Merge branch 'pks-gitaly-gitconfig-clean' into pks-ci-fail-on-gitconfig-readspks-ci-fail-on-gitconfig-reads

17 files changed, 347 insertions, 331 deletions

diff --git a/cmd/gitaly-git2go-v15/cherry_pick_test.go b/cmd/gitaly-git2go-v15/cherry_pick_test.go
index 5902d1fdf..4e4478317 100644
--- a/cmd/gitaly-git2go-v15/cherry_pick_test.go
+++ b/cmd/gitaly-git2go-v15/cherry_pick_test.go
@@ -12,7 +12,7 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"gitlab.com/gitlab-org/gitaly/v15/cmd/gitaly-git2go-v15/git2goutil"
-	cmdtesthelper "gitlab.com/gitlab-org/gitaly/v15/cmd/gitaly-git2go-v15/testhelper"
+	"gitlab.com/gitlab-org/gitaly/v15/internal/git/gittest"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/git2go"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/testhelper"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/testhelper/testcfg"
@@ -81,9 +81,9 @@ func TestCherryPick_validation(t *testing.T) {
 func TestCherryPick(t *testing.T) {
 	testcases := []struct {
 		desc             string
-		base             map[string]string
-		ours             map[string]string
-		commit           map[string]string
+		base             []gittest.TreeEntry
+		ours             []gittest.TreeEntry
+		commit           []gittest.TreeEntry
 		expected         map[string]string
 		expectedCommitID string
 		expectedErr      error
@@ -91,44 +91,44 @@ func TestCherryPick(t *testing.T) {
 	}{
 		{
 			desc: "trivial cherry-pick succeeds",
-			base: map[string]string{
-				"file": "foo",
+			base: []gittest.TreeEntry{
+				{Path: "file", Content: "foo", Mode: "100644"},
 			},
-			ours: map[string]string{
-				"file": "foo",
+			ours: []gittest.TreeEntry{
+				{Path: "file", Content: "foo", Mode: "100644"},
 			},
-			commit: map[string]string{
-				"file": "foobar",
+			commit: []gittest.TreeEntry{
+				{Path: "file", Content: "foobar", Mode: "100644"},
 			},
 			expected: map[string]string{
 				"file": "foobar",
 			},
-			expectedCommitID: "aa3c9f5ad67ad86e313129a851f6d64614be7f6e",
+			expectedCommitID: "a54ea83118c363c34cc605a6e61fd7abc4795cc4",
 		},
 		{
 			desc: "conflicting cherry-pick fails",
-			base: map[string]string{
-				"file": "foo",
+			base: []gittest.TreeEntry{
+				{Path: "file", Content: "foo", Mode: "100644"},
 			},
-			ours: map[string]string{
-				"file": "fooqux",
+			ours: []gittest.TreeEntry{
+				{Path: "file", Content: "fooqux", Mode: "100644"},
 			},
-			commit: map[string]string{
-				"file": "foobar",
+			commit: []gittest.TreeEntry{
+				{Path: "file", Content: "foobar", Mode: "100644"},
 			},
 			expectedErr:    git2go.HasConflictsError{},
 			expectedErrMsg: "cherry-pick: could not apply due to conflicts",
 		},
 		{
 			desc: "empty cherry-pick fails",
-			base: map[string]string{
-				"file": "foo",
+			base: []gittest.TreeEntry{
+				{Path: "file", Content: "foo", Mode: "100644"},
 			},
-			ours: map[string]string{
-				"file": "fooqux",
+			ours: []gittest.TreeEntry{
+				{Path: "file", Content: "fooqux", Mode: "100644"},
 			},
-			commit: map[string]string{
-				"file": "fooqux",
+			commit: []gittest.TreeEntry{
+				{Path: "file", Content: "fooqux", Mode: "100644"},
 			},
 			expectedErr:    git2go.EmptyError{},
 			expectedErrMsg: "cherry-pick: could not apply because the result was empty",
@@ -139,8 +139,8 @@ func TestCherryPick(t *testing.T) {
 		},
 		{
 			desc: "fails on nonexistent cherry-pick commit",
-			ours: map[string]string{
-				"file": "fooqux",
+			ours: []gittest.TreeEntry{
+				{Path: "file", Content: "fooqux", Mode: "100644"},
 			},
 			expectedErrMsg: "cherry-pick: commit lookup: lookup commit \"nonexistent\": revspec 'nonexistent' not found",
 		},
@@ -150,14 +150,14 @@ func TestCherryPick(t *testing.T) {
 		testcfg.BuildGitalyGit2Go(t, cfg)
 		executor := buildExecutor(t, cfg)
 
-		base := cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{nil}, tc.base)
+		base := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(), gittest.WithTreeEntries(tc.base...))
 
 		ours, commit := "nonexistent", "nonexistent"
 		if len(tc.ours) > 0 {
-			ours = cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{base}, tc.ours).String()
+			ours = gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(base), gittest.WithTreeEntries(tc.ours...)).String()
 		}
 		if len(tc.commit) > 0 {
-			commit = cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{base}, tc.commit).String()
+			commit = gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(base), gittest.WithTreeEntries(tc.commit...)).String()
 		}
 
 		t.Run(tc.desc, func(t *testing.T) {
@@ -200,7 +200,7 @@ func TestCherryPick(t *testing.T) {
 
 			commit, err := repo.LookupCommit(commitOid)
 			require.NoError(t, err)
-			require.Equal(t, &cmdtesthelper.DefaultAuthor, commit.Author())
+			require.Equal(t, &DefaultAuthor, commit.Author())
 			require.Equal(t, &committer, commit.Committer())
 
 			tree, err := commit.Tree()
diff --git a/cmd/gitaly-git2go-v15/conflicts_test.go b/cmd/gitaly-git2go-v15/conflicts_test.go
index 6fa843aa6..4551ceb7c 100644
--- a/cmd/gitaly-git2go-v15/conflicts_test.go
+++ b/cmd/gitaly-git2go-v15/conflicts_test.go
@@ -7,10 +7,9 @@ import (
 	"fmt"
 	"testing"
 
