// Copyright 2018-2021 the Deno authors. All rights reserved. MIT license.

use crate::ast::Location;
use crate::colors;
use crate::create_main_worker;
use crate::file_fetcher::File;
use crate::file_watcher;
use crate::file_watcher::ResolutionResult;
use crate::flags::Flags;
use crate::fs_util::collect_specifiers;
use crate::fs_util::is_supported_test_ext;
use crate::fs_util::is_supported_test_path;
use crate::located_script_name;
use crate::module_graph;
use crate::module_graph::GraphBuilder;
use crate::module_graph::Module;
use crate::module_graph::TypeLib;
use crate::ops;
use crate::program_state::ProgramState;
use crate::tokio_util;
use crate::tools::coverage::CoverageCollector;
use crate::FetchHandler;
use deno_ast::swc::common::comments::CommentKind;
use deno_ast::MediaType;
use deno_core::error::generic_error;
use deno_core::error::AnyError;
use deno_core::futures::future;
use deno_core::futures::stream;
use deno_core::futures::FutureExt;
use deno_core::futures::StreamExt;
use deno_core::parking_lot::Mutex;
use deno_core::serde_json::json;
use deno_core::JsRuntime;
use deno_core::ModuleSpecifier;
use deno_runtime::permissions::Permissions;
use log::Level;
use rand::rngs::SmallRng;
use rand::seq::SliceRandom;
use rand::SeedableRng;
use regex::Regex;
use serde::Deserialize;
use std::collections::HashSet;
use std::num::NonZeroUsize;
use std::path::PathBuf;
use std::sync::mpsc::channel;
use std::sync::mpsc::Sender;
use std::sync::Arc;
use std::time::Duration;
use std::time::Instant;
use uuid::Uuid;

/// The test mode is used to determine how a specifier is to be tested.
#[derive(Debug, Clone, PartialEq)]
enum TestMode {
  /// Test as documentation, type-checking fenced code blocks.
  Documentation,
  /// Test as an executable module, loading the module into the isolate and running each test it
  /// defines.
  Executable,
  /// Test as both documentation and an executable module.
  Both,
}

#[derive(Debug, Clone, PartialEq, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct TestDescription {
  pub origin: String,
  pub name: String,
}

#[derive(Debug, Clone, PartialEq, Deserialize)]
#[serde(rename_all = "camelCase")]
pub enum TestOutput {
  // TODO(caspervonb): add stdout and stderr redirection.
  Console(String),
}

#[derive(Debug, Clone, PartialEq, Deserialize)]
#[serde(rename_all = "camelCase")]
pub enum TestResult {
  Ok,
  Ignored,
  Failed(String),
}

#[derive(Debug, Clone, PartialEq, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct TestPlan {
  pub origin: String,
  pub total: usize,
  pub filtered_out: usize,
  pub used_only: bool,
}

#[derive(Debug, Clone, Deserialize)]
#[serde(rename_all = "camelCase")]
pub enum TestEvent {
  Plan(TestPlan),
  Wait(TestDescription),
  Output(TestOutput),
  Result(TestDescription, TestResult, u64),
}

#[derive(Debug, Clone, Deserialize)]
pub struct TestSummary {
  pub total: usize,
  pub passed: usize,
  pub failed: usize,
  pub ignored: usize,
  pub filtered_out: usize,
  pub measured: usize,
  pub failures: Vec<(TestDescription, String)>,
}

impl TestSummary {
  fn new() -> TestSummary {
    TestSummary {
      total: 0,
      passed: 0,
      failed: 0,
      ignored: 0,
      filtered_out: 0,
      measured: 0,
      failures: Vec::new(),
    }
  }

  fn has_failed(&self) -> bool {
    self.failed > 0 || !self.failures.is_empty()
  }

  fn has_pending(&self) -> bool {
    self.total - self.passed - self.failed - self.ignored > 0
  }
}

trait TestReporter {
  fn report_plan(&mut self, plan: &TestPlan);
  fn report_wait(&mut self, description: &TestDescription);
  fn report_output(&mut self, output: &TestOutput);
  fn report_result(
    &mut self,
    description: &TestDescription,
    result: &TestResult,
    elapsed: u64,
  );
  fn report_summary(&mut self, summary: &TestSummary, elapsed: &Duration);
}

