fix(symfony-finder): fail SplFileInfo::get_size on a failed stat

\SplFileInfo::getSize() throws a \RuntimeException when stat fails, and
neither Symfony's subclass nor Composer's Filesystem::directorySize()
catches it. Returning 0 turned an unreadable file into an empty one.

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

3 files changed, 12 insertions, 4 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 3861f168..0dfd1abf 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2257,6 +2257,7 @@ dependencies = [
 name = "shirabe-symfony-finder"
 version = "0.0.1"
 dependencies = [
+ "anyhow",
  "chrono",
  "indexmap",
  "regex",
diff --git a/crates/shirabe-symfony-finder/Cargo.toml b/crates/shirabe-symfony-finder/Cargo.toml
index 8088aa23..0823bfaf 100644
--- a/crates/shirabe-symfony-finder/Cargo.toml
+++ b/crates/shirabe-symfony-finder/Cargo.toml
@@ -10,6 +10,7 @@ license.workspace = true
 [dependencies]
 shirabe-pcre.workspace = true
 shirabe-php-shim.workspace = true
+anyhow.workspace = true
 chrono.workspace = true
 indexmap.workspace = true
 regex.workspace = true
diff --git a/crates/shirabe-symfony-finder/src/spl_file_info.rs b/crates/shirabe-symfony-finder/src/spl_file_info.rs
index b719efc5..40bd153a 100644
--- a/crates/shirabe-symfony-finder/src/spl_file_info.rs
+++ b/crates/shirabe-symfony-finder/src/spl_file_info.rs
@@ -76,9 +76,15 @@ impl SplFileInfo {
         shirabe_php_shim::realpath(&self.pathname)
     }
 
-    pub fn get_size(&self) -> i64 {
-        // \SplFileInfo::getSize() returns the file size in bytes (throws on failure).
-        // TODO(php-semantics): PHP throws a \RuntimeException on stat failure; this returns 0 instead.
-        shirabe_php_shim::filesize(&self.pathname).unwrap_or(0)
+    pub fn get_size(&self) -> anyhow::Result<i64> {
+        // Inherited from \SplFileInfo, whose failure message names the base class even for subclasses.
+        match shirabe_php_shim::filesize(&self.pathname) {
+            Some(size) => Ok(size),
+            None => Err(shirabe_php_shim::RuntimeException::new(format!(
+                "SplFileInfo::getSize(): stat failed for {}",
+                self.pathname
+            ))
+            .into()),
+        }
     }
 }