-	git "github.com/libgit2/git2go/v33"
 	"github.com/stretchr/testify/require"
-	cmdtesthelper "gitlab.com/gitlab-org/gitaly/v15/cmd/gitaly-git2go-v15/testhelper"
 	glgit "gitlab.com/gitlab-org/gitaly/v15/internal/git"
+	"gitlab.com/gitlab-org/gitaly/v15/internal/git/gittest"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/git2go"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/testhelper"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/testhelper/testcfg"
@@ -21,34 +20,34 @@ import (
 func TestConflicts(t *testing.T) {
 	testcases := []struct {
 		desc      string
-		base      map[string]string
-		ours      map[string]string
-		theirs    map[string]string
+		base      []gittest.TreeEntry
+		ours      []gittest.TreeEntry
+		theirs    []gittest.TreeEntry
 		conflicts []git2go.Conflict
 	}{
 		{
 			desc: "no conflicts",
-			base: map[string]string{
-				"file": "a",
+			base: []gittest.TreeEntry{
+				{Path: "file", Content: "a", Mode: "100644"},
 			},
-			ours: map[string]string{
-				"file": "a",
+			ours: []gittest.TreeEntry{
+				{Path: "file", Content: "a", Mode: "100644"},
 			},
-			theirs: map[string]string{
-				"file": "b",
+			theirs: []gittest.TreeEntry{
+				{Path: "file", Content: "b", Mode: "100644"},
 			},
 			conflicts: nil,
 		},
 		{
 			desc: "single file",
-			base: map[string]string{
-				"file": "a",
+			base: []gittest.TreeEntry{
+				{Path: "file", Content: "a", Mode: "100644"},
 			},
-			ours: map[string]string{
-				"file": "b",
+			ours: []gittest.TreeEntry{
+				{Path: "file", Content: "b", Mode: "100644"},
 			},
-			theirs: map[string]string{
-				"file": "c",
+			theirs: []gittest.TreeEntry{
+				{Path: "file", Content: "c", Mode: "100644"},
 			},
 			conflicts: []git2go.Conflict{
 				{
@@ -61,17 +60,17 @@ func TestConflicts(t *testing.T) {
 		},
 		{
 			desc: "multiple files with single conflict",
-			base: map[string]string{
-				"file-1": "a",
-				"file-2": "a",
+			base: []gittest.TreeEntry{
+				{Path: "file-1", Content: "a", Mode: "100644"},
+				{Path: "file-2", Content: "a", Mode: "100644"},
 			},
-			ours: map[string]string{
-				"file-1": "b",
-				"file-2": "b",
+			ours: []gittest.TreeEntry{
+				{Path: "file-1", Content: "b", Mode: "100644"},
+				{Path: "file-2", Content: "b", Mode: "100644"},
 			},
-			theirs: map[string]string{
-				"file-1": "a",
-				"file-2": "c",
+			theirs: []gittest.TreeEntry{
+				{Path: "file-1", Content: "a", Mode: "100644"},
+				{Path: "file-2", Content: "c", Mode: "100644"},
 			},
 			conflicts: []git2go.Conflict{
 				{
@@ -84,17 +83,17 @@ func TestConflicts(t *testing.T) {
 		},
 		{
 			desc: "multiple conflicts",
-			base: map[string]string{
-				"file-1": "a",
-				"file-2": "a",
+			base: []gittest.TreeEntry{
+				{Path: "file-1", Content: "a", Mode: "100644"},
+				{Path: "file-2", Content: "a", Mode: "100644"},
 			},
-			ours: map[string]string{
-				"file-1": "b",
-				"file-2": "b",
+			ours: []gittest.TreeEntry{
+				{Path: "file-1", Content: "b", Mode: "100644"},
+				{Path: "file-2", Content: "b", Mode: "100644"},
 			},
-			theirs: map[string]string{
-				"file-1": "c",
-				"file-2": "c",
+			theirs: []gittest.TreeEntry{
+				{Path: "file-1", Content: "c", Mode: "100644"},
+				{Path: "file-2", Content: "c", Mode: "100644"},
 			},
 			conflicts: []git2go.Conflict{
 				{
@@ -113,14 +112,14 @@ func TestConflicts(t *testing.T) {
 		},
 		{
 			desc: "modified-delete-conflict",
-			base: map[string]string{
-				"file": "content",
+			base: []gittest.TreeEntry{
+				{Path: "file", Content: "content", Mode: "100644"},
 			},
-			ours: map[string]string{
-				"file": "changed",
+			ours: []gittest.TreeEntry{
+				{Path: "file", Content: "changed", Mode: "100644"},
 			},
-			theirs: map[string]string{
-				"different-file": "unrelated",
+			theirs: []gittest.TreeEntry{
+				{Path: "different-file", Content: "unrelated", Mode: "100644"},
 			},
 			conflicts: []git2go.Conflict{
 				{
@@ -136,14 +135,14 @@ func TestConflicts(t *testing.T) {
 			// detection and so don't we. The rename conflict is
 			// thus split up into three conflicts.
 			desc: "rename-rename-conflict",
-			base: map[string]string{
-				"file": "a\nb\nc\nd\ne\nf\ng\n",
+			base: []gittest.TreeEntry{
+				{Path: "file", Content: "a\nb\nc\nd\ne\nf\ng\n", Mode: "100644"},
 			},
-			ours: map[string]string{
-				"renamed-1": "a\nb\nc\nd\ne\nf\ng\n",
+			ours: []gittest.TreeEntry{
+				{Path: "renamed-1", Content: "a\nb\nc\nd\ne\nf\ng\n", Mode: "100644"},
 			},
-			theirs: map[string]string{
-				"renamed-2": "a\nb\nc\nd\ne\nf\ng\n",
+			theirs: []gittest.TreeEntry{
+				{Path: "renamed-2", Content: "a\nb\nc\nd\ne\nf\ng\n", Mode: "100644"},
 			},
 			conflicts: []git2go.Conflict{
 				{
@@ -174,9 +173,9 @@ func TestConflicts(t *testing.T) {
 
 		testcfg.BuildGitalyGit2Go(t, cfg)
 
-		base := cmdtesthelper.BuildCommit(t, repoPath, nil, tc.base)
-		ours := cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{base}, tc.ours)
-		theirs := cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{base}, tc.theirs)
+		base := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(), gittest.WithTreeEntries(tc.base...))
+		ours := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(base), gittest.WithTreeEntries(tc.ours...))
+		theirs := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(base), gittest.WithTreeEntries(tc.theirs...))
 
 		t.Run(tc.desc, func(t *testing.T) {
 			ctx := testhelper.Context(t)
@@ -195,7 +194,7 @@ func TestConflicts(t *testing.T) {
 
 func TestConflicts_checkError(t *testing.T) {
 	cfg, repo, repoPath := testcfg.BuildWithRepo(t)
-	base := cmdtesthelper.BuildCommit(t, repoPath, nil, nil)
+	base := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(), gittest.WithTreeEntries())
 	validOID := glgit.ObjectID(base.String())
 	executor := buildExecutor(t, cfg)
 
diff --git a/cmd/gitaly-git2go-v15/main.go b/cmd/gitaly-git2go-v15/main.go
index dc3516af2..e4a51354e 100644
--- a/cmd/gitaly-git2go-v15/main.go
+++ b/cmd/gitaly-git2go-v15/main.go
@@ -102,6 +102,16 @@ func main() {
 		fatalf(logger, encoder, "enable fsync: %s", err)
 	}
 
+	for _, configLevel := range []git.ConfigLevel{
+		git.ConfigLevelSystem,
+		git.ConfigLevelXDG,
+		git.ConfigLevelGlobal,
+	} {
+		if err := git.SetSearchPath(configLevel, "/dev/null"); err != nil {
+			fatalf(logger, encoder, "setting search path: %s", err)
+		}
+	}
+
 	subcmdLogger := logger.WithField("command.subcommand", subcmdFlags.Name())
 	subcmdLogger.Infof("starting %s command", subcmdFlags.Name())
 
diff --git a/cmd/gitaly-git2go-v15/merge_test.go b/cmd/gitaly-git2go-v15/merge_test.go
index 68d36b9f7..8f1b79968 100644
--- a/cmd/gitaly-git2go-v15/merge_test.go
+++ b/cmd/gitaly-git2go-v15/merge_test.go
@@ -8,11 +8,11 @@ import (
 	"testing"
 	"time"
 
