From 8bcb027efc780250578ffdff93362ee092d3caa8 Mon Sep 17 00:00:00 2001
From: Sytze Harkema <sharkema@users.noreply.github.com>
Date: Mon, 21 Feb 2022 09:44:50 +0100
Subject: [PATCH] feat: remove go dependency for every build step

---
 Makefile       |  1 +
 sg/generate.go |  3 ++-
 sg/makefile.go | 13 ++++++++++---
 3 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/Makefile b/Makefile
index 9d4fd0cf..414395b0 100644
--- a/Makefile
+++ b/Makefile
@@ -10,6 +10,7 @@ $(sagefile):
 	@cd .sage && go mod tidy && go run .
 
 .PHONY: sage
+sage: $(shell git clean -fxq $(sagefile))
 sage: $(sagefile)
 
 .PHONY: update-sage
diff --git a/sg/generate.go b/sg/generate.go
index be477167..99697361 100644
--- a/sg/generate.go
+++ b/sg/generate.go
@@ -14,6 +14,7 @@ import (
 // GenerateMakefiles defines which Makefiles should be generated.
 func GenerateMakefiles(mks ...Makefile) {
 	ctx := WithLogger(context.Background(), NewLogger("sage"))
+	Logger(ctx).Println("building binary and generating Makefiles...")
 	if len(mks) == 0 {
 		panic("no makefiles to generate, see https://github.com/einride/sage#readme for more info")
 	}
@@ -67,7 +68,7 @@ func GenerateMakefiles(mks ...Makefile) {
 		mk := codegen.NewMakefile(codegen.FileConfig{
 			GeneratedBy: "go.einride.tech/sage",
 		})
-		if err := generateMakefile(mk, pkg, v, mks...); err != nil {
+		if err := generateMakefile(ctx, mk, pkg, v, mks...); err != nil {
 			panic(err)
 		}
 		if err := os.WriteFile(v.Path, mk.RawContent(), 0o600); err != nil {
diff --git a/sg/makefile.go b/sg/makefile.go
index d9cc4fef..46cb4c74 100644
--- a/sg/makefile.go
+++ b/sg/makefile.go
@@ -1,6 +1,7 @@
 package sg
 
 import (
+	"context"
 	"fmt"
 	"go/ast"
 	"go/doc"
@@ -43,7 +44,7 @@ func (m Makefile) defaultTargetName() string {
 	return result
 }
 
-func generateMakefile(g *codegen.File, pkg *doc.Package, mk Makefile, mks ...Makefile) error {
+func generateMakefile(ctx context.Context, g *codegen.File, pkg *doc.Package, mk Makefile, mks ...Makefile) error {
 	includePath, err := filepath.Rel(filepath.Dir(mk.Path), FromSageDir())
 	if err != nil {
 		return err
@@ -56,11 +57,17 @@ func generateMakefile(g *codegen.File, pkg *doc.Package, mk Makefile, mks ...Mak
 	g.P()
 	g.P("sagefile := ", filepath.Join(includePath, binDir, sageFileBinary))
 	g.P()
-	g.P(".PHONY: $(sagefile)")
-	g.P("$(sagefile):")
+
+	dependencies := fmt.Sprintf(" %s/go.mod %s/*.go", includePath, includePath)
+	if strings.TrimSpace(Output(Command(ctx, "go", "list", "-m"))) == "go.einride.tech/sage" {
+		g.P(".PHONY: $(sagefile)")
+		dependencies = ""
+	}
+	g.P("$(sagefile):", dependencies)
 	g.P("\t@cd ", includePath, " && go mod tidy && go run .")
 	g.P()
 	g.P(".PHONY: sage")
+	g.P("sage: $(shell git clean -fxq $(sagefile))")
 	g.P("sage: $(sagefile)")
 	g.P()
 	g.P(".PHONY: update-sage")