package sunrise

import (
	"bytes"
	"errors"
	"os"
	"os/exec"
	"path/filepath"
	"strings"
	"testing"
)

// scriptHarness runs new.sh with bash on a PATH that holds only a symlink to
// the real git plus stub go and docker commands. The go stub answers
// `go env GOVERSION|GOBIN|GOPATH` from the harness and, for
// `go -C <dir> install ./cmd/summer`, writes a stub summer into the Go bin
// directory that records its working directory, arguments and stdin.
type scriptHarness struct {
	t      *testing.T
	bash   string
	script string
	root   string // per-case temp root
	work   string // the directory the script runs in
	tools  string // the PATH directory
	logs   string // stub call records
	gobin  string
	gopath string
	remote *fakeRemote

	goVersion   string // go env GOVERSION
	useGOBIN    bool   // go env GOBIN prints gobin; otherwise empty, GOPATH/bin is used
	gobinOnPath bool
	unsetShell  bool     // run the script with SHELL unset instead of the empty default
	env         []string // extra environment
}

type scriptResult struct {
	code           int
	stdout, stderr string
}

// stdinProbe is piped into every run: the script must never let a child
// read it.
const stdinProbe = "SHOULD-NOT-BE-READ\n"

// fwModule is the framework module path the script requires.
const fwModule = "git.golem15.com/golem15/summercms"

// gitTestEnv isolates git from the user's configuration and supplies an
// identity for the commits the harness itself makes.
func gitTestEnv(home string) []string {
	return []string{
		"HOME=" + home,
		"XDG_CONFIG_HOME=" + filepath.Join(home, ".config"),
		"GIT_CONFIG_NOSYSTEM=1",
		"GIT_CONFIG_GLOBAL=" + os.DevNull,
		// Detached auto maintenance would write into temp repos during cleanup.
		"GIT_CONFIG_COUNT=2",
		"GIT_CONFIG_KEY_0=maintenance.auto", "GIT_CONFIG_VALUE_0=false",
		"GIT_CONFIG_KEY_1=gc.auto", "GIT_CONFIG_VALUE_1=0",
		"GIT_AUTHOR_NAME=Test", "GIT_AUTHOR_EMAIL=test@example.com",
		"GIT_COMMITTER_NAME=Test", "GIT_COMMITTER_EMAIL=test@example.com",
		"LC_ALL=C",
	}
}

// fakeRemote is a bare framework repository fed from a work clone.
type fakeRemote struct {
	t    *testing.T
	env  []string
	bare string
	src  string
	n    int
	tags map[string]string // tag -> commit
}

func (r *fakeRemote) git(dir string, args ...string) string {
	r.t.Helper()
	cmd := exec.Command("git", args...)
	cmd.Dir = dir
	cmd.Env = append(os.Environ()[:0:0], append([]string{"PATH=" + os.Getenv("PATH")}, r.env...)...)
	out, err := cmd.CombinedOutput()
	if err != nil {
		r.t.Fatalf("git %v in %s: %v\n%s", args, dir, err, out)
	}
	return strings.TrimSpace(string(out))
}

// commit adds a commit on main and returns its hash.
func (r *fakeRemote) commit() string {
	r.t.Helper()
	r.n++
	if err := os.WriteFile(filepath.Join(r.src, "VERSION"), []byte(strings.Repeat("x", r.n)+"\n"), 0o644); err != nil {
		r.t.Fatal(err)
	}
	r.git(r.src, "add", "-A")
	r.git(r.src, "commit", "-q", "-m", "commit")
	r.git(r.src, "push", "-q", "origin", "main")
	return r.git(r.src, "rev-parse", "HEAD")
}

// tag commits and tags the new commit, then pushes the tag.
func (r *fakeRemote) tag(tag string) string {
	r.t.Helper()
	c := r.commit()
	r.git(r.src, "tag", tag)
	r.git(r.src, "push", "-q", "origin", "refs/tags/"+tag)
	r.tags[tag] = c
	return c
}

