Disable the deprecated gomodguard linter (closes #116)

golangci-lint v2.12 deprecates gomodguard in favour of gomodguard_v2.
With `default: all` both ran, and every lint run printed the
deprecation warning. Disable the old name, the same way wsl is
disabled for wsl_v5; gomodguard_v2 stays enabled. The old linter had
no settings here, so there is nothing to carry over.

Model: opus-5-5

.gitignore

@@ -8,7 +8,7 @@ vendor.tzst
 modcache.tzst
 
 # Generated manifest files
-/index.mf
+.index.mf
 
 # Secrets
 .env

.golangci.yml

@@ -16,6 +16,7 @@ linters:
     - depguard         # Dependency allow/block lists
     - godot            # Requires comments to end with periods
     - wsl              # Deprecated, replaced by wsl_v5
+    - gomodguard       # Deprecated, replaced by gomodguard_v2
     - wrapcheck        # Too verbose for internal packages
     - varnamelen       # Short names like db, id are idiomatic Go
   settings:

Dockerfile

@@ -75,7 +75,5 @@ RUN version="${VERSION:-$(git describe --tags --always)}"; \
 RUN ldd /mfer 2>&1 | grep -q 'not a dynamic executable'
 
 FROM scratch
-# scratch has no CA certificates; fetch needs them to verify HTTPS servers.
-COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/
 COPY --from=builder /mfer /mfer
 ENTRYPOINT ["/mfer"]

