From 695ce382ec6dbdddcad239176f03ba23e7f635d6 Mon Sep 17 00:00:00 2001
From: Freagarach <freagarach@wildfiregames.com>
Date: Thu, 9 Dec 2021 16:22:52 +0000
Subject: [PATCH] Fix Trainer/Researcher without entities/techs.

It was explicitly allowed in 0c4f59d0a7, but not all references to
`this.template` were properly checked.

Noticed by: @nwtour
Differential revision: https://code.wildfiregames.com/D4357
Tested by: @nwtour
Comments by: @Stan
This was SVN commit r26043.
---
 .../data/mods/public/simulation/components/Researcher.js | 8 ++------
 .../data/mods/public/simulation/components/Trainer.js    | 8 +++-----
 .../simulation/components/tests/test_Researcher.js       | 8 ++++++++
 .../public/simulation/components/tests/test_Trainer.js   | 9 +++++++++
 4 files changed, 22 insertions(+), 11 deletions(-)

diff --git a/binaries/data/mods/public/simulation/components/Researcher.js b/binaries/data/mods/public/simulation/components/Researcher.js
index 94b6ed0131..ea5de6d2ab 100644
--- a/binaries/data/mods/public/simulation/components/Researcher.js
+++ b/binaries/data/mods/public/simulation/components/Researcher.js
@@ -218,11 +218,7 @@ Researcher.prototype.Deserialize = function(data)
  */
 Researcher.prototype.GetTechnologiesList = function()
 {
-	if (!this.template.Technologies)
-		return [];
-
-	const string = ApplyValueModificationsToEntity("Researcher/Technologies/_string", this.template.Technologies._string, this.entity);
-
+	const string = ApplyValueModificationsToEntity("Researcher/Technologies/_string", this.template?.Technologies?._string || "", this.entity);
 	if (!string)
 		return [];
 
@@ -309,7 +305,7 @@ Researcher.prototype.GetTechnologiesList = function()
 Researcher.prototype.GetTechCostMultiplier = function()
 {
 	const techCostMultiplier = {};
-	for (const res in this.template.TechCostMultiplier)
+	for (const res in this.template?.TechCostMultiplier)
 		techCostMultiplier[res] = ApplyValueModificationsToEntity(
 		    "Researcher/TechCostMultiplier/" + res,
 		    +this.template.TechCostMultiplier[res],
diff --git a/binaries/data/mods/public/simulation/components/Trainer.js b/binaries/data/mods/public/simulation/components/Trainer.js
index 4d7ad215a2..879b680b66 100644
--- a/binaries/data/mods/public/simulation/components/Trainer.js
+++ b/binaries/data/mods/public/simulation/components/Trainer.js
@@ -461,10 +461,8 @@ Trainer.prototype.CalculateEntitiesMap = function()
 	// Don't reset the map, it's used below to update entities.
 	if (!this.entitiesMap)
 		this.entitiesMap = new Map();
-	if (!this.template.Entities)
-		return;
 
-	const string = this.template.Entities._string;
+	const string = this.template?.Entities?._string || "";
 	// Tokens can be added -> process an empty list to get them.
 	let addedTokens = ApplyValueModificationsToEntity("Trainer/Entities/_string", "", this.entity);
 	if (!addedTokens && !string)
@@ -577,7 +575,7 @@ Trainer.prototype.GetUpgradedTemplate = function(templateName)
 Trainer.prototype.GetTrainCostMultiplier = function()
 {
 	const trainCostMultiplier = {};
-	for (const res in this.template.TrainCostMultiplier)
+	for (const res in this.template?.TrainCostMultiplier)
 		trainCostMultiplier[res] = ApplyValueModificationsToEntity(
 		    "Trainer/TrainCostMultiplier/" + res,
 		    +this.template.TrainCostMultiplier[res],
@@ -594,7 +592,7 @@ Trainer.prototype.GetBatchTime = function(batchSize)
 	// TODO: work out what equation we should use here.
 	return Math.pow(batchSize, ApplyValueModificationsToEntity(
 	    "Trainer/BatchTimeModifier",
-	    +(this.template.BatchTimeModifier || 1),
+	    +(this.template?.BatchTimeModifier || 1),
 	    this.entity));
 };
 
diff --git a/binaries/data/mods/public/simulation/components/tests/test_Researcher.js b/binaries/data/mods/public/simulation/components/tests/test_Researcher.js
index 74e4b58a0d..3f1bfa3370 100644
--- a/binaries/data/mods/public/simulation/components/tests/test_Researcher.js
+++ b/binaries/data/mods/public/simulation/components/tests/test_Researcher.js
@@ -151,3 +151,11 @@ spyTechManager = new Spy(techManager, "ResearchTechnology");
 TS_ASSERT_EQUALS(cmpResearcher.Progress(id, 1000), 500);
 TS_ASSERT_EQUALS(spyTechManager._called, 1);
 TS_ASSERT_EQUALS(cmpResearcher.queue.size, 0);
+
+
+// Test that we can affect an empty researcher.
+Engine.RegisterGlobal("ApplyValueModificationsToEntity", (_, value) => value + "some_test");
+TS_ASSERT_UNEVAL_EQUALS(
+	ConstructComponent(entityID, "Researcher", null).GetTechnologiesList(),
+	["some_test"]
+);
diff --git a/binaries/data/mods/public/simulation/components/tests/test_Trainer.js b/binaries/data/mods/public/simulation/components/tests/test_Trainer.js
index ccd69cb417..e29b83bc81 100644
--- a/binaries/data/mods/public/simulation/components/tests/test_Trainer.js
+++ b/binaries/data/mods/public/simulation/components/tests/test_Trainer.js
@@ -299,3 +299,12 @@ TS_ASSERT_UNEVAL_EQUALS(
 TS_ASSERT_EQUALS(cmpTrainer.queue.size, 1);
 TS_ASSERT_EQUALS(cmpTrainer.GetBatch(id1), undefined);
 TS_ASSERT_EQUALS(cmpTrainer.GetBatch(id2).unitTemplate, "units/iber/c");
+
+
+// Test that we can affect an empty trainer.
+const emptyTrainer = ConstructComponent(entityID, "Trainer", null);
+emptyTrainer.OnValueModification({ "component": "Trainer", "entities": [entityID], "valueNames": ["Trainer/Entities/"] });
+TS_ASSERT_UNEVAL_EQUALS(
+	emptyTrainer.GetEntitiesList(),
+	["units/iber/d"]
+);