From c2c90ba6c4b3ca45bb5085c2a2046b0b57f9823c Mon Sep 17 00:00:00 2001
From: Marcelo Shima <marceloshima@gmail.com>
Date: Thu, 1 Sep 2022 11:02:03 -0300
Subject: [PATCH] implement strict priorities.

---
 lib/command.js          | 28 +++++++++++++++++-----------
 typings/index.d.ts      |  4 ++--
 typings/index.test-d.ts |  2 +-
 3 files changed, 20 insertions(+), 14 deletions(-)

diff --git a/lib/command.js b/lib/command.js
index 7f125e5e8..4e97e80c1 100644
--- a/lib/command.js
+++ b/lib/command.js
@@ -57,13 +57,14 @@ class Command extends EventEmitter {
     this._showHelpAfterError = false;
     this._showSuggestionAfterError = true;
 
-    // 'unknown' value is left out on purpose, should be treated as such
-    this._precedence = [
-      'default',
-      'implied', // implied by others configs
-      'config', // placeholder for configuration files
+    this._strictPriority = false;
+    this._priorities = [
+      'cli',
       'env',
-      'cli'
+      'config', // placeholder for configuration files
+      'implied', // implied by others configs
+      'default', // default option value
+      undefined // initial state, not touched yet
     ];
 
     // see .configureOutput() for docs
@@ -421,6 +422,13 @@ Expecting one of '${allowedValues.join("', '")}'`);
     return this;
   }
 
+  strictPriority(priorities) {
+    this._strictPriority = true;
+    if (priorities) {
+      this._priorities = priorities;
+    }
+  }
+
   /**
    * Register callback to use as replacement for calling process.exit.
    *
@@ -802,7 +810,8 @@ Expecting one of '${allowedValues.join("', '")}'`);
     * @return {Command} `this` command for chaining
     */
 
-  setOptionValueWithSource(key, value, source = 'unknown') {
+  setOptionValueWithSource(key, value, source = null) {
+    if (this._strictPriority && !this._isNewSourcePreferred(source, this.getOptionValueSource(key))) return;
     if (this._storeOptionsAsProperties) {
       this[key] = value;
     } else {
@@ -1612,10 +1621,7 @@ Expecting one of '${allowedValues.join("', '")}'`);
    * @api private
    */
   _isNewSourcePreferred(newSource, existingSource) {
-    // unknown source should always take precedence. undefined existingSource means option not set.
-    if (newSource == null || !this._precedence.includes(newSource) || existingSource === undefined) return true;
-    if (existingSource === null || !this._precedence.includes(existingSource)) return false;
-    return this._precedence.indexOf(newSource) >= this._precedence.indexOf(existingSource);
+    return this._priorities.indexOf(newSource) <= this._priorities.indexOf(existingSource);
   }
 
   /**
diff --git a/typings/index.d.ts b/typings/index.d.ts
index 93dbec84a..aa65b5f69 100644
--- a/typings/index.d.ts
+++ b/typings/index.d.ts
@@ -266,7 +266,7 @@ export interface OutputConfiguration {
 
 export type AddHelpTextPosition = 'beforeAll' | 'before' | 'after' | 'afterAll';
 export type HookEvent = 'preSubcommand' | 'preAction' | 'postAction';
-export type OptionValueSource = 'default' | 'implied' | 'config' | 'env' | 'cli' | 'unknown';
+export type OptionValueSource = 'default' | 'implied' | 'config' | 'env' | 'cli' | null;
 
 export interface OptionValues {
   [key: string]: any;
@@ -595,7 +595,7 @@ export class Command {
   /**
    * Retrieve option value source.
    */
-  getOptionValueSource(key: string): OptionValueSource;
+  getOptionValueSource(key: string): OptionValueSource | undefined;
 
   /**
    * Alter parsing of short flags with optional values.
diff --git a/typings/index.test-d.ts b/typings/index.test-d.ts
index 94c0b53d1..7b8af12ea 100644
--- a/typings/index.test-d.ts
+++ b/typings/index.test-d.ts
@@ -172,7 +172,7 @@ expectType<commander.Command>(program.setOptionValue('example', true));
 expectType<commander.Command>(program.setOptionValueWithSource('example', [], 'cli'));
 
 // getOptionValueSource
-expectType<commander.OptionValueSource>(program.getOptionValueSource('example'));
+expectType<commander.OptionValueSource | undefined>(program.getOptionValueSource('example'));
 
 // combineFlagAndOptionalValue
 expectType<commander.Command>(program.combineFlagAndOptionalValue());