Add dummy planners for a bunch of languages (#98)

## Summary
Add dummy planners for a bunch of languages; for now they are
placeholders that don't do anything, but it sets up the whole structure
so we can easily start editing them (or the community can contribute by
finding the right file).

In the process refactored the common types and utility functions used by
all planners into a `plansdk`.

## How was it tested?
`go test -v ./...`

Author: loreto

config.go

@@ -6,12 +6,12 @@ package devbox
 import (
 	"github.com/pkg/errors"
 	"go.jetpack.io/devbox/cuecfg"
-	"go.jetpack.io/devbox/planner"
+	"go.jetpack.io/devbox/planner/plansdk"
 )
 
 // Config defines a devbox environment as JSON.
 type Config struct {
-	planner.SharedPlan
+	plansdk.SharedPlan
 
 	// Packages is the slice of Nix packages that devbox makes available in
 	// its environment.

devbox.go

@@ -13,6 +13,7 @@ import (
 	"go.jetpack.io/devbox/nix"
 	"go.jetpack.io/devbox/pkgslice"
 	"go.jetpack.io/devbox/planner"
+	"go.jetpack.io/devbox/planner/plansdk"
 	"golang.org/x/exp/slices"
 )
 
@@ -99,13 +100,13 @@ func (d *Devbox) Build(opts ...docker.BuildOptions) error {
 
 // Plan creates a plan of the actions that devbox will take to generate its
 // environment.
-func (d *Devbox) Plan() *planner.Plan {
-	basePlan := &planner.Plan{
+func (d *Devbox) Plan() *plansdk.Plan {
+	basePlan := &plansdk.Plan{
 		DevPackages:     d.cfg.Packages,
 		RuntimePackages: d.cfg.Packages,
 		SharedPlan:      d.cfg.SharedPlan,
 	}
-	return planner.MergePlans(basePlan, planner.GetPlan(d.srcDir))
+	return plansdk.MergePlans(basePlan, planner.GetPlan(d.srcDir))
 }
 
 // Generate creates the directory of Nix files and the Dockerfile that define

devbox_test.go

@@ -8,7 +8,7 @@ import (
 
 	"github.com/bmatcuk/doublestar/v4"
 	"github.com/stretchr/testify/assert"
-	"go.jetpack.io/devbox/planner"
+	"go.jetpack.io/devbox/planner/plansdk"
 )
 
 func TestDevboxPlan(t *testing.T) {
@@ -45,7 +45,7 @@ func testIndividualPlan(t *testing.T, testPath string) {
 		data, err := os.ReadFile(goldenFile)
 		assert.NoError(err, "plan.json should be readable")
 
-		expected := &planner.Plan{}
+		expected := &plansdk.Plan{}
 		err = json.Unmarshal(data, &expected)
 		assert.NoError(err, "plan.json should parse correctly")
 		expected.Errors = nil

generate.go

@@ -14,7 +14,7 @@ import (
 
 	"github.com/pkg/errors"
 	"go.jetpack.io/devbox/debug"
-	"go.jetpack.io/devbox/planner"
+	"go.jetpack.io/devbox/planner/plansdk"
 )
 
 //go:embed tmpl/* tmpl/.*
@@ -23,7 +23,7 @@ var tmplFS embed.FS
 var shellFiles = []string{".gitignore", "shell.nix"}
 var buildFiles = []string{".gitignore", "development.nix", "runtime.nix", "Dockerfile", "Dockerfile.dockerignore"}
 
-func generate(rootPath string, plan *planner.Plan, files []string) error {
+func generate(rootPath string, plan *plansdk.Plan, files []string) error {
 	outPath := filepath.Join(rootPath, ".devbox/gen")
 
 	for _, file := range files {
@@ -36,7 +36,7 @@ func generate(rootPath string, plan *planner.Plan, files []string) error {
 	return nil
 }
 
-func writeFromTemplate(path string, plan *planner.Plan, tmplName string) error {
+func writeFromTemplate(path string, plan *plansdk.Plan, tmplName string) error {
 	embeddedPath := fmt.Sprintf("tmpl/%s.tmpl", tmplName)
 
