1 files changed, 91 insertions, 0 deletions
diff --git a/integration-cli/docker_cli_diff_test.go b/integration-cli/docker_cli_diff_test.go
new file mode 100644
index 0000000000..478ebd2df1
--- /dev/null
+++ b/integration-cli/docker_cli_diff_test.go
@@ -0,0 +1,91 @@
+package main
+
+import (
+	"fmt"
+	"os/exec"
+	"strings"
+	"testing"
+)
+
+// ensure that an added file shows up in docker diff
+func TestDiffFilenameShownInOutput(t *testing.T) {
+	containerCmd := `echo foo > /root/bar`
+	runCmd := exec.Command(dockerBinary, "run", "-d", "busybox", "sh", "-c", containerCmd)
+	cid, _, err := runCommandWithOutput(runCmd)
+	errorOut(err, t, fmt.Sprintf("failed to start the container: %v", err))
+
+	cleanCID := stripTrailingCharacters(cid)
+
+	diffCmd := exec.Command(dockerBinary, "diff", cleanCID)
+	out, _, err := runCommandWithOutput(diffCmd)
+	errorOut(err, t, fmt.Sprintf("failed to run diff: %v %v", out, err))
+
+	found := false
+	for _, line := range strings.Split(out, "\n") {
+		if strings.Contains("A /root/bar", line) {
+			found = true
+			break
+		}
+	}
+	if !found {
+		t.Errorf("couldn't find the new file in docker diff's output: %v", out)
+	}
+	deleteContainer(cleanCID)
+
+	logDone("diff - check if created file shows up")
+}
+
+// test to ensure GH #3840 doesn't occur any more
+func TestDiffEnsureDockerinitFilesAreIgnored(t *testing.T) {
+	// this is a list of files which shouldn't show up in `docker diff`
+	dockerinitFiles := []string{"/etc/resolv.conf", "/etc/hostname", "/etc/hosts", "/.dockerinit", "/.dockerenv"}
+
+	// we might not run into this problem from the first run, so start a few containers
+	for i := 0; i < 20; i++ {
+		containerCmd := `echo foo > /root/bar`
+		runCmd := exec.Command(dockerBinary, "run", "-d", "busybox", "sh", "-c", containerCmd)
+		cid, _, err := runCommandWithOutput(runCmd)
+		errorOut(err, t, fmt.Sprintf("%s", err))
+
+		cleanCID := stripTrailingCharacters(cid)
+
+		diffCmd := exec.Command(dockerBinary, "diff", cleanCID)
+		out, _, err := runCommandWithOutput(diffCmd)
+		errorOut(err, t, fmt.Sprintf("failed to run diff: %v %v", out, err))
+
+		deleteContainer(cleanCID)
+
+		for _, filename := range dockerinitFiles {
+			if strings.Contains(out, filename) {
+				t.Errorf("found file which should've been ignored %v in diff output", filename)
+			}
+		}
+	}
+
+	logDone("diff - check if ignored files show up in diff")
+}
+
+func TestDiffEnsureOnlyKmsgAndPtmx(t *testing.T) {
+	runCmd := exec.Command(dockerBinary, "run", "-d", "busybox", "sleep 0")
+	cid, _, err := runCommandWithOutput(runCmd)
+	errorOut(err, t, fmt.Sprintf("%s", err))
+	cleanCID := stripTrailingCharacters(cid)
+
+	diffCmd := exec.Command(dockerBinary, "diff", cleanCID)
+	out, _, err := runCommandWithOutput(diffCmd)
+	errorOut(err, t, fmt.Sprintf("failed to run diff: %v %v", out, err))
+	deleteContainer(cleanCID)
+
+	expected := map[string]bool{
+		"C /dev":      true,
+		"A /dev/full": true, // busybox
+		"C /dev/ptmx": true, // libcontainer
+		"A /dev/kmsg": true, // lxc
+	}
+
+	for _, line := range strings.Split(out, "\n") {
+		if line != "" && !expected[line] {
+			t.Errorf("'%s' is shown in the diff but shouldn't", line)
+		}
+	}
+}