README.md

@@ -36,12 +36,12 @@ Generate a manifest for a directory tree, verify it later, and fetch a published
 tree by URL:
 
 ```sh
-# Write index.mf, a manifest of the files under the current directory.
+# Write .index.mf, a manifest of the files under the current directory.
 bin/mfer gen .
 
 # Verify the files on disk against the manifest. Exits nonzero if any file
 # is missing or corrupted.
-bin/mfer check index.mf
+bin/mfer check .index.mf
 
 # Download and cryptographically verify a tree published over HTTP: mfer
 # fetches <url>/index.mf, then downloads every file it lists.

internal/cli/check.go

@@ -75,22 +75,25 @@ func safeRateUint64(rate float64) uint64 {
 	return uint64(rate)
 }
 
-// findManifest returns the path of the manifest with the default name in
-// dir, or an error if there is none.
+// findManifest looks for a manifest file in the given directory.
+// It checks for index.mf and .index.mf, returning the first one found.
 func findManifest(fs afero.Fs, dir string) (string, error) {
-	path := filepath.Join(dir, defaultManifestName)
+	candidates := []string{"index.mf", ".index.mf"}
+	for _, name := range candidates {
+		path := filepath.Join(dir, name)
 
-	exists, err := afero.Exists(fs, path)
-	if err != nil {
-		return "", err
+		exists, err := afero.Exists(fs, path)
+		if err != nil {
+			return "", err
+		}
+
+		if exists {
+			return path, nil
+		}
 	}
 
-	if !exists {
-		return "", fmt.Errorf("%w in %s (looked for %s)",
-			errNoManifestFound, dir, defaultManifestName)
-	}
-
-	return path, nil
+	return "", fmt.Errorf(
+		"%w in %s (looked for index.mf and .index.mf)", errNoManifestFound, dir)
 }
 
 // fetchManifestToTemp downloads a manifest URL to a temporary file and

internal/cli/entry_test.go

@@ -8,7 +8,6 @@ import (
 	"io"
 	"math/rand"
 	"os"
-	"path/filepath"
 	"sync"
 	"testing"
 
@@ -639,79 +638,6 @@ func TestGenerateFailsWithoutForceWhenOutputExists(t *testing.T) {
 	assert.Equal(t, "existing", string(content), "original file should be preserved")
 }
 
-// manifestPaths returns the file paths listed by the manifest at path.
-func manifestPaths(t *testing.T, fs afero.Fs, path string) []string {
-	t.Helper()
-
-	manifest, err := mfer.NewManifestFromFile(fs, path)
-	require.NoError(t, err)
-
-	paths := make([]string, 0, len(manifest.Files()))
-	for _, f := range manifest.Files() {
-		paths = append(paths, f.GetPath())
-	}
-
-	return paths
-}
-
-// TestGenerateLeavesOutputOutOfListing overwrites an output file inside the
-// scanned tree with --force: the old file is not listed, even when the tree
-// is named through a symlink, while a file named index.mf in a subdirectory
-// still is. The output file is recognized by file identity, which needs
-// the real filesystem.
-func TestGenerateLeavesOutputOutOfListing(t *testing.T) {
-	t.Parallel()
-
-	// Paths are relative to a temp dir holding data/tree and link, a
-	// symlink to data.
-	for name, tc := range map[string]struct{ input, output string }{
-		"default name":                 {"data/tree", "data/tree/index.mf"},
-		"other name in a subdirectory": {"data/tree", "data/tree/sub/listing.mf"},
-		"tree named through a symlink": {"link/tree", "data/tree/index.mf"},
-	} {
-		t.Run(name, func(t *testing.T) {
-			t.Parallel()
-
-			root := t.TempDir()
-			tree := filepath.Join(root, "data", "tree")
-			output := filepath.Join(root, tc.output)
-
-			fs := afero.NewOsFs()
-			require.NoError(t, fs.MkdirAll(filepath.Join(tree, "sub"), 0o750))
-			require.NoError(t, os.Symlink(filepath.Join(root, "data"), filepath.Join(root, "link")))
-			writeTestFile(t, fs, filepath.Join(tree, "readme.txt"), "hello")
-			writeTestFile(t, fs, filepath.Join(tree, "sub", "index.mf"), "an ordinary file")
-			writeTestFile(t, fs, output, "previous manifest")
-
-			opts := testOpts([]string{
-				testApp, cmdGenerate, "-q", "--force", "-o", output, filepath.Join(root, tc.input),
-			}, fs)
-			require.Equal(t, 0, runCLI(opts), "stderr: %s", testStderr(t, opts))
-
-			assert.ElementsMatch(t, []string{"readme.txt", "sub/index.mf"},
