fix: determinate mapping (#172)

Signed-off-by: tison <wander4096@gmail.com>

fmt/src/config/mod.rs

@@ -108,7 +108,7 @@ impl FeatureGate {
     }
 }
 
-#[derive(Debug, Clone, Eq, PartialEq)]
+#[derive(Debug, Clone)]
 pub enum Mapping {
     Filename {
         pattern: String,
@@ -120,6 +120,22 @@ pub enum Mapping {
     },
 }
 
+impl PartialEq for Mapping {
+    fn eq(&self, other: &Self) -> bool {
+        match (self, other) {
+            (Mapping::Filename { pattern: p1, .. }, Mapping::Filename { pattern: p2, .. }) => {
+                p1 == p2
+            }
+            (Mapping::Extension { pattern: p1, .. }, Mapping::Extension { pattern: p2, .. }) => {
+                p1 == p2
+            }
+            _ => false,
+        }
+    }
+}
+
+impl Eq for Mapping {}
+
 impl Hash for Mapping {
     fn hash<H: Hasher>(&self, state: &mut H) {
         state.write(match self {

fmt/src/processor.rs

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+use std::collections::hash_map::Entry;
 use std::collections::HashMap;
 use std::fs;
 use std::path::Path;
@@ -84,9 +85,11 @@ pub fn check_license_header<C: Callback>(
         if config.use_default_mapping {
             let default_mapping = default_mapping();
             for m in default_mapping {
-                if !mapping.contains(&m) {
-                    mapping.insert(m);
+                if let Some(o) = mapping.get(&m) {
+                    log::warn!("default mapping {m:?} is override by {o:?}");
+                    continue;
                 }
+                mapping.insert(m);
             }
         }
         mapping
@@ -95,20 +98,30 @@ pub fn check_license_header<C: Callback>(
     let definitions = {
         let mut defs = HashMap::new();
         for (k, v) in default_headers() {
-            if defs.contains_key(&k) {
-                anyhow::bail!("Header definition {k} is defined more than once");
+            match defs.entry(k) {
+                Entry::Occupied(mut ent) => {
+                    log::warn!("Default header {} is override", ent.key());
+                    ent.insert(v);
+                }
+                Entry::Vacant(ent) => {
+                    ent.insert(v);
+                }
             }
-            defs.insert(k, v);
         }
         for additional_header in &config.additional_headers {
             let additional_defs = fs::read_to_string(additional_header)
                 .with_context(|| format!("cannot load header definitions: {additional_header}"))
                 .and_then(deserialize_header_definitions)?;
             for (k, v) in additional_defs {
-                if defs.contains_key(&k) {
-                    anyhow::bail!("Header definition {k} is defined more than once");
+                match defs.entry(k) {
+                    Entry::Occupied(mut ent) => {
+                        log::warn!("Additional header {} is override", ent.key());
+                        ent.insert(v);
+                    }
+                    Entry::Vacant(ent) => {
+                        ent.insert(v);
+                    }
                 }
-                defs.insert(k, v);
             }
         }
         defs