// moveTag recreates tag on a new commit upstream.
func (r *fakeRemote) moveTag(tag string) string {
	r.t.Helper()
	c := r.commit()
	r.git(r.src, "tag", "-f", tag)
	r.git(r.src, "push", "-q", "--force", "origin", "refs/tags/"+tag)
	r.tags[tag] = c
	return c
}

func newFakeRemote(t *testing.T, root string, env []string) *fakeRemote {
	t.Helper()
	r := &fakeRemote{t: t, env: env, bare: filepath.Join(root, "remote.git"), src: filepath.Join(root, "remote-src"), tags: map[string]string{}}
	r.git(root, "init", "-q", "--bare", "--initial-branch=main", r.bare)
	r.git(root, "init", "-q", "--initial-branch=main", r.src)
	if err := os.WriteFile(filepath.Join(r.src, "go.mod"), []byte("module "+fwModule+"\n\ngo 1.27.0\n"), 0o644); err != nil {
		t.Fatal(err)
	}
	r.git(r.src, "remote", "add", "origin", r.bare)
	r.git(r.src, "add", "-A")
	r.git(r.src, "commit", "-q", "-m", "init")
	r.git(r.src, "push", "-q", "origin", "main")
	r.tag("v0.1.0")
	r.tag("v0.2.0")
	r.tag("v0.10.0")
	// A pre-release newer than every release: never selected.
	r.tag("v1.0.0-rc1")
	return r
}

func newScriptHarness(t *testing.T) *scriptHarness {
	t.Helper()
	bash := lookBash(t)
	gitBin, err := exec.LookPath("git")
	if err != nil {
		t.Skip("git not installed")
	}
	gitBin, err = filepath.Abs(gitBin)
	if err != nil {
		t.Fatal(err)
	}
	chmod, err := exec.LookPath("chmod")
	if err != nil {
		t.Skip("chmod not found")
	}
	root := t.TempDir()
	h := &scriptHarness{
		t:         t,
		bash:      bash,
		root:      root,
		work:      filepath.Join(root, "work"),
		tools:     filepath.Join(root, "tools"),
		logs:      filepath.Join(root, "logs"),
		gobin:     filepath.Join(root, "gobin"),
		gopath:    filepath.Join(root, "gopath"),
		goVersion: "go1.27.0",
		useGOBIN:  true,
	}
	for _, d := range []string{h.work, h.tools, h.logs, h.gobin, filepath.Join(h.gopath, "bin"), filepath.Join(root, "home")} {
		if err := os.MkdirAll(d, 0o755); err != nil {
			t.Fatal(err)
		}
	}
	h.script = filepath.Join(root, "new.sh")
	if err := os.WriteFile(h.script, Script(), 0o644); err != nil {
		t.Fatal(err)
	}
	if err := os.Symlink(gitBin, filepath.Join(h.tools, "git")); err != nil {
		t.Fatal(err)
	}
	summerStub := "#!" + bash + `
{ printf 'cwd=%s\n' "$(pwd)"; printf 'arg=%s\n' "$@"; } >"$STUB_LOG/summer.call"
data=""
while IFS= read -r line || [[ -n $line ]]; do data+="$line"; done
printf '%s' "$data" >"$STUB_LOG/summer.stdin"
`
	goStub := "#!" + bash + `
printf '%s\n' "$*" >>"$STUB_LOG/go.calls"
case "$1 ${2:-}" in
"env GOVERSION") printf '%s\n' "$STUB_GOVERSION"; exit 0 ;;
"env GOBIN") printf '%s\n' "$STUB_GOBIN"; exit 0 ;;
"env GOPATH") printf '%s\n' "$STUB_GOPATH"; exit 0 ;;
esac
if [[ $1 == -C && $3 == install && $4 == ./cmd/summer ]]; then
	printf 'GOWORK=%s dir=%s\n' "${GOWORK-unset}" "$2" >>"$STUB_LOG/go.install"
	bin="$STUB_GOBIN"
	[[ -n $bin ]] || bin="${STUB_GOPATH%%:*}/bin"
	printf '%s' "$SUMMER_STUB" >"$bin/summer"
	'` + chmod + `' 0755 "$bin/summer"
	exit 0
fi
printf 'unexpected go %s\n' "$*" >&2
exit 3
`
	dockerStub := "#!" + bash + "\nprintf '%s\\n' \"$*\" >>\"$STUB_LOG/docker.calls\"\nexit 0\n"
	write := func(name, body string) {
		if err := os.WriteFile(filepath.Join(h.tools, name), []byte(body), 0o755); err != nil {
			t.Fatal(err)
		}
	}
	write("go", goStub)
	write("docker", dockerStub)
	h.env = append(h.env, "SUMMER_STUB="+summerStub)
	h.remote = newFakeRemote(t, root, append(gitTestEnv(filepath.Join(root, "home")), "GIT_CEILING_DIRECTORIES="+root))
	return h
}

