Cletus plugin kit: rules for coding agents, specification, host API, style guide, worker SDK and cletus-plugin tool

sdk/cmd/cletus-plugin/build.go

@@ -0,0 +1,51 @@
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+)
+
+// goEnv is the environment every build and test runs with: no cgo, no
+// enclosing go.work, the plugin's vendor folder.
+func goEnv(goos, goarch string) []string {
+	env := append(os.Environ(), "CGO_ENABLED=0", "GOWORK=off")
+	if goos != "" {
+		env = append(env, "GOOS="+goos, "GOARCH="+goarch)
+	}
+	return env
+}
+
+// goRun runs a go command in dir and returns its combined output.
+func goRun(dir string, env []string, args ...string) (string, error) {
+	cmd := exec.Command("go", args...)
+	cmd.Dir = dir
+	cmd.Env = env
+	var out bytes.Buffer
+	cmd.Stdout = &out
+	cmd.Stderr = &out
+	err := cmd.Run()
+	return out.String(), err
+}
+
+// buildWorker builds ./cmd/worker for this machine into a temporary folder.
+func buildWorker(dir string) (string, func(), error) {
+	tmp, err := os.MkdirTemp("", "cletus-plugin-")
+	if err != nil {
+		return "", nil, err
+	}
+	cleanup := func() { os.RemoveAll(tmp) }
+	name := "worker"
+	if runtime.GOOS == "windows" {
+		name += ".exe"
+	}
+	bin := filepath.Join(tmp, name)
+	if out, err := goRun(dir, goEnv("", ""), "build", "-trimpath", "-o", bin, "./cmd/worker"); err != nil {
+		cleanup()
+		return "", nil, fmt.Errorf("the worker doesn't build:\n%s", out)
+	}
+	return bin, cleanup, nil
+}