-	git "github.com/libgit2/git2go/v33"
+	libgit2 "github.com/libgit2/git2go/v33"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"gitlab.com/gitlab-org/gitaly/v15/cmd/gitaly-git2go-v15/git2goutil"
-	cmdtesthelper "gitlab.com/gitlab-org/gitaly/v15/cmd/gitaly-git2go-v15/testhelper"
+	"gitlab.com/gitlab-org/gitaly/v15/internal/git"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/git/gittest"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/git2go"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/testhelper"
@@ -113,9 +113,9 @@ func TestMerge_trees(t *testing.T) {
 
 	testcases := []struct {
 		desc             string
-		base             map[string]string
-		ours             map[string]string
-		theirs           map[string]string
+		base             []gittest.TreeEntry
+		ours             []gittest.TreeEntry
+		theirs           []gittest.TreeEntry
 		expected         map[string]string
 		withCommitter    bool
 		squash           bool
@@ -124,113 +124,113 @@ func TestMerge_trees(t *testing.T) {
 	}{
 		{
 			desc: "trivial merge succeeds",
-			base: map[string]string{
-				"file": "a",
+			base: []gittest.TreeEntry{
+				{Path: "file", Content: "a", Mode: "100644"},
 			},
-			ours: map[string]string{
-				"file": "a",
+			ours: []gittest.TreeEntry{
+				{Path: "file", Content: "a", Mode: "100644"},
 			},
-			theirs: map[string]string{
-				"file": "a",
+			theirs: []gittest.TreeEntry{
+				{Path: "file", Content: "a", Mode: "100644"},
 			},
 			expected: map[string]string{
 				"file": "a",
 			},
 			expectedResponse: git2go.MergeResult{
-				CommitID: "7d5ae8fb6d2b301c53560bd728004d77778998df",
+				CommitID: "0db317551c49eddadde2b337550d8e57d9536886",
 			},
 		},
 		{
 			desc: "trivial merge with different committer succeeds",
-			base: map[string]string{
-				"file": "a",
+			base: []gittest.TreeEntry{
+				{Path: "file", Content: "a", Mode: "100644"},
 			},
-			ours: map[string]string{
-				"file": "a",
+			ours: []gittest.TreeEntry{
+				{Path: "file", Content: "a", Mode: "100644"},
 			},
-			theirs: map[string]string{
-				"file": "a",
+			theirs: []gittest.TreeEntry{
+				{Path: "file", Content: "a", Mode: "100644"},
 			},
 			expected: map[string]string{
 				"file": "a",
 			},
 			withCommitter: true,
 			expectedResponse: git2go.MergeResult{
-				CommitID: "cba8c5ddf5a5a24f2f606e4b62d348feb1214b70",
+				CommitID: "38dcbe72d91ed5621286290f70df9a5dd08f5cb6",
 			},
 		},
 		{
 			desc: "trivial squash succeeds",
-			base: map[string]string{
-				"file": "a",
+			base: []gittest.TreeEntry{
+				{Path: "file", Content: "a", Mode: "100644"},
 			},
-			ours: map[string]string{
-				"file": "a",
+			ours: []gittest.TreeEntry{
+				{Path: "file", Content: "a", Mode: "100644"},
 			},
-			theirs: map[string]string{
-				"file": "a",
+			theirs: []gittest.TreeEntry{
+				{Path: "file", Content: "a", Mode: "100644"},
 			},
 			expected: map[string]string{
 				"file": "a",
 			},
 			squash: true,
 			expectedResponse: git2go.MergeResult{
-				CommitID: "d4c52f063cd6544959d6b0d9a3d8fa8463c34086",
+				CommitID: "a0781480ce3cbba80440e6c112c5ee7f718ed3c2",
 			},
 		},
 		{
 			desc: "non-trivial merge succeeds",
-			base: map[string]string{
-				"file": "a\nb\nc\nd\ne\nf\n",
+			base: []gittest.TreeEntry{
+				{Path: "file", Content: "a\nb\nc\nd\ne\nf\n", Mode: "100644"},
 			},
-			ours: map[string]string{
-				"file": "0\na\nb\nc\nd\ne\nf\n",
+			ours: []gittest.TreeEntry{
+				{Path: "file", Content: "0\na\nb\nc\nd\ne\nf\n", Mode: "100644"},
 			},
-			theirs: map[string]string{
-				"file": "a\nb\nc\nd\ne\nf\n0\n",
+			theirs: []gittest.TreeEntry{
+				{Path: "file", Content: "a\nb\nc\nd\ne\nf\n0\n", Mode: "100644"},
 			},
 			expected: map[string]string{
 				"file": "0\na\nb\nc\nd\ne\nf\n0\n",
 			},
 			expectedResponse: git2go.MergeResult{
-				CommitID: "348b9b489c3ca128a4555c7a51b20335262519c7",
+				CommitID: "3c030d1ee80bbb005666619375fa0629c86b9534",
 			},
 		},
 		{
 			desc: "non-trivial squash succeeds",
-			base: map[string]string{
-				"file": "a\nb\nc\nd\ne\nf\n",
+			base: []gittest.TreeEntry{
+				{Path: "file", Content: "a\nb\nc\nd\ne\nf\n", Mode: "100644"},
 			},
-			ours: map[string]string{
-				"file": "0\na\nb\nc\nd\ne\nf\n",
+			ours: []gittest.TreeEntry{
+				{Path: "file", Content: "0\na\nb\nc\nd\ne\nf\n", Mode: "100644"},
 			},
-			theirs: map[string]string{
-				"file": "a\nb\nc\nd\ne\nf\n0\n",
+			theirs: []gittest.TreeEntry{
+				{Path: "file", Content: "a\nb\nc\nd\ne\nf\n0\n", Mode: "100644"},
 			},
 			expected: map[string]string{
 				"file": "0\na\nb\nc\nd\ne\nf\n0\n",
 			},
 			squash: true,
 			expectedResponse: git2go.MergeResult{
-				CommitID: "7ef7460f69503265a247e06218391cfa57c521fc",
+				CommitID: "43853c4a027a67c7e39afa8e7ef0a34a1874ef26",
 			},
 		},
 		{
 			desc: "multiple files succeed",
-			base: map[string]string{
-				"1": "foo",
-				"2": "bar",
-				"3": "qux",
+			base: []gittest.TreeEntry{
+				{Path: "1", Content: "foo", Mode: "100644"},
+				{Path: "2", Content: "bar", Mode: "100644"},
+				{Path: "3", Content: "qux", Mode: "100644"},
 			},
-			ours: map[string]string{
-				"1": "foo",
-				"2": "modified",
-				"3": "qux",
+			ours: []gittest.TreeEntry{
+				{Path: "1", Content: "foo", Mode: "100644"},
+				{Path: "2", Content: "modified", Mode: "100644"},
+				{Path: "3", Content: "qux", Mode: "100644"},
 			},
-			theirs: map[string]string{
-				"1": "modified",
-				"2": "bar",
-				"3": "qux",
+			theirs: []gittest.TreeEntry{
+				{Path: "1", Content: "modified", Mode: "100644"},
+				{Path: "2", Content: "bar", Mode: "100644"},
+				{Path: "3", Content: "qux", Mode: "100644"},
 			},
 			expected: map[string]string{
 				"1": "modified",
@@ -238,25 +238,25 @@ func TestMerge_trees(t *testing.T) {
 				"3": "qux",
 			},
 			expectedResponse: git2go.MergeResult{
-				CommitID: "e9be4578f89ea52d44936fb36517e837d698b34b",
+				CommitID: "6be1fdb2c4116881c7a82575be41618e8a690ff4",
 			},
 		},
 		{
 			desc: "multiple files squash succeed",
-			base: map[string]string{
-				"1": "foo",
-				"2": "bar",
-				"3": "qux",
+			base: []gittest.TreeEntry{
+				{Path: "1", Content: "foo", Mode: "100644"},
+				{Path: "2", Content: "bar", Mode: "100644"},
+				{Path: "3", Content: "qux", Mode: "100644"},
 			},
-			ours: map[string]string{
-				"1": "foo",
-				"2": "modified",
-				"3": "qux",
+			ours: []gittest.TreeEntry{
+				{Path: "1", Content: "foo", Mode: "100644"},
+				{Path: "2", Content: "modified", Mode: "100644"},
+				{Path: "3", Content: "qux", Mode: "100644"},
 			},
-			theirs: map[string]string{
-				"1": "modified",
-				"2": "bar",
-				"3": "qux",
+			theirs: []gittest.TreeEntry{
+				{Path: "1", Content: "modified", Mode: "100644"},
+				{Path: "2", Content: "bar", Mode: "100644"},
+				{Path: "3", Content: "qux", Mode: "100644"},
 			},
 			expected: map[string]string{
 				"1": "modified",
@@ -265,19 +265,19 @@ func TestMerge_trees(t *testing.T) {
 			},
 			squash: true,
 			expectedResponse: git2go.MergeResult{
-				CommitID: "a680459fe541be728c8494fb76c233a344c04460",
+				CommitID: "fe094a98b22ac53e1da1a9eb16118ce49f01fdbe",
 			},
 		},
 		{
 			desc: "conflicting merge fails",
-			base: map[string]string{
-				"1": "foo",
+			base: []gittest.TreeEntry{
+				{Path: "1", Content: "foo", Mode: "100644"},
 			},
-			ours: map[string]string{
-				"1": "bar",
+			ours: []gittest.TreeEntry{
+				{Path: "1", Content: "bar", Mode: "100644"},
 			},
-			theirs: map[string]string{
-				"1": "qux",
+			theirs: []gittest.TreeEntry{
+				{Path: "1", Content: "qux", Mode: "100644"},
 			},
 			expectedErr: fmt.Errorf("merge: %w", git2go.ConflictingFilesError{
 				ConflictingFiles: []string{"1"},
@@ -290,9 +290,9 @@ func TestMerge_trees(t *testing.T) {
 		testcfg.BuildGitalyGit2Go(t, cfg)
 		executor := buildExecutor(t, cfg)
 
