From b23ff6fc68e66881e371b50dce587753302cdca8 Mon Sep 17 00:00:00 2001
From: Leonard Cohnen <leonard.cohnen@gmail.com>
Date: Wed, 12 Mar 2025 20:11:22 +0100
Subject: [PATCH] genpolicy: refactor policy test workdir setup

This aligns the workdir preparation more closely with the workdir
preparation for the generate integration test. Most notably, we
clean up the temporary directory before we execute the tests in it.
This way we better isolate different runs.

Signed-off-by: Leonard Cohnen <leonard.cohnen@gmail.com>
Signed-off-by: Markus Rudy <mr@edgeless.systems>
---
 src/tools/genpolicy/tests/policy/main.rs | 63 +++++++++++++++++-------
 1 file changed, 46 insertions(+), 17 deletions(-)

diff --git a/src/tools/genpolicy/tests/policy/main.rs b/src/tools/genpolicy/tests/policy/main.rs
index 8454ade8ed..be89899bb4 100644
--- a/src/tools/genpolicy/tests/policy/main.rs
+++ b/src/tools/genpolicy/tests/policy/main.rs
@@ -5,6 +5,7 @@
 
 #[cfg(test)]
 mod tests {
+    use anyhow::Context;
     use base64::prelude::*;
     use std::fmt::{self, Display};
     use std::fs::{self, File};
@@ -63,23 +64,7 @@ mod tests {
     /// with the tag `type` listing the exact type of request.
     async fn runtests(test_case_dir: &str) {
         // Prepare temp dir for running genpolicy.
-        let workdir = path::PathBuf::from(env!("CARGO_TARGET_TMPDIR")).join(test_case_dir);
-        fs::create_dir_all(&workdir)
-            .expect("should be able to create directories under CARGO_TARGET_TMPDIR");
-
-        let testdata_dir = path::PathBuf::from(env!("CARGO_MANIFEST_DIR"))
-            .join("tests/policy/testdata")
-            .join(test_case_dir);
-        fs::copy(testdata_dir.join("pod.yaml"), workdir.join("pod.yaml"))
-            .expect("copying files around should not fail");
-
-        let genpolicy_dir =
-            path::PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("../../tools/genpolicy");
-
-        for base in ["rules.rego", "genpolicy-settings.json"] {
-            fs::copy(genpolicy_dir.join(base), workdir.join(base))
-                .expect("copying files around should not fail");
-        }
+        let (workdir, testdata_dir) = prepare_workdir(test_case_dir, &["pod.yaml"]);
 
         // Run the command and return the generated policy.
 
@@ -153,6 +138,50 @@ mod tests {
         }
     }
 
+    fn prepare_workdir(
+        test_case_dir: &str,
+        files_to_copy: &[&str],
+    ) -> (path::PathBuf, path::PathBuf) {
+        // Prepare temp dir for running genpolicy.
+        let workdir = path::PathBuf::from(env!("CARGO_TARGET_TMPDIR")).join(test_case_dir);
+        fs::create_dir_all(&workdir)
+            .expect("should be able to create directories under CARGO_TARGET_TMPDIR");
+
+        let testdata_dir = path::PathBuf::from(env!("CARGO_MANIFEST_DIR"))
+            .join("tests/policy/testdata")
+            .join(test_case_dir);
+
+        // Make sure that workdir is empty.
+        for entry in fs::read_dir(&workdir).expect("should be able to read directories") {
+            let entry = entry.expect("should be able to read directory entries");
+            fs::remove_file(entry.path()).expect("should be able to remove files");
+        }
+
+        for file in files_to_copy {
+            fs::copy(testdata_dir.join(file), workdir.join(file))
+                .context(format!(
+                    "{:?} --> {:?}",
+                    testdata_dir.join(file),
+                    workdir.join(file)
+                ))
+                .expect("copying files around should not fail");
+        }
+
+        let genpolicy_dir = path::PathBuf::from(env!("CARGO_MANIFEST_DIR"));
+
+        for base in ["rules.rego", "genpolicy-settings.json"] {
+            fs::copy(genpolicy_dir.join(base), workdir.join(base))
+                .context(format!(
+                    "{:?} --> {:?}",
+                    genpolicy_dir.join(base),
+                    workdir.join(base)
+                ))
+                .expect("copying files around should not fail");
+        }
+
+        (workdir, testdata_dir)
+    }
+
     #[tokio::test]
     async fn test_copyfile() {
         runtests("copyfile").await;