1 files changed, 79 insertions, 0 deletions
diff --git a/cli/lint.rs b/cli/lint.rs
new file mode 100644
index 000000000..5dfbcaf40
--- /dev/null
+++ b/cli/lint.rs
@@ -0,0 +1,79 @@
+// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
+
+//! This module provides file formating utilities using
+//! [`deno_lint`](https://github.com/denoland/deno_lint).
+//!
+//! At the moment it is only consumed using CLI but in
+//! the future it can be easily extended to provide
+//! the same functions as ops available in JS runtime.
+
+use crate::colors;
+use crate::file_fetcher::map_file_extension;
+use crate::fmt::collect_files;
+use crate::fmt_errors;
+use crate::swc_util;
+use deno_core::ErrBox;
+use deno_lint::diagnostic::LintDiagnostic;
+use deno_lint::linter::Linter;
+use deno_lint::rules;
+use std::fs;
+use std::path::PathBuf;
+
+pub fn lint_files(args: Vec<String>) -> Result<(), ErrBox> {
+  let target_files = collect_files(args)?;
+
+  let mut error_counts = 0;
+
+  for file_path in target_files {
+    let file_diagnostics = lint_file(file_path)?;
+    error_counts += file_diagnostics.len();
+    for d in file_diagnostics.iter() {
+      let fmt_diagnostic = format_diagnostic(d);
+      eprintln!("{}\n", fmt_diagnostic);
+    }
+  }
+
+  if error_counts > 0 {
+    eprintln!("Found {} problems", error_counts);
+    std::process::exit(1);
+  }
+
+  Ok(())
+}
+
+fn lint_file(file_path: PathBuf) -> Result<Vec<LintDiagnostic>, ErrBox> {
+  let file_name = file_path.to_string_lossy().to_string();
+  let source_code = fs::read_to_string(&file_path)?;
+  let media_type = map_file_extension(&file_path);
+  let syntax = swc_util::get_syntax_for_media_type(media_type);
+
+  let mut linter = Linter::default();
+  let lint_rules = rules::get_recommended_rules();
+
+  let file_diagnostics =
+    linter.lint(file_name, source_code, syntax, lint_rules)?;
+
+  Ok(file_diagnostics)
+}
+
+fn format_diagnostic(d: &LintDiagnostic) -> String {
+  let pretty_message = format!(
+    "({}) {}",
+    colors::gray(d.code.to_string()),
+    d.message.clone()
+  );
+
+  fmt_errors::format_stack(
+    true,
+    pretty_message,
+    Some(d.line_src.clone()),
+    Some(d.location.col as i64),
+    Some((d.location.col + d.snippet_length) as i64),
+    &[fmt_errors::format_location(
+      d.location.filename.clone(),
+      d.location.line as i64,
+      d.location.col as i64,
+    )],
+    0,
+  )
+}