-		base := cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{nil}, tc.base)
-		ours := cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{base}, tc.ours)
-		theirs := cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{base}, tc.theirs)
+		base := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(), gittest.WithTreeEntries(tc.base...))
+		ours := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(base), gittest.WithTreeEntries(tc.ours...))
+		theirs := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(base), gittest.WithTreeEntries(tc.theirs...))
 
 		authorDate := time.Date(2020, 7, 30, 7, 45, 50, 0, time.FixedZone("UTC+2", +2*60*60))
 		committerDate := time.Date(2021, 7, 30, 7, 45, 50, 0, time.FixedZone("UTC+2", +2*60*60))
@@ -327,7 +327,7 @@ func TestMerge_trees(t *testing.T) {
 			require.NoError(t, err)
 			defer repo.Free()
 
-			commitOid, err := git.NewOid(response.CommitID)
+			commitOid, err := libgit2.NewOid(response.CommitID)
 			require.NoError(t, err)
 
 			commit, err := repo.LookupCommit(commitOid)
@@ -358,15 +358,15 @@ func TestMerge_squash(t *testing.T) {
 	testcfg.BuildGitalyGit2Go(t, cfg)
 	executor := buildExecutor(t, cfg)
 
-	baseFiles := map[string]string{"file.txt": "b\nc"}
-	ourFiles := map[string]string{"file.txt": "a\nb\nc"}
-	theirFiles1 := map[string]string{"file.txt": "b\nc\nd"}
-	theirFiles2 := map[string]string{"file.txt": "b\nc\nd\ne"}
+	baseFile := gittest.TreeEntry{Path: "file.txt", Content: "b\nc", Mode: "100644"}
+	ourFile := gittest.TreeEntry{Path: "file.txt", Content: "a\nb\nc", Mode: "100644"}
+	theirFile1 := gittest.TreeEntry{Path: "file.txt", Content: "b\nc\nd", Mode: "100644"}
+	theirFile2 := gittest.TreeEntry{Path: "file.txt", Content: "b\nc\nd\ne", Mode: "100644"}
 
-	base := cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{nil}, baseFiles)
-	ours := cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{base}, ourFiles)
-	theirs1 := cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{base}, theirFiles1)
-	theirs2 := cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{theirs1}, theirFiles2)
+	base := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(), gittest.WithTreeEntries(baseFile))
+	ours := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(base), gittest.WithTreeEntries(ourFile))
+	theirs1 := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(base), gittest.WithTreeEntries(theirFile1))
+	theirs2 := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(theirs1), gittest.WithTreeEntries(theirFile2))
 
 	date := time.Date(2020, 7, 30, 7, 45, 50, 0, time.FixedZone("UTC+2", +2*60*60))
 	response, err := executor.Merge(ctx, repoProto, git2go.MergeCommand{
@@ -380,15 +380,17 @@ func TestMerge_squash(t *testing.T) {
 		Squash:     true,
 	})
 	require.NoError(t, err)
-	assert.Equal(t, "027d909803fbb3d17c3b10c1dfe8f120d99392e4", response.CommitID)
+	assert.Equal(t, "882b43b68d160876e3833dc6bbabf7032058e837", response.CommitID)
 
 	repo, err := git2goutil.OpenRepository(repoPath)
 	require.NoError(t, err)
 
-	commitOid, err := git.NewOid(response.CommitID)
+	commitOid, err := libgit2.NewOid(response.CommitID)
 	require.NoError(t, err)
 
-	isDescendant, err := repo.DescendantOf(commitOid, theirs2)
+	theirs2Oid, err := libgit2.NewOid(theirs2.String())
+	require.NoError(t, err)
+	isDescendant, err := repo.DescendantOf(commitOid, theirs2Oid)
 	require.NoError(t, err)
 	require.False(t, isDescendant)
 
@@ -396,7 +398,7 @@ func TestMerge_squash(t *testing.T) {
 	require.NoError(t, err)
 
 	require.Equal(t, uint(1), commit.ParentCount())
-	require.Equal(t, ours, commit.ParentId(0))
+	require.Equal(t, ours.String(), commit.ParentId(0).String())
 
 	tree, err := commit.Tree()
 	require.NoError(t, err)
@@ -419,15 +421,21 @@ func TestMerge_recursive(t *testing.T) {
 
 	repoProto, repoPath := gittest.InitRepo(t, cfg, cfg.Storages[0])
 
-	base := cmdtesthelper.BuildCommit(t, repoPath, nil, map[string]string{"base": "base\n"})
+	base := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(), gittest.WithTreeEntries(
+		gittest.TreeEntry{Path: "base", Content: "base\n", Mode: "100644"},
+	))
 
-	oursContents := map[string]string{"base": "base\n", "ours": "ours-0\n"}
-	ours := make([]*git.Oid, git2go.MergeRecursionLimit)
-	ours[0] = cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{base}, oursContents)
+	ours := make([]git.ObjectID, git2go.MergeRecursionLimit)
+	ours[0] = gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(base), gittest.WithTreeEntries(
+		gittest.TreeEntry{Path: "base", Content: "base\n", Mode: "100644"},
+		gittest.TreeEntry{Path: "ours", Content: "ours-0\n", Mode: "100644"},
+	))
 
-	theirsContents := map[string]string{"base": "base\n", "theirs": "theirs-0\n"}
-	theirs := make([]*git.Oid, git2go.MergeRecursionLimit)
-	theirs[0] = cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{base}, theirsContents)
+	theirs := make([]git.ObjectID, git2go.MergeRecursionLimit)
+	theirs[0] = gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(base), gittest.WithTreeEntries(
+		gittest.TreeEntry{Path: "base", Content: "base\n", Mode: "100644"},
+		gittest.TreeEntry{Path: "theirs", Content: "theirs-0\n", Mode: "100644"},
+	))
 