// without removes a tool from the stub PATH.
func (h *scriptHarness) without(tool string) {
	h.t.Helper()
	if err := os.Remove(filepath.Join(h.tools, tool)); err != nil {
		h.t.Fatal(err)
	}
}

// run executes the script with args in h.work.
func (h *scriptHarness) run(args ...string) scriptResult {
	h.t.Helper()
	path := h.tools
	if h.gobinOnPath {
		path += ":" + h.gobin
	}
	gobin := ""
	if h.useGOBIN {
		gobin = h.gobin
	}
	env := append(gitTestEnv(filepath.Join(h.root, "home")),
		"PATH="+path,
		"PWD="+h.work,
		"GIT_CEILING_DIRECTORIES="+h.root,
		"SUMMERCMS_REPO="+h.remote.bare,
		"STUB_LOG="+h.logs,
		"STUB_GOVERSION="+h.goVersion,
		"STUB_GOBIN="+gobin,
		"STUB_GOPATH="+h.gopath,
		// bash fills an unset SHELL from the passwd entry, so this default
		// keeps cases independent of the developer's login shell; a case
		// sets its own SHELL through h.env, which comes later and wins.
		"SHELL=",
	)
	// The script must not depend on the harness identity: drop it.
	filtered := env[:0]
	for _, kv := range env {
		if strings.HasPrefix(kv, "GIT_AUTHOR_") || strings.HasPrefix(kv, "GIT_COMMITTER_") {
			continue
		}
		filtered = append(filtered, kv)
	}
	env = append(filtered, h.env...)
	cmd := exec.Command(h.bash, append([]string{h.script}, args...)...)
	if h.unsetShell {
		// Unset SHELL inside bash, after startup filled it, then source the
		// script ($0) with the case arguments so it runs with SHELL unset.
		cmd = exec.Command(h.bash, append([]string{"-c", `unset SHELL; . "$0" "$@"`, h.script}, args...)...)
	}
	cmd.Dir = h.work
	cmd.Env = env
	cmd.Stdin = strings.NewReader(stdinProbe)
	var stdout, stderr bytes.Buffer
	cmd.Stdout = &stdout
	cmd.Stderr = &stderr
	err := cmd.Run()
	res := scriptResult{stdout: stdout.String(), stderr: stderr.String()}
	var exitErr *exec.ExitError
	switch {
	case err == nil:
	case errors.As(err, &exitErr):
		res.code = exitErr.ExitCode()
	default:
		h.t.Fatalf("run script: %v", err)
	}
	return res
}

// mustRun runs the script and requires success.
func (h *scriptHarness) mustRun(args ...string) scriptResult {
	h.t.Helper()
	res := h.run(args...)
	if res.code != 0 {
		h.t.Fatalf("script exit %d\nstdout:\n%s\nstderr:\n%s", res.code, res.stdout, res.stderr)
	}
	return res
}

func (h *scriptHarness) checkout() string { return filepath.Join(h.work, "summercms") }

func (h *scriptHarness) head() string {
	h.t.Helper()
	return h.remote.git(h.checkout(), "rev-parse", "HEAD")
}

