testing: migrate function-trace.sh

Change-Id: I44bd28165070f55f21b052bc02ba6f2ea5787a1d
2026-02-28 22:09:44 +00:00
parent fae0242f69
commit f4c92f8872
3 changed files with 42 additions and 70 deletions
@@ -0,0 +1,42 @@
+import pytest
+from testlib.fixtures.nix import Nix
+
+
+class TestFunctionTrace:
+    @pytest.fixture(autouse=True)
+    def setup(self, nix: Nix):
+        self.nix = nix
+
+    def call(self, expr: str) -> list[str]:
+        trace = (
+            self.nix.nix_instantiate(["--trace-function-calls", "--expr", expr]).run().stderr_plain
+        )
+        return [
+            " ".join(line.split(" ")[:-1])
+            for line in trace.splitlines()
+            if line.startswith("function-trace")
+        ]
+
+    def test_try_eval(self):
+        assert self.call('builtins.tryEval (throw "example")') == [
+            "function-trace entered «string»:1:1 at",
+            "function-trace entered «string»:1:19 at",
+            "function-trace exited «string»:1:19 at",
+            "function-trace exited «string»:1:1 at",
+        ]
+
+    @pytest.mark.parametrize(
+        "expr",
+        [
+            "({ x }: x) { }",
+            '({ x }: x) { x = "x"; y = "y"; }',
+            "(x: y: x + y) 1",
+            "(x: x) 1 2",
+            "1 2",
+        ],
+    )
+    def test_single_call(self, expr: str):
+        assert self.call(expr) == [
+            "function-trace entered «string»:1:1 at",
+            "function-trace exited «string»:1:1 at",
+        ]