From cb9eec50c7e84e3c4bbeab6f419cd86d1d30be1d Mon Sep 17 00:00:00 2001
From: Matus Faro <matus@matus.io>
Date: Fri, 29 Nov 2024 20:24:29 -0500
Subject: [PATCH] Fix multiple field mappings conflict with each other,
 replacing own value

---
 .../io/dataspray/singletable/ExpressionBuilder.java    | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/single-table/src/main/java/io/dataspray/singletable/ExpressionBuilder.java b/single-table/src/main/java/io/dataspray/singletable/ExpressionBuilder.java
index 09c5023..2660eae 100644
--- a/single-table/src/main/java/io/dataspray/singletable/ExpressionBuilder.java
+++ b/single-table/src/main/java/io/dataspray/singletable/ExpressionBuilder.java
@@ -210,9 +210,7 @@ public P delete(String fieldName, Object object) {
 
     @Override
     public String fieldMapping(String fieldName) {
-        String mappedName = "#" + sanitizeFieldMapping(fieldName);
-        nameMap.put(mappedName, fieldName);
-        return mappedName;
+        return fieldMapping(fieldName, fieldName);
     }
 
     @Override
@@ -225,6 +223,9 @@ public String fieldMapping(ImmutableList<String> fieldPath) {
     @Override
     public String fieldMapping(String fieldName, String fieldValue) {
         String mappedName = "#" + sanitizeFieldMapping(fieldName);
+        while (nameMap.containsKey(mappedName) && !nameMap.get(mappedName).equals(fieldName)) {
+            mappedName = mappedName + "_";
+        }
         nameMap.put(mappedName, fieldValue);
         return mappedName;
     }
@@ -238,6 +239,9 @@ public String valueMapping(String fieldName, Object object) {
     public String constantMapping(String name, Object object) {
         String mappedName = ":" + sanitizeFieldMapping(name);
         AttributeValue value = schema.toAttrValue(object);
+        while (valMap.containsKey(mappedName) && !valMap.get(mappedName).equals(value)) {
+            mappedName = mappedName + "_";
+        }
         valMap.put(mappedName, value);
         return mappedName;
     }