1 files changed, 30 insertions, 0 deletions
diff --git a/crates/shirabe/src/package/version/stability_filter.rs b/crates/shirabe/src/package/version/stability_filter.rs
index 6465a00..65f024f 100644
--- a/crates/shirabe/src/package/version/stability_filter.rs
+++ b/crates/shirabe/src/package/version/stability_filter.rs
@@ -1 +1,31 @@
 //! ref: composer/src/Composer/Package/Version/StabilityFilter.php
+
+use indexmap::IndexMap;
+use crate::package::base_package::BasePackage;
+
+pub struct StabilityFilter;
+
+impl StabilityFilter {
+    pub fn is_package_acceptable(
+        acceptable_stabilities: &IndexMap<String, i64>,
+        stability_flags: &IndexMap<String, i64>,
+        names: &[String],
+        stability: &str,
+    ) -> bool {
+        for name in names {
+            // allow if package matches the package-specific stability flag
+            if let Some(&flag) = stability_flags.get(name) {
+                if let Some(&stability_value) = BasePackage::STABILITIES.get(stability) {
+                    if stability_value <= flag {
+                        return true;
+                    }
+                }
+            } else if acceptable_stabilities.contains_key(stability) {
+                // allow if package matches the global stability requirement and has no exception
+                return true;
+            }
+        }
+
+        false
+    }
+}