func (h *scriptHarness) log(name string) string {
	data, err := os.ReadFile(filepath.Join(h.logs, name))
	if err != nil {
		return ""
	}
	return string(data)
}

func (h *scriptHarness) exists(rel string) bool {
	_, err := os.Lstat(filepath.Join(h.work, rel))
	return err == nil
}

func expectCode(t *testing.T, res scriptResult, code int) {
	t.Helper()
	if res.code != code {
		t.Fatalf("exit %d, want %d\nstdout:\n%s\nstderr:\n%s", res.code, code, res.stdout, res.stderr)
	}
}

func expectContains(t *testing.T, what, got string, wants ...string) {
	t.Helper()
	for _, want := range wants {
		if !strings.Contains(got, want) {
			t.Fatalf("%s lacks %q:\n%s", what, want, got)
		}
	}
}

func expectLacks(t *testing.T, what, got string, unwanted ...string) {
	t.Helper()
	for _, u := range unwanted {
		if strings.Contains(got, u) {
			t.Fatalf("%s contains %q:\n%s", what, u, got)
		}
	}
}

// hintDir returns dir escaped the way new.sh escapes it inside the double
// quotes of the printed PATH hint: backslash, double quote and dollar for
// every shell, plus backtick and a single-quoted ! for POSIX shells.
func hintDir(dir string, fish bool) string {
	if fish {
		return strings.NewReplacer(`\`, `\\`, `"`, `\"`, `$`, `\$`).Replace(dir)
	}
	return strings.NewReplacer(`\`, `\\`, `"`, `\"`, `$`, `\$`, "`", "\\`", `!`, `"'!'"`).Replace(dir)
}

// hint is the PATH hint new.sh prints at the end of stdout.
func hint(gobin, note, line string) string {
	return "\n==> summer is installed in " + gobin + ", which is not on your PATH. Run this (" + note + "):\n" + line + "\n"
}

// exportHint and fishHint are the two hint forms for gobin.
func exportHint(gobin, note string) string {
	return hint(gobin, note, `  export PATH="`+hintDir(gobin, false)+`:$PATH"`)
}

func fishHint(gobin string) string {
	return hint(gobin, "fish_add_path also keeps it for new fish sessions", `  fish_add_path "`+hintDir(gobin, true)+`"`)
}

// expectHintSuffix asserts stdout ends with the hint.
func expectHintSuffix(t *testing.T, stdout, want string) {
	t.Helper()
	if !strings.HasSuffix(stdout, want) {
		t.Fatalf("stdout does not end with the hint\ngot:\n%q\nwant suffix:\n%q", stdout, want)
	}
}

// metaGobin creates and selects a Go bin directory whose name holds a
// space, backslash, double quote, dollar, backtick and !.
func metaGobin(t *testing.T, h *scriptHarness) {
	t.Helper()
	h.gobin = filepath.Join(h.root, "go bin\\x\"y$HOME`id`!z")
	if err := os.MkdirAll(h.gobin, 0o755); err != nil {
		t.Fatal(err)
	}
}

// expectNothingStarted asserts no clone and no go or summer call happened.
func expectNothingStarted(t *testing.T, h *scriptHarness) {
	t.Helper()
	if h.exists("summercms") {
		t.Fatal("the framework was cloned")
	}
	if c := h.log("go.calls"); c != "" {
		t.Fatalf("go was called:\n%s", c)
	}
	if c := h.log("summer.call"); c != "" {
		t.Fatalf("summer was called:\n%s", c)
	}
}

// expectRefusedUnchanged asserts a refusal with exit 1 that left HEAD at
// before and never reached go install or summer.
func expectRefusedUnchanged(t *testing.T, h *scriptHarness, res scriptResult, before string, msg string) {
	t.Helper()
	expectCode(t, res, 1)
	expectContains(t, "stderr", res.stderr, msg)
	if got := h.head(); got != before {
		t.Fatalf("HEAD moved from %s to %s", before, got)
	}
	if c := h.log("summer.call"); c != "" {
		t.Fatalf("summer was called after a refusal:\n%s", c)
	}
}

