Test from_filename with new harness

dotenv/tests/integration/api/from_filename.rs

@@ -1 +1,112 @@
+use crate::util::*;
+use dotenvy::from_filename;
+use dotenvy_test_util::*;
 
+#[test]
+fn no_file() {
+    let testenv = TestEnv::init();
+    test_in_env(&testenv, || {
+        let err = from_filename("nonexistent.env").unwrap_err();
+        assert_err_not_found(err);
+    });
+}
+
+#[test]
+fn empty_default_file() {
+    let testenv = TestEnv::init_with_envfile("");
+    test_in_env(&testenv, || {
+        assert!(from_filename(".env").is_ok());
+    });
+}
+
+#[test]
+fn empty_custom_file() {
+    let mut testenv = TestEnv::init();
+    testenv.add_envfile(".custom.env", "");
+    test_in_env(&testenv, || {
+        assert!(from_filename(".custom.env").is_ok());
+    });
+}
+
+#[test]
+fn default_file_not_read_on_missing_file() {
+    test_in_default_env(|| {
+        let err = from_filename("nonexistent.env").unwrap_err();
+        assert_err_not_found(err);
+        assert_env_var_unset(DEFAULT_TEST_KEY);
+    })
+}
+
+#[test]
+fn dotenv_then_custom() {
+    let mut testenv = TestEnv::default();
+    testenv.add_envfile("custom", KEYVAL_1);
+    test_in_env(&testenv, || {
+        dotenvy::dotenv().unwrap();
+        from_filename("custom").unwrap();
+        assert_env_var(KEY_1, VAL_1);
+        assert_default_keys();
+    });
+}
+
+#[test]
+fn dotenv_then_custom_no_override() {
+    let mut testenv = TestEnv::default();
+    testenv.add_envfile("custom", format!("{DEFAULT_TEST_KEY}=from_custom"));
+    test_in_env(&testenv, || {
+        dotenvy::dotenv().unwrap();
+        from_filename("custom").unwrap();
+        assert_default_keys();
+    });
+}
+
+#[test]
+fn explicit_no_override() {
+    let mut testenv = TestEnv::init();
+    testenv.add_env_var(KEY_1, VAL_1);
+    testenv.add_envfile("custom", format!("{KEY_1}=from_custom"));
+    test_in_env(&testenv, || {
+        from_filename("custom").unwrap();
+        assert_env_var(KEY_1, VAL_1);
+    });
+}
+
+#[test]
+fn child_dir() {
+    let mut testenv = TestEnv::init();
+    testenv.add_child_dir("child");
+    testenv.add_envfile("child/custom", KEYVAL_1);
+    test_in_env(&testenv, || {
+        from_filename("child/custom").unwrap();
+        assert_env_var(KEY_1, VAL_1);
+    });
+}
+
+#[test]
+fn parent_dir_relative_path() {
+    let mut testenv = TestEnv::init();
+    testenv.add_child_dir("child");
+    testenv.add_envfile("custom.env", KEYVAL_1);
+    testenv.set_work_dir("child");
+    test_in_env(&testenv, || {
+        from_filename("../custom.env").unwrap();
+        assert_env_var(KEY_1, VAL_1);
+    });
+}
+
+#[test]
+fn parent_dir_absolute_path() {
+    let mut testenv = TestEnv::init();
+    testenv.add_child_dir("child");
+    testenv.add_envfile("custom.env", KEYVAL_1);
+    testenv.set_work_dir("child");
+    test_in_env(&testenv, || {
+        let path = testenv
+            .temp_path()
+            .join("custom.env")
+            .canonicalize()
+            .expect("canonicalize envfile");
+        from_filename(path).unwrap();
+        assert_env_var(KEY_1, VAL_1);
+    });
+}