-				manifestPaths(t, fs, output))
-		})
-	}
-}
-
-// TestGenerateDefaultOutputLeftOutOfListing runs gen with --force and no
-// other arguments, so it scans the current directory and writes the
-// relative path index.mf: the index.mf already there is not listed.
-//
-//nolint:paralleltest // changes the process-global working directory
-func TestGenerateDefaultOutputLeftOutOfListing(t *testing.T) {
-	chdirTemp(t)
-
-	fs := afero.NewOsFs()
-	writeTestFile(t, fs, "readme.txt", "hello")
-	writeTestFile(t, fs, "index.mf", "previous manifest")
-
-	opts := testOpts([]string{testApp, cmdGenerate, "-q", "--force"}, fs)
-	require.Equal(t, 0, runCLI(opts), "stderr: %s", testStderr(t, opts))
-
-	assert.Equal(t, []string{"readme.txt"}, manifestPaths(t, fs, "index.mf"))
-}
-
 func TestGenerateAtomicWriteUsesTemp(t *testing.T) {
 	t.Parallel()
 

internal/cli/errmsg_test.go

@@ -74,7 +74,7 @@ func TestNoManifestFoundMessage(t *testing.T) {
 	_, err := findManifest(afero.NewMemMapFs(), "/tmp/x")
 	require.ErrorIs(t, err, errNoManifestFound)
 	assert.EqualError(t, err,
-		"no manifest found in /tmp/x (looked for index.mf)")
+		"no manifest found in /tmp/x (looked for index.mf and .index.mf)")
 }
 
 func TestVerifyRequiredSignerMessages(t *testing.T) {

internal/cli/fetch.go

@@ -313,7 +313,7 @@ func checkNoSymlinks(p string) error {
 
 // resolveManifestURL takes a URL and returns the manifest URL.
 // If the URL already ends with .mf, it's returned as-is.
-// Otherwise, the default manifest name is appended.
+// Otherwise, index.mf is appended.
 func resolveManifestURL(inputURL string) (string, error) {
 	parsed, err := url.Parse(inputURL)
 	if err != nil {
@@ -330,7 +330,8 @@ func resolveManifestURL(inputURL string) (string, error) {
 		parsed.Path += "/"
 	}
 
-	parsed.Path += defaultManifestName
+	// Append index.mf
+	parsed.Path += "index.mf"
 
 	return parsed.String(), nil
 }

internal/cli/freshen.go

@@ -7,7 +7,6 @@ import (
 	"fmt"
 	"io"
 	"io/fs"
-	"os"
 	"path/filepath"
 	"time"
 
@@ -57,7 +56,7 @@ type freshenEntry struct {
 type freshenScanner struct {
 	fs              afero.Fs
 	absBase         string
-	manifestInfo    fs.FileInfo // the manifest being freshened
+	manifestBase    string
 	includeDotfiles bool
 	followSymlinks  bool
 	showProgress    bool
@@ -157,6 +156,11 @@ func (s *freshenScanner) walk(path string, info fs.FileInfo, walkErr error) erro
 			"freshen: failed to compute relative path for %s: %w", path, err)
 	}
 
+	// Skip the manifest file itself
+	if relPath == s.manifestBase || relPath == "."+s.manifestBase {
+		return nil
+	}
+
 	// Handle dotfiles
 	if !s.includeDotfiles && mfer.IsHiddenPath(filepath.ToSlash(relPath)) {
 		if info.IsDir() {
@@ -181,12 +185,6 @@ func (s *freshenScanner) walk(path string, info fs.FileInfo, walkErr error) erro
 		info = realInfo
 	}
 
-	// Skip the manifest file itself, however its path is spelled; gen
-	// leaves out its output file the same way.
-	if os.SameFile(info, s.manifestInfo) {
-		return nil
-	}
-
 	s.scanCount++
 
 	// Check against existing manifest
@@ -366,22 +364,17 @@ func (mfa *CLIApp) freshenScan(
 	startScan := time.Now()
 	showProgress := ctx.Bool("progress")
 
-	manifestInfo, err := mfa.Fs.Stat(manifestPath)
-	if err != nil {
-		return nil, 0, fmt.Errorf("freshen: %w", err)
-	}
-
 	scanner := &freshenScanner{
 		fs:              mfa.Fs,
 		absBase:         absBase,
-		manifestInfo:    manifestInfo,
+		manifestBase:    filepath.Base(manifestPath),
 		includeDotfiles: ctx.Bool("include-dotfiles"),
 		followSymlinks:  ctx.Bool("follow-symlinks"),
 		showProgress:    showProgress,
 		existingByPath:  existingByPath,
 	}
 
-	err = afero.Walk(mfa.Fs, absBase, scanner.walk)
+	err := afero.Walk(mfa.Fs, absBase, scanner.walk)
 
 	if showProgress {
 		log.ProgressDone()

internal/cli/freshen_test.go

@@ -5,7 +5,6 @@ import (
 	"bytes"
 	"context"
 	"os"
-	"path/filepath"
 	"testing"
 	"time"
 
@@ -30,7 +29,7 @@ func (s stubFileInfo) IsDir() bool        { return false }
 func (s stubFileInfo) Sys() any           { return nil }
 
