From dc3dacdea7ca99ecbe5112ed8a3b1bd587b981a0 Mon Sep 17 00:00:00 2001
From: James Fredley <jamesfredley@users.noreply.github.com>
Date: Fri, 28 Feb 2025 16:21:27 -0500
Subject: [PATCH] Add tests for trimToNull() method

---
 .../grails/util/GrailsStringUtilsSpec.groovy  | 46 +++++++++++++++++++
 1 file changed, 46 insertions(+)

diff --git a/grails-core/src/test/groovy/grails/util/GrailsStringUtilsSpec.groovy b/grails-core/src/test/groovy/grails/util/GrailsStringUtilsSpec.groovy
index 09073e32167..2f9e71c7d6a 100644
--- a/grails-core/src/test/groovy/grails/util/GrailsStringUtilsSpec.groovy
+++ b/grails-core/src/test/groovy/grails/util/GrailsStringUtilsSpec.groovy
@@ -23,6 +23,39 @@ import spock.lang.Specification
  */
 class GrailsStringUtilsSpec extends Specification{
 
+    private static final String FOO = "foo";
+    static final String WHITESPACE;
+    static final String NON_WHITESPACE;
+    static final String HARD_SPACE;
+    static final String TRIMMABLE;
+    static final String NON_TRIMMABLE;
+
+    static {
+        final StringBuilder ws = new StringBuilder();
+        final StringBuilder nws = new StringBuilder();
+        final String hs = String.valueOf((char) 160);
+        final StringBuilder tr = new StringBuilder();
+        final StringBuilder ntr = new StringBuilder();
+        for (int i = 0; i < Character.MAX_VALUE; i++) {
+            if (Character.isWhitespace((char) i)) {
+                ws.append((char) i);
+                if (i > 32) {
+                    ntr.append((char) i);
+                }
+            } else if (i < 40) {
+                nws.append((char) i);
+            }
+        }
+        for (int i = 0; i <= 32; i++) {
+            tr.append((char) i);
+        }
+        WHITESPACE = ws.toString();
+        NON_WHITESPACE = nws.toString();
+        HARD_SPACE = hs;
+        TRIMMABLE = tr.toString();
+        NON_TRIMMABLE = ntr.toString();
+    }
+
     void "Test toBoolean"() {
         expect:
             GrailsStringUtils.toBoolean("on") == true
@@ -63,4 +96,17 @@ class GrailsStringUtilsSpec extends Specification{
             GrailsStringUtils.trimStart("abc", "ab") == 'c'
             GrailsStringUtils.trimStart("abc", "c") == 'abc'
     }
+
+    void "Test trimToNull method"() {
+        expect:
+            GrailsStringUtils.trimToNull(FOO + "  ") == FOO
+            GrailsStringUtils.trimToNull(" " + FOO + "  ") == FOO
+            GrailsStringUtils.trimToNull(" " + FOO) == FOO
+            GrailsStringUtils.trimToNull(FOO + "") == FOO
+            GrailsStringUtils.trimToNull(" \t\r\n\b ") == null
+            GrailsStringUtils.trimToNull(TRIMMABLE) == null
+            GrailsStringUtils.trimToNull(NON_TRIMMABLE) == NON_TRIMMABLE
+            GrailsStringUtils.trimToNull("") == null
+            GrailsStringUtils.trimToNull(null) == null
+    }
 }