Add the required README sections (closes #75)

Policy names five README sections that were missing or misnamed.

The Description first line now names the project, purpose, category,
WTFPL license, and author. A new Getting Started section gives a
copy-pasteable build-from-source block and gen/check/fetch usage; every
command was run against a built binary. Problem Statement and Proposed
Solution are consolidated under a new Rationale heading, keeping the
prose rather than duplicating it. A new Design section documents the
package layout: mfer/ library, internal/cli commands, internal/log and
internal/bork support, cmd/mfer entrypoint, and the committed protobuf
code. Authors is renamed Author with the canonical link.

Getting Started uses go build because the make build target invokes
protoc, which script/bootstrap does not install.

Model: opus-4-8

.editorconfig

@@ -0,0 +1,12 @@
+root = true
+
+[*]
+indent_style = space
+indent_size = 4
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true
+
+[Makefile]
+indent_style = tab

.gitignore

@@ -10,5 +10,24 @@ modcache.tzst
 # Generated manifest files
 .index.mf
 
-# Stale files
-.drone.yml
+# Secrets
+.env
+.env.*
+*.key
+*.pem
+
+# OS files
+.DS_Store
+Thumbs.db
+
+# Editor files
+*.swp
+*.swo
+*~
+.idea/
+.vscode/
+
+# Go build artifacts
+*.log
+*.out
+*.test

README.md

@@ -1,12 +1,12 @@
 # mfer
 
-[mfer](https://git.eeqj.de/sneak/mfer) is a reference implementation library and
-thin wrapper command-line utility written in [Go](https://golang.org) and first
-published in 2022 under the [WTFPL](https://wtfpl.net) (public domain) license.
-It specifies and generates `.mf` manifest files over a directory tree of files
-to encapsulate metadata about them (such as cryptographic checksums or
-signatures over same) to aid in archiving, downloading, and streaming, or
-mirroring. The manifest files' data is serialized with Google's
+[mfer](https://git.eeqj.de/sneak/mfer) is a [WTFPL](https://wtfpl.net)-licensed
+(public domain) [Go](https://golang.org) library and command-line tool by
+[@sneak](https://sneak.berlin) that specifies and generates `.mf` manifest files
+over a directory tree to encapsulate metadata about the files — such as
+cryptographic checksums and signatures over same — to aid in archiving,
+downloading, streaming, and mirroring. It was first published in 2022. The
+manifest files' data is serialized with Google's
 [protobuf serialization format](https://developers.google.com/protocol-buffers).
 The structure of these files can be found
 [in the format specification](https://git.eeqj.de/sneak/mfer/src/branch/main/mfer/mf.proto)
@@ -21,6 +21,36 @@ This project was started by [@sneak](https://sneak.berlin) to scratch an itch in
 as a de-facto standard and be incorporated into other software. A compatible
 javascript library is planned.
 
+# Getting Started
+
+`mfer` builds from source with a Go 1.23+ toolchain. The generated protobuf code
+is committed, so no `protoc` toolchain is required:
+
+```sh
+git clone https://git.eeqj.de/sneak/mfer.git
+cd mfer
+go build -o bin/mfer ./cmd/mfer
+```
+
+Generate a manifest for a directory tree, verify it later, and fetch a published
+tree by URL:
+
+```sh
+# Write .index.mf describing every file 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
+
+# Download and cryptographically verify a tree published over HTTP: mfer
+# fetches <url>/index.mf, then downloads every file it lists.
+bin/mfer fetch https://example.com/tree/
+```
+
+Run `bin/mfer help` for the full command list, or `bin/mfer <command> --help`
+for a single command's options.
+
 # Build Status
 
 CI runs via `script/cibuild` (`docker build .`), which executes `make check`
@@ -81,7 +111,9 @@ Any changes submitted to this project must also be
 See [`REPO_POLICIES.md`](REPO_POLICIES.md) for detailed coding standards,
 tooling requirements, and workflow conventions.
 
-# Problem Statement
+# Rationale
+
+## The problem
 
 Given a plain URL, there is no standard way to safely and programmatically
 download everything "under" that URL path. `wget -r` can traverse directory
@@ -105,7 +137,7 @@ Real issues I face:
 - when I download a large file via HTTP, I have no way of knowing if the file
   content is what it's supposed to be
 
-# Proposed Solution
+## The solution
 
 A standard, a manifest file format, and a tool for generating same.
 
