Add tests, use tarpaulin

.gitignore

@@ -2,3 +2,4 @@
 **/*.rs.bk
 bunbun.toml
 out
+tarpaulin-report.html

code_coverage

@@ -0,0 +1,11 @@
+#!/usr/bin/env bash
+
+set -euxo pipefail
+
+if ! cargo tarpaulin -h &> /dev/null; then
+  echo "Tarpaulin not installed, automatically installing in 3 seconds.";
+  sleep 3;
+  cargo install cargo-tarpaulin;
+fi;
+
+cargo tarpaulin -o html && xdg-open "tarpaulin-report.html"

src/config.rs

@@ -14,6 +14,10 @@ use std::str::FromStr;
 
 const CONFIG_FILENAME: &str = "bunbun.yaml";
 const DEFAULT_CONFIG: &[u8] = include_bytes!("../bunbun.default.yaml");
+#[cfg(not(test))]
+const LARGE_FILE_SIZE_THRESHOLD: u64 = 100_000_000;
+#[cfg(test)]
+const LARGE_FILE_SIZE_THRESHOLD: u64 = 1_000_000;
 
 #[derive(Deserialize, Debug, PartialEq)]
 pub struct Config {
@@ -307,7 +311,7 @@ pub fn read_config(
   let file_size = config_file.metadata()?.len();
 
   // 100 MB
-  if file_size > 100_000_000 && !large_config {
+  if file_size > LARGE_FILE_SIZE_THRESHOLD && !large_config {
     return Err(BunBunError::ConfigTooLarge(file_size));
   }
 
@@ -377,3 +381,38 @@ mod route {
     );
   }
 }
+
+#[cfg(test)]
+mod read_config {
+  use super::*;
+
+  #[test]
+  fn empty_file() {
+    let config_file = tempfile::tempfile().unwrap();
+    assert!(matches!(
+      read_config(config_file, false),
+      Err(BunBunError::ZeroByteConfig)
+    ));
+  }
+
+  #[test]
+  fn config_too_large() {
+    let mut config_file = tempfile::tempfile().unwrap();
+    let size_to_write = (LARGE_FILE_SIZE_THRESHOLD + 1) as usize;
+    config_file.write(&[0].repeat(size_to_write)).unwrap();
+    match read_config(config_file, false) {
+      Err(BunBunError::ConfigTooLarge(size))
+        if size as usize == size_to_write => {}
+      Err(BunBunError::ConfigTooLarge(size)) => {
+        panic!("Mismatched size: {} != {}", size, size_to_write)
+      }
+      res => panic!("Wrong result, got {:#?}", res),
+    }
+  }
+
+  #[test]
+  fn valid_config() {
+    let config_file = File::open("bunbun.default.yaml").unwrap();
+    assert!(read_config(config_file, false).is_ok());
+  }
+}

src/main.rs

@@ -23,8 +23,10 @@ use std::time::Duration;
 
 mod cli;
 mod config;
+#[cfg(not(tarpaulin_include))]
 mod error;
 mod routes;
+#[cfg(not(tarpaulin_include))]
 mod template_args;
 
 /// Dynamic variables that either need to be present at runtime, or can be
@@ -38,6 +40,7 @@ pub struct State {
 }
 
 #[actix_rt::main]
+#[cfg(not(tarpaulin_include))]
 async fn main() {
   std::process::exit(match run().await {
     Ok(_) => 0,
@@ -48,6 +51,7 @@ async fn main() {
   })
 }
 
+#[cfg(not(tarpaulin_include))]
 async fn run() -> Result<(), BunBunError> {
   let opts = cli::Opts::parse();
 
@@ -95,6 +99,7 @@ async fn run() -> Result<(), BunBunError> {
 /// Initializes the logger based on the number of quiet and verbose flags passed
 /// in. Usually, these values are mutually exclusive, that is, if the number of
 /// verbose flags is non-zero then the quiet flag is zero, and vice versa.
+#[cfg(not(tarpaulin_include))]
 fn init_logger(
   num_verbose_flags: u8,
   num_quiet_flags: u8,
@@ -169,6 +174,7 @@ fn compile_templates() -> Result<Handlebars<'static>, TemplateError> {
 ///
 /// This watch object should be kept in scope as dropping it releases all
 /// watches.
+#[cfg(not(tarpaulin_include))]
 fn start_watch(
   state: Arc<RwLock<State>>,
   config_data: ConfigData,