feat: add "deno coverage" subcommand (#8664)

This commit adds a new subcommand called "coverage" 
which can generate code coverage reports to stdout in 
multiple formats from code coverage profiles collected to disk.

Currently this supports outputting a pretty printed diff and 
the lcov format for interoperability with third-party services and tools.

Code coverage is still collected via other subcommands 
that run and collect code coverage such as 
"deno test --coverage=<directory>" but that command no 
longer prints a pretty printed report at the end of a test 
run with coverage collection enabled.

The restrictions on which files that can be reported on has 
also been relaxed and are fully controllable with the include 
and exclude regular expression flags on the coverage subcommand.

Co-authored-by: Luca Casonato <lucacasonato@yahoo.com>

1 files changed, 36 insertions, 15 deletions

diff --git a/cli/main.rs b/cli/main.rs
index b9516e704..e957b9342 100644
--- a/cli/main.rs
+++ b/cli/main.rs
@@ -978,6 +978,34 @@ async fn run_command(flags: Flags, script: String) -> Result<(), AnyError> {
   Ok(())
 }
 
+async fn coverage_command(
+  flags: Flags,
+  files: Vec<PathBuf>,
+  ignore: Vec<PathBuf>,
+  include: Vec<String>,
+  exclude: Vec<String>,
+  lcov: bool,
+) -> Result<(), AnyError> {
+  if !flags.unstable {
+    exit_unstable("compile");
+  }
+
+  if files.is_empty() {
+    println!("No matching coverage profiles found");
+    std::process::exit(1);
+  }
+
+  tools::coverage::cover_files(
+    flags.clone(),
+    files,
+    ignore,
+    include,
+    exclude,
+    lcov,
+  )
+  .await
+}
+
 async fn test_command(
   flags: Flags,
   include: Option<Vec<String>>,
@@ -1047,7 +1075,6 @@ async fn test_command(
   let mut maybe_coverage_collector =
     if let Some(ref coverage_dir) = program_state.coverage_dir {
       let session = worker.create_inspector_session();
-
       let coverage_dir = PathBuf::from(coverage_dir);
       let mut coverage_collector =
         tools::coverage::CoverageCollector::new(coverage_dir, session);
@@ -1067,20 +1094,6 @@ async fn test_command(
 
   if let Some(coverage_collector) = maybe_coverage_collector.as_mut() {
     coverage_collector.stop_collecting().await?;
-
-    // TODO(caspervonb) extract reporting into it's own subcommand.
-    // For now, we'll only report for the command that passed --coverage as a flag.
-    if flags.coverage_dir.is_some() {
-      let mut exclude = test_modules.clone();
-      exclude.push(main_module.clone());
-      tools::coverage::report_coverages(
-        program_state.clone(),
-        &coverage_collector.dir,
-        quiet,
-        exclude,
-      )
-      .await?;
-    }
   }
 
   Ok(())
@@ -1172,6 +1185,14 @@ fn get_subcommand(
       target,
     } => compile_command(flags, source_file, output, args, target, lite)
       .boxed_local(),
+    DenoSubcommand::Coverage {
+      files,
+      ignore,
+      include,
+      exclude,
+      lcov,
+    } => coverage_command(flags, files, ignore, include, exclude, lcov)
+      .boxed_local(),
     DenoSubcommand::Fmt {
       check,
       files,