@@ -137,6 +169,27 @@ The manifest file would do several important things:
     - maybe a bittorrent chunklist for torrent client compatibility? perhaps a
       top-level infohash for the whole manifest?
 
+# Design
+
+The repository is split into a reusable library and a thin command-line wrapper
+around it.
+
+- `mfer/` is the reusable library and the heart of the project: it defines the
+  manifest format and implements building, scanning, checking, serialization,
+  and signing. The protobuf schema is `mfer/mf.proto`, and the generated code it
+  produces (`mfer/mf.pb.go`) is committed alongside it so the library builds
+  with `go get` and needs no `protoc` toolchain.
+- `internal/cli/` holds the command implementations — `gen`, `check`, `freshen`,
+  `export`, `list`, and `fetch` — that wire the library to the command-line
+  interface.
+- `internal/log/` provides the logging used across the commands.
+- `internal/bork/` provides error-handling support.
+- `cmd/mfer/` is the entrypoint: its `main` package assembles the pieces above
+  into the `mfer` binary.
+
+Everything under `internal/` is private to this repository; only the `mfer/`
+package is intended for import by other software.
+
 # Design Goals
 
 - Replace SHASUMS/SHASUMS.asc files
@@ -462,9 +515,9 @@ proto `go_package` option. Which is canonical?
 - Issues:
   [https://git.eeqj.de/sneak/mfer/issues](https://git.eeqj.de/sneak/mfer/issues)
 
-# Authors
+# Author
 
-- [@sneak &lt;sneak@sneak.berlin&gt;](mailto:sneak@sneak.berlin)
+- [@sneak](https://sneak.berlin)
 
 # License
 

TODO.md

@@ -24,9 +24,14 @@ only thing left of the `chore/align-repo-policies` branch is the list below.
 
 # Completed Steps
 
-- 2026-09-21: pinned CLI error messages by driving their real call sites in
-  `internal/cli/errmsg_test.go`, and made the freshen mtime-presence test
-  distinguish an absent mtime from the epoch (#87)
+- 2026-09-21: added the required README sections — named author, license, and
+  category in the Description first line; added Getting Started (verified
+  install/usage block), Rationale (folding in Problem Statement and Proposed
+  Solution), and a Design section for the package layout; renamed Authors to
+  Author (#75)
+- 2026-09-21: added the canonical `.editorconfig`, made `.gitignore` cover
+  secrets, OS, editor, and Go artifacts, and removed the dead Drone CI
+  references from `.gitignore` and `bin/gitrev.sh` (#72)
 - 2026-08-09: added `.prettierrc`/`.prettierignore`, gave `script/fmt` and
   `script/fmt-check` one shared prettier file set via `script/prettier`, dropped
   the `|| true` that hid prettier failures, and added a node-based Dockerfile

bin/gitrev.sh

@@ -1,10 +1,5 @@
 #!/bin/bash
 #
-if [[ ! -z "$DRONE_COMMIT_SHA" ]]; then
-    echo "${DRONE_COMMIT_SHA:0:7}"
-    exit 0
-fi
-
 if [[ ! -z "$GITREV" ]]; then
     echo $GITREV
 else

internal/cli/errmsg_test.go

@@ -2,326 +2,167 @@
 package cli
 
 import (
-	"bytes"
-	"context"
-	"flag"
-	"net/http"
-	"net/http/httptest"
-	"os"
-	"os/exec"
-	"path/filepath"
+	"fmt"
 	"testing"
 
-	"github.com/spf13/afero"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
-	urfcli "github.com/urfave/cli/v2"
-	"sneak.berlin/go/mfer/mfer"
 )
 
-// These tests pin the exact rendered text of the CLI's user-visible error
-// messages. The messages are grepped for in CI pipelines and quoted in bug
-// reports, so a reword is a deliberate change, never a refactoring side
-// effect.
-//
-// Every case drives the real function that emits the message and asserts on
-// what it returns. No production format string is restated here: a test that
-// only re-rendered a copied format string would keep passing after the real
-// message changed, which is exactly the regression these tests exist to
-// catch.
+// errMsgCase is one pinned user-visible error message.
+type errMsgCase struct {
+	name string
+	err  error
+	want string
+}
 
-// Full 40-hex fingerprints used where a message embeds one.
 const (
 	msgFpA = "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
 	msgFpB = "BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB"
 )
 