struct PrettyTestReporter {
  concurrent: bool,
  echo_output: bool,
}

impl PrettyTestReporter {
  fn new(concurrent: bool, echo_output: bool) -> PrettyTestReporter {
    PrettyTestReporter {
      concurrent,
      echo_output,
    }
  }
}

impl TestReporter for PrettyTestReporter {
  fn report_plan(&mut self, plan: &TestPlan) {
    let inflection = if plan.total == 1 { "test" } else { "tests" };
    println!("running {} {} from {}", plan.total, inflection, plan.origin);
  }

  fn report_wait(&mut self, description: &TestDescription) {
    if !self.concurrent {
      print!("test {} ...", description.name);
    }
  }

  fn report_output(&mut self, output: &TestOutput) {
    if self.echo_output {
      match output {
        TestOutput::Console(line) => println!("{}", line),
      }
    }
  }

  fn report_result(
    &mut self,
    description: &TestDescription,
    result: &TestResult,
    elapsed: u64,
  ) {
    if self.concurrent {
      print!("test {} ...", description.name);
    }

    let status = match result {
      TestResult::Ok => colors::green("ok").to_string(),
      TestResult::Ignored => colors::yellow("ignored").to_string(),
      TestResult::Failed(_) => colors::red("FAILED").to_string(),
    };

    println!(
      " {} {}",
      status,
      colors::gray(format!("({}ms)", elapsed)).to_string()
    );
  }

  fn report_summary(&mut self, summary: &TestSummary, elapsed: &Duration) {
    if !summary.failures.is_empty() {
      println!("\nfailures:\n");
      for (description, error) in &summary.failures {
        println!("{}", description.name);
        println!("{}", error);
        println!();
      }

      println!("failures:\n");
      for (description, _) in &summary.failures {
        println!("\t{}", description.name);
      }
    }

    let status = if summary.has_failed() || summary.has_pending() {
      colors::red("FAILED").to_string()
    } else {
      colors::green("ok").to_string()
    };

    println!(
      "\ntest result: {}. {} passed; {} failed; {} ignored; {} measured; {} filtered out {}\n",
      status,
      summary.passed,
      summary.failed,
      summary.ignored,
      summary.measured,
      summary.filtered_out,
      colors::gray(format!("({}ms)", elapsed.as_millis())),
    );
  }
}

fn create_reporter(
  concurrent: bool,
  echo_output: bool,
) -> Box<dyn TestReporter + Send> {
  Box::new(PrettyTestReporter::new(concurrent, echo_output))
}

/// Test a single specifier as documentation containing test programs, an executable test module or
/// both.
async fn test_specifier(
  program_state: Arc<ProgramState>,
  permissions: Permissions,
  specifier: ModuleSpecifier,
  mode: TestMode,
  filter: Option<String>,
  shuffle: Option<u64>,
  channel: Sender<TestEvent>,
) -> Result<(), AnyError> {
  let test_specifier =
    deno_core::resolve_path(&format!("{}$deno$test.js", Uuid::new_v4()))?;

  let mut test_source = String::new();
  if mode != TestMode::Documentation {
    test_source.push_str(&format!("import \"{}\";\n", specifier));
  }

  let test_file = File {
    local: test_specifier.to_file_path().unwrap(),
    maybe_types: None,
    media_type: MediaType::JavaScript,
    source: Arc::new(test_source),
    specifier: test_specifier.clone(),
    maybe_headers: None,
  };

  program_state.file_fetcher.insert_cached(test_file);

  let init_ops = |js_runtime: &mut JsRuntime| {
    ops::testing::init(js_runtime);

    js_runtime
      .op_state()
      .borrow_mut()
      .put::<Sender<TestEvent>>(channel.clone());
  };

  let mut worker = create_main_worker(
    &program_state,
    specifier.clone(),
    permissions,
    Some(&init_ops),
  );

  let mut maybe_coverage_collector = if let Some(ref coverage_dir) =
    program_state.coverage_dir
  {
    let session = worker.create_inspector_session().await;
    let coverage_dir = PathBuf::from(coverage_dir);
    let mut coverage_collector = CoverageCollector::new(coverage_dir, session);
    worker
      .with_event_loop(coverage_collector.start_collecting().boxed_local())
      .await?;

