stdlib: os package

Signed-off-by: Solomon Hykes <solomon@dagger.io>

stdlib/js/react/react.cue

@@ -4,11 +4,12 @@ import (
 	"strings"
 
 	"dagger.io/dagger"
-	"dagger.io/dagger/op"
 	"dagger.io/alpine"
+	"dagger.io/os"
 )
 
 // A ReactJS application
+// FIXME: move this to a 'yarn' package for clarity
 #App: {
 	// Application source code
 	source: dagger.#Artifact
@@ -30,48 +31,36 @@ import (
 		script: string | *"build"
 	}
 
-	build: #up: [
-		op.#Load & {
-			from: alpine.#Image & {
-				package: bash: "=~5.1"
-				package: yarn: "=~1.22"
+	build: os.#Dir & {
+		from: ctr
+		path: "/build"
+	}
+
+	ctr: os.#Container & {
+		image: alpine.#Image & {
+			package: {
+				bash: "=~5.1"
+				yarn: "=~1.22"
 			}
-		},
-		op.#Exec & {
-			args: [
-				"/bin/bash",
-				"--noprofile",
-				"--norc",
-				"-eo",
-				"pipefail",
-				"-c",
-				"""
-					[ -n "$ENVFILE_NAME" ] && echo "$ENVFILE" > "$ENVFILE_NAME"
-					yarn install --production false
-					yarn run "$YARN_BUILD_SCRIPT"
-					mv "$YARN_BUILD_DIRECTORY" /build
-					""",
-			]
-			if env != _|_ {
-				"env": env
+		}
+		shell: path: "/bin/bash"
+		command: """
+			[ -n "$ENVFILE_NAME" ] && echo "$ENVFILE" > "$ENVFILE_NAME"
+			yarn install --production false
+			yarn run "$YARN_BUILD_SCRIPT"
+			mv "$YARN_BUILD_DIRECTORY" /build
+			"""
+		"env": env & {
+			YARN_BUILD_SCRIPT:    yarn.script
+			YARN_CACHE_FOLDER:    "/cache/yarn"
+			YARN_BUILD_DIRECTORY: yarn.buildDir
+			if writeEnvFile != "" {
+				ENVFILE_NAME: writeEnvFile
+				ENVFILE:      strings.Join([ for k, v in env {"\(k)=\(v)"}], "\n")
 			}
-			"env": {
-				YARN_BUILD_SCRIPT:    yarn.script
-				YARN_CACHE_FOLDER:    "/cache/yarn"
-				YARN_BUILD_DIRECTORY: yarn.buildDir
-				if writeEnvFile != "" {
-					ENVFILE_NAME: writeEnvFile
-					ENVFILE:      strings.Join([ for k, v in env {"\(k)=\(v)"}], "\n")
-				}
-			}
-			dir: "/src"
-			mount: {
-				"/src": from: source
-				"/cache/yarn": "cache"
-			}
-		},
-		op.#Subdir & {
-			dir: "/build"
-		},
-	]
+		}
+		dir: "/src"
+		mount: "/src": from: source
+		cache: "/cache/yarn": true
+	}
 }