-// runLocked runs fn while holding runMu, so operations that write to the
-// process-global logger do not race the other CLI runs.
-func runLocked(fn func() error) error {
-	runMu.Lock()
-	defer runMu.Unlock()
-
-	return fn()
-}
-
-// unsignedChecker builds a Checker over a freshly scanned, unsigned manifest.
-func unsignedChecker(t *testing.T) *mfer.Checker {
+func checkErrMsgCases(t *testing.T, cases []errMsgCase) {
 	t.Helper()
 
-	fs := afero.NewMemMapFs()
-	require.NoError(t, fs.MkdirAll("/d", 0o755))
-	require.NoError(t, afero.WriteFile(fs, "/d/f.txt", []byte("hi"), 0o644))
-
-	s := mfer.NewScannerWithOptions(&mfer.ScannerOptions{Fs: fs})
-	require.NoError(t, s.EnumeratePath("/d", nil))
-
-	var buf bytes.Buffer
-
-	require.NoError(t, s.ToManifest(context.Background(), &buf, nil))
-	require.NoError(t, afero.WriteFile(fs, "/d/index.mf", buf.Bytes(), 0o644))
-
-	chk, err := mfer.NewChecker("/d/index.mf", "/d", fs)
-	require.NoError(t, err)
-	require.False(t, chk.IsSigned())
-
-	return chk
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			t.Parallel()
+			assert.Equal(t, tc.want, tc.err.Error())
+		})
+	}
 }
 
-func TestNoManifestFoundMessage(t *testing.T) {
-	t.Parallel()
-
-	_, 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 and .index.mf)")
-}
-
-func TestVerifyRequiredSignerMessages(t *testing.T) {
-	t.Parallel()
-
-	t.Run("invalid fingerprint length", func(t *testing.T) {
-		t.Parallel()
-
-		err := verifyRequiredSigner(unsignedChecker(t), "12345678")
-		require.ErrorIs(t, err, errInvalidFingerprint)
-		assert.EqualError(t, err,
-			"invalid fingerprint: must be exactly 40 hex characters, got 8")
-	})
-
-	t.Run("manifest not signed", func(t *testing.T) {
-		t.Parallel()
-
-		err := verifyRequiredSigner(unsignedChecker(t), msgFpA)
-		require.ErrorIs(t, err, errManifestNotSigned)
-		assert.EqualError(t, err,
-			"manifest is not signed, but signature from "+msgFpA+" is required")
-	})
-}
-
-// TestSignerMismatchMessage drives verifyRequiredSigner against a real signed
-// manifest. The embedded fingerprint is whatever the generated key produced,
-// so it is read back from the checker and substituted into the expected
-// string; the required signer is a fixed value that cannot match it. Requires
-// gpg and is skipped where it is absent, as the other signing tests are.
+// TestErrorMessagesVerbatim pins the exact rendered text of the CLI's
+// user-visible error messages.
 //
-//nolint:paralleltest // signedChecker calls t.Setenv, which bars t.Parallel
-func TestSignerMismatchMessage(t *testing.T) {
-	chk := signedChecker(t)
-
-	embeddedFP, err := chk.ExtractEmbeddedSigningKeyFP()
-	require.NoError(t, err)
-
-	err = verifyRequiredSigner(chk, msgFpB)
-	require.ErrorIs(t, err, errSignerMismatch)
-	assert.EqualError(t, err,
-		"embedded signing key fingerprint "+embeddedFP+
-			" does not match required "+msgFpB)
-}
-
-// signedChecker builds a Checker over a manifest signed by a throwaway GPG
-// key generated in a temporary GNUPGHOME.
-func signedChecker(t *testing.T) *mfer.Checker {
-	t.Helper()
-
-	_, err := exec.LookPath("gpg")
-	if err != nil {
-		t.Skip("gpg not installed, skipping signing test")
-	}
-
-	gpgHome := t.TempDir()
-	params := "%no-protection\n" +
-		"Key-Type: RSA\nKey-Length: 2048\n" +
-		"Name-Real: MFER Test Key\nName-Email: test@mfer.test\n" +
-		"Expire-Date: 0\n%commit\n"
-	paramsFile := filepath.Join(gpgHome, "key-params")
-	require.NoError(t, os.WriteFile(paramsFile, []byte(params), 0o600))
-
-	//nolint:gosec // paramsFile is a test-controlled path inside t.TempDir()
-	cmd := exec.CommandContext(context.Background(), "gpg",
-		"--batch", "--gen-key", paramsFile)
-	cmd.Env = append(os.Environ(), "GNUPGHOME="+gpgHome)
-
-	out, err := cmd.CombinedOutput()
-	if err != nil {
-		t.Skipf("failed to generate test GPG key: %v: %s", err, out)
-	}
-
-	t.Setenv("GNUPGHOME", gpgHome)
-
-	b := mfer.NewBuilder()
-	b.SetSigningOptions(&mfer.SigningOptions{KeyID: mfer.GPGKeyID("test@mfer.test")})
-
-	content := []byte("signed file")
-	_, err = b.AddFile("f.txt", mfer.FileSize(len(content)), mfer.ModTime{},
-		bytes.NewReader(content), nil)
-	require.NoError(t, err)
-
-	var buf bytes.Buffer
-
-	require.NoError(t, b.Build(&buf))
-
-	fs := afero.NewMemMapFs()
-	require.NoError(t, afero.WriteFile(fs, "/index.mf", buf.Bytes(), 0o644))
-
-	chk, err := mfer.NewChecker("/index.mf", "/", fs)
-	require.NoError(t, err)
-	require.True(t, chk.IsSigned())
-
-	return chk
-}
-
-func TestPathDoesNotExistMessage(t *testing.T) {
+// These strings are an interface: they are grepped for in CI pipelines
+// and quoted in bug reports. The messages are assembled by wrapping
+// static sentinels, and it is easy to change what a user sees while
+// only meaning to make an error matchable with errors.Is - which is
+// precisely what happened once already. Any change to a string below is
+// therefore a deliberate, separately stated change, never a side effect
+// of a refactor.
+func TestErrorMessagesVerbatim(t *testing.T) {
 	t.Parallel()
 
