fix 'toString' error and improve messages

Author: typicode

src/installer/checkGitVersion.ts

@@ -6,10 +6,10 @@ export function checkGitVersion(): void {
   const { status, stderr, stdout } = cp.spawnSync('git', ['--version'])
 
   if (status !== 0) {
-    throw new Error(stderr.toString())
+    throw new Error(`git --version command failed. Got ${String(stderr)}.`)
   }
 
-  const [version] = findVersions(stdout.toString())
+  const [version] = findVersions(String(stdout))
 
   if (compareVersions(version, '2.13.0') === -1) {
     throw new Error(`Husky requires Git >=2.13.0. Got v${version}.`)

src/installer/gitRevParse.ts

@@ -16,7 +16,7 @@ export function gitRevParse(cwd = process.cwd()): GitRevParseResult {
   )
 
   if (status !== 0) {
-    throw new Error(stderr.toString())
+    throw new Error(`git rev-parse command failed. Got ${String(stderr)}`)
   }
 
   const [prefix, gitCommonDir] = stdout