 	// We're now creating a set of criss-cross merges which look like the following graph:
 	//
@@ -441,13 +449,17 @@ func TestMerge_recursive(t *testing.T) {
 	// is not unique, and as a result the merge will generate virtual merge bases for each of
 	// the criss-cross merges. This operation may thus be heavily expensive to perform.
 	for i := 1; i < git2go.MergeRecursionLimit; i++ {
-		oursContents["ours"] = fmt.Sprintf("ours-%d\n", i)
-		oursContents["theirs"] = fmt.Sprintf("theirs-%d\n", i-1)
-		theirsContents["ours"] = fmt.Sprintf("ours-%d\n", i-1)
-		theirsContents["theirs"] = fmt.Sprintf("theirs-%d\n", i)
-
-		ours[i] = cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{ours[i-1], theirs[i-1]}, oursContents)
-		theirs[i] = cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{theirs[i-1], ours[i-1]}, theirsContents)
+		ours[i] = gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(ours[i-1], theirs[i-1]), gittest.WithTreeEntries(
+			gittest.TreeEntry{Path: "base", Content: "base\n", Mode: "100644"},
+			gittest.TreeEntry{Path: "ours", Content: fmt.Sprintf("ours-%d\n", i), Mode: "100644"},
+			gittest.TreeEntry{Path: "theirs", Content: fmt.Sprintf("theirs-%d\n", i-1), Mode: "100644"},
+		))
+
+		theirs[i] = gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(theirs[i-1], ours[i-1]), gittest.WithTreeEntries(
+			gittest.TreeEntry{Path: "base", Content: "base\n", Mode: "100644"},
+			gittest.TreeEntry{Path: "ours", Content: fmt.Sprintf("ours-%d\n", i-1), Mode: "100644"},
+			gittest.TreeEntry{Path: "theirs", Content: fmt.Sprintf("theirs-%d\n", i), Mode: "100644"},
+		))
 	}
 
 	authorDate := time.Date(2020, 7, 30, 7, 45, 50, 0, time.FixedZone("UTC+2", +2*60*60))
@@ -500,7 +512,7 @@ func TestMerge_recursive(t *testing.T) {
 	repo, err := git2goutil.OpenRepository(repoPath)
 	require.NoError(t, err)
 
-	commitOid, err := git.NewOid(response.CommitID)
+	commitOid, err := libgit2.NewOid(response.CommitID)
 	require.NoError(t, err)
 
 	commit, err := repo.LookupCommit(commitOid)
diff --git a/cmd/gitaly-git2go-v15/rebase_test.go b/cmd/gitaly-git2go-v15/rebase_test.go
index a596876f6..a7df2a912 100644
--- a/cmd/gitaly-git2go-v15/rebase_test.go
+++ b/cmd/gitaly-git2go-v15/rebase_test.go
@@ -11,7 +11,6 @@ import (
 	git "github.com/libgit2/git2go/v33"
 	"github.com/stretchr/testify/require"
 	"gitlab.com/gitlab-org/gitaly/v15/cmd/gitaly-git2go-v15/git2goutil"
-	cmdtesthelper "gitlab.com/gitlab-org/gitaly/v15/cmd/gitaly-git2go-v15/testhelper"
 	gitalygit "gitlab.com/gitlab-org/gitaly/v15/internal/git"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/git/gittest"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/git2go"
@@ -125,12 +124,12 @@ func TestRebase_rebase(t *testing.T) {
 				require.NoError(t, err)
 				tree, err := other.Tree()
 				require.NoError(t, err)
-				newOid, err := repo.CreateCommitFromIds("refs/heads/branch-merged-plus-one", &cmdtesthelper.DefaultAuthor, &cmdtesthelper.DefaultAuthor, "Message", tree.Object.Id(), head.Object.Id())
+				newOid, err := repo.CreateCommitFromIds("refs/heads/branch-merged-plus-one", &DefaultAuthor, &DefaultAuthor, "Message", tree.Object.Id(), head.Object.Id())
 				require.NoError(t, err)
-				require.Equal(t, "5da601ef10e314884bbade9d5b063be37579ccf9", newOid.String())
+				require.Equal(t, "8665d9b4b56f6b8ab8c4128a5549d1820bf68bf5", newOid.String())
 			},
 			commitsAhead: 1,
-			expected:     "591b29084164bcc58fa4fb851a3c409290b17bfe",
+			expected:     "56bafb70922008232d171b78930be6cdb722bb39",
 		},
 		{
 			desc:   "With upstream merged into",
@@ -146,9 +145,9 @@ func TestRebase_rebase(t *testing.T) {
 				tree, err := index.WriteTreeTo(repo)
 				require.NoError(t, err)
 
-				newOid, err := repo.CreateCommitFromIds("refs/heads/csv-plus-merge", &cmdtesthelper.DefaultAuthor, &cmdtesthelper.DefaultAuthor, "Message", tree, ours.Object.Id(), theirs.Object.Id())
+				newOid, err := repo.CreateCommitFromIds("refs/heads/csv-plus-merge", &DefaultAuthor, &DefaultAuthor, "Message", tree, ours.Object.Id(), theirs.Object.Id())
 				require.NoError(t, err)
-				require.Equal(t, "5cfe4a597b54c8f2b7ae85212f67599a1492009c", newOid.String())
+				require.Equal(t, "5b2d6bd7be0b1b9f7e46b64d02fe9882c133a128", newOid.String())
 			},
 			commitsAhead: 5, // Same as "Multiple commits"
 			expected:     "2f8365edc69d3683e22c4209ae9641642d84dd4a",
diff --git a/cmd/gitaly-git2go-v15/revert_test.go b/cmd/gitaly-git2go-v15/revert_test.go
index aa85689f5..5cea73d44 100644
--- a/cmd/gitaly-git2go-v15/revert_test.go
+++ b/cmd/gitaly-git2go-v15/revert_test.go
@@ -12,8 +12,9 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"gitlab.com/gitlab-org/gitaly/v15/cmd/gitaly-git2go-v15/git2goutil"
-	cmdtesthelper "gitlab.com/gitlab-org/gitaly/v15/cmd/gitaly-git2go-v15/testhelper"
+	"gitlab.com/gitlab-org/gitaly/v15/internal/git/gittest"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/git2go"
+	"gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/config"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/testhelper"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/testhelper/testcfg"
 )
@@ -77,7 +78,7 @@ func TestRevert_validation(t *testing.T) {
 func TestRevert_trees(t *testing.T) {
 	testcases := []struct {
 		desc             string
-		setupRepo        func(t testing.TB, repoPath string) (ours, revert string)
+		setupRepo        func(t testing.TB, cfg config.Cfg, repoPath string) (ours, revert string)
 		expected         map[string]string
 		expectedCommitID string
 		expectedErr      string
@@ -85,20 +86,21 @@ func TestRevert_trees(t *testing.T) {
 	}{
 		{
 			desc: "trivial revert succeeds",
-			setupRepo: func(t testing.TB, repoPath string) (ours, revert string) {
-				baseOid := cmdtesthelper.BuildCommit(t, repoPath, nil, map[string]string{
-					"a": "apple",
-					"b": "banana",
-				})
-				revertOid := cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{baseOid}, map[string]string{
-					"a": "apple",
-					"b": "pineapple",
-				})
-				oursOid := cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{revertOid}, map[string]string{
-					"a": "apple",
-					"b": "pineapple",
-					"c": "carrot",
-				})
+			setupRepo: func(t testing.TB, cfg config.Cfg, repoPath string) (ours, revert string) {
+				baseOid := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(), gittest.WithTreeEntries(
+					gittest.TreeEntry{Path: "a", Content: "apple", Mode: "100644"},
+					gittest.TreeEntry{Path: "b", Content: "banana", Mode: "100644"},
+				))
+				revertOid := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(baseOid), gittest.WithTreeEntries(
+					gittest.TreeEntry{Path: "a", Content: "apple", Mode: "100644"},
+					gittest.TreeEntry{Path: "b", Content: "pineapple", Mode: "100644"},
+				))
+				oursOid := gittest.WriteCommit(t, cfg, repoPath,
+					gittest.WithParents(revertOid), gittest.WithTreeEntries(
+						gittest.TreeEntry{Path: "a", Content: "apple", Mode: "100644"},
+						gittest.TreeEntry{Path: "b", Content: "pineapple", Mode: "100644"},
+						gittest.TreeEntry{Path: "c", Content: "carrot", Mode: "100644"},
+					))
 