// resetLogs clears stub records between runs of one case.
func (h *scriptHarness) resetLogs() {
	h.t.Helper()
	for _, n := range []string{"go.calls", "go.install", "summer.call", "summer.stdin", "docker.calls"} {
		_ = os.Remove(filepath.Join(h.logs, n))
	}
}

func TestScriptBehavior(t *testing.T) {
	cases := []struct {
		name string
		run  func(t *testing.T, h *scriptHarness)
	}{
		{"help prints usage and exits 0", func(t *testing.T, h *scriptHarness) {
			res := h.run("--help")
			expectCode(t, res, 0)
			expectContains(t, "stdout", res.stdout, "Usage: curl -fsSL https://summercms.io/new | bash -s -- <name>", "SUMMERCMS_REF")
			expectNothingStarted(t, h)
		}},
		{"no argument is a usage error", func(t *testing.T, h *scriptHarness) {
			res := h.run()
			expectCode(t, res, 2)
			expectContains(t, "stderr", res.stderr, "Usage:")
			expectNothingStarted(t, h)
		}},
		{"two arguments are a usage error", func(t *testing.T, h *scriptHarness) {
			res := h.run("demo", "extra")
			expectCode(t, res, 2)
			expectNothingStarted(t, h)
		}},
		{"upper-case name is rejected", func(t *testing.T, h *scriptHarness) {
			res := h.run("Demo")
			expectCode(t, res, 2)
			expectContains(t, "stderr", res.stderr, "invalid application name")
			expectNothingStarted(t, h)
		}},
		{"name with shell metacharacters is rejected", func(t *testing.T, h *scriptHarness) {
			res := h.run("demo;touch pwned")
			expectCode(t, res, 2)
			if h.exists("pwned") {
				t.Fatal("the name was executed")
			}
			expectNothingStarted(t, h)
		}},
		{"existing app stops before any clone", func(t *testing.T, h *scriptHarness) {
			if err := os.Mkdir(filepath.Join(h.work, "sm-demo-app"), 0o755); err != nil {
				t.Fatal(err)
			}
			res := h.run("demo")
			expectCode(t, res, 1)
			expectContains(t, "stderr", res.stderr, "sm-demo-app already exists")
			expectNothingStarted(t, h)
		}},
		{"Go missing names go.dev/dl", func(t *testing.T, h *scriptHarness) {
			h.without("go")
			res := h.run("demo")
			expectCode(t, res, 1)
			expectContains(t, "stderr", res.stderr, "Go is not installed", "https://go.dev/dl/")
			expectNothingStarted(t, h)
		}},
		{"Go older than 1.27 is refused", func(t *testing.T, h *scriptHarness) {
			h.goVersion = "go1.26.3"
			res := h.run("demo")
			expectCode(t, res, 1)
			expectContains(t, "stderr", res.stderr, "found go1.26.3", "https://go.dev/dl/")
			if h.exists("summercms") {
				t.Fatal("cloned despite an old Go")
			}
		}},
		{"devel Go version only warns", func(t *testing.T, h *scriptHarness) {
			h.goVersion = "devel go1.28-0123456789ab"
			res := h.mustRun("demo")
			expectContains(t, "stderr", res.stderr, "warning: could not read the Go version")
			if h.log("summer.call") == "" {
				t.Fatal("summer was not called")
			}
		}},
		{"git missing is an error", func(t *testing.T, h *scriptHarness) {
			h.without("git")
			res := h.run("demo")
			expectCode(t, res, 1)
			expectContains(t, "stderr", res.stderr, "git is not installed")
			expectNothingStarted(t, h)
		}},
		{"Docker missing only warns", func(t *testing.T, h *scriptHarness) {
			h.without("docker")
			res := h.mustRun("demo")
			expectContains(t, "stderr", res.stderr, "warning: Docker is not installed")
			if h.log("summer.call") == "" {
