cleanups in revlog.lookup
- add comments
- do a clean separation of the different cases
- don't use a list of each possible node when
doing the lookup, just keep the previous entry
diff -r acd8075edac9 b
--- /dev/null
+++ b/b
@@ -0,0 +1,1 @@
+123
diff -r acd8075edac9 b
--- /dev/null
+++ b/b
@@ -0,0 +1,1 @@
+123
diff -r acd8075edac9 a
--- a/a
+++ b/a
@@ -0,0 +1,1 @@
+foo
diff -r acd8075edac9 b
--- /dev/null
+++ b/b
@@ -0,0 +1,1 @@
+123