utils: add trim_version() function

Add a helper function that returns just the first <num_parts> of <version>,
split by periods.  For example, trim_version("1.2.3", 2) will return "1.2".

This should help reduce the spread of numerous copies of this idea across
classes and recipes.

Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Saul Wold <sgw@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 20 insertions, 0 deletions

diff --git a/meta/lib/oe/tests/test_utils.py b/meta/lib/oe/tests/test_utils.py
index 466c47eb9c..78b1361161 100644
--- a/meta/lib/oe/tests/test_utils.py
+++ b/meta/lib/oe/tests/test_utils.py
@@ -25,3 +25,23 @@ class TestPackagesFilterOutSystem(unittest.TestCase):
         d.setVar("PACKAGES", "foo foo-data foo-locale-en-gb")
         pkgs = oe.utils.packages_filter_out_system(d)
         self.assertEqual(pkgs, ["foo-data"])
+
+
+class TestTrimVersion(unittest.TestCase):
+    def test_version_exception(self):
+        with self.assertRaises(TypeError):
+            trim_version(None, 2)
+        with self.assertRaises(TypeError):
+            trim_version((1, 2, 3), 2)
+
+    def test_num_exception(self):
+        with self.assertRaises(ValueError):
+            trim_version("1.2.3", 0)
+        with self.assertRaises(ValueError):
+            trim_version("1.2.3", -1)
+
+    def test_valid(self):
+        self.assertEqual(trim_version("1.2.3", 1), "1")
+        self.assertEqual(trim_version("1.2.3", 2), "1.2")
+        self.assertEqual(trim_version("1.2.3", 3), "1.2.3")
+        self.assertEqual(trim_version("1.2.3", 4), "1.2.3")