				t.Fatal("summer was not called")
			}
		}},
		{"fresh clone at the newest release", func(t *testing.T, h *scriptHarness) {
			res := h.mustRun("demo")
			if got, want := h.head(), h.remote.tags["v0.10.0"]; got != want {
				t.Fatalf("HEAD = %s, want v0.10.0 %s (numeric order, pre-release ignored)", got, want)
			}
			cmd := exec.Command("git", "-C", h.checkout(), "symbolic-ref", "-q", "HEAD")
			if err := cmd.Run(); err == nil {
				t.Fatal("checkout is on a branch, want detached")
			}
			fw := filepath.Join(h.work, "summercms")
			call := h.log("summer.call")
			want := "cwd=" + h.work + "\narg=new\narg=demo\narg=--framework\narg=" + fw + "\n"
			if call != want {
				t.Fatalf("summer call:\n%s\nwant:\n%s", call, want)
			}
			if got := h.log("summer.stdin"); got != "" {
				t.Fatalf("summer read stdin %q", got)
			}
			if got, want := h.log("go.install"), "GOWORK=off dir="+fw+"\n"; got != want {
				t.Fatalf("go install = %q, want %q", got, want)
			}
			expectContains(t, "stdout", res.stdout, "  cd "+filepath.Join(h.work, "sm-demo-app")+"\n")
			expectContains(t, "stderr", res.stderr, "framework target: v0.10.0")
		}},
		{"SUMMERCMS_REF selects a tag", func(t *testing.T, h *scriptHarness) {
			h.env = append(h.env, "SUMMERCMS_REF=v0.2.0")
			res := h.mustRun("demo")
			if got, want := h.head(), h.remote.tags["v0.2.0"]; got != want {
				t.Fatalf("HEAD = %s, want v0.2.0 %s", got, want)
			}
			expectContains(t, "stderr", res.stderr, "framework target: v0.2.0")
		}},
		{"SUMMERCMS_REF starting with a dash is refused", func(t *testing.T, h *scriptHarness) {
			h.env = append(h.env, "SUMMERCMS_REF=--upload-pack=x")
			res := h.run("demo")
			expectCode(t, res, 1)
			expectContains(t, "stderr", res.stderr, "SUMMERCMS_REF must be a tag or commit")
			if h.log("summer.call") != "" {
				t.Fatal("summer was called")
			}
		}},
		{"re-run moves forward to a new release", func(t *testing.T, h *scriptHarness) {
			h.mustRun("demo")
			next := h.remote.tag("v0.11.0")
			h.resetLogs()
			res := h.mustRun("demo")
			if got := h.head(); got != next {
				t.Fatalf("HEAD = %s, want v0.11.0 %s", got, next)
			}
			expectContains(t, "stderr", res.stderr, "updating the framework checkout", "framework target: v0.11.0")
		}},
		{"re-run at the newest release changes nothing", func(t *testing.T, h *scriptHarness) {
			h.mustRun("demo")
			before := h.head()
			h.resetLogs()
			res := h.mustRun("demo")
			if got := h.head(); got != before {
				t.Fatalf("HEAD moved from %s to %s", before, got)
			}
			expectContains(t, "stderr", res.stderr, "already at the target")
		}},
		{"tracked change refuses and is kept", func(t *testing.T, h *scriptHarness) {
			h.mustRun("demo")
			before := h.head()
			mod := filepath.Join(h.checkout(), "go.mod")
			edited := "module " + fwModule + "\n\ngo 1.27.0\n// local edit\n"
			if err := os.WriteFile(mod, []byte(edited), 0o644); err != nil {
				t.Fatal(err)
			}
			h.resetLogs()
			res := h.run("demo")
			expectRefusedUnchanged(t, h, res, before, "uncommitted changes to tracked files")
			if got, _ := os.ReadFile(mod); string(got) != edited {
				t.Fatalf("go.mod changed: %q", got)
			}
		}},
		{"branch checkout refuses", func(t *testing.T, h *scriptHarness) {
			h.mustRun("demo")
