Rewrite remembering in Go

The shell pipeline (sed | sort | tee | awk | sort | cut | "$@"
plus the cut | uniq | awk profile rewrite) becomes a single static
binary with the same observable behaviour, pinned by the original
ranking.sh, signals.sh and cli-opts.sh suites, now aimed at
remembering.bin:

- the profile keeps the exact on-disk format, COUNT profile TEXT,
  byte-sorted with new picks appended at 1 and offered-but-never-
  picked entries persisted at 0;
- the menu stays count-descending with byte-order ties, stdin
  alone defines what is offered, and duplicate profile lines sum
  for ranking but collapse to the highest count on rewrite, as
  sort | uniq -f1 did;
- the wrapped command's exit status is forwarded as-is (128+sig
  for signal deaths), its stderr passes through, and an empty pick
  learns nothing;
- the profile rewrite stays atomic via .tmp plus rename.

Per the house CLI conventions, -h/-V/--help/--version are gone
(the manpage is the documentation; bad options print the usage on
stderr and exit 2), and getopts-style attached option arguments
(-pNAME) are not accepted any more --- no script in the wild used
them.

The project layout follows rot: raw go tool compile/link Makefile,
mkdeps.sh-generated deps.mk, white-box unit suite, fuzz target
over the profile parse/serialize roundtrip, functional pick
roundtrip, a 1M-line ranking benchmark, and a single English
asciidoc manpage absorbing the old .5 page; the po4a/aux release
machinery goes away.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

1 files changed, 129 insertions, 0 deletions

diff --git a/tests/functional/pick-roundtrip/remembering.go b/tests/functional/pick-roundtrip/remembering.go
new file mode 100644
index 0000000..e2d54da
--- /dev/null
+++ b/tests/functional/pick-roundtrip/remembering.go
@@ -0,0 +1,129 @@
+package remembering
+
+import (
+	"fmt"
+	"os"
+	"reflect"
+	"strings"
+)
+
+
+
+func showColour() bool {
+	return os.Getenv("NO_COLOUR") == ""
+}
+
+func testing(message string, body func()) {
+	if showColour() {
+		fmt.Fprintf(
+			os.Stderr,
+			"\033[0;33mtesting\033[0m: %s... ",
+			message,
+		)
+		body()
+		fmt.Fprintf(os.Stderr, "\033[0;32mOK\033[0m.\n")
+	} else {
+		fmt.Fprintf(os.Stderr, "testing: %s... ", message)
+		body()
+		fmt.Fprintf(os.Stderr, "OK.\n")
+	}
+}
+
+func assertEq(given any, expected any) {
+	if !reflect.DeepEqual(given, expected) {
+		if showColour() {
+			fmt.Fprintf(os.Stderr, "\033[0;31mERR\033[0m.\n")
+		} else {
+			fmt.Fprintf(os.Stderr, "ERR.\n")
+		}
+		fmt.Fprintf(os.Stderr, "given != expected\n")
+		fmt.Fprintf(os.Stderr, "given:    %#v\n", given)
+		fmt.Fprintf(os.Stderr, "expected: %#v\n", expected)
+		os.Exit(1)
+	}
+}
+
+
+
+func pick(menu string, command ...string) (int, string, string) {
+	out := strings.Builder{}
+	errW := strings.Builder{}
+	rc := run(envT{
+		allArgs: append(
+			[]string{"remembering", "-p", "func", "--"},
+			command...,
+		),
+		in:  strings.NewReader(menu),
+		out: &out,
+		err: &errW,
+	})
+	return rc, out.String(), errW.String()
+}
+
+func profileBytes() string {
+	path, err := profilePath("func")
+	if err != nil {
+		panic(err)
+	}
+	data, err := os.ReadFile(path)
+	if err != nil {
+		panic(err)
+	}
+	return string(data)
+}
+
+
+
+func MainTest() {
+	testing("a session of picks shapes the ranking", func() {
+		tmp, err := os.MkdirTemp(
+			"", "remembering-functional-",
+		)
+		assertEq(err, nil)
+		defer os.RemoveAll(tmp)
+		saved := os.Getenv("XDG_DATA_HOME")
+		os.Setenv("XDG_DATA_HOME", tmp)
+		defer os.Setenv("XDG_DATA_HOME", saved)
+
+		menu := "a\nb\nc\nd\ne\n"
+
+		rc, out, errW := pick(menu, "grep", "-F", "c")
+		assertEq(rc, 0)
+		assertEq(out, "c\n")
+		assertEq(errW, "")
+		assertEq(
+			profileBytes(),
+			"0 profile a\n"+
+				"0 profile b\n"+
+				"1 profile c\n"+
+				"0 profile d\n"+
+				"0 profile e\n",
+		)
+
+		// the learnt pick now ranks first
+		rc, out, errW = pick(menu, "head", "-n1")
+		assertEq(rc, 0)
+		assertEq(out, "c\n")
+		assertEq(errW, "")
+		assertEq(
+			profileBytes(),
+			"0 profile a\n"+
+				"0 profile b\n"+
+				"2 profile c\n"+
+				"0 profile d\n"+
+				"0 profile e\n",
+		)
+
+		// a cancelled menu forwards the status and
+		// learns nothing
+		rc, out, _ = pick(menu, "sh", "-c", "exit 3")
+		assertEq(rc, 3)
+		assertEq(out, "")
+		assertEq(
+			strings.Contains(
+				profileBytes(), "2 profile c",
+			),
+			true,
+		)
+	})
+}