* Export the nix-env derivation name parsing and version comparison

  logic through the `parseDrvName' and `compareVersions' primops.
  This will allow expressions to easily check whether some dependency
  is a specific needed version or falls in some version range.  See
  tests/lang/eval-okay-versions.nix for examples.

1 files changed, 40 insertions, 0 deletions

diff --git a/tests/lang/eval-okay-versions.nix b/tests/lang/eval-okay-versions.nix
new file mode 100644
index 000000000000..e63c36586bb6
--- /dev/null
+++ b/tests/lang/eval-okay-versions.nix
@@ -0,0 +1,40 @@
+let
+
+  name1 = "hello-1.0.2";
+  name2 = "hello";
+  name3 = "915resolution-0.5.2";
+  name4 = "xf86-video-i810-1.7.4";
+
+  eq = 0;
+  lt = builtins.sub 0 1;
+  gt = 1;
+
+  versionTest = v1: v2: expected:
+    let d1 = builtins.compareVersions v1 v2;
+        d2 = builtins.compareVersions v2 v1;
+    in d1 == builtins.sub 0 d2 && d1 == expected;
+
+  tests = [
+    ((builtins.parseDrvName name1).name == "hello")
+    ((builtins.parseDrvName name1).version == "1.0.2")
+    ((builtins.parseDrvName name2).name == "hello")
+    ((builtins.parseDrvName name2).version == "")
+    ((builtins.parseDrvName name3).name == "915resolution")
+    ((builtins.parseDrvName name3).version == "0.5.2")
+    ((builtins.parseDrvName name4).name == "xf86-video-i810")
+    ((builtins.parseDrvName name4).version == "1.7.4")
+    (versionTest "1.0" "2.3" lt)
+    (versionTest "2.1" "2.3" lt)
+    (versionTest "2.3" "2.3" eq)
+    (versionTest "2.5" "2.3" gt)
+    (versionTest "3.1" "2.3" gt)
+    (versionTest "2.3.1" "2.3" gt)
+    (versionTest "2.3.1" "2.3a" gt)
+    (versionTest "2.3pre1" "2.3" lt)
+    (versionTest "2.3pre3" "2.3pre12" lt)
+    (versionTest "2.3a" "2.3c" lt)
+    (versionTest "2.3pre1" "2.3c" lt)
+    (versionTest "2.3pre1" "2.3q" lt)
+  ];
+
+in (import ./lib.nix).and tests