fix: some tasks fail on Windows due to missing shell commands (#781)

This PR tries to address #452 by wrapping the commands 'rm', 'mkdir' and 'mv' with `shx`.
A whitelist of commands is maintained in the task runtime.

@eladb Is this what you had in mind when commenting on #540?

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

.projen/deps.json

@@ -137,6 +137,10 @@
       "name": "semver",
       "type": "bundled"
     },
+    {
+      "name": "shx",
+      "type": "bundled"
+    },
     {
       "name": "xmlbuilder2",
       "type": "bundled"

.projenrc.js

@@ -31,6 +31,7 @@ const project = new JsiiProject({
     '@iarna/toml',
     'xmlbuilder2',
     'ini',
+    'shx',
   ],
 
   devDeps: [

src/tasks/runtime.ts

@@ -1,5 +1,6 @@
 import { SpawnOptions, spawnSync } from 'child_process';
 import { existsSync, readFileSync, statSync } from 'fs';
+import { platform } from 'os';
 import { join, resolve } from 'path';
 import { format } from 'util';
 import * as chalk from 'chalk';
@@ -87,10 +88,29 @@ class RunTask {
       }
 
       if (step.exec) {
-        const command = step.exec;
+        let command = '';
+        let hasError = false;
+        const cmd = step.exec.split(' ')[0];
+        if (platform() == 'win32' && ['mkdir', 'mv', 'rm'].includes(cmd)) {
+          command = `shx ${step.exec}`;
+        } else {
+          command = step.exec;
+        }
         const cwd = step.cwd;
-        const result = this.shell({ command, cwd });
-        if (result.status !== 0) {
+        try {
+          const result = this.shell({
+            command,
+            cwd,
+          });
+          hasError = result.status !== 0;
+        } catch (e) {
+          // This is the error 'shx' will throw
+          if (e?.message?.startsWith('non-zero exit code:')) {
+            hasError = true;
+          }
+          throw e;
+        }
+        if (hasError) {
           throw new Error(`Task "${this.fullname}" failed when executing "${command}" (cwd: ${resolve(cwd ?? this.workdir)})`);
         }
       }
@@ -229,4 +249,4 @@ interface ShellOptions {
   readonly spawnOptions?: SpawnOptions;
   /** @default false */
   readonly quiet?: boolean;
-}
+}