test(bench): pick the deltified benchmark objects by chain end and delta status (GO-006)

The size filter excluded every delta of the generated fixture, so the
deltified objects silently fell back to a plain packed blob. Select on the
delta flag and the chainEnd type only, and fail when none qualifies.

commit: eb2657acd9c0c0b172112e3f9a11bd2dbff7d589
author: brice · 11d ago · 2026-10-10 22:15 UTC
parent: b1a375f
signature: GPG VerifiedCD88F9E564E0102646FB6077A1A07C7C7C3E349D · arch-gpg Verified for the committer email

1 file · +10 -11

M bench_test.go +10 -11


@@ -125,8 +125,13 @@ func (fx benchFixture) finish(b testing.B, gitDir string) {
125	125		var id ObjectID
126	126		copy(id[:], p.idx.id(i))
127	127		switch {
128		-	case h.isDelta() && h.size > 200:
129		-	typ, _ := p.chainEnd(off, h)
	128	+	case h.isDelta():
	129	+	// The size of a delta is that of the delta, not of the
	130	+	// object: do not filter on it.
	131	+	typ, err := p.chainEnd(off, h)
	132	+	if err != nil {
	133	+	b.Fatal(err)
	134	+	}
130	135		if typ == TypeBlob && fx.deltaBlob.IsZero() {
131	136		fx.deltaBlob = id
132	137		}

@@ -146,15 +151,9 @@ func (fx benchFixture) finish(b testing.B, gitDir string) {
146	151		if fx.looseBlob.IsZero() {
147	152		fx.looseBlob = fx.packedBlob
148	153		}
149		-	if fx.deltaBlob.IsZero() {
150		-	fx.deltaBlob = fx.packedBlob
151		-	}
152		-	if fx.deltaTree.IsZero() {
153		-	var c Commit
154		-	if err := fx.r.ReadCommit(fx.headCommit, &c); err != nil {
155		-	b.Fatal(err)
156		-	}
157		-	fx.deltaTree = c.Tree
	154	+	if fx.deltaBlob.IsZero() \|\| fx.deltaTree.IsZero() {
	155	+	b.Fatalf("no deltified blob (%v) or tree (%v) in the packs of %s: the deltified benchmarks would measure something else",
	156	+	!fx.deltaBlob.IsZero(), !fx.deltaTree.IsZero(), gitDir)
158	157		}
159	158		if fx.bigTree.IsZero() {
160	159		var c Commit

 			var id ObjectID
 			copy(id[:], p.idx.id(i))
 			switch {
-			case h.isDelta() && h.size > 200:
+			case h.isDelta():
-				typ, _ := p.chainEnd(off, h)
+				// The size of a delta is that of the delta, not of the
+				// object: do not filter on it.
+				typ, err := p.chainEnd(off, h)
+				if err != nil {
+					b.Fatal(err)
+				}
 				if typ == TypeBlob && fx.deltaBlob.IsZero() {
 					fx.deltaBlob = id
 				}
 	if fx.looseBlob.IsZero() {
 		fx.looseBlob = fx.packedBlob
 	}
-	if fx.deltaBlob.IsZero() {
+	if fx.deltaBlob.IsZero() || fx.deltaTree.IsZero() {
-		fx.deltaBlob = fx.packedBlob
+		b.Fatalf("no deltified blob (%v) or tree (%v) in the packs of %s: the deltified benchmarks would measure something else",
-	}
+			!fx.deltaBlob.IsZero(), !fx.deltaTree.IsZero(), gitDir)
-	if fx.deltaTree.IsZero() {
-		var c Commit
-		if err := fx.r.ReadCommit(fx.headCommit, &c); err != nil {
-			b.Fatal(err)
-		}
-		fx.deltaTree = c.Tree
 	}
 	if fx.bigTree.IsZero() {
 		var c Commit