-file-fails-install.test";
-    pool_optimizer_outdated_lock_file_with_new_platform_reqs_fails => "outdated-lock-file-with-new-platform-reqs-fails.test", ignore = "TODO(phase-d): known-failing fixture under COMPOSER_POOL_OPTIMIZER=1";
+    pool_optimizer_outdated_lock_file_with_new_platform_reqs_fails => "outdated-lock-file-with-new-platform-reqs-fails.test";
     pool_optimizer_partial_update_always_updates_symlinked_path_repos => "partial-update-always-updates-symlinked-path-repos.test", ignore = "TODO(phase-d): known-failing fixture under COMPOSER_POOL_OPTIMIZER=1";
     pool_optimizer_partial_update_downgrades_non_allow_listed_unstable => "partial-update-downgrades-non-allow-listed-unstable.test";
     pool_optimizer_partial_update_forces_dev_reference_from_lock_for_non_updated_packages => "partial-update-forces-dev-reference-from-lock-for-non-updated-packages.test", ignore = "TODO(phase-d): known-failing fixture under COMPOSER_POOL_OPTIMIZER=1";
@@ -1413,7 +1413,7 @@ pool_optimizer_test! {
     pool_optimizer_partial_update_with_deps_warns_root => "partial-update-with-deps-warns-root.test";
     pool_optimizer_partial_update_with_symlinked_path_repos => "partial-update-with-symlinked-path-repos.test", ignore = "TODO(phase-d): known-failing fixture under COMPOSER_POOL_OPTIMIZER=1";
     pool_optimizer_partial_update_without_lock => "partial-update-without-lock.test";
-    pool_optimizer_platform_ext_solver_problems => "platform-ext-solver-problems.test", ignore = "TODO(phase-d): known-failing fixture under COMPOSER_POOL_OPTIMIZER=1";
+    pool_optimizer_platform_ext_solver_problems => "platform-ext-solver-problems.test";
     pool_optimizer_plugins_are_installed_first => "plugins-are-installed-first.test";
     pool_optimizer_prefer_lowest_branches => "prefer-lowest-branches.test";
     pool_optimizer_problems_reduce_versions => "problems-reduce-versions.test";
@@ -1447,8 +1447,8 @@ pool_optimizer_test! {
     pool_optimizer_root_alias_gets_loaded_for_locked_pkgs => "root-alias-gets-loaded-for-locked-pkgs.test";
     pool_optimizer_root_requirements_do_not_affect_locked_versions => "root-requirements-do-not-affect-locked-versions.test";
     pool_optimizer_solver_problem_with_hash_in_branch => "solver-problem-with-hash-in-branch.test";
-    pool_optimizer_solver_problems_with_disabled_platform => "solver-problems-with-disabled-platform.test", ignore = "TODO(phase-d): known-failing fixture under COMPOSER_POOL_OPTIMIZER=1";
-    pool_optimizer_solver_problems => "solver-problems.test", ignore = "TODO(phase-d): known-failing fixture under COMPOSER_POOL_OPTIMIZER=1";
+    pool_optimizer_solver_problems_with_disabled_platform => "solver-problems-with-disabled-platform.test";
+    pool_optimizer_solver_problems => "solver-problems.test";
     pool_optimizer_suggest_installed => "suggest-installed.test";
     pool_optimizer_suggest_prod_nolock => "suggest-prod-nolock.test";
     pool_optimizer_suggest_prod => "suggest-prod.test";
@@ -1586,7 +1586,7 @@ raw_pool_test! {
     raw_pool_install_without_lock => "install-without-lock.test";
     raw_pool_load_replaced_package_if_replacer_dropped => "load-replaced-package-if-replacer-dropped.test";
     raw_pool_outdated_lock_file_fails_install => "outdated-lock-file-fails-install.test";
-    raw_pool_outdated_lock_file_with_new_platform_reqs_fails => "outdated-lock-file-with-new-platform-reqs-fails.test", ignore = "TODO(phase-d): known-failing fixture under COMPOSER_POOL_OPTIMIZER=0";
+    raw_pool_outdated_lock_file_with_new_platform_reqs_fails => "outdated-lock-file-with-new-platform-reqs-fails.test";
     raw_pool_partial_update_always_updates_symlinked_path_repos => "partial-update-always-updates-symlinked-path-repos.test", ignore = "TODO(phase-d): known-failing fixture under COMPOSER_POOL_OPTIMIZER=0";
     raw_pool_partial_update_downgrades_non_allow_listed_unstable => "partial-update-downgrades-non-allow-listed-unstable.test";
     raw_pool_partial_update_forces_dev_reference_from_lock_for_non_updated_packages => "partial-update-forces-dev-reference-from-lock-for-non-updated-packages.test", ignore = "TODO(phase-d): known-failing fixture under COMPOSER_POOL_OPTIMIZER=0";
@@ -1603,7 +1603,7 @@ raw_pool_test! {
     raw_pool_partial_update_with_deps_warns_root => "partial-update-with-deps-warns-root.test";
     raw_pool_partial_update_with_symlinked_path_repos => "partial-update-with-symlinked-path-repos.test", ignore = "TODO(phase-d): known-failing fixture under COMPOSER_POOL_OPTIMIZER=0";
     raw_pool_partial_update_without_lock => "partial-update-without-lock.test";
-    raw_pool_platform_ext_solver_problems => "platform-ext-solver-problems.test", ignore = "TODO(phase-d): known-failing fixture under COMPOSER_POOL_OPTIMIZER=0";
+    raw_pool_platform_ext_solver_problems => "platform-ext-solver-problems.test";
     raw_pool_plugins_are_installed_first => "plugins-are-installed-first.test";
     raw_pool_prefer_lowest_branches => "prefer-lowest-branches.test";
     raw_pool_problems_reduce_versions => "problems-reduce-versions.test";
@@ -1637,8 +1637,8 @@ raw_pool_test! {
     raw_pool_root_alias_gets_loaded_for_locked_pkgs => "root-alias-gets-loaded-for-locked-pkgs.test";
     raw_pool_root_requirements_do_not_affect_locked_versions => "root-requirements-do-not-affect-locked-versions.test";
     raw_pool_solver_problem_with_hash_in_branch => "solver-problem-with-hash-in-branch.test";
-    raw_pool_solver_problems_with_disabled_platform => "solver-problems-with-disabled-platform.test", ignore = "TODO(phase-d): known-failing fixture under COMPOSER_POOL_OPTIMIZER=0";
-    raw_pool_solver_problems => "solver-problems.test", ignore = "TODO(phase-d): known-failing fixture under COMPOSER_POOL_OPTIMIZER=0";
+    raw_pool_solver_problems_with_disabled_platform => "solver-problems-with-disabled-platform.test";
+    raw_pool_solver_problems => "solver-problems.test";
     raw_pool_suggest_installed => "suggest-installed.test";
     raw_pool_suggest_prod_nolock => "suggest-prod-nolock.test";
     raw_pool_suggest_prod => "suggest-prod.test";
diff --git a/crates/shirabe/tests/util/ini_helper_test.rs b/crates/shirabe/tests/util/ini_helper_test.rs
index 76705a09..0b3835a0 100644
--- a/crates/shirabe/tests/util/ini_helper_test.rs
+++ b/crates/shirabe/tests/util/ini_helper_test.rs
@@ -43,6 +43,9 @@ fn set_env(paths: &[&str]) {
 }
 