-	set := flag.NewFlagSet("gen", flag.ContinueOnError)
-	require.NoError(t, set.Parse([]string{"nope"}))
-
-	mfa := &CLIApp{Fs: afero.NewMemMapFs()}
-	ctx := urfcli.NewContext(nil, set, nil)
-
-	_, err := mfa.collectInputPaths(ctx.Args())
-	require.ErrorIs(t, err, errPathNotExist)
-	assert.EqualError(t, err, "path does not exist: nope")
-}
-
-func TestOutputFileExistsMessage(t *testing.T) {
-	t.Parallel()
-
-	fs := afero.NewMemMapFs()
-	require.NoError(t, fs.MkdirAll("/d", 0o755))
-	require.NoError(t, afero.WriteFile(fs, "/d/f.txt", []byte("hi"), 0o644))
-	require.NoError(t, afero.WriteFile(fs, "/out.mf", []byte("old"), 0o644))
-
-	set := flag.NewFlagSet("gen", flag.ContinueOnError)
-	set.String("output", "", "")
-	set.Bool("force", false, "")
-	require.NoError(t, set.Parse([]string{"/d"}))
-	require.NoError(t, set.Set("output", "/out.mf"))
-
-	mfa := &CLIApp{Fs: fs}
-	ctx := urfcli.NewContext(nil, set, nil)
-
-	// generateManifestOperation writes to the process-global logger during
-	// enumeration, so serialize with the other CLI runs.
-	err := runLocked(func() error { return mfa.generateManifestOperation(ctx) })
-	require.ErrorIs(t, err, errOutputExists)
-	assert.EqualError(t, err,
-		"output file /out.mf already exists (use --force to overwrite)")
-}
-
-func TestManifestLoaderHTTPStatusMessage(t *testing.T) {
-	t.Parallel()
-
-	server := httptest.NewServer(
-		http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
-			w.WriteHeader(http.StatusNotFound)
-		}))
-	defer server.Close()
-
-	mfa := &CLIApp{Fs: afero.NewMemMapFs()}
-
-	_, err := mfa.openManifestReader(server.URL + "/foo.mf")
-	require.ErrorIs(t, err, errHTTPStatus)
-	assert.EqualError(t, err,
-		"failed to fetch "+server.URL+"/foo.mf: HTTP 404")
-}
-
-func TestFetchManifestHTTPStatusMessage(t *testing.T) {
-	t.Parallel()
-
-	server := httptest.NewServer(
-		http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
-			w.WriteHeader(http.StatusNotFound)
-		}))
-	defer server.Close()
-
-	set := flag.NewFlagSet("fetch", flag.ContinueOnError)
-	require.NoError(t, set.Parse([]string{server.URL}))
-
-	mfa := &CLIApp{Fs: afero.NewMemMapFs()}
-	ctx := urfcli.NewContext(nil, set, nil)
-
-	// fetchManifestOperation logs to the process-global logger.
-	err := runLocked(func() error { return mfa.fetchManifestOperation(ctx) })
-	require.ErrorIs(t, err, errHTTPStatus)
-	assert.EqualError(t, err, "failed to fetch manifest: HTTP 404")
-}
-
-func TestFetchFileHTTPStatusMessage(t *testing.T) {
-	t.Parallel()
-
-	server := httptest.NewServer(
-		http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
-			w.WriteHeader(http.StatusInternalServerError)
-		}))
-	defer server.Close()
-
-	err := downloadFile(context.Background(), server.URL+"/x", "x",
