test(docs): generate and verify help-all output

Author: rokath

README.md

@@ -110,7 +110,8 @@ This simplified [diagram](https://github.com/jgraph/drawio) shows how Trice work
 - [Trice User Manual](./docs/TriceUserManual.md) (includes updated information from the interrupt blog)
 - Check [issues](https://github.com/rokath/trice/issues) and [discussions](https://github.com/rokath/trice/discussions), including closed items
 - Read the target source code, especially [triceDefaultConfig.h](./src/triceDefaultConfig.h)
-- View [CLI](https://en.wikipedia.org/wiki/Command-line_interface) options by running `trice help -all` in a terminal or reading [tricehelpall_test.go](./internal/args/tricehelpall_test.go)
+- View [CLI](https://en.wikipedia.org/wiki/Command-line_interface) options by running `trice help -all` in a terminal or reading the generated file [trice-help-all.txt](./docs/ref/trice-help-all.txt)
+- Refresh the checked-in CLI help documentation with `go generate ./internal/args`
 - Look at and modify [./internal/emitter/lineTransformerANSI.go](./internal/emitter/lineTransformerANSI.go) if needed (requires running `go install ./cmd/trice/...` afterwards)
 
 ## Debugging with VS-Code and Clang

cmd/generate-helpall-doc/main.go

@@ -0,0 +1,46 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/rokath/trice/internal/args"
+)
+
+const outputFile = "docs/ref/trice-help-all.txt"
+
+func main() {
+	text, err := args.RenderHelpText("-all")
+	if err != nil {
+		fail("render help text", err)
+	}
+
+	root, err := repoRoot()
+	if err != nil {
+		fail("locate repository root", err)
+	}
+	targetFile := filepath.Join(root, outputFile)
+
+	if err := os.MkdirAll(filepath.Dir(targetFile), 0o755); err != nil {
+		fail("create output directory", err)
+	}
+	if err := os.WriteFile(targetFile, []byte(text), 0o644); err != nil {
+		fail("write help output", err)
+	}
+}
+
+func repoRoot() (string, error) {
+	wd, err := os.Getwd()
+	if err != nil {
+		return "", err
+	}
+	// go generate runs in the package directory of the file containing the directive.
+	// The directive lives in internal/args, so the repository root is two levels up.
+	return filepath.Clean(filepath.Join(wd, "..", "..")), nil
+}
+
+func fail(step string, err error) {
+	fmt.Fprintf(os.Stderr, "%s: %v\n", step, err)
+	os.Exit(1)
+}