store: use specialized class for store entries

We introduce two different classes for revlog and other entries. For now, we
still have multiple entry for the same revlog, but we will work toward grouping
the different file in a single entry in this series.

Having the distinction is a step toward this goal.

hgext/remotefilelog/remotefilelogserver.py

@@ -162,11 +162,8 b' def onetimesetup(ui):'
                             ):
                                 n = util.pconvert(fp[striplen:])
                                 d = store.decodedir(n)
-                                yield store.StoreEntry(
+                                yield store.SimpleStoreEntry(
                                     unencoded_path=d,
-                                    is_revlog=True,
-                                    revlog_type=None,
-                                    is_revlog_main=False,
                                     is_volatile=False,
                                     file_size=st.st_size,
                                 )

mercurial/store.py

@@ -454,15 +454,12 b' FILETYPE_OTHER = FILEFLAGS_OTHER'
 
 
 @attr.s(slots=True)
-class StoreEntry:
+class BaseStoreEntry:
     """An entry in the store
 
     This is returned by `store.walk` and represent some data in the store."""
 
     unencoded_path = attr.ib()
-    is_revlog = attr.ib(default=False)
-    revlog_type = attr.ib(default=None)
-    is_revlog_main = attr.ib(default=None)
     is_volatile = attr.ib(default=False)
     file_size = attr.ib(default=None)
 
@@ -477,6 +474,22 b' class StoreEntry:'
 
 
 @attr.s(slots=True)
+class SimpleStoreEntry(BaseStoreEntry):
+    """A generic entry in the store"""
+
+    is_revlog = False
+
+
+@attr.s(slots=True)
+class RevlogStoreEntry(BaseStoreEntry):
+    """A revlog entry in the store"""
+
+    is_revlog = True
+    revlog_type = attr.ib(default=None)
+    is_revlog_main = attr.ib(default=None)
+
+
+@attr.s(slots=True)
 class StoreFile:
     """a file matching an entry"""
 
@@ -536,7 +549,7 b' class basicstore:'
 
     def datafiles(
         self, matcher=None, undecodable=None
-    ) -> Generator[StoreEntry, None, None]:
+    ) -> Generator[BaseStoreEntry, None, None]:
         """Like walk, but excluding the changelog and root manifest.
 
         When [undecodable] is None, revlogs names that can't be
@@ -546,35 +559,42 b' class basicstore:'
         files = self._walk(b'data', True) + self._walk(b'meta', True)
         for (t, u, s) in files:
             if t is not None:
-                yield StoreEntry(
+                yield RevlogStoreEntry(
                     unencoded_path=u,
-                    is_revlog=True,
                     revlog_type=FILEFLAGS_FILELOG,
                     is_revlog_main=bool(t & FILEFLAGS_REVLOG_MAIN),
                     is_volatile=bool(t & FILEFLAGS_VOLATILE),
                     file_size=s,
                 )
 
-    def topfiles(self) -> Generator[StoreEntry, None, None]:
+    def topfiles(self) -> Generator[BaseStoreEntry, None, None]:
         # yield manifest before changelog
         files = reversed(self._walk(b'', False))
         for (t, u, s) in files:
             if u.startswith(b'00changelog'):
-                revlog_type = FILEFLAGS_CHANGELOG
-            elif u.startswith(b'00manifest'):
-                revlog_type = FILEFLAGS_MANIFESTLOG
-            else:
-                revlog_type = None
-            yield StoreEntry(
+                yield RevlogStoreEntry(
                 unencoded_path=u,
-                is_revlog=revlog_type is not None,
-                revlog_type=revlog_type,
+                    revlog_type=FILEFLAGS_CHANGELOG,
                 is_revlog_main=bool(t & FILEFLAGS_REVLOG_MAIN),
                 is_volatile=bool(t & FILEFLAGS_VOLATILE),
                 file_size=s,
             )
+            elif u.startswith(b'00manifest'):
+                yield RevlogStoreEntry(
+                    unencoded_path=u,
+                    revlog_type=FILEFLAGS_MANIFESTLOG,
+                    is_revlog_main=bool(t & FILEFLAGS_REVLOG_MAIN),
+                    is_volatile=bool(t & FILEFLAGS_VOLATILE),
+                    file_size=s,
+                )
+            else:
+                yield SimpleStoreEntry(
+                    unencoded_path=u,
+                    is_volatile=bool(t & FILEFLAGS_VOLATILE),
+                    file_size=s,
+                )
 
-    def walk(self, matcher=None) -> Generator[StoreEntry, None, None]:
+    def walk(self, matcher=None) -> Generator[BaseStoreEntry, None, None]:
         """return files related to data storage (ie: revlogs)
 
         yields (file_type, unencoded, size)
@@ -629,7 +649,7 b' class encodedstore(basicstore):'
 
     def datafiles(
         self, matcher=None, undecodable=None
-    ) -> Generator[StoreEntry, None, None]:
+    ) -> Generator[BaseStoreEntry, None, None]:
         for entry in super(encodedstore, self).datafiles():
             try:
                 f1 = entry.unencoded_path
@@ -842,7 +862,7 b' class fncachestore(basicstore):'
 
     def datafiles(
         self, matcher=None, undecodable=None
-    ) -> Generator[StoreEntry, None, None]:
+    ) -> Generator[BaseStoreEntry, None, None]:
         for f in sorted(self.fncache):
             if not _matchtrackedpath(f, matcher):
                 continue
@@ -854,11 +874,9 b' class fncachestore(basicstore):'
                 # However the fncache might contains such file added by
                 # previous version of Mercurial.
                 continue
-            t |= FILEFLAGS_FILELOG
             try:
-                yield StoreEntry(
+                yield RevlogStoreEntry(
                     unencoded_path=f,
-                    is_revlog=True,
                     revlog_type=FILEFLAGS_FILELOG,
                     is_revlog_main=bool(t & FILEFLAGS_REVLOG_MAIN),
                     is_volatile=bool(t & FILEFLAGS_VOLATILE),