Merge branch 'master' into t

* master: (79 commits)
  go/zodb/zodbtools: Regenerate test data + fix
  go/zodb/fs1: Regenerate
  go/neo/proto: Regenerate
  go/neo/proto: Fix protogen to work without prior `go install`
  go/*: Add Unwrap to custom errors that have Cause
  go/zodb/btree: Represent a tree node - either BTree or Bucket - by Node
  go/zodb: Cosmetics
  go/zodb: LiveCache: Reclassify all objects on cache control change
  go/zodb: LiveCache: Allow objects to be pinned / omitted from the cache
  go/zodb: Prepare to rework/fix LiveCache control
  go/zodb: persistent tests: Factor test database setup out of TestPersistentDB
  go/zodb: persistent test: Fix thinko in tPersistentDB.checkObj
  go/zodb: Don't expose LiveCache internal organization onto its users
  go/zodb: OpenStorage -> Open
  go/zodb: LastTid -> Sync + Head
  go/zodb: DB: preserve δtail not to go down to ø slice on seldom commits
  go/zodb: ΔTail += Data()
  go/zodb/*: Cosmetics, typos, ...
  go/zodb: Connection.Resync
  go/zodb: DB: handle invalidations
  ...

go/neo/proto/protogen.go

-// Copyright (C) 2016-2018  Nexedi SA and Contributors.
+// Copyright (C) 2016-2020  Nexedi SA and Contributors.
 //                          Kirill Smelkov <kirr@nexedi.com>
 //
 // This program is free software: you can Use, Study, Modify and Redistribute
@@ -145,7 +145,11 @@ func (li *localImporter) Import(path string) (*types.Package, error) {
 
 // importer instance - only 1 so that for 2 top-level packages same dependent
 // packages are not reimported several times.
-var localImporterObj = &localImporter{importer.Default()}
+//
+// don't use importer.Default - this importer uses only binaries for installed
+// packages, which might a) get stale wrt sources, or b) be completely missing.
+// https://github.com/golang/go/issues/11415
+var localImporterObj = &localImporter{importer.For("source", nil)}
 
 func loadPkg(pkgPath string, sources ...string) *types.Package {
 	var filev []*ast.File

go/neo/proto/zproto-str.go

@@ -4,6 +4,24 @@ package proto
 
 import "strconv"
 
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[ACK-0]
+	_ = x[NOT_READY-1]
+	_ = x[OID_NOT_FOUND-2]
+	_ = x[TID_NOT_FOUND-3]
+	_ = x[OID_DOES_NOT_EXIST-4]
+	_ = x[PROTOCOL_ERROR-5]
+	_ = x[REPLICATION_ERROR-6]
+	_ = x[CHECKING_ERROR-7]
+	_ = x[BACKEND_NOT_IMPLEMENTED-8]
+	_ = x[NON_READABLE_CELL-9]
+	_ = x[READ_ONLY_ACCESS-10]
+	_ = x[INCOMPLETE_TRANSACTION-11]
+}
+
 const _ErrorCode_name = "ACKNOT_READYOID_NOT_FOUNDTID_NOT_FOUNDOID_DOES_NOT_EXISTPROTOCOL_ERRORREPLICATION_ERRORCHECKING_ERRORBACKEND_NOT_IMPLEMENTEDNON_READABLE_CELLREAD_ONLY_ACCESSINCOMPLETE_TRANSACTION"
 
 var _ErrorCode_index = [...]uint8{0, 3, 12, 25, 38, 56, 70, 87, 101, 124, 141, 157, 179}
@@ -14,6 +32,18 @@ func (i ErrorCode) String() string {
 	}
 	return _ErrorCode_name[_ErrorCode_index[i]:_ErrorCode_index[i+1]]
 }
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[ClusterRecovering-0]
+	_ = x[ClusterVerifying-1]
+	_ = x[ClusterRunning-2]
+	_ = x[ClusterStopping-3]
+	_ = x[STARTING_BACKUP-4]
+	_ = x[BACKINGUP-5]
+	_ = x[STOPPING_BACKUP-6]
+}
 
 const _ClusterState_name = "ClusterRecoveringClusterVerifyingClusterRunningClusterStoppingSTARTING_BACKUPBACKINGUPSTOPPING_BACKUP"
 