			h.remote.git(h.checkout(), "switch", "-q", "-c", "mine")
			before := h.head()
			h.resetLogs()
			res := h.run("demo")
			expectRefusedUnchanged(t, h, res, before, "is on branch mine")
			if got := h.remote.git(h.checkout(), "symbolic-ref", "--short", "HEAD"); got != "mine" {
				t.Fatalf("branch = %s", got)
			}
		}},
		{"non-fast-forward refuses", func(t *testing.T, h *scriptHarness) {
			h.mustRun("demo")
			h.remote.git(h.checkout(), "commit", "-q", "--allow-empty", "-m", "local work")
			before := h.head()
			h.resetLogs()
			res := h.run("demo")
			expectRefusedUnchanged(t, h, res, before, "is not a fast-forward")
		}},
		{"moved upstream tag refuses", func(t *testing.T, h *scriptHarness) {
			h.mustRun("demo")
			before := h.head()
			moved := h.remote.moveTag("v0.10.0")
			h.resetLogs()
			res := h.run("demo")
			if res.code == 0 {
				t.Fatalf("script followed a moved tag\nstderr:\n%s", res.stderr)
			}
			if got := h.head(); got != before {
				t.Fatalf("HEAD moved from %s to %s", before, got)
			}
			if got := h.remote.git(h.checkout(), "rev-parse", "refs/tags/v0.10.0^{commit}"); got == moved || got != before {
				t.Fatalf("local v0.10.0 = %s, want the original %s (upstream moved to %s)", got, before, moved)
			}
			if h.log("summer.call") != "" {
				t.Fatal("summer was called")
			}
		}},
		{"another module in the directory refuses", func(t *testing.T, h *scriptHarness) {
			dir := h.checkout()
			if err := os.Mkdir(dir, 0o755); err != nil {
				t.Fatal(err)
			}
			if err := os.WriteFile(filepath.Join(dir, "go.mod"), []byte("module example.com/other\n"), 0o644); err != nil {
				t.Fatal(err)
			}
			res := h.run("demo")
			expectCode(t, res, 1)
			expectContains(t, "stderr", res.stderr, "is not a SummerCMS framework checkout", "example.com/other")
			if h.log("summer.call") != "" || h.log("go.install") != "" {
				t.Fatal("the script went on after refusing the directory")
			}
		}},
		{"framework directory that is not a git repository refuses", func(t *testing.T, h *scriptHarness) {
			dir := h.checkout()
			if err := os.Mkdir(dir, 0o755); err != nil {
				t.Fatal(err)
			}
			if err := os.WriteFile(filepath.Join(dir, "go.mod"), []byte("module "+fwModule+"\n"), 0o644); err != nil {
				t.Fatal(err)
			}
			res := h.run("demo")
			expectCode(t, res, 1)
			expectContains(t, "stderr", res.stderr, "is not a git repository")
			if _, err := os.Stat(filepath.Join(dir, ".git")); !os.IsNotExist(err) {
				t.Fatalf("the script created .git: %v", err)
			}
		}},
		{"empty SHELL prints the generic hint", func(t *testing.T, h *scriptHarness) {
			res := h.mustRun("demo")
			expectHintSuffix(t, res.stdout, "\n==> summer is installed in "+h.gobin+", which is not on your PATH. Run this (and add it to your shell profile):\n  export PATH=\""+h.gobin+":$PATH\"\n")
		}},
		{"unset SHELL prints the generic hint", func(t *testing.T, h *scriptHarness) {
			h.unsetShell = true
			res := h.mustRun("demo")
			expectLacks(t, "stderr", res.stderr, "unbound variable")
			expectHintSuffix(t, res.stdout, exportHint(h.gobin, "and add it to your shell profile"))
		}},
		{"unknown SHELL prints the generic hint", func(t *testing.T, h *scriptHarness) {
			h.env = append(h.env, "SHELL=/bin/tcsh")
			res := h.mustRun("demo")
