From fd61c226d494c0a6cb1cf17fcf2a7817593e0bb2 Mon Sep 17 00:00:00 2001
From: Elias Naur <mail@eliasnaur.com>
Date: Sun, 23 Feb 2020 13:52:03 +0100
Subject: [PATCH] internal/cmd/convertshaders: move shader converter to
 separate package

To use the converter from other packages, make the converter a
runnable command.

Signed-off-by: Elias Naur <mail@eliasnaur.com>
---
 gpu/gen.go                                          |  2 +-
 gpu/build.go => internal/cmd/convertshaders/main.go | 12 +++++++-----
 2 files changed, 8 insertions(+), 6 deletions(-)
 rename gpu/build.go => internal/cmd/convertshaders/main.go (97%)

diff --git a/gpu/gen.go b/gpu/gen.go
index f2e3c26a..709d0a78 100644
--- a/gpu/gen.go
+++ b/gpu/gen.go
@@ -2,4 +2,4 @@
 
 package gpu
 
-//go:generate go run build.go
+//go:generate go run ../internal/cmd/convertshaders -package gpu
diff --git a/gpu/build.go b/internal/cmd/convertshaders/main.go
similarity index 97%
rename from gpu/build.go
rename to internal/cmd/convertshaders/main.go
index e5f8d747..6b1aeaea 100644
--- a/gpu/build.go
+++ b/internal/cmd/convertshaders/main.go
@@ -1,12 +1,11 @@
 // SPDX-License-Identifier: Unlicense OR MIT
 
-// +build ignore
-
 package main
 
 import (
 	"bytes"
 	"encoding/json"
+	"flag"
 	"fmt"
 	"go/format"
 	"io/ioutil"
@@ -22,6 +21,8 @@ import (
 // multiple GPU backends (OpenGL ES, Direct3D 11...)
 // from a single source.
 
+var packageName = flag.String("package", "", "specify Go package name")
+
 type shaderArgs struct {
 	FetchColorExpr string
 	Header         string
@@ -60,14 +61,15 @@ const (
 )
 
 func main() {
+	flag.Parse()
 	if err := generate(); err != nil {
-		fmt.Fprintf(os.Stderr, "gpu generate: %v\n", err)
+		fmt.Fprintf(os.Stderr, "generate: %v\n", err)
 		os.Exit(1)
 	}
 }
 
 func generate() error {
-	tmp, err := ioutil.TempDir("", "gpu-generate")
+	tmp, err := ioutil.TempDir("", "shader-convert")
 	if err != nil {
 		return err
 	}
@@ -84,7 +86,7 @@ func generate() error {
 	}
 	var out bytes.Buffer
 	out.WriteString("// Code generated by build.go. DO NOT EDIT.\n\n")
-	out.WriteString("package gpu\n\n")
+	fmt.Fprintf(&out, "package %s\n\n", *packageName)
 	fmt.Fprintf(&out, "import %q\n\n", "gioui.org/gpu/backend")
 
 	out.WriteString("var (\n")