@@ -25,6 +55,15 @@ func (i ClusterState) String() string {
 	}
 	return _ClusterState_name[_ClusterState_index[i]:_ClusterState_index[i+1]]
 }
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[MASTER-0]
+	_ = x[STORAGE-1]
+	_ = x[CLIENT-2]
+	_ = x[ADMIN-3]
+}
 
 const _NodeType_name = "MASTERSTORAGECLIENTADMIN"
 
@@ -36,6 +75,15 @@ func (i NodeType) String() string {
 	}
 	return _NodeType_name[_NodeType_index[i]:_NodeType_index[i+1]]
 }
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[UNKNOWN-0]
+	_ = x[DOWN-1]
+	_ = x[RUNNING-2]
+	_ = x[PENDING-3]
+}
 
 const _NodeState_name = "UNKNOWNDOWNRUNNINGPENDING"
 
@@ -47,6 +95,16 @@ func (i NodeState) String() string {
 	}
 	return _NodeState_name[_NodeState_index[i]:_NodeState_index[i+1]]
 }
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[UP_TO_DATE-0]
+	_ = x[OUT_OF_DATE-1]
+	_ = x[FEEDING-2]
+	_ = x[DISCARDED-3]
+	_ = x[CORRUPTED-4]
+}
 
 const _CellState_name = "UP_TO_DATEOUT_OF_DATEFEEDINGDISCARDEDCORRUPTED"
 

go/zodb/storage/fs1/fsb/fsbtree.go

-// Code generated by gen-fsbtree from github.com/cznic/b 93348d0; DO NOT EDIT.
+// Code generated by gen-fsbtree from github.com/cznic/b 8c9698d; DO NOT EDIT.
 // (from patched version available at https://lab.nexedi.com/kirr/b.git)
 //
 // KEY=zodb.Oid  VALUE=int64

go/zodb/storage/fs1/fsb/fsbtree_util.go

-// Code generated by gen-fsbtree from github.com/cznic/b 93348d0; DO NOT EDIT.
+// Code generated by gen-fsbtree from github.com/cznic/b 8c9698d; DO NOT EDIT.
 // (from patched version available at https://lab.nexedi.com/kirr/b.git)
 //
 // ---- 8< ----

go/zodb/zodbtools/dump.go

-// Copyright (C) 2016-2019  Nexedi SA and Contributors.
+// Copyright (C) 2016-2020  Nexedi SA and Contributors.
 //                          Kirill Smelkov <kirr@nexedi.com>
 //
 // This program is free software: you can Use, Study, Modify and Redistribute
@@ -72,8 +72,6 @@ type dumper struct {
 	W          io.Writer
 	HashOnly   bool		// whether to dump only hashes of data without content
 
-	afterFirst bool // true after first transaction has been dumped
-
 	buf xfmt.Buffer // reusable data buffer for formatting
 }
 
@@ -152,15 +150,8 @@ func (d *dumper) DumpTxn(ctx context.Context, txni *zodb.TxnInfo, dataIter zodb.
 
 	var datai *zodb.DataInfo
 
-	// LF in-between txn records
-	vskip := "\n"
-	if !d.afterFirst {
-		vskip = ""
-		d.afterFirst = true
-	}
-
-	_, err = fmt.Fprintf(d.W, "%stxn %s %q\nuser %q\ndescription %q\nextension %q\n",
-			vskip, txni.Tid, string(txni.Status), txni.User, txni.Description, txni.Extension)
+	_, err = fmt.Fprintf(d.W, "txn %s %q\nuser %q\ndescription %q\nextension %q\n",
+			txni.Tid, string(txni.Status), txni.User, txni.Description, txni.Extension)
 	if err != nil {
 		return err
 	}
@@ -170,18 +161,19 @@ func (d *dumper) DumpTxn(ctx context.Context, txni *zodb.TxnInfo, dataIter zodb.
 		datai, err = dataIter.NextData(ctx)
 		if err != nil {
 			if err == io.EOF {
-				err = nil	// XXX -> okEOF ?
+				break
 			}
 
-			break
+			return err
 		}
 
 		err = d.DumpData(datai)
 		if err != nil {
-			break
+			return err
 		}
 	}
 
+	_, err = d.W.Write(_LF)
 	return err
 }