fix: leverage find_resource! macro in load_sse_fixture_with_id (#8888)

This helps prepare us for Bazel builds:
https://github.com/openai/codex/pull/8875.

codex-rs/core/tests/common/lib.rs

@@ -1,5 +1,6 @@
 #![expect(clippy::expect_used)]
 
+use codex_utils_cargo_bin::find_resource;
 use tempfile::TempDir;
 
 use codex_core::CodexThread;
@@ -150,7 +151,16 @@ pub fn load_sse_fixture_with_id_from_str(raw: &str, id: &str) -> String {
 /// single JSON template be reused by multiple tests that each need a unique
 /// `response_id`.
 pub fn load_sse_fixture_with_id(path: impl AsRef<std::path::Path>, id: &str) -> String {
-    let raw = std::fs::read_to_string(path).expect("read fixture template");
+    let p = path.as_ref();
+    let full_path = match find_resource!(p) {
+        Ok(p) => p,
+        Err(err) => panic!(
+            "failed to find fixture template at {:?}: {err}",
+            path.as_ref()
+        ),
+    };
+
+    let raw = std::fs::read_to_string(full_path).expect("read fixture template");
     let replaced = raw.replace("__ID__", id);
     let events: Vec<serde_json::Value> =
         serde_json::from_str(&replaced).expect("parse JSON fixture");

codex-rs/core/tests/suite/client.rs

@@ -58,7 +58,7 @@ use wiremock::matchers::query_param;
 
 /// Build minimal SSE stream with completed marker using the JSON fixture.
 fn sse_completed(id: &str) -> String {
-    load_sse_fixture_with_id("tests/fixtures/completed_template.json", id)
+    load_sse_fixture_with_id("../fixtures/completed_template.json", id)
 }
 
 #[expect(clippy::unwrap_used)]

codex-rs/core/tests/suite/fork_thread.rs

@@ -22,7 +22,7 @@ use wiremock::matchers::path;
 
 /// Build minimal SSE stream with completed marker using the JSON fixture.
 fn sse_completed(id: &str) -> String {
-    core_test_support::load_sse_fixture_with_id("tests/fixtures/completed_template.json", id)
+    core_test_support::load_sse_fixture_with_id("../fixtures/completed_template.json", id)
 }
 
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]

codex-rs/core/tests/suite/model_tools.rs

@@ -7,7 +7,7 @@ use core_test_support::skip_if_no_network;
 use core_test_support::test_codex::test_codex;
 
 fn sse_completed(id: &str) -> String {
-    load_sse_fixture_with_id("tests/fixtures/completed_template.json", id)
+    load_sse_fixture_with_id("../fixtures/completed_template.json", id)
 }
 
 #[allow(clippy::expect_used)]

codex-rs/core/tests/suite/prompt_caching.rs

@@ -44,7 +44,7 @@ fn default_env_context_str(cwd: &str, shell: &Shell) -> String {
 
 /// Build minimal SSE stream with completed marker using the JSON fixture.
 fn sse_completed(id: &str) -> String {
-    load_sse_fixture_with_id("tests/fixtures/completed_template.json", id)
+    load_sse_fixture_with_id("../fixtures/completed_template.json", id)
 }
 
 fn assert_tool_names(body: &serde_json::Value, expected_names: &[&str]) {

codex-rs/core/tests/suite/stream_error_allows_next_turn.rs

@@ -16,7 +16,7 @@ use wiremock::matchers::method;
 use wiremock::matchers::path;
 
 fn sse_completed(id: &str) -> String {
-    load_sse_fixture_with_id("tests/fixtures/completed_template.json", id)
+    load_sse_fixture_with_id("../fixtures/completed_template.json", id)
 }
 
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]

codex-rs/core/tests/suite/stream_no_completed.rs

@@ -25,7 +25,7 @@ fn sse_incomplete() -> String {
 }
 
 fn sse_completed(id: &str) -> String {
-    load_sse_fixture_with_id("tests/fixtures/completed_template.json", id)
+    load_sse_fixture_with_id("../fixtures/completed_template.json", id)
 }
 
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]

codex-rs/core/tests/suite/web_search_cached.rs

@@ -10,7 +10,7 @@ use pretty_assertions::assert_eq;
 use serde_json::Value;
 
 fn sse_completed(id: &str) -> String {
-    load_sse_fixture_with_id("tests/fixtures/completed_template.json", id)
+    load_sse_fixture_with_id("../fixtures/completed_template.json", id)
 }
 
 #[allow(clippy::expect_used)]