 				return oursOid.String(), revertOid.String()
 			},
@@ -107,20 +109,20 @@ func TestRevert_trees(t *testing.T) {
 				"b": "banana",
 				"c": "carrot",
 			},
-			expectedCommitID: "0be709b57f18ad3f592a8cb7c57f920861392573",
+			expectedCommitID: "c9a58d2273b265cb229f02a5a88037bbdc96ad26",
 		},
 		{
 			desc: "conflicting revert fails",
-			setupRepo: func(t testing.TB, repoPath string) (ours, revert string) {
-				baseOid := cmdtesthelper.BuildCommit(t, repoPath, nil, map[string]string{
-					"a": "apple",
-				})
-				revertOid := cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{baseOid}, map[string]string{
-					"a": "pineapple",
-				})
-				oursOid := cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{revertOid}, map[string]string{
-					"a": "carrot",
-				})
+			setupRepo: func(t testing.TB, cfg config.Cfg, repoPath string) (ours, revert string) {
+				baseOid := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(), gittest.WithTreeEntries(
+					gittest.TreeEntry{Path: "a", Content: "apple", Mode: "100644"},
+				))
+				revertOid := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(baseOid), gittest.WithTreeEntries(
+					gittest.TreeEntry{Path: "a", Content: "pineapple", Mode: "100644"},
+				))
+				oursOid := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(revertOid), gittest.WithTreeEntries(
+					gittest.TreeEntry{Path: "a", Content: "carrot", Mode: "100644"},
+				))
 
 				return oursOid.String(), revertOid.String()
 			},
@@ -129,16 +131,16 @@ func TestRevert_trees(t *testing.T) {
 		},
 		{
 			desc: "empty revert fails",
-			setupRepo: func(t testing.TB, repoPath string) (ours, revert string) {
-				baseOid := cmdtesthelper.BuildCommit(t, repoPath, nil, map[string]string{
-					"a": "apple",
-				})
-				revertOid := cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{baseOid}, map[string]string{
-					"a": "banana",
-				})
-				oursOid := cmdtesthelper.BuildCommit(t, repoPath, []*git.Oid{revertOid}, map[string]string{
-					"a": "apple",
-				})
+			setupRepo: func(t testing.TB, cfg config.Cfg, repoPath string) (ours, revert string) {
+				baseOid := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(), gittest.WithTreeEntries(
+					gittest.TreeEntry{Path: "a", Content: "apple", Mode: "100644"},
+				))
+				revertOid := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(baseOid), gittest.WithTreeEntries(
+					gittest.TreeEntry{Path: "a", Content: "banana", Mode: "100644"},
+				))
+				oursOid := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(revertOid), gittest.WithTreeEntries(
+					gittest.TreeEntry{Path: "a", Content: "apple", Mode: "100644"},
+				))
 
 				return oursOid.String(), revertOid.String()
 			},
@@ -147,10 +149,10 @@ func TestRevert_trees(t *testing.T) {
 		},
 		{
 			desc: "nonexistent ours fails",
-			setupRepo: func(t testing.TB, repoPath string) (ours, revert string) {
-				revertOid := cmdtesthelper.BuildCommit(t, repoPath, nil, map[string]string{
-					"a": "apple",
-				})
+			setupRepo: func(t testing.TB, cfg config.Cfg, repoPath string) (ours, revert string) {
+				revertOid := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(), gittest.WithTreeEntries(
+					gittest.TreeEntry{Path: "a", Content: "apple", Mode: "100644"},
+				))
 
 				return "nonexistent", revertOid.String()
 			},
@@ -158,10 +160,10 @@ func TestRevert_trees(t *testing.T) {
 		},
 		{
 			desc: "nonexistent revert fails",
-			setupRepo: func(t testing.TB, repoPath string) (ours, revert string) {
-				oursOid := cmdtesthelper.BuildCommit(t, repoPath, nil, map[string]string{
-					"a": "apple",
-				})
+			setupRepo: func(t testing.TB, cfg config.Cfg, repoPath string) (ours, revert string) {
+				oursOid := gittest.WriteCommit(t, cfg, repoPath, gittest.WithParents(), gittest.WithTreeEntries(
+					gittest.TreeEntry{Path: "a", Content: "apple", Mode: "100644"},
+				))
 
 				return oursOid.String(), "nonexistent"
 			},
@@ -174,7 +176,7 @@ func TestRevert_trees(t *testing.T) {
 			testcfg.BuildGitalyGit2Go(t, cfg)
 			executor := buildExecutor(t, cfg)
 
-			ours, revert := tc.setupRepo(t, repoPath)
+			ours, revert := tc.setupRepo(t, cfg, repoPath)
 			ctx := testhelper.Context(t)
 
 			authorDate := time.Date(2020, 7, 30, 7, 45, 50, 0, time.FixedZone("UTC+2", +2*60*60))
diff --git a/cmd/gitaly-git2go-v15/testhelper/testhelper.go b/cmd/gitaly-git2go-v15/testhelper/testhelper.go
deleted file mode 100644
index 7ba1e65cd..000000000
--- a/cmd/gitaly-git2go-v15/testhelper/testhelper.go
+++ /dev/null
@@ -1,48 +0,0 @@
-//go:build static && system_libgit2
-// +build static,system_libgit2
-
-package testhelper
-
-import (
-	"testing"
-	"time"
-
-	git "github.com/libgit2/git2go/v33"
-	"github.com/stretchr/testify/require"
-	"gitlab.com/gitlab-org/gitaly/v15/cmd/gitaly-git2go-v15/git2goutil"
-)
-
-// DefaultAuthor is the author used by BuildCommit
-var DefaultAuthor = git.Signature{
-	Name:  "Foo",
-	Email: "foo@example.com",
-	When:  time.Date(2020, 1, 1, 1, 1, 1, 0, time.FixedZone("", 2*60*60)),
-}
-
-//nolint: revive,stylecheck // This is unintentionally missing documentation.
-func BuildCommit(t testing.TB, repoPath string, parents []*git.Oid, fileContents map[string]string) *git.Oid {
-	repo, err := git2goutil.OpenRepository(repoPath)
-	require.NoError(t, err)
-	defer repo.Free()
-
-	odb, err := repo.Odb()
-	require.NoError(t, err)
-
-	treeBuilder, err := repo.TreeBuilder()
-	require.NoError(t, err)
-
-	for file, contents := range fileContents {
-		oid, err := odb.Write([]byte(contents), git.ObjectBlob)
-		require.NoError(t, err)
-		require.NoError(t, treeBuilder.Insert(file, oid, git.FilemodeBlob))
-	}
-
-	tree, err := treeBuilder.Write()
-	require.NoError(t, err)
-
-	var commit *git.Oid
-	commit, err = repo.CreateCommitFromIds("", &DefaultAuthor, &DefaultAuthor, "Message", tree, parents...)
-	require.NoError(t, err)
-
-	return commit
-}
diff --git a/cmd/gitaly-git2go-v15/testhelper_test.go b/cmd/gitaly-git2go-v15/testhelper_test.go
index 39c0dad26..21fc90b13 100644
--- a/cmd/gitaly-git2go-v15/testhelper_test.go
+++ b/cmd/gitaly-git2go-v15/testhelper_test.go
@@ -4,16 +4,41 @@
 package main
 
 import (
+	"fmt"
 	"testing"
+	"time"
 