			expectHintSuffix(t, res.stdout, exportHint(h.gobin, "and add it to your shell profile"))
		}},
		{"fish SHELL prints fish_add_path", func(t *testing.T, h *scriptHarness) {
			h.env = append(h.env, "SHELL=/usr/bin/fish")
			res := h.mustRun("demo")
			expectHintSuffix(t, res.stdout, fishHint(h.gobin))
			expectContains(t, "stdout", res.stdout, "fish_add_path also keeps it for new fish sessions", `  fish_add_path "`+h.gobin+`"`)
			expectLacks(t, "stdout", res.stdout, "export PATH", "shell profile")
		}},
		{"zsh SHELL names ~/.zshrc", func(t *testing.T, h *scriptHarness) {
			h.env = append(h.env, "SHELL=/bin/zsh")
			res := h.mustRun("demo")
			expectHintSuffix(t, res.stdout, exportHint(h.gobin, "and add it to ~/.zshrc"))
			expectLacks(t, "stdout", res.stdout, "fish_add_path")
		}},
		{"bash SHELL names ~/.bashrc", func(t *testing.T, h *scriptHarness) {
			h.env = append(h.env, "SHELL=/usr/local/bin/bash")
			res := h.mustRun("demo")
			expectHintSuffix(t, res.stdout, exportHint(h.gobin, "and add it to ~/.bashrc"))
			expectLacks(t, "stdout", res.stdout, "fish_add_path")
		}},
		{"metacharacters in the dir are escaped for zsh", func(t *testing.T, h *scriptHarness) {
			metaGobin(t, h)
			h.env = append(h.env, "SHELL=/bin/zsh")
			res := h.mustRun("demo")
			want := "  export PATH=\"" + hintDir(h.root, false) + "/" + (`go bin\\x\"y\$HOME\` + "`" + `id\` + "`" + `"'!'"z`) + ":$PATH\"\n"
			expectContains(t, "stdout", res.stdout, want)
			expectHintSuffix(t, res.stdout, exportHint(h.gobin, "and add it to ~/.zshrc"))
		}},
		{"metacharacters in the dir are escaped for fish", func(t *testing.T, h *scriptHarness) {
			metaGobin(t, h)
			h.env = append(h.env, "SHELL=/usr/bin/fish")
			res := h.mustRun("demo")
			want := "  fish_add_path \"" + hintDir(h.root, true) + "/" + (`go bin\\x\"y\$HOME` + "`id`!z") + "\"\n"
			expectContains(t, "stdout", res.stdout, want)
			expectHintSuffix(t, res.stdout, fishHint(h.gobin))
		}},
		{"GOBIN on PATH prints no hint", func(t *testing.T, h *scriptHarness) {
			h.gobinOnPath = true
			h.env = append(h.env, "SHELL=/usr/bin/fish")
			res := h.mustRun("demo")
			expectLacks(t, "stdout", res.stdout, "export PATH", "fish_add_path", "not on your PATH")
		}},
		{"empty GOBIN installs into GOPATH/bin", func(t *testing.T, h *scriptHarness) {
			h.useGOBIN = false
			res := h.mustRun("demo")
			bin := filepath.Join(h.gopath, "bin")
			if _, err := os.Stat(filepath.Join(bin, "summer")); err != nil {
				t.Fatalf("summer not installed in GOPATH/bin: %v", err)
			}
			expectContains(t, "stderr", res.stderr, "installing summer into "+bin)
			expectContains(t, "stdout", res.stdout, `export PATH="`+bin+`:$PATH"`)
		}},
	}
	if len(cases) < 32 {
		t.Fatalf("only %d cases", len(cases))
	}
	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			tc.run(t, newScriptHarness(t))
		})
	}
}

// TestScriptShellcheck runs shellcheck on new.sh; it is skipped only when
// shellcheck is not installed.
func TestScriptShellcheck(t *testing.T) {
	sc, err := exec.LookPath("shellcheck")
	if err != nil {
		t.Skip("shellcheck not installed")
	}
	out, err := exec.Command(sc, "-s", "bash", "new.sh").CombinedOutput()
	if err != nil {
		t.Fatalf("shellcheck -s bash new.sh: %v\n%s", err, out)
	}
}