    Some(coverage_collector)
  } else {
    None
  };

  worker.execute_module(&test_specifier).await?;

  worker.js_runtime.execute_script(
    &located_script_name!(),
    "window.dispatchEvent(new Event('load'));",
  )?;

  let test_result = worker.js_runtime.execute_script(
    &located_script_name!(),
    &format!(
      r#"Deno[Deno.internal].runTests({})"#,
      json!({
        "filter": filter,
        "shuffle": shuffle,
      }),
    ),
  )?;

  worker.js_runtime.resolve_value(test_result).await?;

  worker.js_runtime.execute_script(
    &located_script_name!(),
    "window.dispatchEvent(new Event('unload'));",
  )?;

  if let Some(coverage_collector) = maybe_coverage_collector.as_mut() {
    worker
      .with_event_loop(coverage_collector.stop_collecting().boxed_local())
      .await?;
  }

  Ok(())
}

fn extract_files_from_regex_blocks(
  location: &Location,
  source: &str,
  media_type: MediaType,
  blocks_regex: &Regex,
  lines_regex: &Regex,
) -> Result<Vec<File>, AnyError> {
  let files = blocks_regex
    .captures_iter(source)
    .filter_map(|block| {
      let maybe_attributes: Option<Vec<_>> = block
        .get(1)
        .map(|attributes| attributes.as_str().split(' ').collect());

      let file_media_type = if let Some(attributes) = maybe_attributes {
        if attributes.contains(&"ignore") {
          return None;
        }

        match attributes.get(0) {
          Some(&"js") => MediaType::JavaScript,
          Some(&"jsx") => MediaType::Jsx,
          Some(&"ts") => MediaType::TypeScript,
          Some(&"tsx") => MediaType::Tsx,
          Some(&"") => media_type,
          _ => MediaType::Unknown,
        }
      } else {
        media_type
      };

      if file_media_type == MediaType::Unknown {
        return None;
      }

      let line_offset = source[0..block.get(0).unwrap().start()]
        .chars()
        .filter(|c| *c == '\n')
        .count();

      let line_count = block.get(0).unwrap().as_str().split('\n').count();

      let body = block.get(2).unwrap();
      let text = body.as_str();

      // TODO(caspervonb) generate an inline source map
      let mut file_source = String::new();
      for line in lines_regex.captures_iter(text) {
        let text = line.get(1).unwrap();
        file_source.push_str(&format!("{}\n", text.as_str()));
      }

      file_source.push_str("export {};");

      let file_specifier = deno_core::resolve_url_or_path(&format!(
        "{}${}-{}{}",
        location.specifier,
        location.line + line_offset,
        location.line + line_offset + line_count,
        file_media_type.as_ts_extension(),
      ))
      .unwrap();

      Some(File {
        local: file_specifier.to_file_path().unwrap(),
        maybe_types: None,
        media_type: file_media_type,
        source: Arc::new(file_source),
        specifier: file_specifier,
        maybe_headers: None,
      })
    })
    .collect();

  Ok(files)
}

fn extract_files_from_source_comments(
  specifier: &ModuleSpecifier,
  source: Arc<String>,
  media_type: MediaType,
) -> Result<Vec<File>, AnyError> {
  let parsed_source = deno_ast::parse_module(deno_ast::ParseParams {
    specifier: specifier.as_str().to_string(),
    source: deno_ast::SourceTextInfo::new(
      deno_ast::swc::common::BytePos(0),
      source,
    ),
    media_type,
    capture_tokens: false,
    maybe_syntax: None,
  })?;
  let comments = parsed_source.comments().get_vec();
  let blocks_regex = Regex::new(r"```([^\n]*)\n([\S\s]*?)```")?;
  let lines_regex = Regex::new(r"(?:\* ?)(?:\# ?)?(.*)")?;

  let files = comments
    .iter()
    .filter(|comment| {
      if comment.kind != CommentKind::Block || !comment.text.starts_with('*') {
        return false;
      }

      true
    })
    .flat_map(|comment| {
      let location = Location::from_pos(&parsed_source, comment.span.lo);

      extract_files_from_regex_blocks(
        &location,
        &comment.text,
        media_type,
        &blocks_regex,
        &lines_regex,
      )
    })
    .flatten()
    .collect();

