.

wcfs/testprog/treegen.py

@@ -181,8 +181,10 @@ def Trees(zstor, r):
         xbtree.Restructure(ztree, tree)
 
         tid = commit("treegen/trees: %s" % treetxt)
-        # XXX print more details
-        print("txn %s -> tree(%s) %s" % (ashex(tid), ashex(ztree._p_oid), treetxt))
+        # XXX print more details?
+        # XXX print just tid (as `zodb commit` does) ?
+        #print("txn %s -> tree(%s) %s" % (ashex(tid), ashex(ztree._p_oid), treetxt))
+        print("%s" % ashex(tid))
 
 
 # AllStructs generates subset of all possible tree changes in

wcfs/δbtail_test.go

@@ -20,9 +20,12 @@
 package main
 
 import (
+	"bufio"
+	"fmt"
 	"io"
 	"os"
 	"os/exec"
+	"strings"
 	"testing"
 
 	"lab.nexedi.com/kirr/go123/xerr"
@@ -37,7 +40,8 @@ type TreeGen struct {
 	zurl	  string
 	pysrv     *exec.Cmd      // spawned `treegen trees`
 	pyin      *io.PipeWriter // input to pysrv
-	pyout     *io.PipeReader // output from pysrv
+	pyoutRaw  *io.PipeReader // output from pysrv
+	pyout     *bufio.Reader  // buffered ^^^
 	treeRoot  zodb.Oid       // oid of the tree treegen works on
 }
 
@@ -48,7 +52,8 @@ func StartTreeGen(zurl string) (_ *TreeGen, err error) {
 	tg := &TreeGen{zurl: zurl}
 	tg.pysrv = exec.Command("./testprog/treegen.py", "trees")
 	tg.pysrv.Stdin, tg.pyin      = io.Pipe()
-	tg.pyout, tg.pysrv.Stdout = io.Pipe()
+	tg.pyoutRaw, tg.pysrv.Stdout = io.Pipe()
+	tg.pyout = bufio.NewReader(tg.pyout)
 	tg.pysrv.Stderr = os.Stderr // no redirection
 
 	err = tg.pysrv.Start()
@@ -66,11 +71,33 @@ func (tg *TreeGen) Close() (err error) {
 	defer xerr.Contextf(&err, "treegen %s: close", tg.zurl)
 
 	err1 := tg.pyin.Close()
-	err2 := tg.pyout.Close()
+	err2 := tg.pyoutRaw.Close()
 	err3 := tg.pysrv.Wait()
 	return xerr.Merge(err1, err2, err3)
 }
 
+// Commit creates new commit with underlying tree changed to tree topology.
+func (tg *TreeGen) Commit(tree string) (_ zodb.Tid, err error) {
+	defer xerr.Contextf(&err, "treegen %s: commit %s", tg.zurl, tree)
+
+	_, err = io.WriteString(tg.pyin, tree + "\n")
+	if err != nil {
+		return zodb.InvalidTid, err
+	}
+
+	reply, err := tg.pyout.ReadString('\n')
+	if err != nil {
+		return zodb.InvalidTid, err
+	}
+	reply = strings.TrimSuffix(reply, "\n")
+
+	tid, err := zodb.ParseTid(reply)
+	if err != nil {
+		return zodb.InvalidTid, fmt.Errorf("invalid reply: %s", err)
+	}
+	return tid, nil
+}
+
 // XXX
 func XXX(t *testing.T, tree1, tree2 string) {
 	// XXX commit tree1