 #[test]
+#[ignore = "XdebugHandler is never constructed with a name (the bin/composer restart-without-Xdebug \
+bootstrap is unported, see TODO(phase-c) in shirabe's main.rs), so IniHelper::get_all() queries \
+the real PHP runtime directly instead of consulting COMPOSER_ORIGINAL_INIS"]
 fn test_with_no_ini() {
     let paths = [""];
 
@@ -55,8 +58,9 @@ fn test_with_no_ini() {
 }
 
 #[test]
-#[ignore = "XdebugHandler::get_all_ini_files() is stubbed to always return [\"\"], ignoring \
-COMPOSER_ORIGINAL_INIS entirely"]
+#[ignore = "XdebugHandler is never constructed with a name (the bin/composer restart-without-Xdebug \
+bootstrap is unported, see TODO(phase-c) in shirabe's main.rs), so IniHelper::get_all() queries \
+the real PHP runtime directly instead of consulting COMPOSER_ORIGINAL_INIS"]
 fn test_with_loaded_ini_only() {
     let paths = ["loaded.ini"];
 
@@ -65,8 +69,9 @@ fn test_with_loaded_ini_only() {
 }
 
 #[test]
-#[ignore = "XdebugHandler::get_all_ini_files() is stubbed to always return [\"\"], ignoring \
-COMPOSER_ORIGINAL_INIS entirely"]
+#[ignore = "XdebugHandler is never constructed with a name (the bin/composer restart-without-Xdebug \
+bootstrap is unported, see TODO(phase-c) in shirabe's main.rs), so IniHelper::get_all() queries \
+the real PHP runtime directly instead of consulting COMPOSER_ORIGINAL_INIS"]
 fn test_with_loaded_ini_and_additional() {
     let paths = ["loaded.ini", "one.ini", "two.ini"];
 
@@ -79,8 +84,9 @@ fn test_with_loaded_ini_and_additional() {
 }
 
 #[test]
-#[ignore = "XdebugHandler::get_all_ini_files() is stubbed to always return [\"\"], ignoring \
-COMPOSER_ORIGINAL_INIS entirely"]
+#[ignore = "XdebugHandler is never constructed with a name (the bin/composer restart-without-Xdebug \
+bootstrap is unported, see TODO(phase-c) in shirabe's main.rs), so IniHelper::get_all() queries \
+the real PHP runtime directly instead of consulting COMPOSER_ORIGINAL_INIS"]
 fn test_without_loaded_ini_and_additional() {
     let paths = ["", "one.ini", "two.ini"];