From b707403a308030739dfeacc5b0aaaeef8ba3f633 Mon Sep 17 00:00:00 2001
From: "Commentator2.0" <lix@crystal-cavern.systems>
Date: Sat, 18 Oct 2025 19:35:40 +0200
Subject: [PATCH] tests/functional2: migrate eval.sh

Change-Id: Ib5fb9e3b5d76612e7259ec17fb890298198fc885
---
 tests/functional/eval.sh                |  66 -----------
 tests/functional/meson.build            |   1 -
 tests/functional2/eval/assets/eval.nix  |   5 +
 tests/functional2/eval/test_eval_cli.py | 144 ++++++++++++++++++++++++
 4 files changed, 149 insertions(+), 67 deletions(-)
 delete mode 100644 tests/functional/eval.sh
 create mode 100644 tests/functional2/eval/assets/eval.nix
 create mode 100644 tests/functional2/eval/test_eval_cli.py

diff --git a/tests/functional/eval.sh b/tests/functional/eval.sh
deleted file mode 100644
index 0834efbf4..000000000
--- a/tests/functional/eval.sh
+++ /dev/null
@@ -1,66 +0,0 @@
-source common.sh
-
-clearStore
-
-testStdinHeredoc=$(nix eval -f - <<EOF
-{
-  bar = 3 + 1;
-  foo = 2 + 2;
-}
-EOF
-)
-[[ $testStdinHeredoc == '{ bar = 4; foo = 4; }' ]]
-
-nix eval --expr 'assert 1 + 2 == 3; true'
-nix eval -E 'assert 1 + 2 == 3; true'
-
-[[ $(nix eval int -f "./eval.nix") == 123 ]]
-[[ $(nix eval str -f "./eval.nix") == '"foo\nbar"' ]]
-[[ $(nix eval str --raw -f "./eval.nix") == $'foo\nbar' ]]
-[[ "$(nix eval attr -f "./eval.nix")" == '{ foo = "bar"; }' ]]
-[[ $(nix eval attr --json -f "./eval.nix") == '{"foo":"bar"}' ]]
-[[ $(nix eval int -f - < "./eval.nix") == 123 ]]
-[[ "$(nix eval --expr '{"assert"=1;bar=2;}')" == '{ "assert" = 1; bar = 2; }' ]]
-
-# Non-coercible values throws errors under `--raw`
-topLevelInteger="$(expectStderr 1 nix eval int --raw -f "./eval.nix")"
-[[ "$topLevelInteger" =~ "error: cannot coerce an integer to a string: 123" ]]
-
-# Top-level eval errors should be printed to stderr with a traceback.
-topLevelThrow="$(expectStderr 1 nix eval --expr 'throw "a sample throw message"')"
-[[ "$topLevelThrow" =~ "a sample throw message" ]]
-[[ "$topLevelThrow" =~ "caused by explicit throw" ]]
-
-# But errors inside something should print an elided version, and exit with 0.
-outputOfNestedThrow="$(nix eval --expr '{ throws = throw "a sample throw message"; }')"
-[[ "${outputOfNestedThrow}" == "{ throws = «error: a sample throw message»; }" ]]
-
-# Check if toFile can be utilized during restricted eval
-[[ $(nix eval --restrict-eval --expr 'import (builtins.toFile "source" "42")') == 42 ]]
-
-nix-instantiate --eval -E 'assert 1 + 2 == 3; true'
-[[ $(nix-instantiate -A int --eval "./eval.nix") == 123 ]]
-[[ $(nix-instantiate -A str --eval "./eval.nix") == '"foo\nbar"' ]]
-[[ $(nix-instantiate -A str --raw --eval "./eval.nix") == $'foo\nbar' ]]
-[[ "$(nix-instantiate -A attr --eval "./eval.nix")" == '{ foo = "bar"; }' ]]
-[[ $(nix-instantiate -A attr --eval --json "./eval.nix") == '{"foo":"bar"}' ]]
-[[ $(nix-instantiate -A int --eval - < "./eval.nix") == 123 ]]
-[[ "$(nix-instantiate --eval -E '{"assert"=1;bar=2;}')" == '{ "assert" = 1; bar = 2; }' ]]
-
-# Non-coercible values throws errors under `--raw`
-topLevelInteger="$(expectStderr 1 nix-instantiate -A int --raw "./eval.nix")"
-[[ "$topLevelInteger" =~ "error: expression was expected to be a derivation or collection of derivations, but instead was an integer" ]]
-
-# Check that symlink cycles don't cause a hang.