+	git "github.com/libgit2/git2go/v33"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/git/gittest"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/git2go"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/gitaly/config"
 	"gitlab.com/gitlab-org/gitaly/v15/internal/testhelper"
 )
 
+// DefaultAuthor is the author used by BuildCommit
+var DefaultAuthor = git.Signature{
+	Name:  "Scrooge McDuck",
+	Email: "scrooge@mcduck.com",
+	When:  time.Date(2019, 11, 3, 11, 27, 59, 0, time.FixedZone("", 60*60)),
+}
+
 func TestMain(m *testing.M) {
-	testhelper.Run(m)
+	testhelper.Run(m, testhelper.WithSetup(func() error {
+		// We use Git2go to access repositories in our tests, so we must tell it to ignore
+		// any configuration files that happen to exist. We do the same in `main()`, so
+		// this is not only specific to tests.
+		for _, configLevel := range []git.ConfigLevel{
+			git.ConfigLevelSystem,
+			git.ConfigLevelXDG,
+			git.ConfigLevelGlobal,
+		} {
+			if err := git.SetSearchPath(configLevel, "/dev/null"); err != nil {
+				return fmt.Errorf("setting Git2go search path: %s", err)
+			}
+		}
+
+		return nil
+	}))
 }
 
 func buildExecutor(tb testing.TB, cfg config.Cfg) *git2go.Executor {
diff --git a/internal/command/command.go b/internal/command/command.go
index 4992c6d5b..6dc524e57 100644
--- a/internal/command/command.go
+++ b/internal/command/command.go
@@ -23,20 +23,6 @@ import (
 	"gitlab.com/gitlab-org/labkit/tracing"
 )
 
-func init() {
-	// Prevent the environment from affecting git calls by ignoring the configuration files.
-	//
-	// This should be done always but we have to wait until 15.0 due to backwards compatibility
-	// concerns. To fix tests ahead to 15.0, we ignore the global configuration when the package
-	// has been built under tests. `go test` uses a `.test` suffix on the test binaries. We use
-	// that to check whether to ignore the globals or not.
-	//
-	// See https://gitlab.com/gitlab-org/gitaly/-/issues/3617.
-	if strings.HasSuffix(os.Args[0], ".test") {
-		GitEnv = append(GitEnv, "GIT_CONFIG_GLOBAL=/dev/null", "GIT_CONFIG_SYSTEM=/dev/null")
-	}
-}
-
 var (
 	cpuSecondsTotal = promauto.NewCounterVec(
 		prometheus.CounterOpts{
@@ -89,18 +75,6 @@ var (
 	)
 )
 
-// GitEnv contains the ENV variables for git commands
-var GitEnv = []string{
-	// Force english locale for consistency on the output messages
-	"LANG=en_US.UTF-8",
-
-	//
-	// PLEASE NOTE: the init of this package adds rules to ignore global git configuration in
-	// tests. This should really be done always but we can't do this before 15.0 due to backwards
-	// compatibility concerns. See https://gitlab.com/gitlab-org/gitaly/-/issues/3617.
-	//
-}
-
 // exportedEnvVars contains a list of environment variables
 // that are always exported to child processes on spawn
 var exportedEnvVars = []string{
@@ -275,11 +249,11 @@ func New(ctx context.Context, cmd *exec.Cmd, stdin io.Reader, stdout, stderr io.
 		span:      span,
 	}
 
-	// Explicitly set the environment for the command
-	env = append(env, "GIT_TERMINAL_PROMPT=0")
-
-	// Export env vars
-	cmd.Env = append(AllowedEnvironment(os.Environ()), env...)
+	// Export allowed environment variables as set in the Gitaly process.
+	cmd.Env = AllowedEnvironment(os.Environ())
+	// Append environment variables explicitly requested by thecaller.
+	cmd.Env = append(cmd.Env, env...)
+	// And finally inject environment variables required for tracing into the command.
 	cmd.Env = envInjector(ctx, cmd.Env)
 
 	// Start the command in its own process group (nice for signalling)
diff --git a/internal/git/command_factory.go b/internal/git/command_factory.go
index a5d127019..17b2a85de 100644
--- a/internal/git/command_factory.go
+++ b/internal/git/command_factory.go
@@ -7,6 +7,7 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+	"strings"
 	"sync"
 
 	"github.com/prometheus/client_golang/prometheus"
@@ -147,9 +148,33 @@ func NewExecCommandFactory(cfg config.Cfg, opts ...ExecCommandFactoryOption) (_
 // setupGitExecutionEnvironments assembles a Git execution environment that can be used to run Git
 // commands. It warns if no path was specified in the configuration.
 func setupGitExecutionEnvironments(cfg config.Cfg, factoryCfg execCommandFactoryConfig) ([]ExecutionEnvironment, func(), error) {
+	sharedEnvironment := []string{
+		// Force English locale for consistency on output messages and to help us debug in
+		// case we get bug reports from customers whose system-locale would be different.
+		"LANG=en_US.UTF-8",
+		// Ask Git to never prompt us for any information like e.g. credentials.
+		"GIT_TERMINAL_PROMPT=0",
+	}
+
+	// Prevent the environment from affecting git calls by ignoring the configuration files.
+	//
+	// This should be done always but we have to wait until 15.0 due to backwards compatibility
+	// concerns. To fix tests ahead to 15.0, we ignore the global configuration when the package
+	// has been built under tests. `go test` uses a `.test` suffix on the test binaries. We use
+	// that to check whether to ignore the globals or not.
+	//
+	// See https://gitlab.com/gitlab-org/gitaly/-/issues/3617.
+	if strings.HasSuffix(os.Args[0], ".test") {
+		sharedEnvironment = append(sharedEnvironment,
+			"GIT_CONFIG_GLOBAL=/dev/null",
+			"GIT_CONFIG_SYSTEM=/dev/null",
+			"XDG_CONFIG_HOME=/dev/null",
+		)
+	}
+
 	if factoryCfg.gitBinaryPath != "" {
 		return []ExecutionEnvironment{
-			{BinaryPath: factoryCfg.gitBinaryPath},
+			{BinaryPath: factoryCfg.gitBinaryPath, EnvironmentVariables: sharedEnvironment},
 		}, func() {}, nil
 	}
 
@@ -168,6 +193,8 @@ func setupGitExecutionEnvironments(cfg config.Cfg, factoryCfg execCommandFactory
 			return nil, nil, fmt.Errorf("constructing Git environment: %w", err)
 		}
 
+		execEnv.EnvironmentVariables = append(execEnv.EnvironmentVariables, sharedEnvironment...)
+
 		execEnvs = append(execEnvs, execEnv)
 	}
 
