gopherjs · myitcv · Apr 18, 2018 · Apr 15, 2018
diff --git a/compiler/prelude/formatpreludejs.go b/compiler/prelude/formatpreludejs.go
@@ -0,0 +1,56 @@
+// +build ignore
+
+package main
+
+import (
+	"fmt"
+	"go/build"
+	"io/ioutil"
+	"log"
+	"os/exec"
+	"path/filepath"
+	"strings"
+)
+
+func main() {
+	if err := run(); err != nil {
+		log.Fatalln(err)
+	}
+}
+
+func run() error {
+	bpkg, err := build.Import("github.com/gopherjs/gopherjs", "", build.FindOnly)
+	if err != nil {
+		return fmt.Errorf("failed to locate path for github.com/gopherjs/gopherjs/compiler/prelude: %v", err)
+	}
+
+	preludeDir := filepath.Join(bpkg.Dir, "compiler", "prelude")
+
+	args := []string{
+		filepath.Join(bpkg.Dir, "node_modules", ".bin", "prettier"),
+		"--config",
+		filepath.Join(preludeDir, "prettier_options.json"),
+		"--write",
+	}
+
+	fis, err := ioutil.ReadDir(preludeDir)
+	if err != nil {
+		return fmt.Errorf("failed to list contents of %v: %v", preludeDir, err)
+	}
+	for _, fi := range fis {
+		fn := fi.Name()
+		if !strings.HasSuffix(fn, ".js") || strings.HasSuffix(fn, ".min.js") {
+			continue
+		}
+		args = append(args, fn)
+	}
+
+	cmd := exec.Command(args[0], args[1:]...)
+
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		return fmt.Errorf("failed to run %v: %v\n%s", strings.Join(args, " "), err, string(out))
+	}
+
+	return nil
+}
diff --git a/compiler/prelude/generate.go b/compiler/prelude/generate.go
@@ -0,0 +1,4 @@
+package prelude
+
+//go:generate go run formatpreludejs.go
+//go:generate go run genprelude.go
diff --git a/compiler/prelude/genmin.go b/compiler/prelude/genmin.go
diff --git a/compiler/prelude/genprelude.go b/compiler/prelude/genprelude.go
@@ -0,0 +1,96 @@
+// +build ignore
+
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"go/build"
+	"io/ioutil"
+	"log"
+	"os/exec"
+	"path/filepath"
+	"strings"
+)
+
+const (
+	fn    = "prelude.go"
+	minFn = "prelude_min.go"
+)
+
+func main() {
+	if err := run(); err != nil {
+		log.Fatalln(err)
+	}
+}
+
+func run() error {
+	bpkg, err := build.Import("github.com/gopherjs/gopherjs", "", build.FindOnly)
+	if err != nil {
+		return fmt.Errorf("failed to locate path for github.com/gopherjs/gopherjs: %v", err)
+	}
+
+	preludeDir := filepath.Join(bpkg.Dir, "compiler", "prelude")
+
+	files := []string{
+		"prelude.js",
+		"numeric.js",
+		"types.js",
+		"goroutines.js",
+		"jsmapping.js",
+	}
+
+	prelude := new(bytes.Buffer)
+
+	for _, f := range files {
+		p := filepath.Join(preludeDir, f)
+		out, err := ioutil.ReadFile(p)
+		if err != nil {
+			return fmt.Errorf("failed to read from %v: %v", p, err)
+		}
+		if _, err := prelude.Write(out); err != nil {
+			return fmt.Errorf("failed to append prelude: %v", err)
+		}
+	}
+
+	args := append([]string{
+		filepath.Join(bpkg.Dir, "node_modules", ".bin", "uglifyjs"),
+		"--config-file",
+		filepath.Join(preludeDir, "uglifyjs_options.json"),
+	}, files...)
+
+	stderr := new(bytes.Buffer)
+
+	cmd := exec.Command(args[0], args[1:]...)
+	cmd.Stderr = stderr
+
+	minout, err := cmd.Output()
+	if err != nil {
+		return fmt.Errorf("failed to run %v: %v\n%s", strings.Join(args, " "), err, stderr.Bytes())
+	}
+
+	err = writeOutput("prelude.go", ""+
+		"// Prelude is the GopherJS JavaScript interop layer.\n"+
+		"const Prelude = %q", prelude.Bytes())
+
+	if err != nil {
+		return err
+	}
+
+	err = writeOutput("prelude_min.go", ""+
+		"// Minified is an uglifyjs-minified version of Prelude.\n"+
+		"const Minified = %q", minout)
+
+	return err
+}
+
+func writeOutput(fn string, format string, byts []byte) error {
+	content := fmt.Sprintf("// Code generated by genprelude; DO NOT EDIT.\n\n"+
+		"package prelude\n\n"+format+"\n", byts)
+
+	if err := ioutil.WriteFile(fn, []byte(content), 0644); err != nil {
+		return fmt.Errorf("failed to write to %v: %v", fn, err)
+	}
+
+	return nil
+}