From a41def836077f09b4ba0ccf953e600527ef4720f Mon Sep 17 00:00:00 2001
From: Jos de Jong <wjosdejong@gmail.com>
Date: Wed, 13 Mar 2024 14:25:56 +0100
Subject: [PATCH] fix: #3172 simplify `"true and true"`

---
 HISTORY.md                                            | 1 +
 src/function/algebra/simplifyCore.js                  | 3 +++
 test/unit-tests/function/algebra/simplifyCore.test.js | 9 +++++++++
 3 files changed, 13 insertions(+)

diff --git a/HISTORY.md b/HISTORY.md
index 8f391883e0..7dac6a8d2f 100644
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -5,6 +5,7 @@
 
 - Docs: implement an interactive version of the Lorenz example, and show the
   chart full screen (#3151). Thanks @dvd101x.
+- Fix #3172: simplify `"true and true"`.
 - Fix #3163: `toTex` wrongly returning `Infinity` for large BigNumbers.
 - Fix #3162: add license information about CSParse (#3164).
 - Fix: expose `math.Unit.ALIASES` (see #3175).
diff --git a/src/function/algebra/simplifyCore.js b/src/function/algebra/simplifyCore.js
index 86ebe850da..f8b09209f2 100644
--- a/src/function/algebra/simplifyCore.js
+++ b/src/function/algebra/simplifyCore.js
@@ -244,6 +244,9 @@ export const createSimplifyCore = /* #__PURE__ */ factory(name, dependencies, ({
         if (isConstantNode(a0)) {
           if (a0.value) {
             if (isAlwaysBoolean(a1)) return a1
+            if (isConstantNode(a1)) {
+              return a1.value ? nodeT : nodeF
+            }
           } else {
             return nodeF
           }
diff --git a/test/unit-tests/function/algebra/simplifyCore.test.js b/test/unit-tests/function/algebra/simplifyCore.test.js
index e4e5f4d371..18f04758cb 100644
--- a/test/unit-tests/function/algebra/simplifyCore.test.js
+++ b/test/unit-tests/function/algebra/simplifyCore.test.js
@@ -30,12 +30,21 @@ describe('simplifyCore', function () {
     testSimplifyCore('not (not (p and q))', 'p and q')
     testSimplifyCore('1 and not done', 'not done')
     testSimplifyCore('false and you(know, it)', 'false')
+    testSimplifyCore('you(know, it) and false', 'false')
     testSimplifyCore('(p or q) and "you"', 'p or q')
     testSimplifyCore('something and ""', 'false')
     testSimplifyCore('false or not(way)', 'not way')
     testSimplifyCore('6 or dozen/2', 'true')
     testSimplifyCore('(a and b) or 0', 'a and b')
     testSimplifyCore('consequences or true', 'true')
+    testSimplifyCore('true or true', 'true')
+    testSimplifyCore('1 or 2', 'true')
+    testSimplifyCore('0 or 2', 'true')
+    testSimplifyCore('2 or 0', 'true')
+    testSimplifyCore('true and true', 'true')
+    testSimplifyCore('2 and 2', 'true')
+    testSimplifyCore('0 and 2', 'false')
+    testSimplifyCore('2 and 0', 'false')
     testSimplifyCore('(1*x + y*0)*1+0', 'x')
     testSimplifyCore('sin(x+0)*1', 'sin(x)')
     testSimplifyCore('((x+0)*1)', 'x')