-ln -sfn cycle.nix $TEST_ROOT/cycle.nix
-(! nix eval --file $TEST_ROOT/cycle.nix)
-
-# Check that relative symlinks are resolved correctly.
-mkdir -p $TEST_ROOT/xyzzy $TEST_ROOT/foo
-ln -sfn ../xyzzy $TEST_ROOT/foo/bar
-printf 123 > $TEST_ROOT/xyzzy/default.nix
-[[ $(nix eval --impure --expr "import $TEST_ROOT/foo/bar") = 123 ]]
-
-# Test that unknown settings are warned about
-out="$(expectStderr 0 nix eval --option foobar baz --expr '""' --raw)"
-[[ "$(echo "$out" | grep foobar | wc -l)" = 1 ]]
diff --git a/tests/functional/meson.build b/tests/functional/meson.build
index 3addb04fe..4fbff5adc 100644
--- a/tests/functional/meson.build
+++ b/tests/functional/meson.build
@@ -108,7 +108,6 @@ functional_tests_scripts = [
   'build-jobless.sh',
   'nar-access.sh',
   'impure-eval.sh',
-  'eval.sh',
   'repl.sh',
   'binary-cache-build-remote.sh',
   'logging.sh',
diff --git a/tests/functional2/eval/assets/eval.nix b/tests/functional2/eval/assets/eval.nix
new file mode 100644
index 000000000..cabf28c29
--- /dev/null
+++ b/tests/functional2/eval/assets/eval.nix
@@ -0,0 +1,5 @@
+{
+  int = 123;
+  str = "foo\nbar";
+  attr.foo = "bar";
+}
diff --git a/tests/functional2/eval/test_eval_cli.py b/tests/functional2/eval/test_eval_cli.py
new file mode 100644
index 000000000..a00fbb977
--- /dev/null
+++ b/tests/functional2/eval/test_eval_cli.py
@@ -0,0 +1,144 @@
+from pathlib import Path
+from typing import Any
+
+import pytest
+
+from functional2.testlib.fixtures.file_helper import with_files, CopyFile, Symlink, File
+from functional2.testlib.fixtures.nix import Nix
+
+
+@pytest.fixture(autouse=True)
+def nix_command_feature(nix: Nix):
+    nix.settings.feature("nix-command")
+
+
+@pytest.mark.parametrize(
+    ("stdin", "exp", "flags"),
+    [
+        (
+            b"""
+                {
+                    bar = 3 + 1;
+                    foo = 2 + 2;
+                }
+            """,
+            "{ bar = 4; foo = 4; }",
+            ["-f", "-"],
+        )
+    ],
+)
+@with_files({"eval.nix": CopyFile("assets/eval.nix")})
+def test_valid_eval_stdin(nix: Nix, stdin: bytes, exp: Any, flags: list[str]):
+    cmd = nix.nix(["eval", *flags]).with_stdin(stdin)
+    res = cmd.run().ok()
+    assert res.stdout_plain == exp
+
+
+@with_files({"eval.nix": CopyFile("assets/eval.nix")})
+def test_valid_filename_stdin(nix: Nix, files: Path):
+    stdin = (files / "eval.nix").read_bytes()
+    res = nix.nix(["eval", "int", "-f", "-"]).with_stdin(stdin).run().ok()
+    assert res.stdout_plain == "123"
+
+    res = nix.nix_instantiate(["-A", "int", "--eval", "-"]).with_stdin(stdin).run().ok()
+    assert res.stdout_plain == "123"
+
+
+@pytest.mark.parametrize(
+    ("flags", "exp"),
+    [
+        (["int"], "123"),
+        (["str"], '"foo\\nbar"'),
+        (["str", "--raw"], "foo\nbar"),
+        (["attr"], '{ foo = "bar"; }'),
+        (["attr", "--json"], '{"foo":"bar"}'),
+    ],
+)
+@with_files({"eval.nix": CopyFile("assets/eval.nix")})
+def test_valid_eval_f(nix: Nix, flags: list[str], exp: str):
+    # nix3 cli
+    res = nix.nix(["eval", *flags, "-f", "./eval.nix"]).run().ok()
+    assert res.stdout_plain == exp
+
+    # legacy cli
+    res = nix.nix_instantiate(["-A", *flags, "--eval", "./eval.nix"]).run().ok()
