1 files changed, 35 insertions, 1 deletions
diff --git a/lib/path/tests/unit.nix b/lib/path/tests/unit.nix
index da2c950de914..a1a45173a909 100644
--- a/lib/path/tests/unit.nix
+++ b/lib/path/tests/unit.nix
@@ -3,9 +3,43 @@
 { libpath }:
 let
   lib = import libpath;
-  inherit (lib.path) subpath;
+  inherit (lib.path) append subpath;
 
   cases = lib.runTests {
+    # Test examples from the lib.path.append documentation
+    testAppendExample1 = {
+      expr = append /foo "bar/baz";
+      expected = /foo/bar/baz;
+    };
+    testAppendExample2 = {
+      expr = append /foo "./bar//baz/./";
+      expected = /foo/bar/baz;
+    };
+    testAppendExample3 = {
+      expr = append /. "foo/bar";
+      expected = /foo/bar;
+    };
+    testAppendExample4 = {
+      expr = (builtins.tryEval (append "/foo" "bar")).success;
+      expected = false;
+    };
+    testAppendExample5 = {
+      expr = (builtins.tryEval (append /foo /bar)).success;
+      expected = false;
+    };
+    testAppendExample6 = {
+      expr = (builtins.tryEval (append /foo "")).success;
+      expected = false;
+    };
+    testAppendExample7 = {
+      expr = (builtins.tryEval (append /foo "/bar")).success;
+      expected = false;
+    };
+    testAppendExample8 = {
+      expr = (builtins.tryEval (append /foo "../bar")).success;
+      expected = false;
+    };
+
     # Test examples from the lib.path.subpath.isValid documentation
     testSubpathIsValidExample1 = {
       expr = subpath.isValid null;