feat: add more headers unit tests

Author: dancixx

tests/snippet_tests/mod.rs

@@ -1,6 +1,7 @@
 mod test_batch_update;
 mod test_clear_payload;
 mod test_collection_exists;
+mod test_config_headers;
 mod test_count_points;
 mod test_create_collection;
 mod test_create_collection_with_bq;

tests/snippet_tests/test_config_headers.rs

@@ -0,0 +1,74 @@
+use qdrant_client::config::{CompressionEncoding, QdrantConfig};
+
+#[test]
+fn header_adds_single_header() {
+    let config = QdrantConfig::from_url("http://localhost:6334").header("x-custom-id", "my-client");
+
+    assert_eq!(
+        config.custom_headers,
+        vec![("x-custom-id".to_string(), "my-client".to_string())]
+    );
+}
+
+#[test]
+fn header_chain_preserves_order() {
+    let config = QdrantConfig::from_url("http://localhost:6334")
+        .header("x-a", "1")
+        .header("x-b", "2")
+        .header("x-a", "3");
+
+    assert_eq!(
+        config.custom_headers,
+        vec![
+            ("x-a".to_string(), "1".to_string()),
+            ("x-b".to_string(), "2".to_string()),
+            ("x-a".to_string(), "3".to_string()),
+        ]
+    );
+}
+
+#[test]
+fn header_allows_duplicate_keys() {
+    let config = QdrantConfig::from_url("http://localhost:6334")
+        .header("openai-api-key", "k1")
+        .header("openai-api-key", "k2");
+
+    assert_eq!(config.custom_headers.len(), 2);
+    assert_eq!(
+        config.custom_headers,
+        vec![
+            ("openai-api-key".to_string(), "k1".to_string()),
+            ("openai-api-key".to_string(), "k2".to_string()),
+        ]
+    );
+}
+
+#[test]
+fn header_does_not_mutate_other_config() {
+    let base = QdrantConfig::from_url("http://localhost:6334")
+        .api_key("secret")
+        .timeout(10u64)
+        .connect_timeout(20u64)
+        .compression(Some(CompressionEncoding::Gzip))
+        .skip_compatibility_check();
+
+    let with_header = base.clone().header("x-feature", "on");
+
+    assert_eq!(with_header.uri, base.uri);
+    assert_eq!(with_header.timeout, base.timeout);
+    assert_eq!(with_header.connect_timeout, base.connect_timeout);
+    assert_eq!(
+        with_header.keep_alive_while_idle,
+        base.keep_alive_while_idle
+    );
+    assert_eq!(with_header.api_key, base.api_key);
+    assert_eq!(with_header.compression, base.compression);
+    assert_eq!(with_header.check_compatibility, base.check_compatibility);
+    assert_eq!(with_header.pool_size, base.pool_size);
+
+    assert_eq!(
+        with_header.custom_headers,
+        vec![("x-feature".to_string(), "on".to_string())]
+    );
+    assert!(base.custom_headers.is_empty());
+}