fix: buildkit cache prune (#238)

Signed-off-by: Shubharanshu Mahapatra <[email protected]>

Author: Shubhranshu153

tests/builder_prune.go

@@ -24,23 +24,19 @@ func BuilderPrune(o *option.Option) {
 			`, localImages[defaultImage]))
 			ginkgo.DeferCleanup(os.RemoveAll, buildContext)
 			command.RemoveAll(o)
+
+			// Build the Image and remove the resource to be able to prune
+			command.Run(o, "build", buildContext)
+			command.RemoveAll(o)
 		})
 		ginkgo.AfterEach(func() {
 			command.RemoveAll(o)
 		})
 		ginkgo.It("should prune the builder cache successfully", func() {
-			command.Run(o, "build", "--output=type=docker", buildContext)
-			// There is no interface to validate the current builder cache size.
-			// To validate in Buildkit, run `buildctl du -v`.
-			args := []string{"builder", "prune"}
-
-			// TODO(macedonv): remove after nerdctlv2 is supported across all platforms.
-			if o.IsNerdctlV2() {
-				// Do not prompt for user response during automated testing.
-				args = append(args, "--force")
-			}
-
+			buildCacheShouldExist()
+			args := []string{"builder", "prune", "--force"}
 			command.Run(o, args...)
+			buildCacheShouldNotExist()
 		})
 	})
 }

tests/tests.go

@@ -234,3 +234,21 @@ func buildImage(o *option.Option, imageName string) {
 	ginkgo.DeferCleanup(os.RemoveAll, buildContext)
 	command.Run(o, "build", "-q", "-t", imageName, buildContext)
 }
+
+func buildCacheShouldExist() {
+	buildctlOpts, err := option.New([]string{"buildctl"})
+	if err != nil {
+		ginkgo.Fail(err.Error())
+	}
+	cmdOut := command.Run(buildctlOpts, "du", "--format", "json")
+	gomega.Expect(strings.TrimSpace(string(cmdOut.Out.Contents()))).ToNot(gomega.Equal("null"))
+}
+
+func buildCacheShouldNotExist() {
+	buildctlOpts, err := option.New([]string{"buildctl"})
+	if err != nil {
+		ginkgo.Fail(err.Error())
+	}
+	cmdOut := command.Run(buildctlOpts, "du", "--format", "json")
+	gomega.Expect(strings.TrimSpace(string(cmdOut.Out.Contents()))).To(gomega.Equal("null"))
+}