Add fs Promises API support

metarhia · Mar 21, 2019 · d701512 · d701512
1 parent 8f31db6
commit d701512
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Showing 2 changed files with 25 additions and 7 deletions.
diff --git a/.eslintrc.yml b/.eslintrc.yml
@@ -1,6 +1,8 @@
 env:
   es6: true
   node: true
+parserOptions:
+  ecmaVersion: 8
 extends:
   - eslint:recommended
   - plugin:prettier/recommended
@@ -104,7 +106,9 @@ rules:
     - always
   space-before-function-paren:
     - error
-    - never
+    - anonymous: never
+      named: never
+      asyncArrow: always
   space-in-parens:
     - error
     - never

diff --git a/sandboxed-fs.js b/sandboxed-fs.js
@@ -89,6 +89,9 @@ const twoPathFunctionsWrapper = (func, path, allowTmp) => (p1, p2, ...args) =>
     ...args
   );
 
+const asyncWrapper = wrapper => (...wrapperArgs) => async (...args) =>
+  wrapper(...wrapperArgs)(...args);
+
 const functionTypes = {
   pathFunctions: {
     names: [
@@ -110,16 +113,19 @@ const functionTypes = {
       'utimes',
     ],
     wrapper: pathFunctionsWrapper,
+    asyncWrapper: asyncWrapper(pathFunctionsWrapper),
     hasSyncCounterpart: true,
   },
   stringPathFunctions: {
     names: ['mkdtemp'],
     wrapper: stringPathFunctionsWrapper,
+    asyncWrapper: asyncWrapper(stringPathFunctionsWrapper),
     hasSyncCounterpart: true,
   },
   pathFunctionsWithNative: {
     names: ['realpath'],
     wrapper: pathFunctionsWithNativeWrapper,
+    asyncWrapper: asyncWrapper(pathFunctionsWithNativeWrapper),
     hasSyncCounterpart: true,
   },
   pathNonSyncFunctions: {
@@ -136,27 +142,35 @@ const functionTypes = {
   fileFunctions: {
     names: ['appendFile', 'readFile', 'writeFile'],
     wrapper: fileFunctionsWrapper,
+    asyncWrapper: asyncWrapper(fileFunctionsWrapper),
     hasSyncCounterpart: true,
   },
   twoPathFunctions: {
     names: ['copyFile', 'link', 'rename', 'symlink'],
     wrapper: twoPathFunctionsWrapper,
+    asyncWrapper: asyncWrapper(twoPathFunctionsWrapper),
     hasSyncCounterpart: true,
   },
 };
 
 sandboxedFs.bind = (path, allowTmp = true) => {
-  const wrapped = Object.assign({}, fs);
+  const promises = Object.assign({}, fs.promises);
+  const wrapped = Object.assign({}, fs, { promises });
 
   for (const typeName of Object.keys(functionTypes)) {
     const type = functionTypes[typeName];
     for (const name of type.names) {
       const fn = fs[name];
-      if (!fn) continue;
-      wrapped[name] = type.wrapper(fn, path, allowTmp);
-      if (type.hasSyncCounterpart) {
-        const syncName = name + 'Sync';
-        wrapped[syncName] = type.wrapper(fs[syncName], path, allowTmp);
+      const promiseFn = fs.promises[name];
+      if (fn) {
+        wrapped[name] = type.wrapper(fn, path, allowTmp);
+        if (type.hasSyncCounterpart) {
+          const syncName = name + 'Sync';
+          wrapped[syncName] = type.wrapper(fs[syncName], path, allowTmp);
+        }
+      }
+      if (promiseFn) {
+        wrapped.promises[name] = type.asyncWrapper(promiseFn, path, allowTmp);
       }
     }
   }