  Ok(files)
}

fn extract_files_from_fenced_blocks(
  specifier: &ModuleSpecifier,
  source: &str,
  media_type: MediaType,
) -> Result<Vec<File>, AnyError> {
  let location = Location {
    specifier: specifier.to_string(),
    line: 1,
    col: 0,
  };

  let blocks_regex = Regex::new(r"```([^\n]*)\n([\S\s]*?)```")?;
  let lines_regex = Regex::new(r"(?:\# ?)?(.*)")?;

  extract_files_from_regex_blocks(
    &location,
    source,
    media_type,
    &blocks_regex,
    &lines_regex,
  )
}

async fn fetch_inline_files(
  program_state: Arc<ProgramState>,
  specifiers: Vec<ModuleSpecifier>,
) -> Result<Vec<File>, AnyError> {
  let mut files = Vec::new();
  for specifier in specifiers {
    let mut fetch_permissions = Permissions::allow_all();
    let file = program_state
      .file_fetcher
      .fetch(&specifier, &mut fetch_permissions)
      .await?;

    let inline_files = if file.media_type == MediaType::Unknown {
      extract_files_from_fenced_blocks(
        &file.specifier,
        &file.source,
        file.media_type,
      )
    } else {
      extract_files_from_source_comments(
        &file.specifier,
        file.source.clone(),
        file.media_type,
      )
    };

    files.extend(inline_files?);
  }

  Ok(files)
}

/// Type check a collection of module and document specifiers.
async fn check_specifiers(
  program_state: Arc<ProgramState>,
  permissions: Permissions,
  specifiers: Vec<(ModuleSpecifier, TestMode)>,
  lib: TypeLib,
) -> Result<(), AnyError> {
  let inline_files = fetch_inline_files(
    program_state.clone(),
    specifiers
      .iter()
      .filter_map(|(specifier, mode)| {
        if *mode != TestMode::Executable {
          Some(specifier.clone())
        } else {
          None
        }
      })
      .collect(),
  )
  .await?;

  if !inline_files.is_empty() {
    let specifiers = inline_files
      .iter()
      .map(|file| file.specifier.clone())
      .collect();

    for file in inline_files {
      program_state.file_fetcher.insert_cached(file);
    }

    program_state
      .prepare_module_graph(
        specifiers,
        lib.clone(),
        Permissions::allow_all(),
        permissions.clone(),
        program_state.maybe_import_map.clone(),
      )
      .await?;
  }

  let module_specifiers = specifiers
    .iter()
    .filter_map(|(specifier, mode)| {
      if *mode != TestMode::Documentation {
        Some(specifier.clone())
      } else {
        None
      }
    })
    .collect();

  program_state
    .prepare_module_graph(
      module_specifiers,
      lib,
      Permissions::allow_all(),
      permissions,
      program_state.maybe_import_map.clone(),
    )
    .await?;

  Ok(())
}

/// Test a collection of specifiers with test modes concurrently.
async fn test_specifiers(
  program_state: Arc<ProgramState>,
  permissions: Permissions,
  specifiers_with_mode: Vec<(ModuleSpecifier, TestMode)>,
  fail_fast: Option<NonZeroUsize>,
  filter: Option<String>,
  shuffle: Option<u64>,
  concurrent_jobs: NonZeroUsize,
) -> Result<(), AnyError> {
  let log_level = program_state.flags.log_level;
  let specifiers_with_mode = if let Some(seed) = shuffle {
    let mut rng = SmallRng::seed_from_u64(seed);
    let mut specifiers_with_mode = specifiers_with_mode.clone();
    specifiers_with_mode.sort_by_key(|(specifier, _)| specifier.clone());
    specifiers_with_mode.shuffle(&mut rng);
    specifiers_with_mode
  } else {
    specifiers_with_mode
  };