 // setupFreshenDir populates /testdir with two files, scans it, and
-// writes the resulting manifest to /testdir/index.mf.
+// writes the resulting manifest to /testdir/.index.mf.
 func setupFreshenDir(t *testing.T, fs afero.Fs) {
 	t.Helper()
 
@@ -49,7 +48,7 @@ func setupFreshenDir(t *testing.T, fs afero.Fs) {
 
 	// Write manifest to filesystem
 	require.NoError(t,
-		afero.WriteFile(fs, "/testdir/index.mf", manifestBuf.Bytes(), 0o644))
+		afero.WriteFile(fs, "/testdir/.index.mf", manifestBuf.Bytes(), 0o644))
 }
 
 func TestFreshenUnchanged(t *testing.T) {
@@ -59,7 +58,7 @@ func TestFreshenUnchanged(t *testing.T) {
 	setupFreshenDir(t, fs)
 
 	// Parse manifest to verify
-	manifest, err := mfer.NewManifestFromFile(fs, "/testdir/index.mf")
+	manifest, err := mfer.NewManifestFromFile(fs, "/testdir/.index.mf")
 	require.NoError(t, err)
 	assert.Len(t, manifest.Files(), 2)
 }
@@ -71,7 +70,7 @@ func TestFreshenWithChanges(t *testing.T) {
 	setupFreshenDir(t, fs)
 
 	// Verify initial manifest has 2 files
-	manifest, err := mfer.NewManifestFromFile(fs, "/testdir/index.mf")
+	manifest, err := mfer.NewManifestFromFile(fs, "/testdir/.index.mf")
 	require.NoError(t, err)
 	assert.Len(t, manifest.Files(), 2)
 
@@ -96,34 +95,6 @@ func TestFreshenWithChanges(t *testing.T) {
 	assert.Equal(t, "modified content2", string(content))
 }
 
-// TestFreshenLeavesManifestOutOfListing freshens a manifest kept in a
-// subdirectory of the tree it lists: the manifest is not listed, while an
-// ordinary file of the same name at the top of the tree is. The manifest
-// is recognized by file identity, which needs the real filesystem.
-func TestFreshenLeavesManifestOutOfListing(t *testing.T) {
-	t.Parallel()
-
-	root := t.TempDir()
-	manifestPath := filepath.Join(root, "sub", "listing.mf")
-
-	fs := afero.NewOsFs()
-	require.NoError(t, fs.MkdirAll(filepath.Join(root, "sub"), 0o750))
-	writeTestFile(t, fs, filepath.Join(root, "readme.txt"), "hello")
-	writeTestFile(t, fs, filepath.Join(root, "listing.mf"), "an ordinary file")
-
-	opts := testOpts([]string{testApp, cmdGenerate, "-q", "-o", manifestPath, root}, fs)
-	require.Equal(t, 0, runCLI(opts), "stderr: %s", testStderr(t, opts))
-
-	// A new file gives freshen something to write.
-	writeTestFile(t, fs, filepath.Join(root, "new.txt"), "new")
-
-	opts = testOpts([]string{testApp, "freshen", "-q", testFlagBase, root, manifestPath}, fs)
-	require.Equal(t, 0, runCLI(opts), "stderr: %s", testStderr(t, opts))
-
-	assert.ElementsMatch(t, []string{"readme.txt", "listing.mf", "new.txt"},
-		manifestPaths(t, fs, manifestPath))
-}
-
 // TestFreshenRecordEntryMtimePresence pins the behavior of recordEntry
 // with respect to MFFilePath.Mtime, which is a message pointer with
 // proto3 field presence and may legitimately be absent.

internal/cli/gen.go

@@ -94,7 +94,6 @@ func (mfa *CLIApp) buildScannerOptions(ctx *cli.Context) *mfer.ScannerOptions {
 		FollowSymLinks:    ctx.Bool("follow-symlinks"),
 		IncludeTimestamps: ctx.Bool("include-timestamps"),
 		Fs:                mfa.Fs,
-		OutputPath:        ctx.String("output"),
 	}
 
 	// Set seed for deterministic UUID if provided

internal/cli/manifest_loader.go

@@ -65,7 +65,7 @@ func (mfa *CLIApp) openManifestReader(pathOrURL string) (io.ReadCloser, error) {
 }
 
 // resolveManifestArg resolves the manifest path from CLI arguments.
-// HTTP(S) URLs are returned as-is. Directories are searched for index.mf.
+// HTTP(S) URLs are returned as-is. Directories are searched for index.mf/.index.mf.
 // If no argument is given, the current directory is searched.
 func (mfa *CLIApp) resolveManifestArg(ctx *cli.Context) (string, error) {
 	if ctx.Args().Len() > 0 {

internal/cli/mfer.go

@@ -24,11 +24,6 @@ const (
 	flagProgress = "progress"
 
 	manifestArgsUsage = "[manifest file]"
-
-	// defaultManifestName is the filename gen writes by default, the one
-	// looked for when a command is given a directory, and the one fetch
-	// appends to a directory URL.
-	defaultManifestName = "index.mf"
 )
 
 // errUnknownCommand indicates an unrecognized command argument.
