From 820259feef1fa5bf0fbf5d8186904bc61f3bd4a6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Leosvel=20P=C3=A9rez=20Espinosa?=
 <leosvel.perez.espinosa@gmail.com>
Date: Fri, 5 May 2023 09:47:24 +0100
Subject: [PATCH] fix(core): handle schema property with const value

---
 packages/nx/src/utils/params.spec.ts | 21 +++++++++++++++++++++
 packages/nx/src/utils/params.ts      |  7 +++++++
 2 files changed, 28 insertions(+)

diff --git a/packages/nx/src/utils/params.spec.ts b/packages/nx/src/utils/params.spec.ts
index bd3abfbfcd7f3..13420d56b269d 100644
--- a/packages/nx/src/utils/params.spec.ts
+++ b/packages/nx/src/utils/params.spec.ts
@@ -982,6 +982,27 @@ describe('params', () => {
         ).not.toThrow();
       });
 
+      it('should handle const value', () => {
+        const schema = {
+          properties: {
+            a: {
+              const: 3,
+            },
+          },
+        };
+        expect(() => validateOptsAgainstSchema({ a: 3 }, schema)).not.toThrow();
+        expect(() =>
+          validateOptsAgainstSchema({ a: true }, schema)
+        ).toThrowErrorMatchingInlineSnapshot(
+          `"Property 'a' does not match the schema. 'true' should be '3'."`
+        );
+        expect(() =>
+          validateOptsAgainstSchema({ a: 123 }, schema)
+        ).toThrowErrorMatchingInlineSnapshot(
+          `"Property 'a' does not match the schema. '123' should be '3'."`
+        );
+      });
+
       describe('array', () => {
         it('should handle validating patterns', () => {
           const schema = {
diff --git a/packages/nx/src/utils/params.ts b/packages/nx/src/utils/params.ts
index c9ab3b783a88e..5b6ff5717a4c2 100644
--- a/packages/nx/src/utils/params.ts
+++ b/packages/nx/src/utils/params.ts
@@ -33,6 +33,7 @@ type PropertyDescription = {
     | { $source: 'projectName' }
     | { $source: 'unparsed' };
   additionalProperties?: boolean;
+  const?: any;
   'x-prompt'?:
     | string
     | { message: string; type: string; items?: any[]; multiselect?: boolean };
@@ -359,6 +360,12 @@ function validateProperty(
 
   const isPrimitive = typeof value !== 'object';
   if (isPrimitive) {
+    if (schema.const !== undefined && value !== schema.const) {
+      throw new SchemaError(
+        `Property '${propName}' does not match the schema. '${value}' should be '${schema.const}'.`
+      );
+    }
+
     if (Array.isArray(schema.type)) {
       const passes = schema.type.some((t) => {
         try {