Move DiscoverContainerfile to pkg/util directory

Then podman can use it

Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>

cmd/buildah/bud.go

@@ -12,6 +12,7 @@ import (
 	"github.com/containers/buildah/imagebuildah"
 	buildahcli "github.com/containers/buildah/pkg/cli"
 	"github.com/containers/buildah/pkg/parse"
+	buildahutil "github.com/containers/buildah/pkg/util"
 	"github.com/containers/buildah/util"
 	"github.com/containers/common/pkg/auth"
 	"github.com/pkg/errors"
@@ -191,7 +192,7 @@ func budCmd(c *cobra.Command, inputArgs []string, iopts budOptions) error {
 
 	if len(containerfiles) == 0 {
 		// Try to find the Containerfile/Dockerfile within the contextDir
-		containerfile, err := discoverContainerfile(contextDir)
+		containerfile, err := buildahcli.DiscoverContainerfile(contextDir)
 		if err != nil {
 			return err
 		}
@@ -384,44 +385,3 @@ func budCmd(c *cobra.Command, inputArgs []string, iopts budOptions) error {
 	}
 	return err
 }
-
-// discoverContainerfile tries to find a Containerfile or a Dockerfile within the provided `path`.
-func discoverContainerfile(path string) (foundCtrFile string, err error) {
-	// Test for existence of the file
-	target, err := os.Stat(path)
-	if err != nil {
-		return "", errors.Wrap(err, "discovering Containerfile")
-	}
-
-	switch mode := target.Mode(); {
-	case mode.IsDir():
-		// If the path is a real directory, we assume a Containerfile or a Dockerfile within it
-		ctrfile := filepath.Join(path, "Containerfile")
-
-		// Test for existence of the Containerfile file
-		file, err := os.Stat(ctrfile)
-		if err != nil {
-			// See if we have a Dockerfile within it
-			ctrfile = filepath.Join(path, "Dockerfile")
-
-			// Test for existence of the Dockerfile file
-			file, err = os.Stat(ctrfile)
-			if err != nil {
-				return "", errors.Wrap(err, "cannot find Containerfile or Dockerfile in context directory")
-			}
-		}
-
-		// The file exists, now verify the correct mode
-		if mode := file.Mode(); mode.IsRegular() {
-			foundCtrFile = ctrfile
-		} else {
-			return "", errors.Errorf("assumed Containerfile %q is not a file", ctrfile)
-		}
-
-	case mode.IsRegular():
-		// If the context dir is a file, we assume this as Containerfile
-		foundCtrFile = path
-	}
-
-	return foundCtrFile, nil
-}

pkg/util/test/test1/Containerfile

@@ -0,0 +1 @@
+from scratch

pkg/util/test/test1/Dockerfile

@@ -0,0 +1 @@
+from scratch

pkg/util/test/test2/Dockerfile

@@ -0,0 +1 @@
+from scratch

pkg/util/util.go

@@ -0,0 +1,49 @@
+package util
+
+import (
+	"os"
+	"path/filepath"
+
+	"github.com/pkg/errors"
+)
+
+// DiscoverContainerfile tries to find a Containerfile or a Dockerfile within the provided `path`.
+func DiscoverContainerfile(path string) (foundCtrFile string, err error) {
+	// Test for existence of the file
+	target, err := os.Stat(path)
+	if err != nil {
+		return "", errors.Wrap(err, "discovering Containerfile")
+	}
+
+	switch mode := target.Mode(); {
+	case mode.IsDir():
+		// If the path is a real directory, we assume a Containerfile or a Dockerfile within it
+		ctrfile := filepath.Join(path, "Containerfile")
+
+		// Test for existence of the Containerfile file
+		file, err := os.Stat(ctrfile)
+		if err != nil {
+			// See if we have a Dockerfile within it
+			ctrfile = filepath.Join(path, "Dockerfile")
+
+			// Test for existence of the Dockerfile file
+			file, err = os.Stat(ctrfile)
+			if err != nil {
+				return "", errors.Wrap(err, "cannot find Containerfile or Dockerfile in context directory")
+			}
+		}
+
+		// The file exists, now verify the correct mode
+		if mode := file.Mode(); mode.IsRegular() {
+			foundCtrFile = ctrfile
+		} else {
+			return "", errors.Errorf("assumed Containerfile %q is not a file", ctrfile)
+		}
+
+	case mode.IsRegular():
+		// If the context dir is a file, we assume this as Containerfile
+		foundCtrFile = path
+	}
+
+	return foundCtrFile, nil
+}

pkg/util/util_test.go

@@ -0,0 +1,32 @@
+package util
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestDiscoverContainerfile(t *testing.T) {
+	_, err := DiscoverContainerfile("./bogus")
+	assert.NotNil(t, err)
+
+	_, err = DiscoverContainerfile("./")
+	assert.NotNil(t, err)
+
+	name, err := DiscoverContainerfile("test/test1/Dockerfile")
+	assert.Nil(t, err)
+	assert.Equal(t, name, "test/test1/Dockerfile")
+
+	name, err = DiscoverContainerfile("test/test1/Containerfile")
+	assert.Nil(t, err)
+	assert.Equal(t, name, "test/test1/Containerfile")
+
+	name, err = DiscoverContainerfile("test/test1")
+	assert.Nil(t, err)
+	assert.Equal(t, name, "test/test1/Containerfile")
+
+	name, err = DiscoverContainerfile("test/test2")
+	assert.Nil(t, err)
+	assert.Equal(t, name, "test/test2/Dockerfile")
+
+}