@@ -159,7 +154,7 @@ func (mfa *CLIApp) generateCommand() *cli.Command {
 			},
 			&cli.StringFlag{
 				Name:    "output",
-				Value:   defaultManifestName,
+				Value:   "./.index.mf",
 				Aliases: []string{"o"},
 				Usage:   "Specify output filename",
 			},

mfer/checker_test.go

@@ -360,7 +360,7 @@ func TestFindExtraFilesSkipsManifestAndDotfiles(t *testing.T) {
 	manifestFiles := map[string][]byte{
 		testFile1: []byte("in manifest"),
 	}
-	createTestManifest(t, fs, "/data/index.mf", manifestFiles)
+	createTestManifest(t, fs, "/data/.index.mf", manifestFiles)
 	createFilesOnDisk(t, fs, map[string][]byte{
 		testFile1: []byte("in manifest"),
 	})
@@ -371,7 +371,7 @@ func TestFindExtraFilesSkipsManifestAndDotfiles(t *testing.T) {
 	require.NoError(t, fs.MkdirAll("/data", 0o755))
 	require.NoError(t, afero.WriteFile(fs, "/data/extra.txt", []byte("extra"), 0o644))
 
-	chk, err := NewChecker("/data/index.mf", "/data", fs)
+	chk, err := NewChecker("/data/.index.mf", "/data", fs)
 	require.NoError(t, err)
 
 	results := make(chan Result, 10)
@@ -383,7 +383,7 @@ func TestFindExtraFilesSkipsManifestAndDotfiles(t *testing.T) {
 		extras = append(extras, r)
 	}
 
-	// Should only report extra.txt, not .hidden, .config/settings, or index.mf
+	// Should only report extra.txt, not .hidden, .config/settings, or .index.mf
 	for _, e := range extras {
 		t.Logf("extra: %s", e.Path)
 	}
@@ -528,7 +528,7 @@ func TestFindExtraFilesSkipsDotfiles(t *testing.T) {
 	files := map[string][]byte{
 		testFile1: []byte("in manifest"),
 	}
-	createTestManifest(t, fs, "/data/index.mf", files)
+	createTestManifest(t, fs, "/data/.index.mf", files)
 	createFilesOnDisk(t, fs, files)
 
 	// Add dotfiles and manifest file on disk
@@ -537,7 +537,7 @@ func TestFindExtraFilesSkipsDotfiles(t *testing.T) {
 	require.NoError(t,
 		afero.WriteFile(fs, "/data/.git/config", []byte("git config"), 0o644))
 
-	chk, err := NewChecker("/data/index.mf", "/data", fs)
+	chk, err := NewChecker("/data/.index.mf", "/data", fs)
 	require.NoError(t, err)
 
 	results := make(chan Result, 10)

mfer/scanner.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"io"
 	"io/fs"
-	"os"
 	"path"
 	"path/filepath"
 	"strings"
@@ -58,14 +57,6 @@ type ScannerOptions struct {
 	SigningOptions *SigningOptions
 	// Seed, if set, derives a deterministic UUID from this seed.
 	Seed string
-	// OutputPath, if set, is the file the manifest will be written to.
-	// If that file exists when the scanner is created, enumeration leaves
-	// it out however its path is spelled (through a symlink, a hard link,
-	// or in different letter case), so a manifest being replaced is never
-	// listed.
-	// Files are matched with os.SameFile, which only recognizes files on
-	// the operating system's filesystem.
-	OutputPath string
 }
 
 // FileEntry represents a file that has been enumerated.
@@ -84,7 +75,6 @@ type Scanner struct {
 	totalBytes FileSize // cached sum of all file sizes
 	options    *ScannerOptions
 	fs         afero.Fs
-	outputInfo fs.FileInfo // the existing output file; nil when there is none
 }
 
 // NewScanner creates a new Scanner with default options.
@@ -103,22 +93,11 @@ func NewScannerWithOptions(opts *ScannerOptions) *Scanner {
 		fs = afero.NewOsFs()
 	}
 
-	s := &Scanner{
+	return &Scanner{
 		files:   make([]*FileEntry, 0),
 		options: opts,
 		fs:      fs,
 	}
-
-	if opts.OutputPath != "" {
-		// If the output file cannot be stat'd, normally because it does
-		// not exist yet, there is nothing to leave out.
-		info, err := s.fs.Stat(opts.OutputPath)
-		if err == nil {
-			s.outputInfo = info
-		}
-	}
-
-	return s
 }
 
 // EnumerateFile adds a single file to the scanner, calling stat() to get metadata.
@@ -456,11 +435,6 @@ func (s *Scanner) enumerateFileWithInfo(
 		info = realInfo
 	}
 
-	// The manifest being written is not one of the files it lists.
-	if s.outputInfo != nil && os.SameFile(info, s.outputInfo) {
-		return nil
-	}
-
 	entry := &FileEntry{
 		Path:    RelFilePath(cleanPath),
 		AbsPath: AbsFilePath(absPath),