 	// Should we clear the directory so we start "fresh"?

planner/empty/empty_planner.go

@@ -0,0 +1,26 @@
+// Copyright 2022 Jetpack Technologies Inc and contributors. All rights reserved.
+// Use of this source code is governed by the license in the LICENSE file.
+
+// Dummy empty planner. Mainly to serve as a template for how to start a new
+// planner.
+
+package empty
+
+import "go.jetpack.io/devbox/planner/plansdk"
+
+type Planner struct{}
+
+// Implements interface Planner (compile-time check)
+var _ plansdk.Planner = (*Planner)(nil)
+
+func (p *Planner) Name() string {
+	return "empty.Planner"
+}
+
+func (p *Planner) IsRelevant(srcDir string) bool {
+	return false
+}
+
+func (p *Planner) GetPlan(srcDir string) *plansdk.Plan {
+	return &plansdk.Plan{}
+}

planner/empty_planner.go

@@ -0,0 +1,25 @@
+// Copyright 2022 Jetpack Technologies Inc and contributors. All rights reserved.
+// Use of this source code is governed by the license in the LICENSE file.
+
+package c
+
+import (
+	"go.jetpack.io/devbox/planner/plansdk"
+)
+
+type Planner struct{}
+
+// Implements interface Planner (compile-time check)
+var _ plansdk.Planner = (*Planner)(nil)
+
+func (p *Planner) Name() string {
+	return "c.Planner"
+}
+
+func (p *Planner) IsRelevant(srcDir string) bool {
+	return false
+}
+
+func (p *Planner) GetPlan(srcDir string) *plansdk.Plan {
+	return &plansdk.Plan{}
+}

planner/languages/c/c_planner.go

@@ -0,0 +1,23 @@
+// Copyright 2022 Jetpack Technologies Inc and contributors. All rights reserved.
+// Use of this source code is governed by the license in the LICENSE file.
+
+package clojure
+
+import "go.jetpack.io/devbox/planner/plansdk"
+
+type Planner struct{}
+
+// Implements interface Planner (compile-time check)
+var _ plansdk.Planner = (*Planner)(nil)
+
+func (p *Planner) Name() string {
+	return "clojure.Planner"
+}
+
+func (p *Planner) IsRelevant(srcDir string) bool {
+	return false
+}
+
+func (p *Planner) GetPlan(srcDir string) *plansdk.Plan {
+	return &plansdk.Plan{}
+}

planner/languages/clojure/clojure_planner.go

@@ -0,0 +1,25 @@
+// Copyright 2022 Jetpack Technologies Inc and contributors. All rights reserved.
+// Use of this source code is governed by the license in the LICENSE file.
+
+package cplusplus
+
+import (
+	"go.jetpack.io/devbox/planner/plansdk"
+)
+
+type Planner struct{}
+
+// Implements interface Planner (compile-time check)
+var _ plansdk.Planner = (*Planner)(nil)
+
+func (p *Planner) Name() string {
+	return "cplusplus.Planner"
+}
+
+func (p *Planner) IsRelevant(srcDir string) bool {
+	return false
+}
+
+func (p *Planner) GetPlan(srcDir string) *plansdk.Plan {
+	return &plansdk.Plan{}
+}

planner/languages/cplusplus/cplusplus_planner.go

@@ -0,0 +1,25 @@
+// Copyright 2022 Jetpack Technologies Inc and contributors. All rights reserved.
+// Use of this source code is governed by the license in the LICENSE file.
+
+package crystal
+
+import (
+	"go.jetpack.io/devbox/planner/plansdk"
+)
+
+type Planner struct{}
+
+// Implements interface Planner (compile-time check)
+var _ plansdk.Planner = (*Planner)(nil)
+
+func (p *Planner) Name() string {
+	return "crystal.Planner"
+}
+
+func (p *Planner) IsRelevant(srcDir string) bool {
+	return false
+}
+
+func (p *Planner) GetPlan(srcDir string) *plansdk.Plan {
+	return &plansdk.Plan{}
+}