bake: initial implementation

Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>

bake/hcl_test.go

@@ -0,0 +1,57 @@
+package bake
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestParseHCL(t *testing.T) {
+	var dt = []byte(`
+	group "default" {
+		targets = ["db", "webapp"]
+	}
+
+	target "db" {
+		context = "./db"
+		tags = ["docker.io/tonistiigi/db"]
+	}
+
+	target "webapp" {
+		context = "./dir"
+		dockerfile = "Dockerfile-alternate"
+		args = {
+			buildno = "123"
+		}
+	}
+
+	target "cross" {
+		platforms = [
+			"linux/amd64",
+			"linux/arm64"
+		]
+	}
+
+	target "webapp-plus" {
+		inherits = ["webapp", "cross"]
+		args = {
+			IAMCROSS = "true"
+		}
+	}
+	`)
+
+	c, err := ParseHCL(dt)
+	require.NoError(t, err)
+
+	require.Equal(t, 1, len(c.Group))
+	require.Equal(t, []string{"db", "webapp"}, c.Group["default"].Targets)
+
+	require.Equal(t, 4, len(c.Target))
+	require.Equal(t, "./db", c.Target["db"].Context)
+
+	require.Equal(t, 1, len(c.Target["webapp"].Args))
+	require.Equal(t, "123", c.Target["webapp"].Args["buildno"])
+
+	require.Equal(t, 2, len(c.Target["cross"].Platforms))
+	require.Equal(t, []string{"linux/amd64", "linux/arm64"}, c.Target["cross"].Platforms)
+}