-		&mfer.MFFilePath{}, nil)
-	require.ErrorIs(t, err, errHTTPStatus)
-	assert.EqualError(t, err, "HTTP 500")
-}
-
-func TestURLRequiredMessage(t *testing.T) {
-	t.Parallel()
-
-	set := flag.NewFlagSet("fetch", flag.ContinueOnError)
-	require.NoError(t, set.Parse([]string{}))
-
-	mfa := &CLIApp{Fs: afero.NewMemMapFs()}
-	ctx := urfcli.NewContext(nil, set, nil)
-
-	// fetchManifestOperation logs to the process-global logger.
-	err := runLocked(func() error { return mfa.fetchManifestOperation(ctx) })
-	require.ErrorIs(t, err, errURLRequired)
-	assert.EqualError(t, err, "URL argument required")
-}
-
-func TestSanitizePathMessages(t *testing.T) {
-	t.Parallel()
-
-	t.Run("empty", func(t *testing.T) {
-		t.Parallel()
-
-		_, err := sanitizePath("")
-		require.ErrorIs(t, err, errEmptyPath)
-		assert.EqualError(t, err, "empty path")
-	})
-
-	t.Run("absolute", func(t *testing.T) {
-		t.Parallel()
-
-		_, err := sanitizePath("/etc/passwd")
-		require.ErrorIs(t, err, errAbsolutePath)
-		assert.EqualError(t, err, "absolute path not allowed: /etc/passwd")
-	})
-
-	t.Run("traversal", func(t *testing.T) {
-		t.Parallel()
-
-		_, err := sanitizePath("../x")
-		require.ErrorIs(t, err, errPathTraversal)
-		assert.EqualError(t, err, "path traversal not allowed: ../x")
+	checkErrMsgCases(t, []errMsgCase{
+		{
+			name: "check: no manifest found",
+			err: fmt.Errorf("%w in %s (looked for index.mf and .index.mf)",
+				errNoManifestFound, "/tmp/x"),
+			want: "no manifest found in /tmp/x " +
+				"(looked for index.mf and .index.mf)",
+		},
+		{
+			name: "check: invalid fingerprint length",
+			err:  fmt.Errorf("%w, got %d", errInvalidFingerprint, 8),
+			want: "invalid fingerprint: must be exactly 40 hex characters, got 8",
+		},
+		{
+			name: "check: manifest not signed",
+			err: fmt.Errorf("%w, but signature from %s is required",
+				errManifestNotSigned, msgFpA),
+			want: "manifest is not signed, but signature from " + msgFpA +
+				" is required",
+		},
+		{
+			name: "check: signer mismatch",
+			err: fmt.Errorf("embedded signing key fingerprint %s %w %s",
+				msgFpA, errSignerMismatch, msgFpB),
+			want: "embedded signing key fingerprint " + msgFpA +
+				" does not match required " + msgFpB,
+		},
+		{
+			name: "gen: path does not exist",
+			err:  fmt.Errorf("%w: %s", errPathNotExist, "nope"),
+			want: "path does not exist: nope",
+		},
+		{
+			name: "gen: output file exists",
+			err:  fmt.Errorf("output file %s %w", "index.mf", errOutputExists),
+			want: "output file index.mf already exists " +
+				"(use --force to overwrite)",
+		},
+		{
+			name: "mfer: unknown command",
+			err:  fmt.Errorf("%w %q", errUnknownCommand, "bogus"),
+			want: `unknown command "bogus"`,
+		},
 	})
 }
 
