Default the manifest to index.mf and keep it out of its own listing (closes #100)

mfer gen now writes index.mf instead of .index.mf, the name fetch
requests and the README calls the standard filename. Given a
directory, check, freshen, list and export look only for index.mf;
.index.mf is no longer recognized. Because index.mf is not hidden, gen
and freshen now leave out of their own listing both the manifest they
write and a temp file an interrupted run left beside it, by file
identity (os.SameFile), so each is recognized however its path is
spelled, while an ordinary file of the same name elsewhere in the tree
is still listed.

Model: opus-5-5

internal/cli/freshen.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"io"
 	"io/fs"
+	"os"
 	"path/filepath"
 	"time"
 
@@ -56,7 +57,8 @@ type freshenEntry struct {
 type freshenScanner struct {
 	fs              afero.Fs
 	absBase         string
-	manifestBase    string
+	manifestInfo    fs.FileInfo // the manifest being freshened
+	tmpInfo         fs.FileInfo // its leftover temp file; nil when there is none
 	includeDotfiles bool
 	followSymlinks  bool
 	showProgress    bool
@@ -156,11 +158,6 @@ 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() {
@@ -185,6 +182,13 @@ func (s *freshenScanner) walk(path string, info fs.FileInfo, walkErr error) erro
 		info = realInfo
 	}
 
+	// Skip the manifest file itself and a temp file left beside it by an
+	// interrupted run, however their paths are spelled; gen leaves out its
+	// output file the same way. os.SameFile never matches a nil FileInfo.
+	if os.SameFile(info, s.manifestInfo) || os.SameFile(info, s.tmpInfo) {
+		return nil
+	}
+
 	s.scanCount++
 
 	// Check against existing manifest
@@ -364,17 +368,33 @@ 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)
+	}
+
+	// The temp file writeFreshenedManifest writes, if an interrupted run
+	// left one. One that cannot be stat'd, normally because it does not
+	// exist, needs no leaving out.
+	var tmpInfo fs.FileInfo
+
+	info, err := mfa.Fs.Stat(manifestPath + ".tmp")
+	if err == nil {
+		tmpInfo = info
+	}
+
 	scanner := &freshenScanner{
 		fs:              mfa.Fs,
 		absBase:         absBase,
-		manifestBase:    filepath.Base(manifestPath),
+		manifestInfo:    manifestInfo,
+		tmpInfo:         tmpInfo,
 		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()