  let (sender, receiver) = channel::<TestEvent>();

  let join_handles =
    specifiers_with_mode.iter().map(move |(specifier, mode)| {
      let program_state = program_state.clone();
      let permissions = permissions.clone();
      let specifier = specifier.clone();
      let mode = mode.clone();
      let filter = filter.clone();
      let sender = sender.clone();

      tokio::task::spawn_blocking(move || {
        let join_handle = std::thread::spawn(move || {
          let future = test_specifier(
            program_state,
            permissions,
            specifier,
            mode,
            filter,
            shuffle,
            sender,
          );

          tokio_util::run_basic(future)
        });

        join_handle.join().unwrap()
      })
    });

  let join_stream = stream::iter(join_handles)
    .buffer_unordered(concurrent_jobs.get())
    .collect::<Vec<Result<Result<(), AnyError>, tokio::task::JoinError>>>();

  let mut reporter =
    create_reporter(concurrent_jobs.get() > 1, log_level != Some(Level::Error));

  let handler = {
    tokio::task::spawn_blocking(move || {
      let earlier = Instant::now();
      let mut summary = TestSummary::new();
      let mut used_only = false;

      for event in receiver.iter() {
        match event {
          TestEvent::Plan(plan) => {
            summary.total += plan.total;
            summary.filtered_out += plan.filtered_out;

            if plan.used_only {
              used_only = true;
            }

            reporter.report_plan(&plan);
          }

          TestEvent::Wait(description) => {
            reporter.report_wait(&description);
          }

          TestEvent::Output(output) => {
            reporter.report_output(&output);
          }

          TestEvent::Result(description, result, elapsed) => {
            match &result {
              TestResult::Ok => {
                summary.passed += 1;
              }

              TestResult::Ignored => {
                summary.ignored += 1;
              }

              TestResult::Failed(error) => {
                summary.failed += 1;
                summary.failures.push((description.clone(), error.clone()));
              }
            }

            reporter.report_result(&description, &result, elapsed);
          }
        }

        if let Some(x) = fail_fast {
          if summary.failed >= x.get() {
            break;
          }
        }
      }

      let elapsed = Instant::now().duration_since(earlier);
      reporter.report_summary(&summary, &elapsed);

      if used_only {
        return Err(generic_error(
          "Test failed because the \"only\" option was used",
        ));
      }

      if summary.failed > 0 {
        return Err(generic_error("Test failed"));
      }

      Ok(())
    })
  };

  let (join_results, result) = future::join(join_stream, handler).await;

  let mut join_errors = join_results.into_iter().filter_map(|join_result| {
    join_result
      .ok()
      .map(|handle_result| handle_result.err())
      .flatten()
  });

  if let Some(e) = join_errors.next() {
    return Err(e);
  }

  match result {
    Ok(result) => {
      if let Some(err) = result.err() {
        return Err(err);
      }
    }

    Err(err) => {
      return Err(err.into());
    }
  }

  Ok(())
}

/// Collects specifiers marking them with the appropriate test mode while maintaining the natural
/// input order.
///
/// - Specifiers matching the `is_supported_test_ext` predicate are marked as
/// `TestMode::Documentation`.
/// - Specifiers matching the `is_supported_test_path` are marked as `TestMode::Executable`.
/// - Specifiers matching both predicates are marked as `TestMode::Both`
fn collect_specifiers_with_test_mode(
  include: Vec<String>,
  ignore: Vec<PathBuf>,
  include_inline: bool,
) -> Result<Vec<(ModuleSpecifier, TestMode)>, AnyError> {
  let module_specifiers =
    collect_specifiers(include.clone(), &ignore, is_supported_test_path)?;

  if include_inline {
    return collect_specifiers(include, &ignore, is_supported_test_ext).map(
      |specifiers| {
        specifiers
          .into_iter()
          .map(|specifier| {
            let mode = if module_specifiers.contains(&specifier) {
              TestMode::Both
            } else {
              TestMode::Documentation
            };

