Fix < 5.1 and add tests

src/std/text.ab

@@ -22,7 +22,10 @@ pub fun replace(source, search, replace) {
 /// Replaces the first occurrence of a pattern in the content with the provided replace text.
 pub fun replace_once(source, search, replace) {
     search = replace(search, "\\", "\\\\")
-    replace = replace(replace, "\\", "\\\\")
+    if bash_version() >= 502 {
+        replace = replace(replace, "\\", "\\\\")
+    }
+
     return trust $ echo \$\{{nameof source}/{search}/{replace}} $
 }
 

src/tests/stdlib/replace.ab

@@ -3,10 +3,14 @@ import * from "std/text"
 // Output
 // apple apple
 // apple
-// banana\\
+// Succeeded
+// one\\two\\\\three\\\\\\
+// one\two\three\\
 
 main {
     echo replace("banana banana", "banana", "apple")
     echo replace("\\", "\\", "apple")
-    echo replace("banana\\", "\\", "\\\\")
+    echo replace("Succinctly\\", "inctly\\", "eeded")
+    echo replace("one\\two\\\\three\\\\\\", "\\", "\\\\")
+    echo replace("one\\two\\\\three\\\\\\", "\\\\", "\\")
 }

src/tests/stdlib/replace_once.ab

@@ -1,4 +1,12 @@
 import * from "std/text"
+
+// Output
+// Succeeded
+// one\\two\\three\\\.
+// one\two\three\\\.
+
 main {
     echo replace_once("Succinctly\\", "inctly\\", "eeded")
+    echo replace_once("one\\two\\\\three\\\\\\.", "\\", "\\\\")
+    echo replace_once("one\\two\\\\three\\\\\\.", "\\\\", "\\")
 }