1 files changed, 95 insertions, 0 deletions
diff --git a/lib/tests/misc.nix b/lib/tests/misc.nix
index b072f058d727..aa587f52c4ac 100644
--- a/lib/tests/misc.nix
+++ b/lib/tests/misc.nix
@@ -631,6 +631,101 @@ runTests {
     ];
   };
 
+  testSplitStringBySimpleDelimiter = {
+    expr = strings.splitStringBy (
+      prev: curr:
+      builtins.elem curr [
+        "."
+        "-"
+      ]
+    ) false "foo.bar-baz";
+    expected = [
+      "foo"
+      "bar"
+      "baz"
+    ];
+  };
+
+  testSplitStringByLeadingDelimiter = {
+    expr = strings.splitStringBy (prev: curr: builtins.elem curr [ "." ]) false ".foo.bar.baz";
+    expected = [
+      ""
+      "foo"
+      "bar"
+      "baz"
+    ];
+  };
+
+  testSplitStringByTrailingDelimiter = {
+    expr = strings.splitStringBy (prev: curr: builtins.elem curr [ "." ]) false "foo.bar.baz.";
+    expected = [
+      "foo"
+      "bar"
+      "baz"
+      ""
+    ];
+  };
+
+  testSplitStringByMultipleConsecutiveDelimiters = {
+    expr = strings.splitStringBy (prev: curr: builtins.elem curr [ "." ]) false "foo...bar";
+    expected = [
+      "foo"
+      ""
+      ""
+      "bar"
+    ];
+  };
+
+  testSplitStringByKeepingSplitChar = {
+    expr = strings.splitStringBy (prev: curr: builtins.elem curr [ "." ]) true "foo.bar.baz";
+    expected = [
+      "foo"
+      ".bar"
+      ".baz"
+    ];
+  };
+
+  testSplitStringByCaseTransition = {
+    expr = strings.splitStringBy (
+      prev: curr: builtins.match "[a-z]" prev != null && builtins.match "[A-Z]" curr != null
+    ) true "fooBarBaz";
+    expected = [
+      "foo"
+      "Bar"
+      "Baz"
+    ];
+  };
+
+  testSplitStringByEmptyString = {
+    expr = strings.splitStringBy (prev: curr: builtins.elem curr [ "." ]) false "";
+    expected = [ "" ];
+  };
+
+  testSplitStringByComplexPredicate = {
+    expr = strings.splitStringBy (
+      prev: curr:
+      prev != ""
+      && curr != ""
+      && builtins.match "[0-9]" prev != null
+      && builtins.match "[a-z]" curr != null
+    ) true "123abc456def";
+    expected = [
+      "123"
+      "abc456"
+      "def"
+    ];
+  };
+
+  testSplitStringByUpperCaseStart = {
+    expr = strings.splitStringBy (prev: curr: builtins.match "[A-Z]" curr != null) true "FooBarBaz";
+    expected = [
+      ""
+      "Foo"
+      "Bar"
+      "Baz"
+    ];
+  };
+
   testEscapeShellArg = {
     expr = strings.escapeShellArg "esc'ape\nme";
     expected = "'esc'\\''ape\nme'";