Precompute _shouldAwait to avoid repeating costly computation

aweebit · Jul 26, 2023 · e66eda5 · e66eda5
1 parent 254865c
commit e66eda5
Showing 1 changed file with 12 additions and 10 deletions.
diff --git a/lib/command.js b/lib/command.js
@@ -63,6 +63,8 @@ class Command extends EventEmitter {
     this._asyncParsing = undefined;
     /** @type {boolean | undefined} */
     this._await = undefined;
+    /** @type {boolean | undefined} */
+    this._shouldAwait = undefined;
 
     // see .configureOutput() for docs
     this._outputConfiguration = {
@@ -304,7 +306,7 @@ class Command extends EventEmitter {
    */
 
   _parseArg(target, value, previous, handleError) {
-    const handleThenableError = this._shouldAwait() ? handleError : undefined;
+    const handleThenableError = this._shouldAwait ? handleError : undefined;
 
     try {
       if (this._shouldChainArgParserCalls(target)) {
@@ -959,6 +961,7 @@ Expecting one of '${allowedValues.join("', '")}'`);
 
   parse(argv, parseOptions) {
     this._asyncParsing = false;
+    this._setShouldAwait();
 
     try {
       const userArgs = this._prepareUserArgs(argv, parseOptions);
@@ -967,6 +970,7 @@ Expecting one of '${allowedValues.join("', '")}'`);
       return this;
     } finally {
       this._asyncParsing = undefined;
+      this._shouldAwait = undefined;
     }
   }
 
@@ -991,6 +995,7 @@ Expecting one of '${allowedValues.join("', '")}'`);
 
   async parseAsync(argv, parseOptions) {
     this._asyncParsing = true;
+    this._setShouldAwait();
 
     try {
       const userArgs = this._prepareUserArgs(argv, parseOptions);
@@ -999,6 +1004,7 @@ Expecting one of '${allowedValues.join("', '")}'`);
       return this;
     } finally {
       this._asyncParsing = undefined;
+      this._shouldAwait = undefined;
     }
   }
 
@@ -1021,14 +1027,10 @@ Expecting one of '${allowedValues.join("', '")}'`);
    * @api private
    */
 
-  _shouldAwait() {
-    let shouldAwait;
-    let cmd = this;
-    do {
-      shouldAwait = cmd._await ?? cmd._asyncParsing;
-      cmd = cmd.parent;
-    } while (shouldAwait === undefined);
-    return shouldAwait;
+  _setShouldAwait() {
+    for (let cmd = this; this._shouldAwait === undefined; cmd = cmd.parent) {
+      this._shouldAwait = cmd._await ?? cmd._asyncParsing;
+    }
   }
 
   /**
@@ -1078,7 +1080,7 @@ Expecting one of '${allowedValues.join("', '")}'`);
    */
 
   _optionalAwait(getPromises) {
-    if (this._shouldAwait()) {
+    if (this._shouldAwait) {
       const toAwait = getPromises();
       if (toAwait.length) return Promise.all(toAwait);
     }