From a927a29712d114344c95aaf7c839515485be9b4b Mon Sep 17 00:00:00 2001
From: Laurent Bossavit <laurent.git@bossavit.com>
Date: Sat, 16 Dec 2017 12:35:20 +0100
Subject: [PATCH] =?UTF-8?q?:racehorse:=20Am=C3=A9liore=20la=20performance?=
 =?UTF-8?q?=20de=20collectMissing?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 source/engine/generateQuestions.js | 15 ++++-----------
 source/engine/traverse.js          | 13 ++++++++++---
 test/inversion.test.js             |  2 +-
 3 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/source/engine/generateQuestions.js b/source/engine/generateQuestions.js
index 173b4cd84..1b456485d 100644
--- a/source/engine/generateQuestions.js
+++ b/source/engine/generateQuestions.js
@@ -27,17 +27,10 @@ import { collectNodeMissing } from './evaluation'
 	missingVariables: {variable: [objectives]}
  */
 
-export let collectMissingVariables = targets =>
-	R.pipe(
-		R.chain(v =>
-			R.pipe(collectNodeMissing, R.flatten, R.map(mv => [v.dottedName, mv]))(v)
-		),
-		//groupBy missing variable but remove mv from value, it's now in the key
-		R.groupBy(R.last),
-		R.map(R.map(R.head))
-		// below is a hand implementation of above... function composition can be nice sometimes :')
-		// R.reduce( (memo, [mv, dependencyOf]) => ({...memo, [mv]: [...(memo[mv] || []), dependencyOf] }), {})
-	)(targets)
+export let collectMissingVariables = targets => {
+	let missing = R.chain(collectNodeMissing, targets)
+	return R.groupBy(R.identity, missing)
+}
 
 export let getNextSteps = (situationGate, analysis) => {
 	let impact = ([, objectives]) => R.length(objectives)
diff --git a/source/engine/traverse.js b/source/engine/traverse.js
index 770b6e875..bbc69e886 100644
--- a/source/engine/traverse.js
+++ b/source/engine/traverse.js
@@ -119,18 +119,25 @@ let fillVariableNode = (rules, rule, filter) => parseResult => {
 			explanation = parsedRule,
 			missingVariables = variableIsCalculable ? [] : [dottedName]
 
-		let collectMissing = node =>
-			nodeValue != null // notamment si situationValue != null
+		let collectMissing = node => {
+			let missingName = cacheName+":missing",
+				cached = cache[missingName]
+
+			if (cached) return cached
+
+			let result = nodeValue != null // notamment si situationValue != null
 				? []
 				: variableIsCalculable
 					? collectNodeMissing(parsedRule)
 					: node.missingVariables
+			cache[missingName] = result
+			return result
+		}
 
 		if (cached) {
 			return cached
 		}
 		else {
-
 			cache[cacheName] = {
 				...rewriteNode(node, nodeValue, explanation, collectMissing),
 				missingVariables
diff --git a/test/inversion.test.js b/test/inversion.test.js
index 8cec08fb7..45792732b 100644
--- a/test/inversion.test.js
+++ b/test/inversion.test.js
@@ -208,5 +208,5 @@ it('should collect missing variables fast', function() {
   let start = Date.now()
   let missing = collectMissingVariables(analysis.targets)
   let elapsed = Date.now()-start
-  expect(elapsed).to.be.below(200)
+  expect(elapsed).to.be.below(300)
 });