@@ -369,7 +396,6 @@ func (cf *ExecCommandFactory) newCommand(ctx context.Context, repo repository.Gi
 
 	execEnv := cf.GetExecutionEnvironment(ctx)
 
-	env = append(env, command.GitEnv...)
 	env = append(env, execEnv.EnvironmentVariables...)
 
 	execCommand := exec.Command(execEnv.BinaryPath, args...)
diff --git a/internal/git/command_factory_test.go b/internal/git/command_factory_test.go
index 06d3f0762..3c3aec4fb 100644
--- a/internal/git/command_factory_test.go
+++ b/internal/git/command_factory_test.go
@@ -170,6 +170,13 @@ func TestCommandFactory_ExecutionEnvironment(t *testing.T) {
 			Git: config.Git{BinPath: "/path/to/myGit"},
 		}, git.ExecutionEnvironment{
 			BinaryPath: "/path/to/myGit",
+			EnvironmentVariables: []string{
+				"LANG=en_US.UTF-8",
+				"GIT_TERMINAL_PROMPT=0",
+				"GIT_CONFIG_GLOBAL=/dev/null",
+				"GIT_CONFIG_SYSTEM=/dev/null",
+				"XDG_CONFIG_HOME=/dev/null",
+			},
 		})
 	})
 
@@ -178,6 +185,13 @@ func TestCommandFactory_ExecutionEnvironment(t *testing.T) {
 
 		assertExecEnv(t, config.Cfg{Git: config.Git{}}, git.ExecutionEnvironment{
 			BinaryPath: "/path/to/env_git",
+			EnvironmentVariables: []string{
+				"LANG=en_US.UTF-8",
+				"GIT_TERMINAL_PROMPT=0",
+				"GIT_CONFIG_GLOBAL=/dev/null",
+				"GIT_CONFIG_SYSTEM=/dev/null",
+				"XDG_CONFIG_HOME=/dev/null",
+			},
 		})
 	})
 
@@ -271,6 +285,13 @@ func TestCommandFactory_ExecutionEnvironment(t *testing.T) {
 
 		assertExecEnv(t, config.Cfg{}, git.ExecutionEnvironment{
 			BinaryPath: resolvedPath,
+			EnvironmentVariables: []string{
+				"LANG=en_US.UTF-8",
+				"GIT_TERMINAL_PROMPT=0",
+				"GIT_CONFIG_GLOBAL=/dev/null",
+				"GIT_CONFIG_SYSTEM=/dev/null",
+				"XDG_CONFIG_HOME=/dev/null",
+			},
 		})
 	})
 
diff --git a/internal/git/gittest/command.go b/internal/git/gittest/command.go
index 751f4ee54..b31e57cd3 100644
--- a/internal/git/gittest/command.go
+++ b/internal/git/gittest/command.go
@@ -62,7 +62,6 @@ func createCommand(t testing.TB, cfg config.Cfg, execCfg ExecConfig, args ...str
 
 	cmd := exec.CommandContext(ctx, execEnv.BinaryPath, args...)
 	cmd.Env = command.AllowedEnvironment(os.Environ())
-	cmd.Env = append(command.GitEnv, cmd.Env...)
 	cmd.Env = append(cmd.Env,
 		"GIT_AUTHOR_DATE=1572776879 +0100",
 		"GIT_COMMITTER_DATE=1572776879 +0100",
diff --git a/internal/git2go/executor.go b/internal/git2go/executor.go
index d1ab916a1..899c7e64e 100644
--- a/internal/git2go/executor.go
+++ b/internal/git2go/executor.go
@@ -56,6 +56,7 @@ func (b *Executor) run(ctx context.Context, repo repository.GitRepo, stdin io.Re
 	}
 
 	env := alternates.Env(repoPath, repo.GetGitObjectDirectory(), repo.GetGitAlternateObjectDirectories())
+	env = append(env, b.gitCmdFactory.GetExecutionEnvironment(ctx).EnvironmentVariables...)
 
 	// Pass the log output directly to gitaly-git2go. No need to reinterpret
 	// these logs as long as the destination is an append-only file. See
diff --git a/internal/gitaly/rubyserver/rubyserver.go b/internal/gitaly/rubyserver/rubyserver.go
index 1ae315cb3..5ac213e72 100644
--- a/internal/gitaly/rubyserver/rubyserver.go
+++ b/internal/gitaly/rubyserver/rubyserver.go
@@ -61,7 +61,6 @@ func setupEnv(cfg config.Cfg, gitCmdFactory git.CommandFactory) ([]string, error
 		"GITALY_TOKEN="+cfg.Auth.Token,
 		"GITALY_RUGGED_GIT_CONFIG_SEARCH_PATH="+cfg.Ruby.RuggedGitConfigSearchPath,
 	)
-	environment = append(environment, command.GitEnv...)
 	environment = append(environment, gitExecEnv.EnvironmentVariables...)
 	environment = append(environment, env.AllowedRubyEnvironment(os.Environ())...)
 
diff --git a/internal/testhelper/testcfg/build.go b/internal/testhelper/testcfg/build.go
index a39a409f4..59ab9ee7a 100644
--- a/internal/testhelper/testcfg/build.go
+++ b/internal/testhelper/testcfg/build.go
@@ -100,18 +100,7 @@ func BuildBinary(t testing.TB, targetDir, sourcePath string) string {
 		// We need to filter out some environments we set globally in our tests which would
 		// cause Git to not operate correctly.
 		for _, env := range os.Environ() {
-			shouldExclude := false
-			for _, prefix := range []string{
-				"GIT_DIR=",
-				"GIT_CONFIG_GLOBAL=",
-				"GIT_CONFIG_SYSTEM=",
-			} {
-				if strings.HasPrefix(env, prefix) {
-					shouldExclude = true
-					break
-				}
-			}
-			if !shouldExclude {
+			if !strings.HasPrefix(env, "GIT_DIR=") {
 				gitEnvironment = append(gitEnvironment, env)
 			}
 		}
diff --git a/ruby/bin/gitaly-ruby b/ruby/bin/gitaly-ruby
index d37352945..c0f17b1e5 100755
--- a/ruby/bin/gitaly-ruby
+++ b/ruby/bin/gitaly-ruby
@@ -73,6 +73,8 @@ def set_rugged_search_path
   return unless search_path
 
   Rugged::Settings['search_path_system'] = search_path
+  Rugged::Settings['search_path_global'] = '/dev/null'
+  Rugged::Settings['search_path_xdg'] = '/dev/null'
 end
 
 def load_distributed_tracing
diff --git a/ruby/spec/spec_helper.rb b/ruby/spec/spec_helper.rb
index 52296007e..dcd20550e 100644
--- a/ruby/spec/spec_helper.rb
+++ b/ruby/spec/spec_helper.rb
@@ -13,6 +13,12 @@ GITLAB_SHELL_DIR = File.join(TMP_DIR, 'gitlab-shell').freeze
 # overwrite HOME env variable so user global .gitconfig doesn't influence tests
 ENV["HOME"] = File.join(File.dirname(__FILE__), "/support/helpers/testdata/home")
 
+# Furthermore, overwrite the Rugged search path so that it doesn't pick up any
+# gitconfig, either.
+Rugged::Settings['search_path_system'] = '/dev/null'
+Rugged::Settings['search_path_global'] = '/dev/null'
+Rugged::Settings['search_path_xdg'] = '/dev/null'
+
 require 'test_repo_helper'
 
 Dir[File.join(__dir__, 'support/helpers/*.rb')].each { |f| require f }