            (specifier, mode)
          })
          .collect()
      },
    );
  }

  let specifiers_with_mode = module_specifiers
    .into_iter()
    .map(|specifier| (specifier, TestMode::Executable))
    .collect();

  Ok(specifiers_with_mode)
}

/// Collects module and document specifiers with test modes via `collect_specifiers_with_test_mode`
/// which are then pre-fetched and adjusted based on the media type.
///
/// Specifiers that do not have a known media type that can be executed as a module are marked as
/// `TestMode::Documentation`.
async fn fetch_specifiers_with_test_mode(
  program_state: Arc<ProgramState>,
  include: Vec<String>,
  ignore: Vec<PathBuf>,
  include_inline: bool,
) -> Result<Vec<(ModuleSpecifier, TestMode)>, AnyError> {
  let mut specifiers_with_mode =
    collect_specifiers_with_test_mode(include, ignore, include_inline)?;
  for (specifier, mode) in &mut specifiers_with_mode {
    let file = program_state
      .file_fetcher
      .fetch(specifier, &mut Permissions::allow_all())
      .await?;

    if file.media_type == MediaType::Unknown {
      *mode = TestMode::Documentation
    }
  }

  Ok(specifiers_with_mode)
}

#[allow(clippy::too_many_arguments)]
pub async fn run_tests(
  flags: Flags,
  include: Option<Vec<String>>,
  ignore: Vec<PathBuf>,
  doc: bool,
  no_run: bool,
  fail_fast: Option<NonZeroUsize>,
  allow_none: bool,
  filter: Option<String>,
  shuffle: Option<u64>,
  concurrent_jobs: NonZeroUsize,
) -> Result<(), AnyError> {
  let program_state = ProgramState::build(flags.clone()).await?;
  let permissions = Permissions::from_options(&flags.clone().into());
  let specifiers_with_mode = fetch_specifiers_with_test_mode(
    program_state.clone(),
    include.unwrap_or_else(|| vec![".".to_string()]),
    ignore.clone(),
    doc,
  )
  .await?;

  if !allow_none && specifiers_with_mode.is_empty() {
    return Err(generic_error("No test modules found"));
  }

  let lib = if flags.unstable {
    TypeLib::UnstableDenoWindow
  } else {
    TypeLib::DenoWindow
  };

  check_specifiers(
    program_state.clone(),
    permissions.clone(),
    specifiers_with_mode.clone(),
    lib,
  )
  .await?;

  if no_run {
    return Ok(());
  }

  test_specifiers(
    program_state,
    permissions,
    specifiers_with_mode,
    fail_fast,
    filter,
    shuffle,
    concurrent_jobs,
  )
  .await?;

  Ok(())
}

#[allow(clippy::too_many_arguments)]
pub async fn run_tests_with_watch(
  flags: Flags,
  include: Option<Vec<String>>,
  ignore: Vec<PathBuf>,
  doc: bool,
  no_run: bool,
  fail_fast: Option<NonZeroUsize>,
  filter: Option<String>,
  shuffle: Option<u64>,
  concurrent_jobs: NonZeroUsize,
) -> Result<(), AnyError> {
  let program_state = ProgramState::build(flags.clone()).await?;
  let permissions = Permissions::from_options(&flags.clone().into());

  let lib = if flags.unstable {
    TypeLib::UnstableDenoWindow
  } else {
    TypeLib::DenoWindow
  };

  let handler = Arc::new(Mutex::new(FetchHandler::new(
    &program_state,
    Permissions::allow_all(),
    Permissions::allow_all(),
  )?));

  let include = include.unwrap_or_else(|| vec![".".to_string()]);
  let paths_to_watch: Vec<_> = include.iter().map(PathBuf::from).collect();

  let resolver = |changed: Option<Vec<PathBuf>>| {
    let paths_to_watch = paths_to_watch.clone();
    let paths_to_watch_clone = paths_to_watch.clone();

    let handler = handler.clone();
    let program_state = program_state.clone();
    let files_changed = changed.is_some();
    let include = include.clone();
    let ignore = ignore.clone();

