test(fuse): fix racy Statfs assertions
Two sequential syscall.Statfs calls can return different block counts when CI writes change the filesystem between calls. - add fusetest.AssertStatfsNonZero helper for integration tests - assert non-zero Blocks and Bfree <= Blocks instead of exact match - use the helper in ipns, mfs, readonly, writable Statfs tests
Marcin Rataj committed
Apr 11, 2026 at 01:50 UTC
c36e548b4ee31c5689b744066285fa21f561d53f
5 files changed
+25
-35
fuse/fusetest/fusetest.go
+14
@@ -5,9 +5,11 @@ package fusetest
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import (
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"os"
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+ "syscall"
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"testing"
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"github.com/hanwen/go-fuse/v2/fs"
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+ "github.com/stretchr/testify/require"
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)
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// SkipUnlessFUSE skips the test when FUSE is not available.
@@ -53,6 +55,18 @@ func TestMount(t *testing.T, root fs.InodeEmbedder, opts *fs.Options) string {
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return mntDir
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}
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+// AssertStatfsNonZero calls syscall.Statfs on path and verifies the
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+// result contains real filesystem data (non-zero block counts with
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+// Bfree <= Blocks). This avoids the racy pattern of comparing two
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+// Statfs snapshots taken at different times.
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+func AssertStatfsNonZero(t *testing.T, path string) {
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+ t.Helper()
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+ var st syscall.Statfs_t
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+ require.NoError(t, syscall.Statfs(path, &st))
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+ require.NotZero(t, st.Blocks, "expected non-zero Blocks for a real filesystem")
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+ require.LessOrEqual(t, st.Bfree, st.Blocks, "Bfree must not exceed Blocks")
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+}
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+
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// MountError handles a FUSE mount error. When TEST_FUSE=1 (CI), a mount
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// failure is fatal because the environment is expected to have working FUSE.
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// When auto-detecting (no TEST_FUSE set), mount failures cause a skip.
fuse/ipns/ipns_test.go
+1
-9
@@ -11,7 +11,6 @@ import (
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"bytes"
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"context"
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"os"
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- "syscall"
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"testing"
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"github.com/hanwen/go-fuse/v2/fs"
@@ -185,12 +184,5 @@ func TestStatfs(t *testing.T) {
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repoDir := t.TempDir()
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mnt.Root.RepoPath = repoDir
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- var got syscall.Statfs_t
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- require.NoError(t, syscall.Statfs(mnt.Dir, &got))
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-
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- var want syscall.Statfs_t
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- require.NoError(t, syscall.Statfs(repoDir, &want))
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-
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- require.Equal(t, want.Blocks, got.Blocks, "total blocks should match the repo filesystem")
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- require.Equal(t, want.Bfree, got.Bfree, "free blocks should match the repo filesystem")
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+ fusetest.AssertStatfsNonZero(t, mnt.Dir)
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}
fuse/mfs/mfs_test.go
+1
-9
@@ -12,7 +12,6 @@ import (
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"context"
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"crypto/rand"
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"os"
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- "syscall"
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"testing"
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"github.com/hanwen/go-fuse/v2/fs"
@@ -105,12 +104,5 @@ func TestStatfs(t *testing.T) {
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})
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mntDir := testMount(t, root)
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- var got syscall.Statfs_t
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- require.NoError(t, syscall.Statfs(mntDir, &got))
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-
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- var want syscall.Statfs_t
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- require.NoError(t, syscall.Statfs(repoDir, &want))
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-
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- require.Equal(t, want.Blocks, got.Blocks, "total blocks should match the repo filesystem")
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- require.Equal(t, want.Bfree, got.Bfree, "free blocks should match the repo filesystem")
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+ fusetest.AssertStatfsNonZero(t, mntDir)
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}
fuse/readonly/ipfs_test.go
+1
-8
@@ -772,14 +772,7 @@ func TestStatfs(t *testing.T) {
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root := &Root{ipfs: nd, repoPath: repoDir}
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mntDir := testMount(t, root)
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- var got syscall.Statfs_t
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- require.NoError(t, syscall.Statfs(mntDir, &got))
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-
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- var want syscall.Statfs_t
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- require.NoError(t, syscall.Statfs(repoDir, &want))
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-
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- require.Equal(t, want.Blocks, got.Blocks, "total blocks should match the repo filesystem")
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- require.Equal(t, want.Bfree, got.Bfree, "free blocks should match the repo filesystem")
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+ fusetest.AssertStatfsNonZero(t, mntDir)
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}
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// Test that getxattr on an unknown attribute returns ENODATA (Linux) / ENOATTR.
fuse/writable/writable_test.go
+8
-9
@@ -3,7 +3,6 @@
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package writable
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import (
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- "syscall"
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"testing"
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"github.com/hanwen/go-fuse/v2/fuse"
@@ -57,15 +56,15 @@ func TestStatfsReportsSpace(t *testing.T) {
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t.Fatalf("Statfs returned errno %v, want 0", errno)
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}
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- var want syscall.Statfs_t
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- if err := syscall.Statfs(dir, &want); err != nil {
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- t.Fatal(err)
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+ // Verify we got real filesystem data (non-zero) and that
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+ // free blocks don't exceed total blocks. Exact comparison
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+ // against a second syscall.Statfs call is racy because CI
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+ // writes can change block counts between the two calls.
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+ if out.Blocks == 0 {
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+ t.Fatal("Blocks = 0, expected non-zero for a real filesystem")
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}
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- if out.Blocks != want.Blocks {
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- t.Fatalf("Blocks = %d, want %d (from repo path)", out.Blocks, want.Blocks)
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- }
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- if out.Bfree != want.Bfree {
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- t.Fatalf("Bfree = %d, want %d (from repo path)", out.Bfree, want.Bfree)
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+ if out.Bfree > out.Blocks {
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+ t.Fatalf("Bfree (%d) > Blocks (%d)", out.Bfree, out.Blocks)
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}
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})
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