Fix an exception when recipe-hovering with a pathological configurati…

…on. (#150)

Specifically, an ArgumentOutOfRangeException happens when hovering over
a recipe that is unlocked by a technology that (directly or indirectly)
requires a science pack that is both (a) inaccessible and (b) not a
milestone.

For an example of this in action, load [this vanilla
project](https://github.com/user-attachments/files/15782026/exception.zip)
and hover over either of the two personal roboport recipe icons. Both
will cause an exception, but the steel recipe icon won't. Open the
milestones editor and add Chemical science pack to the milestones.
Alternatively, open the Dependency explorer for the Chemical science
pack item, and click "Clear mark". In both cases, the exceptions will
disappear.

Yafc.Model/Analysis/TechnologyScienceAnalysis.cs

@@ -7,11 +7,15 @@ public class TechnologyScienceAnalysis : Analysis {
         public Mapping<Technology, Ingredient[]> allSciencePacks { get; private set; }
 
         public Ingredient? GetMaxTechnologyIngredient(Technology tech) {
-            var list = allSciencePacks[tech];
+            Ingredient[] list = allSciencePacks[tech];
             Ingredient? ingredient = null;
             Bits order = new Bits();
-            foreach (var entry in list) {
-                var entryOrder = Milestones.Instance.GetMilestoneResult(entry.goods.id) - 1;
+            foreach (Ingredient entry in list) {
+                Bits entryOrder = Milestones.Instance.GetMilestoneResult(entry.goods.id);
+                if (entryOrder != 0) {
+                    entryOrder -= 1;
+                }// else: The science pack is not accessible *and* not a milestone. We may still display it, but any actual milestone will win.
+
                 if (ingredient == null || entryOrder > order) {
                     order = entryOrder;
                     ingredient = entry;

changelog.txt

@@ -13,6 +13,7 @@ Date: soon
     Fixes:
         - Display spent fuel items in the production table and link summaries.
         - Fix error when switching items in NEIE with middle-click
+        - Fix an exception when hovering over recipes in certain pathological cases.
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 Version: 0.7.0
 Date: May 25th 2024