2 files changed, 58 insertions, 2 deletions
diff --git a/src/main/java/gregtech/api/util/GT_Recipe.java b/src/main/java/gregtech/api/util/GT_Recipe.java
index a232096c85..6d660c67f6 100644
--- a/src/main/java/gregtech/api/util/GT_Recipe.java
+++ b/src/main/java/gregtech/api/util/GT_Recipe.java
@@ -5,6 +5,7 @@ import static gregtech.api.enums.Mods.GTPlusPlus;
 import static gregtech.api.enums.Mods.GregTech;
 import static gregtech.api.enums.Mods.NEICustomDiagrams;
 import static gregtech.api.enums.Mods.Railcraft;
+import static gregtech.api.util.GT_RecipeBuilder.handleRecipeCollision;
 import static gregtech.api.util.GT_RecipeConstants.ADDITIVE_AMOUNT;
 import static gregtech.api.util.GT_RecipeMapUtil.*;
 import static gregtech.api.util.GT_Utility.formatNumbers;
@@ -3738,7 +3739,40 @@ public class GT_Recipe implements Comparable<GT_Recipe> {
                 if (specialHandler != null) r = specialHandler.apply(r);
                 if (r == null) continue;
                 if (checkForCollision
-                    && findRecipe(null, false, true, Long.MAX_VALUE, r.mFluidInputs, r.mInputs) != null) continue;
+                    && findRecipe(null, false, true, Long.MAX_VALUE, r.mFluidInputs, r.mInputs) != null) {
+                    StringBuilder errorInfo = new StringBuilder();
+                    boolean hasAnEntry = false;
+                    for (FluidStack fStack : r.mFluidInputs) {
+                        if (fStack == null) {
+                            continue;
+                        }
+                        String s = fStack.getLocalizedName();
+                        if (s == null) {
+                            continue;
+                        }
+                        if (hasAnEntry) {
+                            errorInfo.append("+")
+                                .append(s);
+                        } else {
+                            errorInfo.append(s);
+                        }
+                        hasAnEntry = true;
+                    }
+                    for (ItemStack iStack : r.mInputs) {
+                        if (iStack == null) {
+                            continue;
+                        }
+                        String s = iStack.getDisplayName();
+                        if (hasAnEntry) {
+                            errorInfo.append("+" + s);
+                        } else {
+                            errorInfo.append(s);
+                        }
+                        hasAnEntry = true;
+                    }
+                    handleRecipeCollision(errorInfo.toString());
+                    continue;
+                }
                 ret.add(add(r));
             }
             if (!ret.isEmpty()) {
diff --git a/src/main/java/gregtech/api/util/GT_RecipeBuilder.java b/src/main/java/gregtech/api/util/GT_RecipeBuilder.java
index bdd09f0a34..0553d08805 100644
--- a/src/main/java/gregtech/api/util/GT_RecipeBuilder.java
+++ b/src/main/java/gregtech/api/util/GT_RecipeBuilder.java
@@ -1,6 +1,14 @@
 package gregtech.api.util;
 
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Optional;
 import java.util.function.Function;
 
 import javax.annotation.Nonnull;
@@ -126,6 +134,20 @@ public class GT_RecipeBuilder {
         }
     }
 
+    public static void handleRecipeCollision(String details) {
+        if (!PANIC_MODE && !DEBUG_MODE) {
+            return;
+        }
+        GT_Log.err.print("Recipe collision resulting in recipe loss detected with ");
+        GT_Log.err.println(details);
+        if (PANIC_MODE) {
+            throw new IllegalArgumentException("Recipe Collision");
+        } else {
+            // place a breakpoint here to catch all these issues
+            new IllegalArgumentException().printStackTrace(GT_Log.err);
+        }
+    }
+
     /**
      * Non-OreDicted item inputs. Assumes input is unified.
      */