    async move {
      let test_modules = if doc {
        collect_specifiers(include.clone(), &ignore, is_supported_test_ext)
      } else {
        collect_specifiers(include.clone(), &ignore, is_supported_test_path)
      }?;

      let mut paths_to_watch = paths_to_watch_clone;
      let mut modules_to_reload = if files_changed {
        Vec::new()
      } else {
        test_modules
          .iter()
          .filter_map(|url| deno_core::resolve_url(url.as_str()).ok())
          .collect()
      };

      let mut builder = GraphBuilder::new(
        handler,
        program_state.maybe_import_map.clone(),
        program_state.lockfile.clone(),
      );
      for specifier in test_modules.iter() {
        builder.add(specifier, false).await?;
      }
      builder
        .analyze_config_file(&program_state.maybe_config_file)
        .await?;
      let graph = builder.get_graph();

      for specifier in test_modules {
        fn get_dependencies<'a>(
          graph: &'a module_graph::Graph,
          module: &'a Module,
          // This needs to be accessible to skip getting dependencies if they're already there,
          // otherwise this will cause a stack overflow with circular dependencies
          output: &mut HashSet<&'a ModuleSpecifier>,
        ) -> Result<(), AnyError> {
          for dep in module.dependencies.values() {
            if let Some(specifier) = &dep.maybe_code {
              if !output.contains(specifier) {
                output.insert(specifier);

                get_dependencies(
                  graph,
                  graph.get_specifier(specifier)?,
                  output,
                )?;
              }
            }
            if let Some(specifier) = &dep.maybe_type {
              if !output.contains(specifier) {
                output.insert(specifier);

                get_dependencies(
                  graph,
                  graph.get_specifier(specifier)?,
                  output,
                )?;
              }
            }
          }

          Ok(())
        }

        // This test module and all it's dependencies
        let mut modules = HashSet::new();
        modules.insert(&specifier);
        get_dependencies(
          &graph,
          graph.get_specifier(&specifier)?,
          &mut modules,
        )?;

        paths_to_watch.extend(
          modules
            .iter()
            .filter_map(|specifier| specifier.to_file_path().ok()),
        );

        if let Some(changed) = &changed {
          for path in changed.iter().filter_map(|path| {
            deno_core::resolve_url_or_path(&path.to_string_lossy()).ok()
          }) {
            if modules.contains(&&path) {
              modules_to_reload.push(specifier);
              break;
            }
          }
        }
      }

      Ok((paths_to_watch, modules_to_reload))
    }
    .map(move |result| {
      if files_changed
        && matches!(result, Ok((_, ref modules)) if modules.is_empty())
      {
        ResolutionResult::Ignore
      } else {
        match result {
          Ok((paths_to_watch, modules_to_reload)) => {
            ResolutionResult::Restart {
              paths_to_watch,
              result: Ok(modules_to_reload),
            }
          }
          Err(e) => ResolutionResult::Restart {
            paths_to_watch,
            result: Err(e),
          },
        }
      }
    })
  };

  let operation = |modules_to_reload: Vec<ModuleSpecifier>| {
    let filter = filter.clone();
    let include = include.clone();
    let ignore = ignore.clone();
    let lib = lib.clone();
    let permissions = permissions.clone();
    let program_state = program_state.clone();

    async move {
      let specifiers_with_mode = fetch_specifiers_with_test_mode(
        program_state.clone(),
        include.clone(),
        ignore.clone(),
        doc,
      )
      .await?
      .iter()
      .filter(|(specifier, _)| modules_to_reload.contains(specifier))
      .cloned()
      .collect::<Vec<(ModuleSpecifier, TestMode)>>();

      check_specifiers(
        program_state.clone(),
        permissions.clone(),
        specifiers_with_mode.clone(),
        lib,
      )
      .await?;

      if no_run {
        return Ok(());
      }

      test_specifiers(
        program_state.clone(),
        permissions.clone(),
        specifiers_with_mode,
        fail_fast,
        filter.clone(),
        shuffle,
        concurrent_jobs,
      )
      .await?;

      Ok(())
    }
  };

  file_watcher::watch_func(resolver, operation, "Test").await?;

  Ok(())
}