feat: perform sanity check in watch mode

lib/core/generate.ts

@@ -1,6 +1,5 @@
-import glob from "glob";
-
 import { alerts } from "./alerts";
+import { listFilesAndPerformSanityChecks } from "./list-files-and-perform-sanity-checks";
 import { ConfigOptions } from "./types";
 import { writeFile } from "./write-file";
 
@@ -14,22 +13,12 @@ export const generate = async (
   pattern: string,
   options: ConfigOptions
 ): Promise<void> => {
-  // Find all the files that match the provided pattern.
-  const files = glob.sync(pattern, { ignore: options.ignore });
+  const files = listFilesAndPerformSanityChecks(pattern, options);
 
-  if (!files || !files.length) {
-    alerts.error("No files found.");
+  if (files.length === 0) {
     return;
   }
 
-  // This case still works as expected but it's easy to do on accident so
-  // provide a (hopefully) helpful warning.
-  if (files.length === 1) {
-    alerts.warn(
-      `Only 1 file found for ${pattern}. If using a glob pattern (eg: dir/**/*.scss) make sure to wrap in quotes (eg: "dir/**/*.scss").`
-    );
-  }
-
   alerts.success(
     `Found ${files.length} file${
       files.length === 1 ? `` : `s`

lib/core/list-files-and-perform-sanity-checks.ts

@@ -0,0 +1,33 @@
+import glob from "glob";
+
+import { alerts } from "./alerts";
+import { ConfigOptions } from "./types";
+
+/**
+ * Return the files matching the given pattern and alert the user if only 0 or 1
+ * files matched.
+ *
+ * @param pattern the file pattern to generate type definitions for
+ * @param options the CLI options
+ */
+export function listFilesAndPerformSanityChecks(
+  pattern: string,
+  options: ConfigOptions
+): string[] {
+  // Find all the files that match the provided pattern.
+  const files = glob.sync(pattern, { ignore: options.ignore });
+
+  if (!files || !files.length) {
+    alerts.error("No files found.");
+  }
+
+  // This case still works as expected but it's easy to do on accident so
+  // provide a (hopefully) helpful warning.
+  if (files.length === 1) {
+    alerts.warn(
+      `Only 1 file found for ${pattern}. If using a glob pattern (eg: dir/**/*.scss) make sure to wrap in quotes (eg: "dir/**/*.scss").`
+    );
+  }
+
+  return files;
+}

lib/core/watch.ts

@@ -4,6 +4,7 @@ import { alerts } from "./alerts";
 import { removeSCSSTypeDefinitionFile } from "./remove-file";
 import { writeFile } from "./write-file";
 import { ConfigOptions } from "./types";
+import { listFilesAndPerformSanityChecks } from "./list-files-and-perform-sanity-checks";
 
 /**
  * Watch a file glob and generate the corresponding types.
@@ -12,6 +13,10 @@ import { ConfigOptions } from "./types";
  * @param options the CLI options
  */
 export const watch = (pattern: string, options: ConfigOptions): void => {
+  // This is called so that we print a warning instead if no files matched the
+  // pattern
+  listFilesAndPerformSanityChecks(pattern, options);
+
   alerts.success("Watching files...");
 
   chokidar