Wrote sample integration test and added missing "use" statements

Author: Azrenbeth

.gitignore

@@ -3,4 +3,5 @@
 *.data
 *.old
 out.sql
-*.csv
+*.csv
+/tests/tmp/**

Cargo.lock

@@ -15,6 +15,7 @@ postgres-openssl = "0.5.0"
 rand = "0.8.0"
 rayon = "1.3.0"
 string_cache = "0.8.0"
+serial_test = "0.5.1"
 
 [dependencies.state-map]
 git = "https://github.com/matrix-org/rust-matrix-state-map"

Cargo.toml

@@ -1,9 +1,10 @@
 use openssl::ssl::{SslConnector, SslMethod, SslVerifyMode};
 use postgres::Client;
 use postgres_openssl::MakeTlsConnector;
-use std::collections::BTreeMap;
+use rand::{distributions::Alphanumeric, thread_rng, Rng};
+use std::{borrow::Cow, collections::BTreeMap, fmt};
 
-use synapse_compress_state::{PGEscape, StateGroupEntry};
+use synapse_compress_state::StateGroupEntry;
 
 static DB_URL: &str = "postgresql://synapse_user:synapse_pass@localhost/synapse";
 
@@ -14,7 +15,7 @@ pub fn add_contents_to_database(room_id: &str, state_group_map: &BTreeMap<i64, S
     let connector = MakeTlsConnector::new(builder.build());
 
     let mut client = Client::connect(DB_URL, connector).unwrap();
-    
+
     // build up the query
     let mut sql = "".to_string();
 
@@ -97,4 +98,4 @@ impl<'a> fmt::Display for PGEscape<'a> {
 
         write!(f, "{}{}{}", delim, self.0, delim)
     }
-}
+}

tests/common/mod.rs

@@ -0,0 +1,64 @@
+use std::collections::BTreeMap;
+
+use serial_test::serial;
+use state_map::StateMap;
+use synapse_compress_state::{run, Config, StateGroupEntry};
+
+mod common;
+
+#[test]
+#[serial(db)]
+fn run_succeeds_without_crashing() {
+    let mut initial: BTreeMap<i64, StateGroupEntry> = BTreeMap::new();
+    let mut prev = None;
+
+    // This starts with the following structure
+    //
+    // 0-1-2-3-4-5-6-7-8-9-10-11-12-13
+    //
+    // Each group i has state:
+    //     ('node','is',      i)
+    //     ('group',  j, 'seen') - for all j less than i
+    for i in 0i64..=13i64 {
+        let mut entry = StateGroupEntry {
+            in_range: true,
+            prev_state_group: prev,
+            state_map: StateMap::new(),
+        };
+        entry
+            .state_map
+            .insert("group", &i.to_string(), "seen".into());
+        entry.state_map.insert("node", "is", i.to_string().into());
+
+        initial.insert(i, entry);
+
+        prev = Some(i)
+    }
+
+    common::empty_database();
+    common::add_contents_to_database("room1", &initial);
+
+    let db_url = "postgresql://synapse_user:synapse_pass@localhost/synapse".to_string();
+    let output_file = "./tests/tmp/output.sql".to_string();
+    let room_id = "room1".to_string();
+    let min_state_group = "".to_string();
+    let min_saved_rows = "".to_string();
+    let groups_to_compress = "".to_string();
+    let level_sizes = "3,3".to_string();
+    let transactions = true;
+    let graphs = false;
+
+    let config = Config::new(
+        db_url.clone(),
+        output_file,
+        room_id.clone(),
+        min_state_group,
+        groups_to_compress,
+        min_saved_rows,
+        level_sizes,
+        transactions,
+        graphs,
+    );
+
+    run(config);
+}