Modify S1440: Migrate To LayC (#3231)

## Review

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- [ ] logical errors and incorrect information
- [ ] information gaps and missing content
- [ ] text style and tone
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rules/S1440/javascript/rule.adoc

@@ -1,20 +1,60 @@
 == Why is this an issue?
 
-include::../description.adoc[]
+In JavaScript, there are two types of comparison operators: strict and non-strict.
 
-include::../noncompliant.adoc[]
+* Strict operators: These operators compare both value and type. They are represented as `===` (strict equality) and `!==` (strict inequality). For example, `5 === "5"` would return `false` because, although the values are the same, the types are different (one is a number, the other is a string).
 
-include::../compliant.adoc[]
+* Non-Strict operators: These operators compare only value, not type. They are represented as `==` (equality) and `!=` (inequality). For example, `5 == "5"` would return `true` because the values are the same, even though the types are different.
 
-=== Exceptions
+It's generally recommended to use strict operators in JavaScript to avoid unexpected results due to JavaScript's type coercion. This is because non-strict operators can lead to some counter-intuitive results. For example, `0 == false` would return `true`, which might not be the expected outcome.
+
+[source,javascript,diff-id=1,diff-type=noncompliant]
+----
+function checkEqual(a, b) {
+  if (a == b) { // Noncompliant: using non-strict equality '=='
+    return "Equal";
+  } else {
+    return "Not equal";
+  }
+}
 
-Even if testing the equality of a variable against null doesn't do exactly what most JavaScript developers believe, usage of ``++==++`` or ``++!=++`` is tolerated in such context. In the following case, if ``++foo++`` hasn't been initialized, its default value is not ``++null++`` but ``++undefined++``. Nevertheless ``++undefined == null++``, so JavaScript developers get the expected behavior.
+console.log(checkEqual(0, false)); // Output: "Equal"
+----
+
+You should use the strict equality and inequality operators to prevent type coercion, avoid unexpected outcomes when comparing values of different types, and provide more predictable results.
 
-[source,javascript]
+[source,javascript,diff-id=1,diff-type=compliant]
 ----
-if(foo == null) {...}
+function checkEqual(a, b) {
+  if (a === b) {
+    return "Equal";
+  } else {
+    return "Not equal";
+  }
+}
+
+console.log(checkEqual(0, false)); // Output: "Not equal
 ----
 
+=== Exceptions
+
+The rule does not report on these cases:
+
+* Comparing two literal values
+* Evaluating the value of `typeof`
+* Comparing against `null`
+
+== Resources
+=== Documentation
+
+* https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Strict_equality[MDN - Strict equality]
+* https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Strict_inequality[MDN - Strict inequality]
+* https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Equality[MDN - Equality]
+* https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Inequality[MDN - Inequality]
+* https://developer.mozilla.org/en-US/docs/Glossary/Type_coercion[MDN - Type coercion]
+* https://developer.mozilla.org/en-US/docs/Glossary/Truthy[MDN - Truthy]
+* https://developer.mozilla.org/en-US/docs/Glossary/Falsy[MDN - Falsy]
+
 ifdef::env-github,rspecator-view[]
 
 '''