create getVersion fn

Signed-off-by: shmck <shawn.j.mckay@gmail.com>

Author: ShMcK

src/channel/index.ts

@@ -94,6 +94,8 @@ class Channel implements Channel {
         // setup tutorial config (save watcher, test runner, etc)
         await this.context.setTutorial(this.workspaceState, data)
 
+        // validate dependencies
+
         const error: E.ErrorMessage | void = await tutorialConfig({ config: data.config }).catch((error: Error) => ({
           type: 'UnknownError',
           message: `Location: tutorial config.\n\n${error.message}`,

src/services/dependencies/index.ts

@@ -0,0 +1,14 @@
+import node from '../node'
+
+const semverRegex = /(?<=^v?|\sv?)(?:0|[1-9]\d*)\.(?:0|[1-9]\d*)\.(?:0|[1-9]\d*)(?:-(?:0|[1-9]\d*|[\da-z-]*[a-z-][\da-z-]*)(?:\.(?:0|[1-9]\d*|[\da-z-]*[a-z-][\da-z-]*))*)?(?:\+[\da-z-]+(?:\.[\da-z-]+)*)?(?=$|\s)/gi
+
+export const getVersion = async (name: string): Promise<string | null> => {
+  const { stdout, stderr } = await node.exec(`${name} --version`)
+  if (!stderr) {
+    const match = stdout.match(semverRegex)
+    if (match) {
+      return match[0]
+    }
+  }
+  return null
+}