+    assert res.stdout_plain == exp
+
+
+@pytest.mark.parametrize(
+    ("expr", "exp"),
+    [("assert 1 + 2 == 3; true", "true"), ('{"assert"=1;bar=2;}', '{ "assert" = 1; bar = 2; }')],
+)
+@pytest.mark.parametrize("long", [False, True])
+def test_valid_expr(nix: Nix, expr: str, exp: str, long: bool):
+    flag = "--expr" if long else "-E"
+    res = nix.nix(["eval", flag, expr]).run().ok()
+    assert res.stdout_plain == exp
+
+    res = nix.nix_instantiate(["--eval", flag, expr]).run().ok()
+    assert res.stdout_plain == exp
+
+
+@with_files({"eval.nix": CopyFile("assets/eval.nix")})
+def test_invalid_no_coercible_values(nix: Nix):
+    """Non-coercible values throws errors under `--raw`"""
+    res = nix.nix(["eval", "int", "--raw", "-f", "./eval.nix"]).run().expect(1)
+    assert "error: cannot coerce an integer to a string: 123" in res.stderr_plain
+
+    res = nix.nix_instantiate(["-A", "int", "--raw", "./eval.nix"]).run().expect(1)
+    assert (
+        "error: expression was expected to be a derivation or collection of derivations, but instead was an integer"
+        in res.stderr_plain
+    )
+
+
+def test_invalid_top_level_error(nix: Nix):
+    """Top-level eval errors should be printed to stderr with a traceback."""
+    res = nix.nix(["eval", "--expr", 'throw "a sample throw message"']).run().expect(1)
+    assert "a sample throw message" in res.stderr_plain
+    assert "caused by explicit throw" in res.stderr_plain
+
+
+def test_valid_nested_error(nix: Nix):
+    """But errors inside something should print an elided version, and exit with 0."""
+    res = nix.nix(["eval", "--expr", '{ throws = throw "a sample throw message"; }']).run().ok()
+    assert res.stdout_plain == "{ throws = «error: a sample throw message»; }"
+
+
+def test_valid_restricted_toFile(nix: Nix):  # noqa: N802 # builtin name
+    """Check if toFile can be utilized during restricted eval"""
+    res = (
+        nix.nix(["eval", "--restrict-eval", "--expr", 'import (builtins.toFile "source" "42")'])
+        .run()
+        .ok()
+    )
+    assert res.stdout_plain == "42"
+
+
+@with_files({"cycle.nix": Symlink("cycle.nix")})
+# timeout given in seconds
+@pytest.mark.timeout(1)
+def test_invalid_no_hang_symlink_cycle(nix: Nix):
+    """Check that symlink cycles don't cause a hang."""
+    res = nix.nix(["eval", "--file", "cycle.nix"]).run().expect(1)
+    assert (
+        "error: too many symbolic links encountered while traversing the path" in res.stderr_plain
+    )
+
+
+@with_files({"xyzzy": {"default.nix": File("123")}, "foo": {"bar": Symlink("../xyzzy")}})
+def test_valid_symlink_resolution(nix: Nix):
+    """Check that relative symlinks are resolved correctly."""
+    res = nix.nix(["eval", "--impure", "--expr", "import ./foo/bar"]).run().ok()
+    assert res.stdout_plain == "123"
+
+
+def test_valid_warn_unknown_setting(nix: Nix):
+    """Test that unknown settings are warned about"""
+    res = (
+        nix.nix(["eval", "--option", "foobar", "baz", "--expr", '"foxes are cute"', "--raw"])
+        .run()
+        .ok()
+    )
+    assert res.stdout_plain == "foxes are cute"
+    assert "warning: unknown setting 'foobar'" in res.stderr_plain