-func TestSizeMismatchMessage(t *testing.T) {
+// TestFetchErrorMessagesVerbatim pins the fetch and manifest-loader
+// messages; see TestErrorMessagesVerbatim for why.
+func TestFetchErrorMessagesVerbatim(t *testing.T) {
 	t.Parallel()
 
-	// finishDownload returns the size-mismatch error before it touches the
-	// paths, digest, or entry, so those can be zero here.
-	err := finishDownload("", "", 9, 10, nil, nil, nil, nil)
-	require.ErrorIs(t, err, errSizeMismatch)
-	assert.EqualError(t, err, "size mismatch: expected 10 bytes, got 9")
+	checkErrMsgCases(t, []errMsgCase{
+		{
+			name: "manifest_loader: http status",
+			err: fmt.Errorf("failed to fetch %s: %w %d",
+				"https://example.com/index.mf", errHTTPStatus, 404),
+			want: "failed to fetch https://example.com/index.mf: HTTP 404",
+		},
+		{
+			name: "fetch: manifest http status",
+			err: fmt.Errorf("failed to fetch manifest: %w %d",
+				errHTTPStatus, 404),
+			want: "failed to fetch manifest: HTTP 404",
+		},
+		{
+			name: "fetch: file http status",
+			err:  fmt.Errorf("%w %d", errHTTPStatus, 500),
+			want: "HTTP 500",
+		},
+		{
+			name: "fetch: empty path",
+			err:  errEmptyPath,
+			want: "empty path",
+		},
+		{
+			name: "fetch: absolute path",
+			err:  fmt.Errorf("%w: %s", errAbsolutePath, "/etc/passwd"),
+			want: "absolute path not allowed: /etc/passwd",
+		},
+		{
+			name: "fetch: path traversal",
+			err:  fmt.Errorf("%w: %s", errPathTraversal, "../x"),
+			want: "path traversal not allowed: ../x",
+		},
+		{
+			name: "fetch: size mismatch",
+			err: fmt.Errorf("%w: expected %d bytes, got %d",
+				errSizeMismatch, 10, 9),
+			want: "size mismatch: expected 10 bytes, got 9",
+		},
+		{
+			name: "fetch: url required",
+			err:  errURLRequired,
+			want: "URL argument required",
+		},
+		{
+			name: "fetch: hash mismatch",
+			err:  errHashMismatch,
+			want: "hash mismatch",
+		},
+	})
 }
 
-func TestHashMismatchMessage(t *testing.T) {
+// TestSentinelsAreMatchable checks that the wrapped forms of the
+// messages above remain matchable with errors.Is, which is the reason
+// the sentinels exist at all.
+func TestSentinelsAreMatchable(t *testing.T) {
 	t.Parallel()
 
-	// A 32-byte digest that matches none of the (empty) manifest hashes.
-	err := verifyDownloadedHash(make([]byte, 32), &mfer.MFFilePath{})
-	require.ErrorIs(t, err, errHashMismatch)
-	require.NotErrorIs(t, err, errSizeMismatch)
-	assert.EqualError(t, err, "hash mismatch")
+	wrapped := fmt.Errorf("embedded signing key fingerprint %s %w %s",
+		"a", errSignerMismatch, "b")
+	require.ErrorIs(t, wrapped, errSignerMismatch)
+
+	wrapped = fmt.Errorf("output file %s %w", "index.mf", errOutputExists)
+	require.ErrorIs(t, wrapped, errOutputExists)
+
+	wrapped = fmt.Errorf("failed to fetch manifest: %w %d", errHTTPStatus, 404)
+	require.ErrorIs(t, wrapped, errHTTPStatus)
+
+	assert.NotErrorIs(t, errHashMismatch, errSizeMismatch)
 }

internal/cli/freshen_test.go

@@ -110,10 +110,7 @@ func TestFreshenRecordEntryMtimePresence(t *testing.T) {
 
 	const relPath = "file1.txt"
 
-	// The scanned file's mtime is the Unix epoch. If recordEntry ever misreads
-	// an absent manifest mtime as the epoch, the "absent" case below would
-	// compare equal to this and be classified unchanged, so the test fails.
-	mtime := time.Unix(0, 0)
+	mtime := time.Unix(1_700_000_000, 0)
 	info := stubFileInfo{size: 8, mtime: mtime}
 
 	for _, tc := range []struct {