feat(tests): e2e supergraph fetch

tests/e2e/supergraph/fetch.rs

@@ -0,0 +1,49 @@
+use std::fs::read_to_string;
+use std::process::Command;
+
+use assert_cmd::prelude::CommandCargoExt;
+use httpmock::Regex;
+use rstest::rstest;
+use tempfile::Builder;
+use tracing::error;
+use tracing_test::traced_test;
+
+use crate::e2e::remote_supergraph_graphref;
+
+#[rstest]
+#[ignore]
+#[tokio::test(flavor = "multi_thread")]
+#[traced_test]
+async fn e2e_test_rover_supergraph_fetch(remote_supergraph_graphref: String) {
+    // GIVEN
+    //   - supergraph fetch with a file output
+    let out_file = Builder::new()
+        .suffix(".graphql")
+        .tempfile()
+        .expect("Could not create output file");
+
+    // WHEN
+    //   - invoked
+    let mut cmd = Command::cargo_bin("rover").expect("Could not find necessary binary");
+    cmd.args([
+        "supergraph",
+        "fetch",
+        "--output",
+        out_file.path().to_str().unwrap(),
+        &remote_supergraph_graphref,
+    ]);
+
+    // THEN
+    //   -  successfull command; no panics, stderr messages
+    //   - the Query type exists, meaning that a schema was properly fetched
+    let output = cmd.output().expect("Could not run command");
+    if !output.status.success() {
+        error!("{}", String::from_utf8(output.stderr).unwrap());
+        panic!("Command did not complete successfully");
+    }
+    let fetched_schema = read_to_string(out_file.path()).expect("Could not read output file");
+    let re = Regex::new("query: Query").unwrap();
+    let query_type_found = re.is_match(&fetched_schema);
+
+    assert!(query_type_found);
+}

tests/e2e/supergraph/mod.rs

@@ -1 +1,2 @@
 mod compose;
+mod fetch;