3 files changed, 28 insertions, 1 deletions

diff --git a/src/main/java/cuchaz/enigma/Deobfuscator.java b/src/main/java/cuchaz/enigma/Deobfuscator.java
index b2f361e9..4bd9414d 100644
--- a/src/main/java/cuchaz/enigma/Deobfuscator.java
+++ b/src/main/java/cuchaz/enigma/Deobfuscator.java
@@ -463,7 +463,7 @@ public class Deobfuscator {
         } else if (obfEntry instanceof ConstructorEntry) {
             throw new IllegalArgumentException("Cannot rename constructors");
         } else if (obfEntry instanceof ArgumentEntry) {
-            this.renamer.setArgumentName((ArgumentEntry) obfEntry, newName);
+            this.renamer.setArgumentTreeName((ArgumentEntry) obfEntry, newName);
         } else {
             throw new Error("Unknown entry type: " + obfEntry.getClass().getName());
         }
diff --git a/src/main/java/cuchaz/enigma/mapping/ArgumentEntry.java b/src/main/java/cuchaz/enigma/mapping/ArgumentEntry.java
index 741849a9..662516da 100644
--- a/src/main/java/cuchaz/enigma/mapping/ArgumentEntry.java
+++ b/src/main/java/cuchaz/enigma/mapping/ArgumentEntry.java
@@ -46,6 +46,12 @@ public class ArgumentEntry implements Entry {
         this.name = other.name;
     }
 
+    public ArgumentEntry(ArgumentEntry other, BehaviorEntry entry) {
+        this.behaviorEntry = entry;
+        this.index = other.index;
+        this.name = other.name;
+    }
+
     public BehaviorEntry getBehaviorEntry() {
         return this.behaviorEntry;
     }
diff --git a/src/main/java/cuchaz/enigma/mapping/MappingsRenamer.java b/src/main/java/cuchaz/enigma/mapping/MappingsRenamer.java
index 80028137..5d23dc0b 100644
--- a/src/main/java/cuchaz/enigma/mapping/MappingsRenamer.java
+++ b/src/main/java/cuchaz/enigma/mapping/MappingsRenamer.java
@@ -148,6 +148,27 @@ public class MappingsRenamer {
         classMapping.setMethodName(obf.getName(), obf.getSignature(), obf.getName());
     }
 
+    public void setArgumentTreeName(ArgumentEntry obf, String deobfName) {
+        if (!(obf.getBehaviorEntry() instanceof MethodEntry)) {
+            setArgumentName(obf, deobfName);
+            return;
+        }
+
+        MethodEntry obfMethod = (MethodEntry) obf.getBehaviorEntry();
+
+        Set<MethodEntry> implementations = m_index.getRelatedMethodImplementations(obfMethod);
+        for (MethodEntry entry : implementations) {
+            // NOTE: don't need to check arguments for name collisions with names determined by Procyon
+            if (m_mappings.containsArgument(entry, deobfName)) {
+                throw new IllegalNameException(deobfName, "There is already an argument with that name");
+            }
+        }
+
+        for (MethodEntry entry : implementations) {
+            setArgumentName(new ArgumentEntry(obf, entry), deobfName);
+        }
+    }
+
     public void setArgumentName(ArgumentEntry obf, String deobfName) {
         deobfName = NameValidator.validateArgumentName(deobfName);
         // NOTE: don't need to check arguments for name collisions with names determined by Procyon