2 files changed, 89 insertions, 1 deletions

diff --git a/cli/tools/registry/diagnostics.rs b/cli/tools/registry/diagnostics.rs
index 34f08b666..54b281194 100644
--- a/cli/tools/registry/diagnostics.rs
+++ b/cli/tools/registry/diagnostics.rs
@@ -119,6 +119,10 @@ pub enum PublishDiagnostic {
     range: SourceRange,
   },
   SyntaxError(ParseDiagnostic),
+  MissingLicense {
+    /// This only exists because diagnostics require a location.
+    expected_path: PathBuf,
+  },
 }
 
 impl PublishDiagnostic {
@@ -168,6 +172,8 @@ impl Diagnostic for PublishDiagnostic {
       MissingConstraint { .. } => DiagnosticLevel::Error,
       BannedTripleSlashDirectives { .. } => DiagnosticLevel::Error,
       SyntaxError { .. } => DiagnosticLevel::Error,
+      // todo(#24676): make this an error in Deno 1.46
+      MissingLicense { .. } => DiagnosticLevel::Warning,
     }
   }
 
@@ -187,6 +193,7 @@ impl Diagnostic for PublishDiagnostic {
         Cow::Borrowed("banned-triple-slash-directives")
       }
       SyntaxError { .. } => Cow::Borrowed("syntax-error"),
+      MissingLicense { .. } => Cow::Borrowed("missing-license"),
     }
   }
 
@@ -208,6 +215,7 @@ impl Diagnostic for PublishDiagnostic {
       MissingConstraint { specifier, .. } => Cow::Owned(format!("specifier '{}' is missing a version constraint", specifier)),
       BannedTripleSlashDirectives { .. } => Cow::Borrowed("triple slash directives that modify globals are not allowed"),
       SyntaxError(diagnostic) => diagnostic.message(),
+      MissingLicense { .. } => Cow::Borrowed("missing license file"),
     }
   }
 
@@ -275,6 +283,9 @@ impl Diagnostic for PublishDiagnostic {
         text_info: Cow::Borrowed(text_info),
       },
       SyntaxError(diagnostic) => diagnostic.location(),
+      MissingLicense { expected_path } => DiagnosticLocation::Path {
+        path: expected_path.clone(),
+      },
     }
   }
 
@@ -355,6 +366,7 @@ impl Diagnostic for PublishDiagnostic {
         }],
       }),
       SyntaxError(diagnostic) => diagnostic.snippet(),
+      MissingLicense { .. } => None,
     }
   }
 
@@ -388,6 +400,9 @@ impl Diagnostic for PublishDiagnostic {
         Cow::Borrowed("remove the triple slash directive"),
       ),
       SyntaxError(diagnostic) => diagnostic.hint(),
+      MissingLicense { .. } => Some(
+        Cow::Borrowed("add a LICENSE file to the package and ensure it is not ignored from being published"),
+      ),
     }
   }
 
@@ -424,7 +439,8 @@ impl Diagnostic for PublishDiagnostic {
       | UnsupportedJsxTsx { .. }
       | ExcludedModule { .. }
       | MissingConstraint { .. }
-      | BannedTripleSlashDirectives { .. } => None,
+      | BannedTripleSlashDirectives { .. }
+      | MissingLicense { .. } => None,
     }
   }
 
@@ -474,6 +490,7 @@ impl Diagnostic for PublishDiagnostic {
         Cow::Borrowed("or set their 'lib' compiler option appropriately"),
       ]),
       SyntaxError(diagnostic) => diagnostic.info(),
+      MissingLicense { .. } => Cow::Borrowed(&[]),
     }
   }
 
@@ -507,6 +524,9 @@ impl Diagnostic for PublishDiagnostic {
         "https://jsr.io/go/banned-triple-slash-directives",
       )),
       SyntaxError(diagnostic) => diagnostic.docs_url(),
+      MissingLicense { .. } => {
+        Some(Cow::Borrowed("https://jsr.io/go/missing-license"))
+      }
     }
   }
 }
diff --git a/cli/tools/registry/mod.rs b/cli/tools/registry/mod.rs
index 2e781ccee..1c4e1bea7 100644
--- a/cli/tools/registry/mod.rs
+++ b/cli/tools/registry/mod.rs
@@ -462,6 +462,13 @@ impl PublishPreparer {
           &publish_paths,
           &diagnostics_collector,
         );
+
+        if !has_license_file(publish_paths.iter().map(|p| &p.specifier)) {
+          diagnostics_collector.push(PublishDiagnostic::MissingLicense {
+            expected_path: root_dir.join("LICENSE"),
+          });
+        }
+
         tar::create_gzipped_tarball(
           &publish_paths,
           LazyGraphSourceParser::new(&source_cache, &graph),
@@ -1187,6 +1194,36 @@ async fn check_if_git_repo_dirty(cwd: &Path) -> Option<String> {
   }
 }
 
+fn has_license_file<'a>(
+  mut specifiers: impl Iterator<Item = &'a ModuleSpecifier>,
+) -> bool {
+  let allowed_license_files = {
+    let files = HashSet::from([
+      "license",
+      "license.md",
+      "license.txt",
+      "licence",
+      "licence.md",
+      "licence.txt",
+    ]);
+    if cfg!(debug_assertions) {
+      for file in &files {
+        assert_eq!(*file, file.to_lowercase());
+      }
+    }
+    files
+  };
+  specifiers.any(|specifier| {
+    specifier
+      .path()
+      .rsplit_once('/')
+      .map(|(_, file)| {
+        allowed_license_files.contains(file.to_lowercase().as_str())
+      })
+      .unwrap_or(false)
+  })
+}
+
 #[allow(clippy::print_stderr)]
 fn ring_bell() {
   // ASCII code for the bell character.
@@ -1195,6 +1232,10 @@ fn ring_bell() {
 
 #[cfg(test)]
 mod tests {
+  use deno_ast::ModuleSpecifier;
+
+  use crate::tools::registry::has_license_file;
+
   use super::tar::PublishableTarball;
   use super::tar::PublishableTarballFile;
   use super::verify_version_manifest;
@@ -1296,4 +1337,31 @@ mod tests {
 
     assert!(verify_version_manifest(meta_bytes, &package).is_err());
   }
+
+  #[test]
+  fn test_has_license_files() {
+    fn has_license_file_str(expected: &[&str]) -> bool {
+      let specifiers = expected
+        .iter()
+        .map(|s| ModuleSpecifier::parse(s).unwrap())
+        .collect::<Vec<_>>();
+      has_license_file(specifiers.iter())
+    }
+
+    assert!(has_license_file_str(&["file:///LICENSE"]));
+    assert!(has_license_file_str(&["file:///license"]));
+    assert!(has_license_file_str(&["file:///LICENSE.txt"]));
+    assert!(has_license_file_str(&["file:///LICENSE.md"]));
+    assert!(has_license_file_str(&["file:///LICENCE"]));
+    assert!(has_license_file_str(&["file:///LICENCE.txt"]));
+    assert!(has_license_file_str(&["file:///LICENCE.md"]));
+    assert!(has_license_file_str(&[
+      "file:///other",
+      "file:///test/LICENCE.md"
+    ]),);
+    assert!(!has_license_file_str(&[
+      "file:///other",
+      "file:///test/tLICENSE"
+    ]),);
+  }
 }