Extract Decoder::entry_unless_proc_macro()

src/librustc_metadata/decoder.rs

@@ -450,11 +450,19 @@ impl<'a, 'tcx> CrateMetadata {
     pub fn is_proc_macro_crate(&self) -> bool {
         self.root.proc_macro_decls_static.is_some()
     }
+
     fn is_proc_macro(&self, id: DefIndex) -> bool {
         self.is_proc_macro_crate() &&
             self.root.proc_macro_data.unwrap().decode(self).find(|x| *x == id).is_some()
     }
 
+    fn entry_unless_proc_macro(&self, id: DefIndex) -> Option<Entry<'tcx>> {
+        match self.is_proc_macro(id) {
+            true => None,
+            false => Some(self.entry(id)),
+        }
+    }
+
     fn maybe_entry(&self, item_id: DefIndex) -> Option<Lazy<Entry<'tcx>>> {
         self.root.entries_index.lookup(self.blob.raw_bytes(), item_id)
     }
@@ -704,10 +712,8 @@ impl<'a, 'tcx> CrateMetadata {
     }
 
     pub fn get_deprecation(&self, id: DefIndex) -> Option<attr::Deprecation> {
-        match self.is_proc_macro(id) {
-            true => None,
-            false => self.entry(id).deprecation.map(|depr| depr.decode(self)),
-        }
+        self.entry_unless_proc_macro(id)
+            .and_then(|entry| entry.deprecation.map(|depr| depr.decode(self)))
     }
 
     pub fn get_visibility(&self, id: DefIndex) -> ty::Visibility {
@@ -918,31 +924,23 @@ impl<'a, 'tcx> CrateMetadata {
     }
 
     pub fn get_optimized_mir(&self, tcx: TyCtxt<'tcx>, id: DefIndex) -> Body<'tcx> {
-        let mir =
-            match self.is_proc_macro(id) {
-                true => None,
-                false => self.entry(id).mir.map(|mir| mir.decode((self, tcx))),
-            };
-
-        mir.unwrap_or_else(|| {
-            bug!("get_optimized_mir: missing MIR for `{:?}`", self.local_def_id(id))
-        })
+        self.entry_unless_proc_macro(id)
+            .and_then(|entry| entry.mir.map(|mir| mir.decode((self, tcx))))
+            .unwrap_or_else(|| {
+                bug!("get_optimized_mir: missing MIR for `{:?}", self.local_def_id(id))
+            })
     }
 
     pub fn get_promoted_mir(
         &self,
         tcx: TyCtxt<'tcx>,
         id: DefIndex,
     ) -> IndexVec<Promoted, Body<'tcx>> {
-        let promoted =
-            match self.is_proc_macro(id) {
-                true => None,
-                false => self.entry(id).promoted_mir.map(|promoted| promoted.decode((self, tcx)))
-            };
-
-        promoted.unwrap_or_else(|| {
-            bug!("get_promoted_mir: missing MIR for `{:?}`", self.local_def_id(id))
-        })
+        self.entry_unless_proc_macro(id)
+            .and_then(|entry| entry.promoted_mir.map(|promoted| promoted.decode((self, tcx))))
+            .unwrap_or_else(|| {
+                bug!("get_promoted_mir: missing MIR for `{:?}`", self.local_def_id(id))
+            })
     }
 
     pub fn mir_const_qualif(&self, id: DefIndex) -> u8 {